TheViper

i was just thinking, how hard would it be to get 400rwhp out of a 454? could you use stock heads and a cam with about 230-240intake duration at .050 and about 9.5-10-1 compression?

ede

lot would depends on which set of stock heads you had, but it wouldn't be hard to do with right combiation of parts

chev496

raise that compression up a little bit. You will be losing all the air in the chambers if you run low compression and a big cam.

f-crazy

iTrader: (-1)

i wouldnt really call a 230 cam in a 454 a big cam...more like a RV cam, in which case youd make A LOT of torque....i agree on the C/R...10.5-11 would be about perfect, probley a 250-260 solid roller would be a decent daily driver,...So To Speak... and make a lot of HP to...i dont know to much about the stock 454 castings, but im sure there are some out there that with some really good porting would really be a big bang for the buck.

TheViper

thx, i've been thining about putting a big block in my 84 z28 but i think it would be more of a pain that its worth. what i think would be better is putting one in a '80 TA that already has a 455 pontiac in it. the pontiac has a ton of torque but good heads are so hard to find for it without spending a ton. do you think i should keep the 455 or go with a 454? how big of a cam do you think i could go with in the 455? it has a summit 2802 with 224 intake duration and with 2.41 rear gears, posi, and 225s it will spin them off idle like nothing. it also has a pretty smooth idle.

f-crazy

iTrader: (-1)

id stay with the 454...itll make more power and parts are 10 times easier to find...

that 224 in a 455 is like a peanut cam 350....


i wouldnt go smaller then a 250 solid roller....in a chevy 454

TheViper

how come all of the pontiac people tell me that the 224 duration cam is about as big as i should go even though it has a smooth idle and burns the tires off with 2.41 gears off idle? is there some reason pontiacs like small cams? i would think you could get away with a bigger one since it has a longer stroke(almost 1/4") and therefore more bottom end power to spare.

is it the heads that can't flow at high rpms? i have a spare set of 6X heads that i might try to hog out.

also, how high can you rev a 454? i understand that the 455s shouldn't be turned above 5000.

i wish i could find a 454 around here.

grumpyvette

you really should get these books and read them before going any further, it will help a good deal
getting 400 rear wheel hp is not a huge challange from a 454


http://www.amazon.com/exec/obidos/AS...234339-0571324


http://www.amazon.com/exec/obidos/tg...glance&s=books



http://www.amazon.com/exec/obidos/tg...glance&s=books


http://www.amazon.com/exec/obidos/tg...glance&s=books


http://www.amazon.com/exec/obidos/tg...glance&s=books

http://www.amazon.com/exec/obidos/tg...glance&s=books


heres more bbc info, but don,t let the guys make you think only oval port heads work well! it totally depends on your combo,s rpm range,displacement,gearing,weight,cam timeing,etc
http://www.idavette.net/hib/vette_bbfh.htm

http://www.protopline.com/racingaluminumbbc.asp


http://fteufert1.home.att.net/bbchevy/bbchevy.htm

http://roadsters.com/bbc/#prep

http://roadsters.com/bbc/#bore

http://roadsters.com/bbc/#oval

http://www.chevelles.com/racing/BBCombo.html

http://www.edelbrock.com/automotive/raceheadbbchev.html

http://www.dragraceresults.com/worldcastings/


http://www.nastyz28.com/bbcmenu.html

general big block info!

http://www.amotion.com/cbb.html

http://www.edelbrock.com/automotive/headbbchev.html

http://roadsters.com/bbc/

http://www.teufert.net/bbchevy/bbchevy.htm

http://www.chevelles.com/racing/BBCombo.html

http://www.racingengines.com/public/sales/wrldprd1.htm

http://www.holley.com/HiOctn/ProdLin...P/Chevy30.html

http://www.mortec.com/location.htm

http://home.hiwaay.net/~ppatter/patr...dd_article.htm

http://www.bigblockchevy.com/Bittner...lky1500Hp.html

http://www.edelbrock.com/automotive/7161pp.html

http://www.onlineperformanceparts.co...es/ablock1.htm

http://www.off-road.com/chevy/tech/454engine/

http://www.directhits.com/ChevyDynoReport.asp



http://www.theengineshop.com/techinfo7.shtml

http://www.dodgeram.org/tech/gas/specs/crank.html

http://www.diabolicalperformance.com/diabolical540.html

http://avs.epix.net/schorrperformanc...evyBB_290+.htm

http://avs.epix.net/schorrperformanc...hevyBB_290.htm

http://www.diabolicalperformance.com...evalue468.html

http://chevyhiperformance.com/techarticles/93650/



big blocks like more compression, bigger carbs and a slightly larger cam than small blocks if thats what your used to building btw

SSC

It really doesent take squat to get good HP from a 454, a RV cam will put one close to 400 at the crank depending on which you choose. I'm not fond of square port heads there too expensive! GM had a few good casting closed chamber heads that perform quite well with minor P&P work.

chev496

if you run a cam with 250 @ .050.. u better have yourself one hell of a stall converter. I have a 230 in mine with a 107 lsa and it kicks in the power band at 2500 rpm with a victor jr intake and 66 vette oval port heads, 11:1. And let me tell ya, that thing is on the verge of a strip car with that cam. I wish i woulda went 1/2 point lower on compression and around 10 degrees lower on the cam and it woulda made for a bad street car.

TheViper

thanks, i'l have to look into some of those books.

jpk91rs

To get 400 hp from a 454........ I would probably put a small roller cam in it and then crank it up and let it idle tha should just about get you there.:rockon:

BIRD91ZRAG

iTrader: (1)

The biggest problem with Pontiac motors is the CAST connecting rod. Thats right, people...no luxury of forged rods here. Except in the early 60's and 73-74 Super Duty motors. The redline on the 455 was 5200, and I've seen several 455's with rods snapped in half, and plenty of cast pistons yanked in half. Why have a cam that will make power from 3000-6500 and only be able to use 3000-5200?
A 454 will rev to 6500 all day long with the standard 3/8 bolt rods with good rod bolts. Don't need rectangular port heads. A good head is the 791 casting. If you want to make real HP put a pair of Dart Pro 1's on it and a decent XE cam. 500 FW HP is easy. LS6's had 450 HP at the FW with a small solid lift cam, 242@.050 with .496 net lift. Headers are a must. BBC exhaust manifolds choke almost 20% from the HP.
There's nothing quite like a 3900# Chevelle LS6 with a turbo 400 and 4.10 gears. With stock exhaust and Polyglas tires, It's not MPG, but TPM...tires per mile

Oh yeah, your 7 1/2 rear WILL NOT like the 454!!!(neither will the 700R4...)
And a stock LS6, with the GM cam listed above, will be happy with a 2000-2200 stall converter.