Pontiac V8 H-Body

[NixVegaGT]

I haven't had a chance to get back to this for a couple days. Tom, your new avatar is AWESOME!!!

I think the next step is to find out what some custom machine work will cost and what's possible. I'll get a hold of my machine shop and ask them what the machine limitations are to overbore. I'll get costs while I'm at it.

Can one of you guys research what it costs to get some aftermarket heads? Which ones are best and how much. 400 heads? 350?

See if we can find one of or parts for those '50's engines. That 3.25 stroke seems really nice to me if we can make it work. I'll do some digging into this myself. I think if we can make one of these work it will reduce cost of machining.

How plentiful are 301's?

So the next step is feasibility and cost. It may not be worth it after that. BUT it might work. I think it'd be cool but it's a gamble. It goes into Tom's car and we see if it breaks...

Tom, did you mean you've got an article on some guys who've done this already? A stroked 301?

[barebonesracecars]

There are at least 3 manufacturers making aftermarket aluminum Pontiac heads...Edelbrock, Kauffman, and Wenzler, I believe. Cost is around $1300/pair. Edelbrock seems to be the consesnsus best....they come in 2 different c.c. sizes.

301's are (or were) fairly plentiful....used in Firebird, T/A, GP.

[SunbirdMan]

Everytime I read this thread I get to thinking about a pontiac V8 for my Sunbird. Does anyone have an overall length from trans to fan? it looks like it would require a radiator relocation.

[NixVegaGT]

That's my bet, Roger. The bore spacing is quite big. 4.625" I think. The SBC is 4.4". It's got to be bigger... Thanks for the numbers/manufacturer for the Pontiac heads, Reid. That's not too bad. Might be able to find a deal somewhere...

[NixVegaGT]

I found some Edelbrock heads on Ebay:

http://cgi.ebay.com/ebaymotors/Edelbroc ... 0152137399

There is already 11 bids! Aluminum heads could be put at the end of the list if money is a problem. $1300 is some coin. I think eventually it's worth it to reduce the weight. There are a bunch of heads to be had on Ebay that aren't expensive:

http://cgi.ebay.com/ebaymotors/PONTIAC- ... 0145976186
http://cgi.ebay.com/ebaymotors/65-66-PO ... 0158392601

The stock 301 heads are going to be a BIG limiting factor. I'd say that if you're good with a grinder and have some time you could increase the port volume a bit but I don't think they are worth the time and money.

To relent on 16 lbs. for the short term may be necessary for money challenges. It's going to take money to modify the crank for the block... If money is not a problem then the Aluminum heads are a big weight savings. I like those Kaufman heads! The 65cc heads go for $1195. Could get dished pistons to reduce the compression...

http://www.krepower.com/dport.htm

Off to do more research.

[res0o7eb]

Good work everybody.
I appreciate the research, Nic. It is extremely interesting to come up with a lightweight Pontiac V-8 that that has some power and won't self-destruct if revved beyond 4500 RPM.
Keep in mind that the 301 is EXTERNALLY balanced, so eliminating the weak crank for a stronger internally-balanced one solves a lot of issues.

Building a Hipo Pontiac - Chapter 2:
http://72.14.253.104/search?q=cache:jxu ... a78ch2.pdf

Here's a list of factory Pontiac heads:
http://www.angelfire.com/on/geebjen/heads.html

Here's another list of Pontiac crankshafts (very similar to the angelfire link only in human readable white background)
http://fiedlerh.home.att.net/PontiacCranks.htm

HeadFlow Data (yah, big is not always better)
http://users.erols.com/srweiss/tablehdc.htm#Pontiac

Page 79 from the Ultimate American V-8 Engine Data Book (By Peter C. Sessler):
http://books.google.com/books?id=KD23-W ... 8#PPA79,M1

I may be able to get a complete 350(354 c.i. actually) Pontiac engine. I'll try to compare dimensions of the 301, 354, and a 305 Chevy (it's got Pontiac blood in it - it's from an 84 Firebird. Did I mention I got it free?). And take some measurements of my Astre and Sunbird (for Roger).

[patrick1151]

Hey I had a friend years ago that took and 80 or 81 firebird with a 301. When he finished with that engine, he could beat just about anything on the street. His goal was to beat a lady he knew of who had a very very fast corvette stingray. Never heard if he did beat her but there must be performance parts out there for the 301

[NixVegaGT]

Great input, Tom. When I get some time this weekend I'll do some ready. In the meantime I'll see if I can post those crank mod costs too. Good work guys.

Thanks for the post, Shannon.

[res0o7eb]

Here's an interesting development:
A new Pontiac head called the CV-1 (Canted Valve).
It uses a Ford casting or something.


BUT ... they say to use this Ford 351C manifold with intake spacers:

Because the manifold is designed for a 9.2" deck height block. Pontiac deck height is 10.23(or10.25).
http://store.summitracing.com/partdetai ... toview=sku
This basically a racing setup - and it's expensive - but could it be bolted on a short deck Pontiac 301 block?

More info here (again, another automotive web site with unreadable white text on black background!?!):
http://www.angelfire.com/fl4/pontiacdud ... 1head.html
... and here:
http://rolandracing.com/id66.html

[spyder_xlch]

If it's designed for a 9.2 deck height and a 301 is 9.1something it may work. Why don't you send me a 301, those heads and intake and I'll try it.lol

[NixVegaGT]

WOW. Those are pretty hot heads. LOL good one, Matt.

To be honest, it's quite a bit more than you need. You already know that though. I really like the development that went into the design. Really thinking well. The intake valves are HUGE! Damn. It's a bit of a bummer because it would work out so well for the deckheight.

Nice find Tom.

Have you busted down that 301 yet? It would be good to know what the width of the big end on the connecting rods is.

I got numbers from my machine shop:

Offset grind for new stroke: $500
Grind mains: $100
Heat-treating: $60
Balance: $200-350 (depending on the change in weights.)

So about a grand... Not all that bad for a custom crank though.

SO the early crank, if it works, would be the best option I think. The cheapest anyway. Maybe we could find one at a swap meet or something... I gotta stop saying WE. SOrry dude. I'm just pretty keyed up about this idea.

[res0o7eb]

Keep in mind, any Pontiac in any H-body is cool. Lots of stuff available for Pontiac V-8. Not cheap, but reasonable considering the power potential.

Wow, $500 to offset grind. Forget it? 3.75 stroke, then. If it doesn't interfere with anything in a shorter deck block.

No, I haven't broken down either 301, yet. One is down to a shortblock - a few cylinders are rusty, though.

I am expecting the width of the 301 rod to be the same as all other Pontiac V-8 rods. I think the rod bearings are the same - nope. Same as the Buick 300,340,350, though.

Here's a reference to some rod dimensions:
http://www.301garage.com/Jim_P/301tech.html

Rod length 6.040
big end width .900
big end bore 2.125
pin bore .927

I found another document that states the main bearing jounals of the 287 crank at 2.50 dia. - same as 301. But, it doesn't mention anything about a forged crank. It's in the SIA #181 Jan/Feb 2001.

I am working on acquiring an early crank - I hope to have it in my possession in a couple of weeks.
I have another local inquiry that resulted in a lead on an early short block. They ARE out there.
301 engines are actually fairly easy to find - cheap. So are 354 Pontiacs.

[res0o7eb]

Hmmmm .... This link says that the 301 has 3.00 main journals
http://www.301garage.com/Jim_P/301tech.html
and this picture of a 301 crank looks to verify that ...

The attached picture of a couple of 301 cranks from ebay look to further verify that.
Only one way to know for sure ... pull the oil pan, Tom!!! Duhh??!!??
I'm out of town until Friday - will definitely do it this weekend.

[NixVegaGT]

Wow those cranks are really weird looking. You already found an early crank! WOW cool. When do you get it? I've been searching all around here. No luck. It would kinda piss me off if the mains are actually 3". I think the 3.25 stroke would be cool.

SO on to the 3.75 stroke right? OK. hmmm. Let's see...

Chevy rods: 5.7"
Chevy pistons (see below): 1.56"
3.75 stroke/2: 1.875"

Total: 9.135
If the numbers are to be believed that the deckheight is 9.143, that's a nice 0.008 destroke. OR damn near zero after milling the block for straightness.

4.00 bore x 3.75 stroke. That's 383 right? COOL! So on to pistons, Silvolite part #: H3437 is the piston I found. Very nice piston, and not too expensive. Here's a couple links to them:

http://www.beckracing.com/slvpg29.htm
http://www.jegs.com/webapp/wcs/stores/s ... ogId=10002

This is super HOT. OK I guess I was wrong I kinda hope the mains are 3" now. The rod ratio is a bit sucky: 1.52... well a lot sucky. BUT it isn't that far off from the CBB 454 right? Good stuff, Tom.

[NixVegaGT]

Do you think we could make a girdle like the ones they use for the SBFs? It goes in the lifter galley. You could just run the engine with no support and see how long it lasts... That's so the engine doesn't do this:



Here's what they look like:



With a rod ratio of 1.52 it will be REALLY torquey and not so able to make rpm power anyway so set the redline at 5k of even lower. I'm sure it'd have more than enough power at the low end to make it fun to drive.


With 383 ci those hot heads might not be out of the question. Really expensive though. I'm thinking it will take that intake with some port matching just fine.