Pontiac 400 hp ?

[Mr Monte]

Any guess's on how much HP my Pontiac 400 will make ?

Ram air III heads (big valves)
9.7 to 1 compression
Comp cams 282 solid lfter cam
Comp cams roller tip rockers
Edelbrock Torker intake
1 3/4 headers
Holley 750DP
Accel coil

Most people are thinking around 300-330hp

[79 Z28]

are the heads stock? as in no porting or valve jobs etc. then id say ya to 300-330 :)

[formula mark]

When your talkin Pontiacs, you dont concern yourself with HP(that's for us chevy guys) It's all about the torque! 8)

[79 Z28]

When your talkin Pontiacs, you dont concern yourself with HP(that's for us chevy guys) It's all about the torque! 8)
thats funny, my chevy puts out tons of that too :P ;D

[formula mark]

When your talkin Pontiacs, you dont concern yourself with HP(that's for us chevy guys) It's all about the torque! 8)
thats funny, my chevy puts out tons of that too :P ;D

Obviously.
But ponchos are renowned for there low end tourque, not hp.

[Mr Monte]

are the heads stock? as in no porting or valve jobs etc. then id say ya to 300-330 :)


The heads are 1969 428 heads (#62) They came stock with 2.11 intake 1.77 exhaust valves. I had the heads rebuilt and had minor porting.

Flow at .500 lift at 28" Intake 233 cfm
Exhaust 193 exhaust

[mousemaker]

Should be at least 380, I think it'd be over 400. And torque should be 425-475 range.

[79TAFB]

the hp on that should easily be over 400 same with the torque....those poncho motors came stck with 320 ft/lb torque.

[79 Z28]

dyno that bitch and lets find out ;D

[79TAFB]

dyno that bitch and lets find out ;D

aayyyyyyyyy mateeeeeeeee

[Hume]

should be over 400 horsepower and a load more of torque. i am running a pontiac 400 that has decently close specs to yours and I am rebuilding another 400 for a '67 GTO both engine will make over 400 horse quite easily...good choice in chosing poncho power!

[IROC-Z]

When your talkin Pontiacs, you dont concern yourself with HP(that's for us chevy guys) It's all about the torque! 8)
thats funny, my chevy puts out tons of that too :P ;D


too bad it can't hold itself together :P

[79 Z28]

id like to se a poncho last at those rpms :P mine played up there from time to time for almost 4 years, then one day it spent about 30 sec playing up there, and it tapped out. oh well what do you expect from dead stock 5.7 rods :P ;D

[Hume]

read brothers!
www.pontiacpower.com

[79 Z28]

for the record i was talking stocker bottom end ones not fully modified race motors :)

[Hume]

pontiac cranks can hold up to anything you can throw at them, the only weak point is the connecting rods...which are stupid expensive

[79 Z28]

pontiac cranks can hold up to anything you can throw at them, the only weak point is the connecting rods...which are stupid expensive
well same goes for the 350. when my motor went it was a connecting rod, crank didnt break, even after the explosion that disentegrated the entire inside its still in one piece.cranks are the strong point in any rotating assembly anyways and are usually the last thing to break unless a cap breaks or in high rpm cases the journal oblongs and the crank waivers causing it to stress fracture.

[Hume]

i do agree with you that pontiac's wunt last at high rpm's...but that doesn't matter because they were built to make all there power at streetable rpm's. i wouldn't rev it past 6 grand unless its a race engine

[79 Z28]

i do agree with you that pontiac's wunt last at high rpm's...but that doesn't matter because they were built to make all there power at streetable rpm's. i wouldn't rev it past 6 grand unless its a race engine
well i never said it wouldnt last at high rpms, everything can be modded somewhat, but the powerband is dependent on the cubes of the motor, then the components used. my old 355 made over 390 lbft from 3100 to 4400 and peaked at just over 400. thats a broad torque curve thats low and mid, right where you want for the street. and that was a stocker combo. in the world of power 350 is adequate to get you the race power and a balance of street power. thats why chevy rules so much, not to mention the chevy sb and bb make sick power and are some of the cheapest motors to build up in the aftermarket world and are really strong combos. ill never run anything else in a GM vehicle, unless i buy a ford then ill run ford and dodge to dodge etc. ;D

dont worry im a racing fanatic and a chevy guy, so i hold to my preferences :)

[Mr Monte]

I kind of find it funny that people tell me that these motors are expensive to build. Me and my friend (who built a 454) went out and bought alot of the same parts. My pistons were cheaper and if we wanted Edelbrock heads mine are cheaper too. The rest of the parts besides bearings are within $20. I know a small block is very cheap to build but I have never had good luck with them.....damn rods. Besides it's kinda neat to have somthing different under the hood.

[89vert]

Buick 455 all the way
Big bore, short stroke oh ya ;)

[mousemaker]

If you like big bore small stroke, Olds 403 way beats Buick 455.
(4.351x3.385 compared to 4.313x3.900)

[89vert]

If you like big bore small stroke, Olds 403 way beats Buick 455.
(4.351x3.385 compared to 4.313x3.900)

I got a 71 442 with a 455olds torque monster but weak in the top end


when shes done me and 79z28 can have a n/a race 8)

[Mr Monte]

Buick 455 all the way
Big bore, short stroke oh ya ;)


Beem there done that. This is the most expensive motor to build next to a Hemi. Want to see some prices go look at TAperformance

[79 Z28]

If you like big bore small stroke, Olds 403 way beats Buick 455.
(4.351x3.385 compared to 4.313x3.900)

I got a 71 442 with a 455olds torque monster but weak in the top end


when shes done me and 79z28 can have a n/a race 8)
no problem 8)