upgrading your 454 BBC to a 496

[grumpyvette]

HEY GRUMPYVETTE?
I am about to pull the engine out of my car for a freshen up, rings bearings etc and have been thinking about ways that I can make the engine Bullet proof.

I drive it hard, run a manual and like to go fast but always have the thought in the back of my mind that the engine is going to go BANG so would like to buy myself some piece of mind.

Had the engine freshened and dynoed a year or so ago by a professional builder but have not been really happy with it since. Made lots of power, 480hp 540lbft, but started breathing quite heavily not long after the rebuild so am going to go through it again, rings bearings gaskets etc.

Is is only a 2 bolt block so I am never going to be able to go mad but the more I think about it the more i feel that a set of Eagle rods and a balance would be of benefit.

So, my question is, does anyone have any opinions on this and are the Eagle rods any good.

https://www.mfrexpress.com/alloy-swivel ... p-701.html
lets put it this way I give away for free or UNLESS its a stock rebuild for a car or truck used as daily transportation, I usually throw ALL 3/8" rod bolt chevy OEM connecting rods in the dumpster, and use SCAT,EAGLE,OLIVER or CARRILLO, MANELY , OR CROWER connecting rods with 7/16" rod bolts as a standard procedure on rebuilds.
it costs more to correctly rebuild chevy rods and add 7/16" arp bolts than some of the decent but low cost aftermarket connecting rods cost.


http://www.adperformance.com/index.php? ... =67_87_131

viewtopic.php?f=53&t=510

http://store.summitracing.com/partdetai ... toview=sku


adding an ecomomically affordable 1/4" stroker kit to a 454 thats not going to be abused a great deal, as its mostly a street/strip deal is a NO BRAINER its FREE HP/TQ and I can,t see why almost every rebuild doesn,t do this as an option,
but because your running pump gas and adding displacemeny ID suggest boosting the cpr to about 9.6:1 and adding ARP main studs durring the rebuild and keeping the RPMs to UNDER 6000rpm with the stroker crank, in that two bolt block.

http://www.adperformance.com/index.php? ... =67_87_131

http://store.survivalmotorsports.com/scat.html

btw a cam like this in a 10:1 cpr 496 with the correct matched drive train gearing and trans would be impressive on the street

http://store.survivalmotorsports.com/ca ... haust.html



$200 more gets you a forged component deal


Eagle 4.25 "496" Competition Stroker Kit, 10:1, Forged, 2rms
$1,699.00
Eagle 4340 Forged Competition Rotating Assembly

Eagle 4340 Forged 4.250 Stroke Crankshaft
Eagle 4340 Forged 3D H-beam Rods (W/ ARP 8740 Bolts)
JE SRP 18cc Dome Piston (~10.2:1 w/ 118cc heads, others available)
Perfect Circle or Mahle Plasma Premium Performance Rings
Clevite or King Competition Series Rod and Main Bearings
We can fully customize these kits to your needs. If you don't see it listed please inquire.

Competition 454 Rotating Assemblies

2pc Rear Main Seal

All Eagle Competition assemblies include our forged 4340 chromoly crankshaft, our forged 4340 chromoly H-beam rods, forged SRP pistons, Clevite77 race bearings, and Perfect Circle Rings. All are designed for internal balance.

Recommended for use up to 850 HP (1500 HP with optional ARP L-19 bolts)





Grumpy

What are your opinions on the Com Cams 292H cam with the 496?

Car is a 56 Chevy with a DNE 5 Speed and a 9"ford with a 3.0 ratio and 29" tyres.

Not sure on the weight but I would guestimate around 3500lb?



now its obvious that each person defines (STREETABLE) in a differant way and some guys don,t mind having to drop down a gear and reve the engine to get moving or have stuff on the dash bounce around at idle, I define (STREETABLE) as having a combo you can jump into and drive on a 1500-2000 mile trip without worrying about problems, or sitting in 2 mph traffic for an hour without having to shut the darn thing off.

heres how comp cams lists that cam

"HYDRAULIC-Street/strip applications. Hyd. Hyd. 2500 to 6500 11-213-3 292H 292 292 244 244 .550 .550 110°
10:1+ compression, 3000+ stall or 4 speed.
4.10 or lower gears & aftermarket intake.
Very rough idle."

that 3.0 rear gear will cause problems


heres the two next milder cams they list

HYDRAULIC-Great for street machines. Hyd. Hyd. 2000 to 6000 11-208-3 280H 280 280 230 230 .520 .520 110°
Use headers and 9:1+ compression. In
396-402 use 2500+ stall, lower
gears. Rough idle.

HYDRAULIC-Needs 9.5:1 compression, Hyd. Hyd. 2200 to 6200 11-318-4 286H 286 286 236 236 .556 .556 110°
2800+ stall, headers, and lower gears.
Choppy idle.

if your intention is good street manors ID sellect one of THOSE, MILDER CAMS, and keep the cpr in the 9:1-9.5:1 range
yes before you ask the H292 makes more hp and yes a 496 displacement tends to make the cam act milder........BUT your still probably going to want a 3.54-3.73 :1 rear gear ,to make the combo pleasant to drive,in traffic, your first gear ratio times the rear gear ratio should generally fall in the 10:1 range in a performance car, ESPECIALLY with a cam that won,t run really smooth below about 2000-2500rpm .

If your trying to get max hp on a strict budget,thats a totally differant goal, and a 496 BBC with 12.7:1 cpr and a cam like this

Chevrolet Performance Camshaft; Part Number SS4265


lifter-type
Solid

Big Block 1967-93 396-454; intake-duration@.050 lift 264; exhaust-duration@.050 lift 274; intake-lift .612; exhaust-lift .637; lobe sep angle 108

will get you that killer hp,compared to the milder engine combo, both on a low budget 496 build, but youll want 4.56:1 rear gears and heads like these

http://www.trickflow.com/partdetail.asp ... toview=sku

http://www.airflowresearch.com/17-23.pdf

and it won,t be a decent daily transportation, and it probably won,t run well on pump gas.

adding the extra displacement and higher compression with a stroker kit will boost torque noticeably from the current 454 combo, if you keep the same type cam its going to run noticeable better with the changes, but you need to define your goals, if its a great combo for cruising and massive torque thats way different than going for impressive peak hp numbers, you'll still destroy tires at will with either combo, but the milder one will do it almost instantly when the throttles depressed while the other combo will make the car faster, but less fun to drive in traffic.having a REV-KIT that retains the lifters in their bores, to maintain oil pressure, even if the rocker comes loose or push rods breaks is a good idea

 

[grumpyvette]

if i run a rev kit (springs that push down on the lifters) should i run softer valve springs then the manufacturers recommendation? anyone have an insights on that?

no! you run the same springs, the normal valve spring pushes down on the push rod thru the rocker, the reve kit only adds pressure to the outer lifter body to maintain roller lifter contact with the cam lobe, lighter weight valve springs will allow the lifter seat to pump up faster

viewtopic.php?f=69&t=189

viewtopic.php?f=69&t=916

viewtopic.php?f=69&t=591


this info might help


now admittedly IM writing this some what tongue in cheek, because Im well aware of the addicted, at times even RABBID SBC faction,
BUT as a dedicated BBC, and old school Pontiac, and mopar BIG BLOCK FAN, who likes building 454-540 bbc, 455-468 Pontiac, 440-500 MOPARS and 392 hemi,s, IM always amazed at the guys who want to stick with the sbc rather than upgrade,to a basic block config thats designed for the extra displacement. but I get guys in my shop all the time who want to build 427-454 SBC engines, for street strip use, and expect both decent street manors and 550-600 flywheel hp I build occasional sbc engines of 406 (.030 over bore 400sbc engines)and 426 (4.185 bore/3.875 stroke sbc engines)displacement, but far more 383-396 simply due to the base 350 block being far more common, I build a good deal of 383s designed for nitrous us, that easily exceed 550-600hp on the giggle gas, but once you get over a 3.875" stroke things are getting pretty tight in the cam/connecting rod clearance so I try to steer them into a BBC combo if I can, for the simple reason that its a lot simpler to build a 482-489-496 BBC (4.25" stroke 454 with or without a slight over bore) and in most cases the final product cost per horsepower will be slightly in the bbc favor once you try to exceed 550-600hp N/A
yes I can hear the screams already!
but after you have a few brandys and think it thru, many guys find Im correct,If your goal is 550-600hp plus N/A, and you want both reasonable drive ability on the street and an occasional bonzi charge to impress your buddies with reasonable chances of taking the car out without maintenance issues, a big block makes more sense to me

OK ILL STEP BACK, YOU CAN START SCREAMING AND BURNING MY LIKENESS IN EFFIGY


your engines torque curve is more the result of displacement, compression,ratio,selected cam timing and both header design (scavenging) and intake design (SINGLE vs DUAL PLANE ETC.)than just port cross sectional area alone, and if your wearing valve guides the valve train geometry and clearances, and lubrication system, and the oil used in it, and your valve spring rates and seals need to be carefully checked and a rocker stud girdle and roller rockers used
and port cross sectional area and flow numbers have a larger effect than port shape alone
naturally you'll need to match the port cross sectional area, length, and plenum to the intended displacement and rpm band, and cam timing, but just assuming a swap from rectangular port to oval will always result in more torque will not always be true over the whole power band, especially if the rest of the combos designed for a totally different rpm band than the heads you've selected.
tweaks like tuned merge collectors, and slightly different cam timing and intake swaps can get a great deal more of the torque potential from a slightly different port size,and there are calculators you can use to find a limited selection of choices,in header length, diam., collector, intake port length and cross section and runner length, plenum size, cam timing and valve size to look thru.. too narrow your search for the best match to your application vs just guessing and swapping parts till you think you've got it correct

http://forum.grumpysperformance.com/viewtopic.php?f=52&t=333

many guys will tell you that selecting oval port heads is better on a street car engine, and they generally have a point, yet depending on compression ratio and cam used you may never notice any loss of low rpm torque, if you select a reasonable size rectangular port head and matched components ,this is one of the huge semi-myths about big block engines.
while its true that the low rpm torque does tend to be reduced with stock oval port heads vs stock rectangular port heads ,its also true that the compression, intake manifold, cam timing,rear gearing and header designs all change the results and its very easy to build a rectangular port engine that destroys tires, and theres a huge range in size of the ports in BOTH oval and rectangle port aftermarket heads

http://www.carcraft.com/techarticles/cc ... ewall.html

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Peaks and Averages
................Avg. TQ Avg. HP Peak TQ Peak HP
Iron .. ........541.1 475.0 595 .........521
Edelbrock 582.1 514.9 618 ........582
Dart .......... 584.2 517.7 615 .......595
TFS ................590.3 522.5 626 ... 595
Brodix .....590.8 ........523.0 626 ........597