[409guy]

Hey guys i have a 1970 lemans with a 350 it has a 2bbl and single exhaust and i was wondering if you guys could help me, i need to know how much hp i have. If anyone could help me that would be awsome i saw some where that it was only 160 hp but i also heard that it was 255....what do you think?

[ February 22, 2003: Message edited by: 409guy ]</p>

[nickel333]

dude its not going to be the 255, you have a single exaust.

[409guy]

well check this site out, and remember i got a 1970 http://www.wallaceracing.com/engine.htm

-409guy

[Halloweenking]

409 guy if you can give me the block code I can tell you for sure. Its located on the passengers side in front. There will be a 2 caracter block code. PM me with the code and I'll get back to you as soon as possible.

HK

[ February 20, 2003: Message edited by: Halloweenking ]</p>

[bullheimer]

i'm with nickelback, if it's single exhaust it will be the grocery getter economy model even if it is a 70.

[drewhelm]

I've checked and the 70 350 is rated at 255. Both on Wallace Racing and Classical Pontiac. Keep in mind even the 4 barrel cars were single exhaust......

[409guy]

thanks a lot man, that is a relief. how much extra hp do you think i would get with a air gap intake and a 4bbl?

-409 gu....350 kid

[slider]

Steady Big Fella!!!

Don't forget that your 255 Horsepower existed solely in some advertising wonk's mind, and even then it had to be after the third martini at lunch.

A-a-a-a-a-a-n-n-n-n-d that pie in the sky number fell like a stone the next year with basically the same engine to the 160 range, which was REAL, not something adjusted to zero sea level at 98% humidity with minimal cloud cover at 72.234678987 degrees with no water pump, alternator, air cleaner or exhaust system, perfect timing (would NOT start or idle at this setting), 120 octane fuel and an engine temperature unsustainable on the street longer than three minutes without grenading the hell out of everything.

[Croz]

wait wait wait... does it have a 2 barrel or a 4 barrel on it now? Because your last post makes it sound like a 2 barrel, and you won't be getting much of anything out of that, unless there are 2 more :/

[dallam1]

Horsepower scmoorspower, who cars? Just do the typical hotrod hopups with that old 350 and God will bless you with being able to put black tire marks up and down your street! Heck, I don't have a clue how much horsepower is in my Olds Cutty with a 455 but my street looks like an airport runway because of all of the black marks. The best part is that I get to see all of my lovely neighbors in the morning dressed in their nightgowns and bunny slippers, throwing tomatos at me when I go to work.

[Croz]

you can't take the same approach as a SBC 350. They are not the same engine. Is it a 2 barrel or a 4 barrel carb? i would guess a 4 barrel, and regardless, why don't you just install a duel exaust? throw some headers on it and make it mean

[ February 22, 2003: Message edited by: Croz ]</p>

[dallam1]

Being that your 350 is a 1970, you probably have higher compression than the later model smog engines but if your engine is in fact a 2 barrel version, then the truth is that I don't know for sure. Do a compression check on one of the cylinders for us. If it's over 150 pounds then hot dog, you're in the hot rod game and that motor will wake up, for sure with the addition of dual exhaust and a mild cam. If your cylinder pressure is below 130 pounds then don't dispare, there are some things you can do to up the compression but it will start costing you money. Incidently, that engine is an "under square" design and thus has the same inharent problems that the Chevy 305 has because the cylinder bore is on the small side and won't let you run big valve heads without problems. If your motor is a low compression model and needs work, I would install duals and thats it until I located a 400 or 455 engine. All of the Pontiacs have the same block dimensions and will interchange (except for the 301). I've had three Pontiac engines, a 389 and a low compression 455 and a high compression 455 and they all had great street torque! Good luck

[409guy]

Right now it has a 2bbl but come this time next week it i will have a new 4bbl and semi hi-po intake.
-409 guy
O and by the way i know where a 455 is. It actually belongs to my older brother. the only problem is, it has been sitting under the weather for about 2-3 years. So if you guys think i should get that then i mite just have to.

[dallam1]

Well, go to your older brothere's house as fast as that old wore out 350 will get you there and ask him for a big fat cresent wrench and try and turn the crank on the 455. Mind you, you'll have to put both hands on that wrench and pull like the bejesus! Now, get off the computer and head over there pronto and report back to us!

[drewhelm]

There ar 2 reasons for the HP drop the following year....1) Net HP including all drive accessories including WP, alternator, power steering, and AC compressor. 2) Significantly lower compression. In addition, I believe they used a lesser cam the following year, too.

An airgap intake for a Pontiac? Actually, all Pontiac intakes have a gap between the bottom of the intake and the valley pan. For a 350 engine dual plane Edelbrock Performer intake is your best choice. Put a cam in it.....maybe the Summit 2801, a set of headers and dual exhaust and a Holley 650 vacuum secondary carb and you're in business.......should EASILY make right around 300bhp if they are the original 70 heads.