rams horn exhaust info you might need

grumpyvette

Administrator
Staff member
theres three common versions, of the rams horn exhaust manifold design.
heres some threads to look thru, don,t ignore the sub links, keep in mind stock exhaust manifolds, even the rams horn corvette 2.5" versions start to be restrictive by 4000 rpm, and on any headers a low restriction exhaust behind the manifolds or headers collectors are MANDATORY if you expect the headers to work anywhere near full potential.
as a general rule youll want intake port and runner flow numbers near 2.5 cfm per horsepower
for decent performance

viewtopic.php?f=56&t=1303

viewtopic.php?f=56&t=495

viewtopic.php?f=56&t=3155

http://garage.grumpysperformance.com/index.php?threads/building-an-exhaust-system-for-your-car.1166/

http://www.naparts.net/Exhaust/Exhaust- ... 90544.html

the 2" exhaust found on several Chevy cars

http://www.performanceexhaustplus.com/p ... rod_id=125
airflowen.png

exarea.gif

expik.png

keep in mind that the rams horn exhaust manifold does not flow nearly as well as many aftermarket headers with individual exhaust primary pipes on each exhaust port on the cylinder head, and the 2.5" exhaust pipes start to become restrictive to flow at about 4500 rpm on your average 350 sbc, no mater what the engine size you have the amount of exhaust, can be calculated at your exhaust becomes restrictive once exhaust flow rates of about 115 cfm per square inch of exhaust pipe cross sectional area is approached.
the 2.5" versions originally exclusive too corvettes

http://www.castheads.com/corvette_systems.php

the improved stainless aftermarket design

http://www.speedwaymotors.com/p/5425,41 ... folds.html
Headersvsmanifolds.jpg

http://www.speedwaymotors.com/Stainless ... ,5425.html
http://www.speedwaymotors.com/ProductSu ... s&deptId=0
stainlessramshorn.jpg
 
Last edited by a moderator:

dcairns

New Member
Re: rams horn exhaust

https://www.castheads.com/manifolds-carb/exhaust-manifolds/corvette-exhaust-manifolds/


http://www.superchevy.com/how-to/ex...about-corvette-headers-and-exhaust-manifolds/

https://www.jegs.com/p/Flowtech/Flo...Vgo3ICh1ihg0PEAMYAyAAEgLrW_D_BwE&gclsrc=aw.ds

http://outintheshop.com/faq/casting/exhaust_man.html
Exhaust Manifold ID
http://outintheshop.com/faq/casting/exhaust_man.html
SEARCH cast numbers

Use these casting numbers to identify the exhaust manifolds you have.

Casting Number
Years
Engine
Side
Comments
336706
74-78
350
RH

336707
74-78
350
LH

336708
74-78
350
RH

336709
74-78
350
RH
Camaro & Z-28 with A.I.R.
336710
74-78
307, 350 & 400
LH
Chevelle, Camaro, Z-28, Nova and Passenger with A.I.R.
346222
74-80
307, 350 & 400
RH
Chevelle, Camaro, Nova and Passenger with A.I.R.
346247
75-77
262, 350 & 400
LH
Chevelle, Camaro, Monte Carlo and Passenger 110, 145, 155 & 175 HP
346248
75-77
262, 350 & 400
RH
Chevelle, Camaro, Monte Carlo and Passenger 110, 145, 155 & 175 HP
354432
75-76
262
RH
110 HP
354433
75-76
262
LH
110 HP
364753
76-80
307, 350 & 400
LH
Camaro, Monte Carlo, Malibu and Passenger
372243
74-83
307, 350 & 400
RH
Corvette and Replacement manifold
462697
77-79
267 & 305
LH
Monte Carlo and Malibu
462698
77-83
267 & 305
RH
Monte Carlo and Malibu
474008
78-82
267, 305 & 350
RH

745994
80-86
267 & 305
LH

3704791
55-56
265
LH
Corvette and Passenger 195 HP
3704792
55-56
265
RH
Corvette and Passenger 195 HP
3725563
56
265
LH & RH
Corvette and Passenger 210 HP 2-Bolt Flange
3731557
56
265
LH
Corvette and Passenger 225 HP
3731558
56
265
RH
Corvette and Passenger 225 HP
3732498
58
283
RH
Corvette FI
3733975
57
283
LH
Corvette and Passenger 220, 245, 250, 270 & 283 HP
3733976
57
283
RH
Corvette and Passenger 220, 245, 250, 270 & 283 HP
3737902
62-65
327
RH
300, 340, 360, 365 & 375 HP 2.5" Outlet
3746563
65
327
LH
300 HP
3747038
58-65
283 & 327
RH
Corvette and Passenger 220, 250 & 300 HP 1.9" Outlet
3747042
58-68
283, 307 & 327
RH
Corvette and Passenger 195, 200, 220, 250, 270, 275, 290, 300 & 350 HP 1.9" Outlet
3747938
64
327
LH & RH
250 & 300 HP
3747942
65
327
LH & RH
250, 350 & 365 HP
3749965
58-63
283 & 327
LH
Corvette and Passenger 230, 245, 250, 270, 275, 290, 300 & 315 HP
3750556
58-65
283 & 327
RH
Corvette and Passenger 230, 245, 250, 270, 275, 290, 300 & 315 HP
3780728
64-67
327
LH
Chevy II
3790729
64-67
283 & 327
LH
195, 220, 250, 270, 275, 300 & 350 HP 2.0" Outlet Chevy II
3790730
64-65
283 & 327
RH
220, 250 & 300 HP 1.9" Outlet Chevy II
3791162
65-66
283 & 327
RH
Chevy II with AC
3791182
66-67
283 & 327
RH
Passenger with AC
3797901
62-63
327
LH
Corvette 300, 340 & 360 HP
3797902
62-65
327
RH
Corvette 300, 340, 360, 365 & 375 HP 2.5" Outlet
3797942
63-65
327
LH & RH
Corvette 300, 360, 365 & 375 HP 2.5" Outlet
3834947
64-68
283, 307 & 327
LH
Chevelle 195, 200, 210, 220, 250, 275, 295, 300, 325, 350 & 365 HP 2.0" Outlet
3836968
55-56
265
RH
Corvette and Passenger 195 HP
3837069
55
265
LH
Corvette and Passenger 195 HP
3840715
64
283 & 327
LH
Chevelle
3840912
64-68
283, 307, 327 & 350
RH
Chevelle, Camaro and Nova 195, 200, 210, 220, 250, 275, 295, 300, 325, 350 & 365 HP 1.9" Outlet
3846559
64-71
327 & 350
LH
Corvette 250, 270, 300 & 350 HP 2.0" Outlet
3846563
64-65
327
LH
Corvette 300, 350 & 365 HP 2.5" Outlet
3846659
66
327
LH
350 HP
3849288
64-67
283 & 327
RH
195, 220, 275 & 350 HP 1.9" Outlet Chevy II
3849290
64-67
283 & 327
RH
195, 220, 275 & 350 HP 1.9" Outlet Chevy II with AC
3855163
65-68
283, 307 & 327
LH
Passenger and Truck 195, 200, 220, 250 & 275 HP 2.0" Outlet
3872723
66-67
283 & 327
LH
195, 220, 275 & 350 HP 2.0" Outlet Chevy II A.I.R.
3872729
66
283 & 327
LH
Chevelle 195,220, 275 & 350 HP 2.0" Outlet A.I.R.
3872730
66-68
283, 302, 307 & 327
RH
Chevelle, Camaro & Z-28 200, 210, 220, 250, 275, 290, 325 & 350 HP 1.9" Outlet A.I.R.
3872738
66-67
283 & 327
RH
195, 220, 275 & 350 HP 1.9" Outlet Chevy II
3872741
66-68
283, 307 & 327
LH
Passenger 195, 200, 220, 250 & 275 HP 2.0" Outlet A.I.R.
3872765
67-71
327 & 350
LH
Corvette 300, 330, 350 & 370 HP 2.0" Outlet A.I.R.
3872778
66-68
283, 307 & 327
RH
Corvette, Passenger and Truck 195, 200, 250, 275, 300 & 350 HP 1.9" Outlet A.I.R.
3887186
66
283
RH
220 HP 1.9" Outlet
3890424
64-67
283 & 327
RH
Chevy II
3892679
66-68
283, 302, 307, 327 & 350
LH
Chevelle, Camaro and Z-28 195, 200, 210, 220, 250, 275, 290, 295 & 325 HP 2.0" Outlet
3892683
66-68
283, 302, 307, 327 & 350
LH
Chevelle, Camaro and Z-28 195, 200, 210, 220, 250, 275, 290, 295 & 325 HP 2.0" Outlet
3893604
66-68
283 & 327
RH
Passenger A.I.R.
3893608
67-68
283, 302, 307, 327 & 350
RH
Chevelle, Camaro and Z-28 195, 200, 210, 250, 275, 290, 295 & 325 HP 1.9" Outlet
3896956
67-68
283 & 327
RH
Truck
3905364
69-72
307, 350 & 400
RH
Truck
3932376
69-70
307, 327, 350 & 400
RH
Chevelle and Camaro 200, 210, 250, 255, 265 & 300 HP 1.9" Outlet
3932461
69-74
327 & 350
LH & RH
Corvette 190, 195, 200, 235, 255, 300, 330 & 350 HP 1.9" Outlet A.I.R.
3932465
69-70
327, 350 & 400
RH
Passenger 235, 250, 255, 265, 300 & 350 HP 1.9" Outlet
3932469
69-70
327 & 350
LH
Passenger 235, 250, 255 & 300 HP 2.0" Outlet
3932473
69-70
327, 350 & 400
LH
Passenger 235, 250, 255, 265 & 300 HP 2.0" Outlet
3932481
69
350
RH
Corvette
3940972
67
350
RH
Camaro 295 HP
3942527
69-70
302, 307, 327 & 350
LH
Chevelle, Camaro, Z-28 and Nova 200, 210, 250, 255, 290, 300 & 360 HP 2.0" Outlet A.I.R.
3942529
69-70
302, 307, 327, 350 & 400
LH
Chevelle, Camaro and Nova 200, 210, 250, 255, 290 & 300 HP 2.0" Outlet
3946826
69-70
302, 307, 327 & 350
RH
Chevelle, Camaro, Z-28 and Nova200, 210, 250, 255, 290, 300 & 360 HP 1.9" Outlet A.I.R.
3959562
72-74
307, 350 & 400
RH
Chevelle, Camaro and Z-28 115, 130, 145, 150, 160, 165, 170, 175, 180, 185 & 245 HP 2.0" Outlet A.I.R.
3973432
70-74
307, 350 & 400
RH
Chevelle, Camaro, Nova and Passenger 115, 130, 150, 165, 170, 175, 180, 200, 245, 250, 255, 270 & 300 HP 2.0" Outlet
3986330
69-73
302, 307, 327 & 350
RH
Camaro and Z-28 200, 210, 245, 250, 255, 290, 300, 330 & 360 HP 1.9" Outlet A.I.R.
3989036
71-75
350
LH & RH
Corvette and Passenger 165, 195, 200, 205 & 270 HP 2.0" Outlet with and without A.I.R.
3989041
69-74
302, 307, 327, 350 & 400
LH
Camaro, Z-28 and Nova 115, 130, 145, 150, 160, 165, 170, 180, 185, 200, 210, 245, 250, 255, 290, 300, 330 & 360 HP 2.0" Outlet with and without A.I.R.
3989043
70-73
307, 350 & 400
LH
Chevelle, Camaro, Nova and Passenger 105, 115, 130, 145, 150, 165, 175, 185, 200, 245, 250, 255, 270 & 300 HP 2.0" Outlet with and without A.I.R.
3989055
69-72
307, 350 & 400
LH

3997742
71-78
307 & 350
RH
2.0" Outlet
3998902
72-78
307 & 350
RH

10045315
88-94
305 & 350
LH

10045317
88-94
305 & 350
LH

10045317
88-94
305 & 350
LH

10046123
87-92
305 & 350
LH

10046139
84-85
350
LH

10046140
84-85
350
RH

10055734
87-91
350
RH

10092901
89-91
350
LH

10092903
89-94
350
LH

10092905
89-94
350
LH

10108437
87-93
305 & 350
RH

10128448
91-93
305 & 350
LH

10128483
91-93
305 & 350
LH

10166144
91-94
350
RH

10166145
87-90
305 & 350
LH

10166147
89-94
305 & 350
LH

10166158
89-94
305 & 350
RH

10168494
94
265 & 350
LH

10207656
93-94
350
LH

10207657
93
350
RH

10433037
82-86
305
LH

12550621
94
265
RH

12550622
91
350
RH

14007400
80-86
267 & 305
LH

14014437
80-84
305
LH

14014438
80-84
305
RH

14014459
81-86
305 & 350
LH

14014500
79-86
267, 305 & 350
RH

14022625
80-81
305
LH

14031361
82-86
305
RH

14031376
81-86
350
RH

14034069
81-86
350
RH

14034075
81-86
305 & 350
LH

14043373
82-86
305
LH

14050233
83-86
305 & 350
LH

14050282
83-87
305 & 350
RH

14050287
82-86
305
LH

14057029
84-85
350
LH

14057030
84-85
350
RH

14060630
81-86
350
RH

14060633
81-86
305 & 350
LH

14067365
77-86
267, 305, 350 & 400
LH

14068667
85-88
350
LH

14068670
85-88
350
RH

14071200
83-86
305
RH

14075611
83-86
305
LH

14079295
85-86
305 & 350
LH

14079296
85-86
305 & 350
RH

14087511
86-91
350
LH

14087512
86-91
350
RH

14093653
87-90
305 & 350
LH

14093654
87-90
305 & 350
RH

14093655
87-90
305 & 350
LH

14093658
88-94
305 & 350
RH

14093660
87-90
305 & 350
RH

14093682
87-90
305 & 350
RH

14094045
87-90
305 & 350
LH

14094063
87-92
305 & 350
LH

14094064
87-92
305 & 350
RH

14094065
85-88
350
RH

14101054
87-88
305 & 350
RH

14102016
88-94
305 & 350
RH

14102018
89-94
305 & 350
RH

14103206
87-91
305 & 350
RH

14103207
87-91
305 & 350
LH

329225
73-76
454
LH
Chevelle and Passenger with and without A.I.R.
353028
73-76
454
LH
Chevelle and Passenger with and without A.I.R.
353030
73-76
454
LH
Police
3732793
58-61
348
LH
Passenger
3732794
58-61
348
RH
Passenger
3767583
59-61
348 & 409
LH
Passenger
3767584
59-61
348 & 409
RH
Passenger
3814682
62-64
409
RH
Passenger
3814683
62-64
409
LH
Passenger
3822925
62-64
409
LH
Passenger & Z-11
3822926
62-64
409
RH
Passenger & Z-11
3855161
65
409
LH
Passenger 340 & 400 HP
3855162
65
409
RH
Passenger 340 & 400 HP
3856297
65
396
LH
325 HP
3856301
65
396
LH
425 HP Corvette
3856302
65
396
RH
425 HP Corvette
3856306
65
396
RH
Passenger 325 HP
3857297
65
396
LH
Passenger 325 HP
3868874
65-66
396
RH
Chevelle 325, 360 & 375 HP Z-16
3869925
65
396
LH
Chevelle 375 HP Z-16
3872770
66
396
RH

3880827
66-69
427 & 454
LH
Corvette
3880828
66-72
427 & 454
RH
Corvette 270, 365, 390 & 425 HP with and without A.I.R. LS-5 & LS-6
3880869
70-72
454
LH
Corvette 365 & 425 HP with and without A.I.R. LS-5 & LS-6
3883827
66
427
LH
Passenger
3883828
66
427
RH
Passenger
3883999
66
396
LH
Chevelle 325, 360 & 375 HP
3884504
66-67
396 & 427
RH
Passenger 325, 385 & 390 HP
3892307
66-67
396 & 427
LH
Passenger 325 & 390 HP
3902401
67
396
LH
Chevelle
3904399
66
396
LH

3909879
67-70
396, 427 & 454
LH
Chevelle, Camaro and Nova 325, 350, 375, 425, 430 & 450 HP LS-6 COPO
3909880
67
396
RH
Chevelle and Camaro 325, 350 & 375 HP
3914613
68-70
396 & 427
LH
Passenger 265, 325, 335, 345, 390 & 425 HP
3916178
68-70
396, 427 & 454
RH
Chevelle, Camaro, Nova and Passenger 325, 350, 375, 425, 430 & 450 HP COPO LS-5 & LS-6
3969869
70-74
454
LH
Corvette 270, 365 & 390 HP with and without A.I.R. LS-5
3989310
71-72
402 & 454
RH
Chevelle, Camaro, Monte Carlo and Passenger
3989343
71-72
402 & 454
LH
Chevelle, Camaro, Monte Carlo and Passenger
3994045
73-75
454
LH
Police


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For "newer" cars with alternators, Corvette Paragon has a correct reproductions of 2.5 inch rams horns. Only down side is the price. speedway motors has a slightly updated and in theory improved manifold in a couple versions
expik.png

http://www.speedwaymotors.com/Smoot...-Manifolds-Small-Block-Chevy-Black,94197.html

http://www.jegs.com/p/Flowtech/Flow...ifolds-for-Small-Block-Chevy/3130358/10002/-1

https://www.summitracing.com/parts/...MIm9idzM_J2AIV1DyBCh1kYg2mEAQYBCABEgJRPPD_BwE

summit sells nicer chrome versions

g9200.jpg


af6940b.jpg

http://www.speedwaymotors.com/Flowt...rn-Exhaust-Manifold-Chrome-Finish,141137.html
d5d0d3d.jpg


Casting #3846563 2.5 inch rams horn. Correct for 1964 passenger 327/300 and Corvette 327/300,365 and 375 . The down

http://www.corvette-paragon.com/p-355237-exhaust-manifold-lh-2-12.aspx
ram4.jpg


vettemanifold1a.gif


Right hand casting 3797942. Correct for 1964 passenger 327/300/365/375 and Corvette 327/300 and 365.

http://www.corvette-paragon.com/p-357760-exhaust-manifold-wchoke-tube-rh-2-12.aspx

ram5.jpg

IMG_1912.jpg


YOULL GENERALLY WANT TO USE AN EXHAUST PIPE DIAM. AT LEAST AS LARGE AS THE RAMS HORN MANIFOLD EXHAUST DIAM>



ram1.jpg


There is a huge difference in flow potential between the 2.5 inch corvette exhaust design and standard pass car 2 inch rams horns.


ram2.jpg


They fit and look just fine.

PSI_4401-L.jpg

ram3.jpg


BTW, I've frequently seen O.E.M. rams horn exhaust manifolds with rather unsightly both external and flow restricting ,internal, heated air tube extensions , used on chokes and emission connections,these tubes can be removed,
IF you don,t need them in your application, personally I've just drilled the tube out and MIG welded the hole shut than used a disc grinder to smooth the welded area so it looks like it was never there!
 
Last edited by a moderator:

grumpyvette

Administrator
Staff member
Re: rams horn exhaust
http://www.mre-books.com/chevy/engines/parts_interchange/exhaust.html


3747042 - RH rams horn ex manifold

1965 Passenger 283/195hp
1965 Corvette 327/250hp & 300hp auto trans w/ac
1966/67 Passenger 283/195hp and 220hp w/o A.I.R.
1966/67 Passenger 327/275hp w/o A.I.R
1966/67 Corvette 327/300;350hp w/o A.I.R.
1968 Passenger 307/200hp with auto trans
1968 Passenger 327/250 and 275hp

On the LH, the closest number I can find is 3932473 which is curved outlet type:
1969 Passenger 327/235hp w/auto with A.I.R.
1969 Passenger 350/250,255,300hp manual trans with A.I.R
1969 casting was tapped for A.I.R
1970 Passenger 350/250,300hp w/o A.I.R.
1970 Passenger 400/265hp
1970 casting was not tapped for A.I.R.




thanks for posting the additional source, info on those manifolds as IM sure that info helps, as those original manifolds are becoming harder to find
HERES INFO DCARINS POSTED

but before you decide that RAMS HORN EXHAUST is all you need,
be aware that it makes a HUGE difference what rpm,your engine will be expected to make power in,your engines displacement, your cam timing and how restrictive the exhaust system is behind the headers or exhaust manifolds. at low and mid rpms a well designed exhaust with 2.5" pipes may act like an extended header collector and you can make reasonably good torque, but look closely at the graphs and the rpm range they were plotted over, notice the RAMS HORN EXHAUST makes for decent results
but its EFFICIENCY is falling rapidly as ENGINE RPMS INCREASE
if your engine had a fairly larger 383-406 displacement, a decent cam with a fairly tight LSA lets say something with about 240 degrees or more at .050 lift or more and compression up at or over about 10:1 you would be strangling an engine designed to produce power up in the 6500rpm range.
RAMS HORN MANIFOLDS work very well at off idle to about 4000rpm but headers usually produce better power above 4000rpm
but if the exhaust system behind the headers or the cam timing is not set up to maximize the higher rpm port flow rates and cylinder head flow or intake flow rates,are restrictive theres not much to be gained with headers, remember headers by design must operate with near zero back pressure to maximize cylinder scavenging
look closely at the dyno results posted lower in this thread, notice the restrictive exhaust has already made the torque start dropping off by about 3500rpm and remember the torque curve closely follows the cylinder fill or volumetric efficiency, so its obvious the rams horn exhaust or the exhaust behind them are restricting flow

volumetric.gif

your torque curve closely matches the cylinder fill and scavenge efficiency

READ THRU THESE RELATED LINKS
viewtopic.php?f=56&t=495

viewtopic.php?f=52&t=5154

viewtopic.php?f=52&t=1070

viewtopic.php?f=56&t=1503

viewtopic.php?f=56&t=1303

viewtopic.php?f=55&t=8485&p=29767&hilit=volumetric#p29767
I had my newly built, mild 383 run on a dyno. It is going in my 64 Impala, so good torque was important as was keeping the idle civilized enough for power brakes and air conditioning. Given those constraints and the stock block, heads and intake manifold tow work with, it came out rather well.

YouTube Video of some of the dyno runs


One of the things I wanted to test was the headers vs stock rams horns exhaust manifold topic that seems to come up from time to time. Since this engine is made of stock castings, overall breathing ability is rather limited. So the headers never really get a chance to show much advantage at the extreme top end. The rams horns are reproduction 2.5 inch manifolds that have the correct casting numbers on them. They were mildly ported and the anti-reversion bumps removed.


PSI_3221.jpg





I have to say, that in my test conditions, using the rams horns is a no brainer. Why deal the disadvantages of headers for such a small gain?


Dyno-Stock2.5.jpg





What made a bigger impact on performance was adding the 2.5 to 2 inch reducers to the pipes, to simulate what actually happens at the muffler on the stock exhaust system on the 64 Impala. It also points out that an all 2.5 inch exhaust system would be an advantage.


Dyno-Stock2.jpg





And just for fun I did a run with the stock air cleaner and filter in place, along with the 2.5 to 2 inch reducers on the exhaust (trying to simulate how it will be once installed in the Impala). On a 64 Impala the air cleaner horn has a remarkably small opening and I was expecting it to really cause a hit on the performance.


Dyno-Stock2withAirCleaner.jpg




Surprisingly, the air cleaner/filter had little impact. This is probably highlighting how restricted the intake manifold is. I am thinking it might be worth porting the intake a bit to pick up some more power higher up the RPM range. I don’t think a mild port would have much if any effect on idle quality, since it is a 383 breathing through a 327’s intake.

thats very impressive info, but I must point out, BEFORE you go thinking rams horn exhaust manifolds are almost as effective as headers,.....you need to remember that its the complete combo, not just the swap from headers from rams horn exhaust manifolds alone that can maximize the results keep in mind a great deal of what you can expect to gain from use of headers is dependent on having the exhaust headers tuned to scavenge the cylinders and thats dependent on both the header primary length , diameter,and collectors length and diameter,being correctly matched to the engines displacement, compression and cam timing, and having an exhaust system that has LESS than 1 PSI in back pressure, the best headers in the world feeding into an exhaust system with significant back pressure will result in little gains if any over a rams horn manifold.Id also point out that when you see a dyno torque curve on a 383 sbc like that that falls rapidly from only 3500rpm, the cam used was very obviously too low in duration for the application and/or the exhaust was restrictive and hurting power (probably the case here) because theres a rapid drop in torque as the engine rpms build , thats almost always an indicator of a restricted air flow rate, it can be because the cams not allowing the intake ports to flow to their full potential but it can be because as the rpms build so does the volume of exhaust gases which increases the effect of any restricted exhaust, because of the rapid build-up in back pressure

vechart.gif


vef1.jpg


your engines torque curve is almost always a good indication of the engine volumetric efficiency
Chevy Exhaust Manifolds Casting Numbers
Use these casting numbers to identify the exhaust manifolds you have.

Casting Number Years Engine Side Comments
336706 74-78 350 RH
336707 74-78 350 LH
336708 74-78 350 RH
336709 74-78 350 RH Camaro & Z-28 with A.I.R.
336710 74-78 307, 350 & 400 LH Chevelle,Camaro,Z-28,Nova and Passenger with A.I.R.
346222 74-80 307, 350 & 400 RH Chevelle,Camaro, Nova and Passenger with A.I.R.
346247 75-77 262, 350&400 LH Chevelle,Camaro Monte Carlo and Passenger 110,145,155,175HP 346248 75-77 262, 350&400 RH Chevelle,Camaro, Monte Carlo and Passenger 110,145,155,175 HP
354432 75-76 262 RH 110 HP
354433 75-76 262 LH 110 HP
364753 76-80 307, 350 & 400 LH Camaro, Monte Carlo, Malibu and Passenger
372243 74-83 307, 350 & 400 RH Corvette and Replacement manifold
462697 77-79 267 & 305 LH Monte Carlo and Malibu
462698 77-83 267 & 305 RH Monte Carlo and Malibu
474008 78-82 267, 305 & 350 RH
745994 80-86 267 & 305 LH
3704791 55-56 265 LH Corvette and Passenger 195 HP
3704792 55-56 265 RH Corvette and Passenger 195 HP
3725563 56 265 LH & RH Corvette and Passenger 210 HP 2-Bolt Flange
3731557 56 265 LH Corvette and Passenger 225 HP
3731558 56 265 RH Corvette and Passenger 225 HP
3732498 58 283 RH Corvette FI
3733975 57 283 LH Corvette and Passenger 220, 245, 250, 270 & 283 HP
3733976 57 283 RH Corvette and Passenger 220, 245, 250, 270 & 283 HP
3737902 62-65 327 RH 300, 340, 360, 365 & 375 HP 2.5" Outlet
3746563 65 327 LH 300 HP
3747038 58-65 283 & 327 RH Corvette and Passenger 220, 250 & 300 HP 1.9" Outlet
3747042 58-68 283, 307 & 327 RH Corvette and Passenger 195, 200, 220, 250, 270, 275, 290, 300 & 350 HP 1.9" Outlet
3747938 64 327 LH & RH 250 & 300 HP
3747942 65 327 LH & RH 250, 350 & 365 HP
3749965 58-63 283 & 327 LH Corvette and Passenger 230,245,250,270,275,290,300 & 315 HP
3750556 58-65 283 & 327 RH Corvette and Passenger 230,245 250,270,275,290,300 & 315 HP
3780728 64-67 327 LH Chevy II
3790729 64-67 283 & 327 LH 195, 220, 250, 270, 275, 300 & 350 HP 2.0" Outlet Chevy II
3790730 64-65 283 & 327 RH 220, 250 & 300 HP 1.9" Outlet Chevy II
3791162 65-66 283 & 327 RH Chevy II with AC
3791182 66-67 283 & 327 RH Passenger with AC
3797901 62-63 327 LH Corvette 300, 340 & 360 HP
3797902 62-65 327 RH Corvette 300, 340, 360, 365 & 375 HP 2.5" Outlet
3797942 63-65 327 LH & RH Corvette 300, 360, 365 & 375 HP 2.5" Outlet
3834947 64-68 283, 307 & 327 LH Chevelle 195, 200, 210, 220, 250, 275, 295, 300, 325, 350 & 365 HP 2.0" Outlet
3836968 55-56 265 RH Corvette and Passenger 195 HP
3837069 55 265 LH Corvette and Passenger 195 HP
3840715 64 283 & 327 LH Chevelle
3840912 64-68 283, 307, 327 & 350 RH Chevelle, Camaro and Nova 195, 200, 210, 220, 250, 275, 295, 300, 325, 350 & 365 HP 1.9" Outlet
3846559 64-71 327 & 350 LH Corvette 250, 270, 300 & 350 HP 2.0" Outlet
3846563 64-65 327 LH Corvette 300, 350 & 365 HP 2.5" Outlet
3846659 66 327 LH 350 HP
3849288 64-67 283 & 327 RH 195, 220, 275 & 350 HP 1.9" Outlet Chevy II
3849290 64-67 283 & 327 RH 195, 220, 275 & 350 HP 1.9" Outlet Chevy II with AC
3855163 65-68 283, 307 & 327 LH Passenger and Truck 195, 200,220,250 & 275 HP 2.0" Outlet
3872723 66-67 283 & 327 LH 195, 220, 275 & 350 HP 2.0" Outlet Chevy II A.I.R.
3872729 66 283 & 327 LH Chevelle 195,220, 275 & 350 HP 2.0" Outlet A.I.R.
3872730 66-68 283, 302, 307 & 327 RH Chevelle, Camaro & Z-28 200, 210, 220, 250, 275, 290, 325 & 350 HP 1.9" Outlet A.I.R.
3872738 66-67 283 & 327 RH 195, 220, 275 & 350 HP 1.9" Outlet Chevy II
3872741 66-68 283, 307 & 327 LH Passenger 195, 200, 220, 250 & 275 HP 2.0" Outlet A.I.R.
3872765 67-71 327 & 350 LH Corvette 300, 330, 350 & 370 HP 2.0" Outlet A.I.R.
3872778 66-68 283, 307 & 327 RH Corvette, Passenger and Truck 195, 200, 250, 275, 300 & 350 HP 1.9" Outlet A.I.R.
3887186 66 283 RH 220 HP 1.9" Outlet
3890424 64-67 283 & 327 RH Chevy II
3892679 66-68 283, 302, 307, 327 & 350 LH Chevelle, Camaro and Z-28 195, 200, 210, 220, 250, 275, 290, 295 & 325 HP 2.0" Outlet
3892683 66-68 283, 302, 307, 327 & 350 LH Chevelle, Camaro and Z-28 195, 200, 210, 220, 250, 275, 290, 295 & 325 HP 2.0" Outlet
3893604 66-68 283 & 327 RH Passenger A.I.R.
3893608 67-68 283, 302, 307, 327 & 350 RH Chevelle, Camaro and Z-28 195, 200, 210, 250, 275, 290, 295 & 325 HP 1.9" Outlet
3896956 67-68 283 & 327 RH Truck
3905364 69-72 307, 350 & 400 RH Truck
3932376 69-70 307, 327, 350 & 400 RH Chevelle and Camaro 200, 210, 250, 255, 265 & 300 HP 1.9" Outlet
3932461 69-74 327 & 350 LH & RH Corvette 190, 195, 200, 235, 255, 300, 330 & 350 HP 1.9" Outlet A.I.R.
3932465 69-70 327, 350 & 400 RH Passenger 235, 250, 255, 265, 300 & 350 HP 1.9" Outlet
3932469 69-70 327 & 350 LH Passenger 235, 250, 255 & 300 HP 2.0" Outlet
3932473 69-70 327, 350 & 400 LH Passenger 235, 250, 255, 265 & 300 HP 2.0" Outlet
3932481 69 350 RH Corvette
3940972 67 350 RH Camaro 295 HP
3942527 69-70 302, 307, 327 & 350 LH Chevelle, Camaro, Z-28 and Nova 200, 210, 250, 255, 290, 300 & 360 HP 2.0" Outlet A.I.R.
3942529 69-70 302, 307, 327, 350 & 400 LH Chevelle, Camaro and Nova 200, 210, 250, 255, 290 & 300 HP 2.0" Outlet
3946826 69-70 302, 307, 327 & 350 RH Chevelle, Camaro, Z-28 and Nova200, 210, 250, 255, 290, 300 & 360 HP 1.9" Outlet A.I.R.
3959562 72-74 307, 350 & 400 RH Chevelle, Camaro and Z-28 115, 130, 145, 150, 160, 165, 170, 175, 180, 185 & 245 HP 2.0" Outlet A.I.R.
3973432 70-74 307, 350 & 400 RH Chevelle, Camaro, Nova and Passenger 115, 130, 150, 165, 170, 175, 180, 200, 245, 250, 255, 270 & 300 HP 2.0" Outlet
3986330 69-73 302, 307, 327 & 350 RH Camaro and Z-28 200, 210, 245, 250, 255, 290, 300, 330 & 360 HP 1.9" Outlet A.I.R.
3989036 71-75 350 LH & RH Corvette and Passenger 165, 195, 200, 205 & 270 HP 2.0" Outlet with and without A.I.R.
3989041 69-74 302, 307, 327, 350 & 400 LH Camaro, Z-28 and Nova 115, 130, 145, 150, 160, 165, 170, 180, 185, 200, 210, 245, 250, 255, 290, 300, 330 & 360 HP 2.0" Outlet with and without A.I.R.
3989043 70-73 307, 350 & 400 LH Chevelle, Camaro, Nova and Passenger 105, 115, 130, 145, 150, 165, 175, 185, 200, 245, 250, 255, 270 & 300 HP 2.0" Outlet with and without A.I.R.
3989055 69-72 307, 350 & 400 LH
3997742 71-78 307 & 350 RH 2.0" Outlet
3998902 72-78 307 & 350 RH
10045315 88-94 305 & 350 LH
10045317 88-94 305 & 350 LH
10045317 88-94 305 & 350 LH
10046123 87-92 305 & 350 LH
10046139 84-85 350 LH
10046140 84-85 350 RH
10055734 87-91 350 RH
10092901 89-91 350 LH
10092903 89-94 350 LH
10092905 89-94 350 LH
10108437 87-93 305 & 350 RH
10128448 91-93 305 & 350 LH
10128483 91-93 305 & 350 LH
10166144 91-94 350 RH
10166145 87-90 305 & 350 LH
10166147 89-94 305 & 350 LH
10166158 89-94 305 & 350 RH
10168494 94 265 & 350 LH
10207656 93-94 350 LH
10207657 93 350 RH
10433037 82-86 305 LH
12550621 94 265 RH
12550622 91 350 RH
14007400 80-86 267 & 305 LH
14014437 80-84 305 LH
14014438 80-84 305 RH
14014459 81-86 305 & 350 LH
14014500 79-86 267, 305 & 350 RH
14022625 80-81 305 LH
14031361 82-86 305 RH
14031376 81-86 350 RH
14034069 81-86 350 RH
14034075 81-86 305 & 350 LH
14043373 82-86 305 LH
14050233 83-86 305 & 350 LH
14050282 83-87 305 & 350 RH
14050287 82-86 305 LH
14057029 84-85 350 LH
14057030 84-85 350 RH
14060630 81-86 350 RH
14060633 81-86 305 & 350 LH
14067365 77-86 267, 305, 350 & 400 LH
14068667 85-88 350 LH
14068670 85-88 350 RH
14071200 83-86 305 RH
14075611 83-86 305 LH
14079295 85-86 305 & 350 LH
14079296 85-86 305 & 350 RH
14087511 86-91 350 LH
14087512 86-91 350 RH
14093653 87-90 305 & 350 LH
14093654 87-90 305 & 350 RH
14093655 87-90 305 & 350 LH
14093658 88-94 305 & 350 RH
14093660 87-90 305 & 350 RH
14093682 87-90 305 & 350 RH
14094045 87-90 305 & 350 LH
14094063 87-92 305 & 350 LH
14094064 87-92 305 & 350 RH
14094065 85-88 350 RH
14101054 87-88 305 & 350 RH
14102016 88-94 305 & 350 RH
14102018 89-94 305 & 350 RH
14103206 87-91 305 & 350 RH
14103207 87-91 305 & 350 LH
329225 73-76 454 LH Chevelle and Passenger with and without A.I.R.
353028 73-76 454 LH Chevelle and Passenger with and without A.I.R.
353030 73-76 454 LH Police
3732793 58-61 348 LH Passenger
3732794 58-61 348 RH Passenger
3767583 59-61 348 & 409 LH Passenger
3767584 59-61 348 & 409 RH Passenger
3814682 62-64 409 RH Passenger
3814683 62-64 409 LH Passenger
3822925 62-64 409 LH Passenger & Z-11
3822926 62-64 409 RH Passenger & Z-11
3855161 65 409 LH Passenger 340 & 400 HP
3855162 65 409 RH Passenger 340 & 400 HP
3856297 65 396 LH 325 HP
3856301 65 396 LH 425 HP Corvette
3856302 65 396 RH 425 HP Corvette
3856306 65 396 RH Passenger 325 HP
3857297 65 396 LH Passenger 325 HP
3868874 65-66 396 RH Chevelle 325, 360 & 375 HP Z-16
3869925 65 396 LH Chevelle 375 HP Z-16
3872770 66 396 RH
3880827 66-69 427 & 454 LH Corvette
3880828 66-72 427 & 454 RH Corvette 270,365,390 &425 HP with and without A.I.R. LS-5 & LS-6
3880869 70-72 454 LH Corvette 365 & 425 HP with and without A.I.R. LS-5 & LS-6
3883827 66 427 LH Passenger
3883828 66 427 RH Passenger
3883999 66 396 LH Chevelle 325, 360 & 375 HP
3884504 66-67 396 & 427 RH Passenger 325, 385 & 390 HP
3892307 66-67 396 & 427 LH Passenger 325 & 390 HP
3902401 67 396 LH Chevelle
3904399 66 396 LH
3909879 67-70 396, 427 & 454 LH Chevelle, Camaro and Nova 325, 350, 375, 425, 430 & 450 HP LS-6 COPO
3909880 67 396 RH Chevelle and Camaro 325, 350 & 375 HP
3914613 68-70 396 & 427 LH Passenger 265, 325, 335, 345, 390 & 425 HP
3916178 68-70 396, 427 & 454 RH Chevelle, Camaro, Nova and Passenger 325, 350, 375, 425, 430 & 450 HP COPO LS-5 & LS-6
3969869 70-74 454 LH Corvette 270, 365 & 390 HP with and without A.I.R. LS-5
3989310 71-72 402 & 454 RH Chevelle, Camaro, Monte Carlo and Passenger
3989343 71-72 402 & 454 LH Chevelle, Camaro, Monte Carlo and Passenger
3994045 73-75 454 LH Police


viewtopic.php?f=56&t=495

viewtopic.php?f=56&t=1166

viewtopic.php?f=56&t=961

viewtopic.php?f=56&t=3155

viewtopic.php?f=56&t=1303
 
Last edited by a moderator:

59Lenoir

Well-Known Member



so would it be worthwhile to put these on an otherwise stock 283/2bbl with soon-to-be-dual exhaust? There is a possibility of future cam/head/carb enhancment.
 
Last edited by a moderator:

grumpyvette

Administrator
Staff member
http://www.speedwaymotors.com/Dorman-25 ... ,9133.html

why not pay a good deal less, they are better than most stock manifolds but you can find cheap headers that still work reasonably well for under $250

https://www.chevellestuff.net/qd/exhaust_casting_by_year.htm

https://www.ss396.com/part/AXD-396.html

http://emwexhaustmanifold.com/gm.htm

https://www.chevydiy.com/sourcing-and-selecting-chevy-big-block-exhaust-manifolds/

https://www.nastyz28.com/bbcmenu.php


BBC Exhaust Manifold Casting Numbers
Cast # Years Side CID Applications
329225 1973-76 LH 454
353028 1973-76 LH 454
353030 1973-76 LH 454 police
3856297 1965 LH 396 325
3856301 1965 LH 396 425 Corvette
3856302 1965 RH 396 425 Corvette
3856306 1965 RH 396 325
3857297 1965 LH 396 325
3868874 1965-66 RH 396 325, 360, 375 Z-16
3869925 1965 LH 396 375 Z-16
3872770 1966 RH 396
3880827 1966-69 LH 427/454 Corvette
3880828 1966-72 RH 427/454 Corvette
3880869 1970-72 LH 454 Corvette
3883999 1966 LH 396 325, 360, 375
3884504 1966-67 RH 396/427 325, 385, 390
3892307 1966-67 LH 396/427 325, 390
3902401 1967 LH 396
3904399 1966 LH 396
3909879 1967-70 LH 396/427 COPO/454 325, 350, 375, 425, 430
3909880 1967 RH 396 325, 350, 375
3914613 1968-70 LH 396/427 265, 325, 335, 345, 390, 425
3916178 1968-70 RH 396/427 COPO/454 325, 350, 375, 425, 430
3969869 1970-74 LH 454 Corvette
3989310 1971-72 RH 402/454
3989343 1971-72 LH 402/454
3994045 1973-75 LH 454


BBC Exhaust Manifold Casting Numbers
Cast # Years Side CID Applications
329225 1973-76 LH 454
353028 1973-76 LH 454
353030 1973-76 LH 454 police
3856297 1965 LH 396 325
3856301 1965 LH 396 425 Corvette
3856302 1965 RH 396 425 Corvette
3856306 1965 RH 396 325
3857297 1965 LH 396 325
3868874 1965-66 RH 396 325, 360, 375 Z-16
3869925 1965 LH 396 375 Z-16
3872770 1966 RH 396
3880827 1966-69 LH 427/454 Corvette
3880828 1966-72 RH 427/454 Corvette
3880869 1970-72 LH 454 Corvette
3883999 1966 LH 396 325, 360, 375
3884504 1966-67 RH 396/427 325, 385, 390
3892307 1966-67 LH 396/427 325, 390
3902401 1967 LH 396
3904399 1966 LH 396
3909879 1967-70 LH 396/427 COPO/454 325, 350, 375, 425, 430
3909880 1967 RH 396 325, 350, 375
3914613 1968-70 LH 396/427 265, 325, 335, 345, 390, 425
3916178 1968-70 RH 396/427 COPO/454 325, 350, 375, 425, 430
3969869 1970-74 LH 454 Corvette
3989310 1971-72 RH 402/454
3989343 1971-72 LH 402/454
3994045 1973-75 LH 454
 
Last edited by a moderator:

59Lenoir

Well-Known Member
wow! thats a lot cheaper! Probably less that the cost of sandblastingg my originals! Thanks
not to sound like a "numbers-matching-weenie" but aren't these slightly differetn than my originals?
 

grumpyvette

Administrator
Staff member
they might be , I don,t know what they look like other than the picture and Id have to put them next to your originals and compare them, but at the price it seems like a decent deal

THERE ARE STAINLESS BLOCK HUGGER HEADERS
http://www.kmjent.com/cart/product.php?productid=564

http://www.ecklerscorvette.com/corvette ... -1974.html
bbcman.jpg

Exhaust Manifold ID
http://outintheshop.com/faq/casting/exhaust_man.html
SEARCH cast numbers

Use these casting numbers to identify the exhaust manifolds you have.



Chevy Exhaust Manifolds Casting Numbers
Use these casting numbers to identify the exhaust manifolds you have.

Casting Number Years Engine Side Comments
336706 74-78 350 RH
336707 74-78 350 LH
336708 74-78 350 RH
336709 74-78 350 RH Camaro & Z-28 with A.I.R.
336710 74-78 307, 350 & 400 LH Chevelle,Camaro,Z-28,Nova and Passenger with A.I.R.
346222 74-80 307, 350 & 400 RH Chevelle,Camaro, Nova and Passenger with A.I.R.
346247 75-77 262, 350&400 LH Chevelle,Camaro Monte Carlo and Passenger 110,145,155,175HP 346248 75-77 262, 350&400 RH Chevelle,Camaro, Monte Carlo and Passenger 110,145,155,175 HP
354432 75-76 262 RH 110 HP
354433 75-76 262 LH 110 HP
364753 76-80 307, 350 & 400 LH Camaro, Monte Carlo, Malibu and Passenger
372243 74-83 307, 350 & 400 RH Corvette and Replacement manifold
462697 77-79 267 & 305 LH Monte Carlo and Malibu
462698 77-83 267 & 305 RH Monte Carlo and Malibu
474008 78-82 267, 305 & 350 RH
745994 80-86 267 & 305 LH
3704791 55-56 265 LH Corvette and Passenger 195 HP
3704792 55-56 265 RH Corvette and Passenger 195 HP
3725563 56 265 LH & RH Corvette and Passenger 210 HP 2-Bolt Flange
3731557 56 265 LH Corvette and Passenger 225 HP
3731558 56 265 RH Corvette and Passenger 225 HP
3732498 58 283 RH Corvette FI
3733975 57 283 LH Corvette and Passenger 220, 245, 250, 270 & 283 HP
3733976 57 283 RH Corvette and Passenger 220, 245, 250, 270 & 283 HP
3737902 62-65 327 RH 300, 340, 360, 365 & 375 HP 2.5" Outlet
3746563 65 327 LH 300 HP
3747038 58-65 283 & 327 RH Corvette and Passenger 220, 250 & 300 HP 1.9" Outlet
3747042 58-68 283, 307 & 327 RH Corvette and Passenger 195, 200, 220, 250, 270, 275, 290, 300 & 350 HP 1.9" Outlet
3747938 64 327 LH & RH 250 & 300 HP
3747942 65 327 LH & RH 250, 350 & 365 HP
3749965 58-63 283 & 327 LH Corvette and Passenger 230,245,250,270,275,290,300 & 315 HP
3750556 58-65 283 & 327 RH Corvette and Passenger 230,245 250,270,275,290,300 & 315 HP
3780728 64-67 327 LH Chevy II
3790729 64-67 283 & 327 LH 195, 220, 250, 270, 275, 300 & 350 HP 2.0" Outlet Chevy II
3790730 64-65 283 & 327 RH 220, 250 & 300 HP 1.9" Outlet Chevy II
3791162 65-66 283 & 327 RH Chevy II with AC
3791182 66-67 283 & 327 RH Passenger with AC
3797901 62-63 327 LH Corvette 300, 340 & 360 HP
3797902 62-65 327 RH Corvette 300, 340, 360, 365 & 375 HP 2.5" Outlet
3797942 63-65 327 LH & RH Corvette 300, 360, 365 & 375 HP 2.5" Outlet
3834947 64-68 283, 307 & 327 LH Chevelle 195, 200, 210, 220, 250, 275, 295, 300, 325, 350 & 365 HP 2.0" Outlet
3836968 55-56 265 RH Corvette and Passenger 195 HP
3837069 55 265 LH Corvette and Passenger 195 HP
3840715 64 283 & 327 LH Chevelle
3840912 64-68 283, 307, 327 & 350 RH Chevelle, Camaro and Nova 195, 200, 210, 220, 250, 275, 295, 300, 325, 350 & 365 HP 1.9" Outlet
3846559 64-71 327 & 350 LH Corvette 250, 270, 300 & 350 HP 2.0" Outlet
3846563 64-65 327 LH Corvette 300, 350 & 365 HP 2.5" Outlet
3846659 66 327 LH 350 HP
3849288 64-67 283 & 327 RH 195, 220, 275 & 350 HP 1.9" Outlet Chevy II
3849290 64-67 283 & 327 RH 195, 220, 275 & 350 HP 1.9" Outlet Chevy II with AC
3855163 65-68 283, 307 & 327 LH Passenger and Truck 195, 200,220,250 & 275 HP 2.0" Outlet
3872723 66-67 283 & 327 LH 195, 220, 275 & 350 HP 2.0" Outlet Chevy II A.I.R.
3872729 66 283 & 327 LH Chevelle 195,220, 275 & 350 HP 2.0" Outlet A.I.R.
3872730 66-68 283, 302, 307 & 327 RH Chevelle, Camaro & Z-28 200, 210, 220, 250, 275, 290, 325 & 350 HP 1.9" Outlet A.I.R.
3872738 66-67 283 & 327 RH 195, 220, 275 & 350 HP 1.9" Outlet Chevy II
3872741 66-68 283, 307 & 327 LH Passenger 195, 200, 220, 250 & 275 HP 2.0" Outlet A.I.R.
3872765 67-71 327 & 350 LH Corvette 300, 330, 350 & 370 HP 2.0" Outlet A.I.R.
3872778 66-68 283, 307 & 327 RH Corvette, Passenger and Truck 195, 200, 250, 275, 300 & 350 HP 1.9" Outlet A.I.R.
3887186 66 283 RH 220 HP 1.9" Outlet
3890424 64-67 283 & 327 RH Chevy II
3892679 66-68 283, 302, 307, 327 & 350 LH Chevelle, Camaro and Z-28 195, 200, 210, 220, 250, 275, 290, 295 & 325 HP 2.0" Outlet
3892683 66-68 283, 302, 307, 327 & 350 LH Chevelle, Camaro and Z-28 195, 200, 210, 220, 250, 275, 290, 295 & 325 HP 2.0" Outlet
3893604 66-68 283 & 327 RH Passenger A.I.R.
3893608 67-68 283, 302, 307, 327 & 350 RH Chevelle, Camaro and Z-28 195, 200, 210, 250, 275, 290, 295 & 325 HP 1.9" Outlet
3896956 67-68 283 & 327 RH Truck
3905364 69-72 307, 350 & 400 RH Truck
3932376 69-70 307, 327, 350 & 400 RH Chevelle and Camaro 200, 210, 250, 255, 265 & 300 HP 1.9" Outlet
3932461 69-74 327 & 350 LH & RH Corvette 190, 195, 200, 235, 255, 300, 330 & 350 HP 1.9" Outlet A.I.R.
3932465 69-70 327, 350 & 400 RH Passenger 235, 250, 255, 265, 300 & 350 HP 1.9" Outlet
3932469 69-70 327 & 350 LH Passenger 235, 250, 255 & 300 HP 2.0" Outlet
3932473 69-70 327, 350 & 400 LH Passenger 235, 250, 255, 265 & 300 HP 2.0" Outlet
3932481 69 350 RH Corvette
3940972 67 350 RH Camaro 295 HP
3942527 69-70 302, 307, 327 & 350 LH Chevelle, Camaro, Z-28 and Nova 200, 210, 250, 255, 290, 300 & 360 HP 2.0" Outlet A.I.R.
3942529 69-70 302, 307, 327, 350 & 400 LH Chevelle, Camaro and Nova 200, 210, 250, 255, 290 & 300 HP 2.0" Outlet
3946826 69-70 302, 307, 327 & 350 RH Chevelle, Camaro, Z-28 and Nova200, 210, 250, 255, 290, 300 & 360 HP 1.9" Outlet A.I.R.
3959562 72-74 307, 350 & 400 RH Chevelle, Camaro and Z-28 115, 130, 145, 150, 160, 165, 170, 175, 180, 185 & 245 HP 2.0" Outlet A.I.R.
3973432 70-74 307, 350 & 400 RH Chevelle, Camaro, Nova and Passenger 115, 130, 150, 165, 170, 175, 180, 200, 245, 250, 255, 270 & 300 HP 2.0" Outlet
3986330 69-73 302, 307, 327 & 350 RH Camaro and Z-28 200, 210, 245, 250, 255, 290, 300, 330 & 360 HP 1.9" Outlet A.I.R.
3989036 71-75 350 LH & RH Corvette and Passenger 165, 195, 200, 205 & 270 HP 2.0" Outlet with and without A.I.R.
3989041 69-74 302, 307, 327, 350 & 400 LH Camaro, Z-28 and Nova 115, 130, 145, 150, 160, 165, 170, 180, 185, 200, 210, 245, 250, 255, 290, 300, 330 & 360 HP 2.0" Outlet with and without A.I.R.
3989043 70-73 307, 350 & 400 LH Chevelle, Camaro, Nova and Passenger 105, 115, 130, 145, 150, 165, 175, 185, 200, 245, 250, 255, 270 & 300 HP 2.0" Outlet with and without A.I.R.
3989055 69-72 307, 350 & 400 LH
3997742 71-78 307 & 350 RH 2.0" Outlet
3998902 72-78 307 & 350 RH
10045315 88-94 305 & 350 LH
10045317 88-94 305 & 350 LH
10045317 88-94 305 & 350 LH
10046123 87-92 305 & 350 LH
10046139 84-85 350 LH
10046140 84-85 350 RH
10055734 87-91 350 RH
10092901 89-91 350 LH
10092903 89-94 350 LH
10092905 89-94 350 LH
10108437 87-93 305 & 350 RH
10128448 91-93 305 & 350 LH
10128483 91-93 305 & 350 LH
10166144 91-94 350 RH
10166145 87-90 305 & 350 LH
10166147 89-94 305 & 350 LH
10166158 89-94 305 & 350 RH
10168494 94 265 & 350 LH
10207656 93-94 350 LH
10207657 93 350 RH
10433037 82-86 305 LH
12550621 94 265 RH
12550622 91 350 RH
14007400 80-86 267 & 305 LH
14014437 80-84 305 LH
14014438 80-84 305 RH
14014459 81-86 305 & 350 LH
14014500 79-86 267, 305 & 350 RH
14022625 80-81 305 LH
14031361 82-86 305 RH
14031376 81-86 350 RH
14034069 81-86 350 RH
14034075 81-86 305 & 350 LH
14043373 82-86 305 LH
14050233 83-86 305 & 350 LH
14050282 83-87 305 & 350 RH
14050287 82-86 305 LH
14057029 84-85 350 LH
14057030 84-85 350 RH
14060630 81-86 350 RH
14060633 81-86 305 & 350 LH
14067365 77-86 267, 305, 350 & 400 LH
14068667 85-88 350 LH
14068670 85-88 350 RH
14071200 83-86 305 RH
14075611 83-86 305 LH
14079295 85-86 305 & 350 LH
14079296 85-86 305 & 350 RH
14087511 86-91 350 LH
14087512 86-91 350 RH
14093653 87-90 305 & 350 LH
14093654 87-90 305 & 350 RH
14093655 87-90 305 & 350 LH
14093658 88-94 305 & 350 RH
14093660 87-90 305 & 350 RH
14093682 87-90 305 & 350 RH
14094045 87-90 305 & 350 LH
14094063 87-92 305 & 350 LH
14094064 87-92 305 & 350 RH
14094065 85-88 350 RH
14101054 87-88 305 & 350 RH
14102016 88-94 305 & 350 RH
14102018 89-94 305 & 350 RH
14103206 87-91 305 & 350 RH
14103207 87-91 305 & 350 LH
329225 73-76 454 LH Chevelle and Passenger with and without A.I.R.
353028 73-76 454 LH Chevelle and Passenger with and without A.I.R.
353030 73-76 454 LH Police
3732793 58-61 348 LH Passenger
3732794 58-61 348 RH Passenger
3767583 59-61 348 & 409 LH Passenger
3767584 59-61 348 & 409 RH Passenger
3814682 62-64 409 RH Passenger
3814683 62-64 409 LH Passenger
3822925 62-64 409 LH Passenger & Z-11
3822926 62-64 409 RH Passenger & Z-11
3855161 65 409 LH Passenger 340 & 400 HP
3855162 65 409 RH Passenger 340 & 400 HP
3856297 65 396 LH 325 HP
3856301 65 396 LH 425 HP Corvette
3856302 65 396 RH 425 HP Corvette
3856306 65 396 RH Passenger 325 HP
3857297 65 396 LH Passenger 325 HP
3868874 65-66 396 RH Chevelle 325, 360 & 375 HP Z-16
3869925 65 396 LH Chevelle 375 HP Z-16
3872770 66 396 RH
3880827 66-69 427 & 454 LH Corvette
3880828 66-72 427 & 454 RH Corvette 270,365,390 &425 HP with and without A.I.R. LS-5 & LS-6
3880869 70-72 454 LH Corvette 365 & 425 HP with and without A.I.R. LS-5 & LS-6
3883827 66 427 LH Passenger
3883828 66 427 RH Passenger
3883999 66 396 LH Chevelle 325, 360 & 375 HP
3884504 66-67 396 & 427 RH Passenger 325, 385 & 390 HP
3892307 66-67 396 & 427 LH Passenger 325 & 390 HP
3902401 67 396 LH Chevelle
3904399 66 396 LH
3909879 67-70 396, 427 & 454 LH Chevelle, Camaro and Nova 325, 350, 375, 425, 430 & 450 HP LS-6 COPO
3909880 67 396 RH Chevelle and Camaro 325, 350 & 375 HP
3914613 68-70 396 & 427 LH Passenger 265, 325, 335, 345, 390 & 425 HP
3916178 68-70 396, 427 & 454 RH Chevelle, Camaro, Nova and Passenger 325, 350, 375, 425, 430 & 450 HP COPO LS-5 & LS-6
3969869 70-74 454 LH Corvette 270, 365 & 390 HP with and without A.I.R. LS-5
3989310 71-72 402 & 454 RH Chevelle, Camaro, Monte Carlo and Passenger
3989343 71-72 402 & 454 LH Chevelle, Camaro, Monte Carlo and Passenger
3994045 73-75 454 LH Police


keep in mind the big block chevy also had some preferred exhaust manifold casting designs
 
Last edited by a moderator:
B

bob

Guest
why run rams horn exhaust when headers are both fairly cheap and produce better results?? just asking, curious?
 

59Lenoir

Well-Known Member
I'm trying to keep things relatively stock-looking under the hood, even if it's at the expense of power; I'm not really looking for a hot rod, just 'a little better' than stock if possible.
Also, aren't you more likely to be plagued by hot-start problems with headers?
 

grumpyvette

Administrator
Staff member
http://www.powerblocktv.com/episodes/HP ... mance-mods

you might find this interesting

AND for anyone who thinks headers are not an important component in your engines efficiency ,heres a rather interesting dyno test where carefully ported rams horn type exhaust manifolds were tested against a set of 1 3/4" headers, the result with this particular engine combo was that the engine made just over 500 hp with headers but LOST 95 hp once the cast exhaust manifolds were installed replacing the headers


http://www.yenko.net/ubbthreads/ubbthre ... /415017/16

Pull17.jpg


THERE IT IS!!! 504 HP @ 7400 rpm! That was my goal with headers, and once I realized we were off quite a bit on the camshaft I was pretty doubtful we would see it. Again, keep in mind the cam in this engine as supposed to be designed to run with ported exhaust manifolds, and was to have a "stock" idle. The idle went out the window as soon as the engine fired for the first time, and w/o giving away any camshaft details, the LSA on this cam has been a concern to me since I received it, but I was placing my trust in someone else's expertise. It's not a big issue, I didn't expect them to hit a bulls-eye the first time around, that's all part of the deal when building engines like this.

Now that we'd hit my power goal with the headers, it was time to try the manifolds.

As much as it pains me to say this, as I feared once I realized the cam wasn't right, the manifold test was a bust. The engine flat-out HATED the manifolds...it lost 95 horsepower with the manifolds installed. eek However, even though the engine was obviously unhappy with the manifolds, peak power still came in @ 7200 rpm. As such, that will have to be re-tested during the next round of testing.

504 HP from 306" is just under 1.68 HP/CI, and 397 lb.ft of torque is 1.29 lb/CI. That's pretty stout considering how much there is still left on the table with this build.

Last comments regarding the dyno sheets: This time the air/fuel ratios are correct, but the VE figures are nowhere close. I calculated VE using Pipemax software and it showed roughly 94% VE to match the actual dyno numbers.

So that's it for now on this build, but rest assured, there will be more to come! Along those lines, I'd like to hear what you would like to see me do with this engine project--stick with the "F.A.S.T." theme?...go balls-out with headers?...tame it down a little with a more "practical" set of heads and cam?
 
8

87vette81big

Guest
Grumpy something just don't look right with the above Water Brake Engine Dyno sheet printout.
Volumemetric efficiency never exceeded 77.6%.
An engine making 1.68 Hp per cubic inch of 306ci peaking Hp @ 7400Rpms & 504 Hp & headers should have VE ar least 90-95%.
Data appears skewed.
Left alot in the table.
Small CFM carb used ?
 
8

87vette81big

Guest
Yes I read the notations Grumpy.

Old dyno test from '99.
Interesting writeup none the less.
 
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