Looking for a pontiac 455

[capitlj]

adog wrote:
Pretty much that an LSX engine with wiring harness, PCM, and sufficient tweaking to produce 450-500 hp would cost more than a big block crate engine, at least if you got new parts. Also, the LS1 and LS2 were installed in the Formula/Trans Am and GTO, respectively, so putting them in a Pontiac would seem reasonable.

I dont think you could spend another 5 grand on bolt ons and only get 400-500 hp on an ls crate motor. The general rule of thumb for those of us in the know is that big block parts will be double the cost almost all the time.

[adog]

I had based my estimate on the following:
LS1 crate engine + H/C: approx $7,000 + electronics, low 400 hp range
502 cid crate engine: approx $5,800 + carburetor, ignition, 450 hp

If the existing 400 is in good shape or an economical 455 can be obtained, that would be the most affordable route.

[MisterCMK]

The 400 or the 455 is the only logical choice. For one its a pontiac motor. Second, its a pain in the ass to find mounts to fit a chebby in the pontiac.

[capitlj]

I was saying all along that the 455 is the better way to go just building one to make 500 hp is gonna cost roughly twice as much as putting in a 350 that makes the same power. Screw an LS motor why put all that electronic crap in a classic car like that?? Sure you can't get the same kind of turn key operation fuel injection gives you but the install is three times as complicated, plus you have sensors to maintain/replace and diagnosing a problem can be a PITA with fuel injection.

[MisterCMK]

capitlj wrote:
Sure you can't get the same kind of turn key operation fuel injection gives you

Not true. Have you ever owned a carbuerated vehicle?

[LightEmUp]

Man....... you guys are getting into stuff I didn't want to know, I will be putting a <u>pontiac</u> 400 or 455 whether I bore it out or not which I probably will. I have some hookups through my dad, he knows some people in the auto business, but anyways im not that worried about price all I asked does anyone have a 455 you guys took it out of the park around the block and then some, o well also does anyone have a winter beater car for me so i can actually rip the 400 out of the car so I can get it rebuilt if no has a 455 well you guys have fun with that LS shit

[capitlj]

No i havent thats just what i hear from people who do as far as cold starts go. The only reason i said anything at all on this thread was because someone said a big block would be cheaper than a small block thats just plain madness.

[94NDTA]

LightEmUp wrote:
Man....... you guys are getting into stuff I didn't want to know, I will be putting a <u>pontiac</u> 400 or 455 whether I bore it out or not which I probably will. I have some hookups through my dad, he knows some people in the auto business, but anyways im not that worried about price all I asked does anyone have a 455 you guys took it out of the park around the block and then some, o well also does anyone have a winter beater car for me so i can actually rip the 400 out of the car so I can get it rebuilt if no has a 455 well you guys have fun with that LS shit
Putting in a crate LS1 is going to be a hell of a lot easier to get running right than a carbed 400 or 455.

But I would rather get as 455 too. Don't even bother with a 400.

[LightEmUp]

Yeah I really want to go with the 455 but it is so hard to find a pontiac 455 that is an early 70's those are the ones with the most horsepower If I end up going with the 400 it wont be so bad because i will be able to put better parts on it with the money I will be saving from not buying the 455 and I think a 455 has more expensive parts, but most parts are able to go on either what ever I do it will be sweet and it will definately be mean as hell

[MisterCMK]

You can get a 455 block out of any pontiac. Throw an aftermarket set of heads on there, bore it and stroke it and you're easily over 500hp.

[94NDTA]

MisterCMK wrote:
You can get a 455 block out of any pontiac. Throw an aftermarket set of heads on there, bore it and stroke it and you're easily over 500hp.
QFT.

The only reason the older ones have more power is because of the exhaust, carb and cam. If you plan on swapping that out anyways, might as well pick up any 455 you can.

[capitlj]

MisterCMK wrote:
You can get a 455 block out of any pontiac. Throw an aftermarket set of heads on there, bore it and stroke it and you're easily over 500hp.
Not quite guy you gotta have a good carb to feed all those cubes and some headers to manage the flow. Plus a good set of aftermarket heads are well over $800 per side. If possible work the stock heads most BB heads can have bigger valves stuffed in then do the engine work should save you a solid $500 but it wont be cheap, and you'll have to do your homework. Best way to do that is to ask guys who have already done it.

[MisterCMK]

The stock q-jet is good up to 500 or so hp. The Ram Air IV manifolds are just as good as a set of headers. I forget which casting it is, but the stock Pontiac heads with a little porting and polishing are exactly what aftermarket heads are designed after.

Come back when you learn something about the pontiac motors.

[tqisking]

I really wish people would quit calling the pontiac engine a Big Block...it is not all pontiac engines 326-455 are all physically the same size, period....

This is simple

Take your 400 out ( or buy another block, I may have a couple) Bore it to 4.150 (.030 over)
Buy a eagle 3" main 4.250 stroke crank ($299) buy a set of 6.8" BBC rods and the correct piston for the stroke and rod for a deck height of 10.220". You can buy this rotating assembly balanced and ready to go (besides cleaning) for $2000.00

As far as heads are concerned go and find some 6X -4 castings the -8's are ok also but they are a lower compression, send them to a shop for a street strip port job, I suggest Butler performance in lenoma TN www.jbp-pontiac.com ....They will get you set up, just tell them what you are looking for, I always talk to David Butler, super nice guy and he is very helpfull.

Camshaft just go with a extreme energy from Comp Cams, you will have to know what size engine you are going with first and what the heads flow...

I would try and get a 850 cfm carb on it with a single plane manifold and some 1 7/8" headers if you go with the bigger engine

All in all plan on around $4000-$5000 for 500-550 hp and more tq than you can hook up, nice thing is that you will not have to spin the snot out of it so it will last a long time, but be prepared all that tq will find you weak spots

But what do I know? hehe

Chad

[tqisking]

ps do not bore it until you have the pistons so you can measure them for the correct fit...I could assemble one for you if you need it

[MisterCMK]

tqisking wrote:
I really wish people would quit calling the pontiac engine a Big Block...it is not all pontiac engines 326-455 are all physically the same size, period....

Yup, like I said.

MisterCMK wrote:
BTW, there is no "big block" or "small block" with the pontiac motors. They are all the same physical size.

[capitlj]

Big block or not there is no way a stock quadracrap could feed 500 horses it would at least have to be rebuilt for more cfm, and the stock manifolds might get you the numbers but numbers aren't good for anything but bragging. You want that motor to continue building power as the RPM's go up, with stock manifolds it will fall on its face at about 4000-5000 RPM ported or not. Maybe there are some good factory cast iron headers like you get on 89-up 5.0 stangs those might work.

[MisterCMK]

d00d, you obviously know nothing aobut the pontiac motors. Give it up.

The motors don't have to spin high to make all their power. They make the power down low.

Seriously though, give it up.

[Guest]

capitlj wrote:
Big block or not there is no way a stock quadracrap could feed 500 horses it would at least have to be rebuilt for more cfm, and the stock manifolds might get you the numbers but numbers aren't good for anything but bragging. You want that motor to continue building power as the RPM's go up, with stock manifolds it will fall on its face at about 4000-5000 RPM ported or not. Maybe there are some good factory cast iron headers like you get on 89-up 5.0 stangs those might work.

I'm thinking Chad (tqisking) knows a bit about this subject, you might wanna leave the technical aspect of things to him.

Having said that, I still vote for a 2JZ swap.

[tqisking]

Here is a 600hp pump gas Poncho if you are interested

http://forums.performanceyears.com/forums/showthread.php?t=492069

Chad