porting the aftermarket TPI (Z51l9889 posted much of this)

grumpyvette

Administrator
Staff member
(Z51l9889 posted much of this)
viewtopic.php?f=55&t=1509&p=3459&hilit=base+runner+plenum#p3459

http://www.firstfuelinjection.com/products.htm

"I've begun porting my FIRST intake for my 383 build. I will be gasket matching the base to a FelPro 1205 and opening up the base and runners such that the passage tapers from the inlet at the plenum to the minimum area at the intake manifold exit.

Here are some pictures of the intake parts before porting and my initial (very) rough-in of the first runner. As the pictures show, I've got a fair amount of material to remove, but these things have plenty of meat for porting. To give an idea of the size, the wooden balls shown in the porting pictures are 1.75" in diameter. A stock TPI base and runners have a diameter of 1.47". The goal is to get the runners sized to pass a 1.875" ball through the runner all the way into the manifold where the shape transitions to a rectangle. I'm at about 1.86" now -- I'm sneaking up on it so I don't break through.

I'll post more progress pics as I go. Enjoy. :cheers:


P1010007.jpg

P1010008.jpg

P1010019.jpg

P1010016.jpg

P1010023.jpg

P1010012.jpg

P1010013.jpg

P1010010.jpg

P1010003.jpg

P1010007a.jpg
"


Ok Im impressed with the work done, pictures, in the thread, etc, but
IM kind of sceptical of the benefits of porting the runners & plenum past the point where they flow equal too or only slightly more than the cylinder head ports, as its been my experiance that porting past that point tends to lower port velocity and reduce volumetric efficiency.

the 1206 intake gasket port is 2.150" x 1.2"=2.58 sq inches
the 1205 intake gasket port is 2.00" x 1.18"=2.36 sq inches

a round port of 1.75"=2.40 sq inches
a round port of 1.86"=2.72 sq inches

BTW READ THRU THIS

http://ncarboni.home.att.net/NCtpi.html


see the potential for a problem, youll port your runners past the point where the extra cross sectional area benefits the port flow rates and velocities will drop, off resulting in at least no benefits, from the additional porting, and at worst a reduction in flow and a tendency to have turbulance disrupting the air stream. now IM NOT saying your not going to have a huge improvement over a stock TPI intake , but at some point further port increases are counter productive.
 
Re: porting the aftermarket TPI (Z51l9889 posted much of thi

the runner LENGTH has a strong effect on the engines most efficient rpm band but the,runners cross sectional area and air flow rates, engine displacement, compression ratio and both intake and cylinder head flow numbers and cam timing have a huge effect on the engines power potential , keep in mind that you want to maintain the cars approximate original power band so the cars rear gearing and stall speed are still compatible,[/COLOR] swapping too a miniram or a stealthram produces more peak hp, but at the expense of some off idle torque, NOT so much because the intakes runners are shorter but because they flow more and you can reach higher in the rpm band, while still filling the cylinders efficiently due to the higher flow rates.
now that might sound a bit confusing so lets look at how you rate hp
the formula for hp is engine torque times engine rpm divided by 5252= horsepower

so lets say your stock tpi puts out gross 230hp

http://www.stingray.nu/tips/tech85.htm

viewtopic.php?f=55&t=1509
I think this may help

http://www.wallaceracing.com/Calculators.htm

http://www.wallaceracing.com/runnertorquecalc.php

http://racingfeed.com/downloads/chevy_flow_data.pdf

http://www.velocity-of-sound.com/veloci ... lator3.htm

http://2.3liter.com/Calc2.htm#MinCross

viewtopic.php?f=44&t=366&p=448#p448

http://www.highperformancepontiac.com/t ... index.html

http://www.highperformancepontiac.com/t ... index.html

viewtopic.php?f=55&t=1231&p=19119&hilit=runner+flow+numbers#p19119

DON,T FORGET TO MATCH THE HEADER SCAVENGING RPM BAND TO MATCH THE INTAKE AND CAM TIMING AND ENGINE DISPLACEMENT
in a properly designed combo cam timing,and duration, intake port cross sectional area and header length and diameter will be matched to displacement, compression ratio and drive train gearing so every factor is designed to peak efficiency at near the upper 2/3rds of the intended operational rpm band, and keep the critical piston speed below the peak operational rpm range

WHAT GOES IN NEEDS TO GET DRAWN OUT
viewtopic.php?f=56&t=185

portflow1.jpg

portflow2.jpg

portflow3.jpg

portflow4.jpg

and you want 425hp and as much torque as you can get

the stock intake and heads flow in the area of 200 cfm MAXIMUM, no big deal because the stock L98 head only flows about 200cfm,remember the TPI intake was designed to maximize torque on a 305 displacement engine so the runners were sized to match a 305 displacement and never increased when it was used on a 350, and its restricting a 350 displacement engine at anything over about 4000rpm

read this
/viewtopic.php?f=50&t=558

swap to an aftermarket TPI design , intake and heads with much larger port cross sectional area, that flows far better , and you can get far better results, IN BASICALLY a slightly higher but similar rpm band
stock.
the aftermarket intake designs can easily support over 250-270cfm plus,depending on design and port work. thats a huge jump in flow rates


350 ft lbs x 3500rpm =233 hp

let the heads and intake flow better, increase the compression ratio and displacement and bump up the rpm band with a slightly more agressive cam and raise the exhaust scavaging so you get 450ft lbs at 5000rpm =428hp

NOT DIFFICULT with a properly built higher compresion ratio 383

without loosing all of the BASIC tpi torque curve and instant off idle responce.

now Im not saying a mini-ram or stealth ram won,t make better peak hp, but I am saying youll need too swap too stiffer rear gears and get a higher stall converter speed to make full use of the much higher effective rpm range of those intake designs, while the basic TPI runs in the 1500rpm-5500rpm band the mini-ram and stealth ram produce lower torque in most cases up to about 3500rpm-4000rpm and only start to show huge gains AFTER the tpi becomes a restriction, increase the port cross section and flow rates and the basic TPI design is still a good functional intake.





http://www.rbracing-rsr.com/runnertorquecalc.html

http://www.compcams.com/Community/Articles/Details.asp?ID=1737510521

http://users.erols.com/srweiss/tablehdc.htm

http://www.malcams.com/legacy/misc/headflow.htm

http://victorylibrary.com/mopar/intake-tech-c.htm

here’s a chart FROM THE BOOK,HOW TO BUILD BIG-INCH CHEVY SMALL BLOCKS with some common cross sectional port sizes
(measured at the smallest part of the ports)
...........................sq inches........port cc
edelbrock performer rpm ....1.43.............170
vortec......................1.66.............170
tfs195......................1.93.............195
afr 180.....................1.93.............180
afr 195.....................1.98.............195
afr 210.....................2.05.............210
dart pro 200................2.06.............200
dart pro 215................2.14.............215
brodix track 1 .............2.30.............221
dart pro 1 230..............2.40.............230
edelbrock 23 high port .....2.53.............238
edelbrock 18 deg............2.71.............266
tfs 18 deg..................2.80.............250


DYNO DON POSTED THIS BIT OF INFO

"AFR 195 Eliminators
actual cc's in the intake port.....184
cross section area...2.13 sq.in
Flow spec's.....281/221

AFR 195 comp Eliminators
actual cc's ....189
cross section...2.15 sq.in
Flow spec's...306/235

Trick Flow 195 K D
before porting actual cc's....185
after porting ...188
cross section....2.13 sq.in
Flow spec's....270/210

Edelbrock Etec 200's
actual cc's before porting N/A
after porting....197
cross section...2.13
Flow spec's...270/218


Potential HP based on Airflow (Hot Rod, Jun '99, p74):
Airflow at 28" of water x 0.257 x number of cylinders = potential HP
or required airflow based on HP:
HP / 0.257 / cylinders = required airflow

ITS A COMON MISCONCEPTION,THAT YOU MEASURE PORT CROSS SECTION AT THE PORT ENTERANCE,BUT ITS NOT the port area at the enterance , you need to use in the calcs, ITS the MINIMAL port cross section at the SMALLEST point in the port, usually near the pushrod area.
LIKE a funnel, its not the largest part of the opening but the smallest thats the restriction to flow

SO HOW do you MEASURE THEN??

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=5649
05649.gif


http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM-900014&N=700+115&autoview=sku

sum-900014_cp.jpg



runner LENGTH and CROSS SECTION plus PLENUM VOLUME (if there is a plenum)effects the intake harmonics and how effectively you can ram tune the intake runner charge to fill the cylinders, and don,t forget exhaust scavaging , compression ratio and cam timing, and valve curtain area,and drive train gearing must match the intended combos effective operational power band

http://victorylibrary.com/mopar/intake-tech.htm

http://www.rbracing-rsr.com/runnertorquecalc.html

http://www.bgsoflex.com/intakeln.html

http://www.engr.colostate.edu/~allan/fluids/page7/PipeLength/pipe.html
 
http://www.bfranker.badz28.com/96ss/58porting.htm

http://www.geocities.com/Heartland/Fiel ... prtng.html


http://www.circletrack.com/techarticles ... ching.html

http://www.hotrod.com/techarticles/engi ... index.html

http://www.firstfuelinjection.com/products.htm

useful info here

valve clearance notches in pistons generally run in the area of 5cc-7cc


below Ive posted some linked info to play with
http://www.wallaceracing.com/dynamic-cr.php

https://www.uempistons.com/index.ph...e=comp&zenid=1e826335bfac0f356463eabed4958558

https://www.uempistons.com/index.ph...=comp2&zenid=1e826335bfac0f356463eabed4958558

http://garage.grumpysperformance.com/index.php?threads/crowers-valve-timing-charts.4299/

http://garage.grumpysperformance.co...-on-building-a-383-sbc-stroker.428/#post-4987

http://garage.grumpysperformance.com/index.php?threads/redline.343/#post-1170

http://garage.grumpysperformance.com/index.php?threads/what-con-rods-would-you-buy.942/#post-1658

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/

http://garage.grumpysperformance.co...ould-you-build-a-350-or-a-383-sbc-combo.8310/

http://garage.grumpysperformance.com/index.php?threads/semi-fool-proof-cam-sellection.82/

http://garage.grumpysperformance.com/index.php?threads/port-speeds-and-area.333/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.co...lsa-effects-your-compression-torque-dcr.1070/

350comps.png

he following are different static compression ratios (SCR) with a 3.48" stroke and different camshaft intake closing points @ 0.050" tappet lift on Keith Black's dynamic compression ratio calculator. The calculator, starting at 8.25:1 SCR. The dynamic compression ratio (DCR) has been kept at just over 8.0:1, a figure that is acceptable for use with today's pump gas with a little cushion:

  • Static CR....Intake closing point @ 0.050"....Dynamic CR.
  • 8.25........10* ABDC......8.010........................................................................................................
  • 8.50........20............8.012........................................................................................................
  • 8.75........27............8.022........................................................................................................
  • 9.00........33............8.018........................................................................................................
  • 9.25........37............8.061........................................................................................................
  • 9.50........42............8.029........................................................................................................
  • 9.75........46............8.016........................................................................................................
  • 10.00.......49............8.038........................................................................................................
  • 10.25.......52............8.043........................................................................................................
  • 10.50.......55............8.029........................................................................................................
  • 10.75.......57............8.069........................................................................................................
  • 11.00.......60............8.022........................................................................................................
  • 11.25.......62............8.038........................................................................................................
  • 11.50.......64............8.042........................................................................................................
  • 11.75.......66............8.035........................................................................................................
  • 12.00.......68............8.017........................................................................................................
 
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Re: porting the aftermarket TPI (Z51l9889 posted much of thi

Z51L9889;1290402 said:
Grumpyvette:

You are absolutely correct in everything you said, except for the 1205 gasket size. I checked the literature, plus measured my gaskets, and they come in at 2.09x1.28 = 2.68 sq. in. I was aiming for 1.875" at the runner choke point, which is 2.76 sq. in. There is some benefit to having the runner be slightly larger because of the flow losses associated with having the air stream make a 180 degree turn. .....
.


youve got me wondering if they changed the gasket port size over the last 10 years or so or perhaps the gaskets I have in the shop are some odd ball gasket set, or more likely placed in the wrong package.....they meassure like the 1204 gasket

http://store.summitracing.com/partdetail.asp?part=FPP-1206&autoview=sku
2.21 x 1.31=1206

http://store.summitracing.com/partdetail.asp?part=FPP-1204&autoview=sku
1.99 x 1.23=1204

http://store.summitracing.com/partdetail.asp?part=FPP-1205&autoview=sku
2.09 x 1.28=1205

just a bit of info on intake gaskets sizes to match port cross sectional areas

portcsa.jpg


COMMON SBC INTAKE PORTS
felpro # 1204=Port Size: 1.23" x 1.99"=2.448 sq inches

felpro # 1205=Port Size: 1.28" x 2.09"=2.67 sq inches

felpro # 1206=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1207=Port Size: 1.38" x 2.28"=3.146 sq inches

felpro # 1209=Port Size: 1.38" x 2.38"=3.28 sq inches

felpro # 1255 VORTEC=Port Size: 1.08" x 2.16"-2.33 sq inches

felpro # 1263=Port Size: 1.31" x 2.02"=2.65 sq inches

felpro # 1266=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1284 LT1=Port Size: 1.25 x 2.04''=2.55 sq inches

felpro # 1289 FASTBURN=Port Size: 1.30" x 2.31" 3.00 sq inches



but your correct, on the port size, looking at the info on the summit site. so just for the record I posted that info above
 
Re: porting the aftermarket TPI (Z51l9889 posted much of thi

I sort of have to agree with Grumpy. From what I have read, you are best just matching the intake and the head (gasket match) to remove the step transition. I removed some of the big casting bumps, but pretty much left most of the runners alone.

Here is my practice intake
before:
gm_0001.jpg


after:
gm_0002.jpg




And my new highrise

gm_0003.jpg

gm_0004.jpg



I installed the high rise yesterday. I looked down the runners with a flashlight, and can see a bead of RTV at the joint. Now I have to figure out how to trim it.
 
Re: porting the aftermarket TPI (Z51l9889 posted much of thi

Grump i've been looking all over and cant seem to find good flow info for the f.i.r.s.t. intake mani, i would love to incorporate one on my next tpi build, but want to be sure what im geting into so i can make educated choices about heads and cam and exhaust! any info on this?
 
Re: porting the aftermarket TPI (Z51l9889 posted much of thi

the FIRST intake lists its runner cross section diameter at 1.75" or approximately 2.4 sq inches in un-ported form, obviously that can be significantly improved with custom port work, and they state the intake supports 650hp BTW simple math shows you would need to have an engine make something like 570ft lbs at 6000rpm to make 650 hp so Id suspect they used a 427-343 SBC with that intake and about 12:1 compression, race octane fuel, with heads that flowed near 300cfm,
so its obviously far better flowing that the stock TPI intake with its smaller 1.47" diameter runners,thus its at least a 40% increase in cross sectional area, porting the intake should easily allow you to reach a 2.6 square inch cross section which in theory is a significant increase over anything a stock TPI is capable of reaching even extensively reworked versions.
The stock TPI even ported versions pretty much run out of air flow at about 4000rpm on a 383 Id expect at least a 1200rpm increase in potential power curve with the larger intake and use of a cam designed to be used in the 4000rpm-6500rpm power band in a 383 sbc with about 10.5:1 compression using good heads, a 3.73;1 rear gear, and a manual trans or 3500 rpm stall converter, and ID suspect good 1.6:1 roller rockers ,seems like it should work.
the very minor issue here is simply that you won,t have a valid before & after dyno result to compare between the two, intake manifold prep levels,if you install a modified and cleaned-up improved intake manifold without first using a stock as cast version,
thus you won,t have the ability to truly feel , or see on a dyno the DIFFERENCE,
your effort to increased efficiency had, on those improvements to the air flow rates, or the real measurable effect that had , had on the engine.
but I can assure you there is a measurable improvement , simply from similar pass intake port work.
Ive regularly seen power increases in the 15-20 hp range with similar work you've displayed,
but I know that gains in power from similar port & runner clean-up work, of over 25-30 hp are rather common.

something like these parts on a 383 sbc seems to be waranted
crane119651.jpg

http://www.airflowresearch.com/index.php?cPath=24_33

COMMON SBC INTAKE PORTS
felpro # 1204=Port Size: 1.23" x 1.99"=2.448 sq inches

felpro # 1205=Port Size: 1.28" x 2.09"=2.67 sq inches

felpro # 1206=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1207=Port Size: 1.38" x 2.28"=3.146 sq inches

felpro # 1209=Port Size: 1.38" x 2.38"=3.28 sq inches

felpro # 1255 VORTEC=Port Size: 1.08" x 2.16"-2.33 sq inches

felpro # 1263=Port Size: 1.31" x 2.02"=2.65 sq inches

felpro # 1266=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1284 LT1=Port Size: 1.25 x 2.04''=2.55 sq inches

felpro # 1289 FASTBURN=Port Size: 1.30" x 2.31" 3.00 sq inches

stealthram base
stealthbased.jpg

USE THE CALCULATORS, YOULL, QUICKLY FIND THE LIMITATIONS
http://www.rbracing-rsr.com/runnertorquecalc.html
http://www.wallaceracing.com/chokepoint.php
http://www.wallaceracing.com/header_length.php
http://arrc.ebscohost.com/ebsco_static/ ... SYSTEM.htm


PART NUMBER OPTION
Intake Manifolds For Vortec Heads

2116 Edelbrock Performer
21161 Edelbrock Performer, Polished 2116
5426 Edelbrock C-26 Dual-Quad
7116 Edelbrock Performer RPM
71161 Edelbrock Performer RPM, Polished 71161
2913 Edelbrock Super Victor, Single-Plane
2912 Edelbrock Victor JR. Sportsman 2V Vortec
7516 Edelbrock Performer RPM Air-Gap Vortec
75161 Edelbrock Performer RPM Air-Gap Vortec, Polished 7516
12496820 With EGR, square and spread bore carb mount
12366573 GM RPM Style, Squarebore Carb.
12496821 GM TBI with EGR
12496822 GM Eliminator Vortec Design (Same as Edelbrock P/N 2913)
------ Holley MPI Commander 950, MPFI Fuel Injection Kits.
3507 Edelbrock Performer RPM Pro-Flo EFI .
2516 Edelbrock Performer RPM (Marine application, but allows to bolt on a Quadrajet without an adapter) .

Note: You can view Edelbrock/Vortec intakes here

PART NUMBER OPTION
Intake Gaskets For Vortec Heads

1255 Fel-Pro Intake Gasket
89017465 GM Intake Gasket(old P/N 12529094)
Rocker Arms for Vortec Heads
12495490 GM Rocker Arms, 1.5 Ratio, Stamped Steel, Self-Aligning
12370838 GM Aluminum Roller Rocker, 1.5 Ratio, Self-Aligning
12370839 GM Aluminum Roller Rocker, 1.6 Ratio, Self-Aligning
1417-16 Comp Cams Magnum Roller Rocker, 1.52, Roller Tip, Self-Aligning
1418-16 Comp Cams Magnum Roller Rocker, 1.6, Roller Tip, Self-Aligning
1317-16 Comp Cams Pro Magnum Roller Rocker, 1.52 Ratio, Self-Aligning
1318-16 Comp Cams Pro Magnum Roller Rocker, 1.6 Ratio, Self-Aligning
10751-16 Crane Gold Roller Rocker, 1.5 Ratio, Self-Aligning
10758-16 Crane Gold Roller Rocker, 1.6 Ratio, Self-Aligning
Camshafts For Vortec Heads
There are hundreds of cams suitable for use with the Vortec head.
Example: 12-235-2 Comp Cam Extreme 4 X 4, flat tappet cam, lift I .447”, E .462”, duration @ .050” 210 degrees Int., 218 degrees Exh.

Strong low end and mid range torque. Excellent cam for RV's and pickups when changing to the Vortec heads.

Note: Valve spring change is required if changing to a performance cam.
PART NUMBER OPTION
Valve Springs For Vortec Heads

10309-1 Crane Cams valve spring and retainer kit. Drop-in springs with no machine work needed.
Valve Covers For Vortec Heads
12355350 GM Chrome With Red Bow Tie In Center
24502540 Valve Cover Adapter, converts center bolt to parameter bolt
10046089 Center Bolt Valve Cover Gaskets
241-75
Holley custom cast aluminum valve covers with ball-milled top. The rigid 1-piece aluminum castings combine strength and light weight in a design that provides a tight gasket seal while also acting to reduce valve train noise.

241-74
Holley custom cast aluminum valve covers with polished flat top. The rigid 1-pc aluminum castings combine strength and light weight in a design that provides a tight gasket seal while also acting to reduce valve train noise.

9415
Mr Gasket, 1987-up SBC, center hold down, baffled. Included: 2 covers, 1 oil fill cap, 2 PCV/breather grommets.

Head Gaskets For Vortec Heads
10105117 GM Composition Head Gasket, 0.028” thick compressed.
12557236 GM Composition Head Gasket, 0.051” thick compressed.
1094 Fel-Pro Head Gasket, 0.015” thick compressed.
PART NUMBER OPTION
Spark Plugs For Vortec Heads

5613611 R44LTS, set of 8
5614210 MR43LTS, set of 8
25164641 #3, Rapidfire style, set of 8
P526S Accel U-Groove “shorty” Double Platinum Header Plugs approximately 3/16" shorter then R44LTS plugs, set of 8
Miscellaneous Parts For Vortec Heads
12495499 GM Head Bolt Kit
12495491 GM Flat Tappet HD Push Rod Kit
12371041 Factory Roller Cam Push Rod Kit
12550027 GM Intake Bolts Set
134-2002 ARP SBC Vortec, Intake Bolt kit. 6-Point Bolts and Washers, Black Oxide, quantity of 8.
434-2002 ARP SBC Vortec, Intake Bolt kit. 6-Point Bolts and Washers, Stainless Steel, quantity of 8.
134-2103 ARP SBC Vortec, Intake Bolt kit. 12-Point Bolts and Washers, Black Oxide, quantity of 8.
434-2102 ARP SBC Vortec, Intake Bolt kit. 12-Point Bolts and Washers, Stainless Steel, quantity of 8.
8032 Edelbrock Universal Throttle Bracket. For SBC Vortec or Edelbrock E-Tec heads.
Bare Vortec Head
12529093 Same as P/N 12558060 except it doesn’t include intake valves, springs, and retainers.
 
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Re: porting the aftermarket TPI (Z51l9889 posted much of this)

Thanks for that info Paul, seems like naturally aspirated the 350 is not gonna get me to the power levels I want to be at, I would love to retain the TPI style intake to keep a similar torque curve and work down low so as to not have such a high revving combination, however if I want to be naturally aspirated its gonna require some stroking.
 
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