Jump to content

Pontiac Power who's got experience


99StockGT

Recommended Posts

So I'm once again fighting with myself and I think it's finally time to bite the bullet and do a little modification. Ran into a cooling issue the past couple weeks and upon working on the ORIGIONAL waterpump realized we are going to need some TLC on the LeMans motor. 98% of the engine is origional and I would like to keep it that way however there's much more fun to be had from her with some goodies under the hood.

 

SO,

Question 1 : Who local has experience rebuilding/restoring big block pontiacs and won't rape me on costs?

Question 2 : Rebuild and upgrade or rebuild to origional spec and purchase a crate engine for running around having fun without destroying value of the car?

Question 3 : To hell with it and go big or go home. Bored / Stroked / all the fixins and turn it into a street monster :fuckyeah:

Link to comment
Share on other sites

i guess you have to ask yourself this question....

 

do you have other toys..

 

do you show this car?

 

do you ever plan on re selling this car?

 

you see where im going. if you have other toys, and if you show it, or plan on reselling it, i say just go with a good rebuild.

 

if you dont have other toys, dont plan on reselling it then go all out.

 

i personally do not know of anyone near you that does good work. down in my neck of the woods yes.

Link to comment
Share on other sites

Austin I've seen your lemans and it's very nice. So often people cut up "base models" and go crazy on them. It's good to see an example of any every day car from back then especially with how clean and original it is. It may not be as fast as same year GTO but you will probably have the nicest lemans at any show you go to. My two cents is rebuild and make it LOOK as stock as possible. Adding an original pontiac 4brl manifold and property tuned Rochester will wake it up a little but still keep it a very nice cruiser. Keep up updated and lots of pictures.
Link to comment
Share on other sites

Austin I've seen your lemans and it's very nice. So often people cut up "base models" and go crazy on them. It's good to see an example of any every day car from back then especially with how clean and original it is. It may not be as fast as same year GTO but you will probably have the nicest lemans at any show you go to. My two cents is rebuild and make it LOOK as stock as possible. Adding an original pontiac 4brl manifold and property tuned Rochester will wake it up a little but still keep it a very nice cruiser. Keep up updated and lots of pictures.

 

this is somewhat what i was getting to. If everything is original, then it truly is not worth hacking the motor up just for some HP. Me personally if it was mine, i would freshen the motor up, and drive it.

Link to comment
Share on other sites

Do I have another toy? Yes I do, unfortunately several of them.

Do I show the car? Yes I do, though I work a ton during the show times I try to get to 4-5 shows in addition to the one I run every year.

Do I plan to sell the car? Impossible to say, in the near future unlikely. I have issues with disconnecting from cars which is why I already have a fleet in my early 30s. Were an offer come up that was hard to refuse you never know. But I DO love this thing.

 

As it sits other than the paint being redone, new roof and a recored radiator she's basically 100% origional and stock.

 

What I guess I have kicking around in my head is this. The Pontiac block that's in this thing is the same one they used from the 350 to the 455 so has PLENTY of room to bore and the option to put a 455 in a LeMans was available in 71. So taking this one up to a 455 and "Optioning Up" would still keep it in the realm of what it could have been from the factory. Obviously some other modifications would be needed with carb/intake/cam and exhaust to support what we did internally but would that be frowned on from the greater car community?

 

I KNOW seeing the latest episode of Street Outlaws which Big Chief is using a 70 version of the same car to build his Crow car has made this itch return. Obviously I'm not looking to THAT over the top but....aw hell IDK.

 

Good Guys is coming up in 2 weekends and I once again will be there with the LeMans. Typically speaking of the crazy collection of cars there I'm one of the only LeMans there that haven't been badged and modded up to GTO or GTO+ status so that's something I enjoy. To think, this car was something mom would use to go to the grocery store back in the 70s.

Link to comment
Share on other sites

  • 4 weeks later...

Ok this doesn't answer any of your questions, but as someone who once drove a 400 built to factory ram air 1 specs as a daily driver within the last 10 years maybe I have some insight about some budget things that make the car better.

 

I am assuming you lemans has either a small journal 326 or small journal 350 as stock, correct?

 

Pontiacs are notorious for "overheating issues". Most people don't know this but the stock overheat idiot light doesn't come on until 240-260 degrees (there is a very loose tolerance in the stock sending units). They like to make power around 180 degrees (160 is actually slightly too cold for the combustion chamber, at least that's what my best dyno pulls tell me). A flowkooler water pump makes a huge difference, esp when you switch to a stainless water pump restrictor and then reduce the tolerance between it and the impeller. I personally went to a aluminum radiator but a stock harrison 4 core will work fine if you have one that isn't corroded/plugged up. I went with one of the stock looking aluminum ones from Rodney Red but there are cheaper cross flows for your year that work great and will look almost stock.

 

Ignition, my points were giving me fits. Switched to a pertronix and a MSD digital 6 and the car smoothed out completely. I had a factory RAI cam in it which has the worst idle qualities of any stock pontiac part and where the thing would stall at traffic lights it didn't after that. However the best piece I ever put in the car was a billet distributor hold down from Nunzi in brooklyn. Most people don't realize but even the stock low comp cars have distributor walk. The stock hold down is a chincy pressed steel part and goes flat and lets the distributor creep. Seriously take a timing light to your car right now and I bet ya it is a few degrees out. Nunzi's piece is billet - he used to have it on his website but now you have to call him to order one.

 

Heads. There are a million pontiac castings and few are actually high performance. See if you can find a set of decent early heads to run on your car. I have had good luck with 670 casting heads, they are a 1967 only head for 400s, but they were the early RAI heads until the 97 round ports came out. On a 350 they will net you about 9.5:1 compression and require a chamfer to the top of the cylinder for valve clearance but it's a big jump. If you can find some later 7H1 or 4x and 6x heads as they require less work. Using stock pontiac heads means that only the hardcore poncho people will spot that it isn't stock.

 

Exhaust manifolds: get a set of factory style ram air exhaust manifolds. A superstock racer friend of mine ran my RA1 reproductions on his flow bench against a set of D pot tube headers and the cast manifolds blew the headers out of the water. Pontiacs have exhaust flow problems to begin with so any increase in flow in this area is a godsend. Ram Air Restoration sells them. Again, if you lift the hood at a show, only those that "KNOW' pontiacs will spot it, everyone else will be impressed you kept the stock manifolds.

 

Carb: While I am a devout fan of the quadrajet (or quadrabog as people love to remind me) and ran a 1969 GTO RA IV blue dot one on my 67 for years, they are probably the worst carb to live with. They are finicky, sensitive, and prone to air leaks. Currently mine has a float bowl leak (it drains back to the tank) that makes starting the car from cold a 10 minute process. A decently tuned holley with vacuum secondaries makes life easier. It's really easy to overcompensate and go too large so pay attention to cfm (a decent 450cfm carb should work fine for your 350). It won't look stock but put a big stock dual snorkel air cleaner on it and don't take it off at shows and nobody will notice. Electronic choke is also really really nice to have.

Link to comment
Share on other sites

 

What I guess I have kicking around in my head is this. The Pontiac block that's in this thing is the same one they used from the 350 to the 455 so has PLENTY of room to bore and the option to put a 455 in a LeMans was available in 71. So taking this one up to a 455 and "Optioning Up" would still keep it in the realm of what it could have been from the factory. Obviously some other modifications would be needed with carb/intake/cam and exhaust to support what we did internally but would that be frowned on from the greater car community?

 

 

While the block size didn't change the crank journal size did, also the cylinder walls are not the same for all blocks. There is a limit to what you can do and boring a 350 to 455 is outside those limits (i think the biggest you can go is 413ci). Those blocks are all thin wall casting as well so some of them are more fragile than others. What is nice about the pontiac engines being externally all the same size is that you can go find a 455 pontiac block and "dress it" to look like the stock 350 and unless you are looking at casting numbers it will be very hard to tell. Also you don't have to move the engine mounts like you do on a chevy going from small block to big block.

 

People tend to think the blocks are all the same but the really are not.

 

400, 428, and 455 blocks tend to have the greatest aftermarket support. you can build a 400 all the way out to 466ci (stroker crank) if you feel so inclined. 400 blocks tend to be the most common as they were in nearly everything.

 

Honestly, if the car is a cruiser and not a bonefide stop light sleeper, just do a few mods to wake up the 350 you have. It's really easy to make a Pontiac a miserable place to be due to the heat sensitivity (ever drive with the heat on in NYC traffic in the middle of july? it's awful). Plus you can always put it back to 100% stock at any time if you decide you want to go the show car route.

 

BTW, if you are going to go big or go home then I suggest you find a wrecked LS2 modern GTO and rob its drivetrain and FI. Then bolt on a supercharger and never open the hood. It will never be cheaper to built a 600+ hp pontiac engine that it would to pluck an LS2 from a yard. Honestly my RA 1 clone car dyno-ed at 350hp at the rear wheels and was good for 12 seconds on bias plys but it was not for the faint of heart to drive everyday.

Link to comment
Share on other sites

BTW, something you aren't thinking about is the chassis. So let's just say you magically find a way to get 450 rwhp into the car tomorrow without a single chassis mod. How much do you think the car will twist? wheel hop?

 

If the lemans truly is stock it will have an frame with open C channel rails (you can crawl under the car at the door and look and see if the frame rail is open). It will also have open c channel control arms in the rear. While there are kits to box the frame rails and replace the control arms with boxed ones or billet alloy ones or fully adjustable ones (I like the metco ones myself) it kinda kills the originality of the car to box the frame. Then there are traction bars, sway bars, decent wheels and tires, springs, shocks, and if you really want to get nuts front A arms with improved ball joints if you want to toss it into a corner at 80mph.

 

Honestly, set your goal to be about 350rwhp. properly setup you should be able to run the car on the stock rally II wheels and tires to a decent 1/4 mile time. a set of boxed control arms and some decent bushings and the car will be all the fun you could want out of it. before you do anything have the car dynoed in it's current config, if it is pushing more than 190hp to the rear wheels I would be surprised. Also do a compression test and find out if you need to go up a bore size.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...