[Jack Gifford]

Yeah, each of us has his own "pet" engine size, whether it's in-the-flesh machines or just dreams. Here's one reason I can dream up a multitude of exciting projects limited to about 400 inches: Take a close look at what the Poteet & Main streamliner did at Bonneville last fall with a single 347 c.i. engine- a one-way run of 462 MPH, which is within ten MPH of the unlimited wheel-driven record!

I've always enjoyed Pontiac's "single V8 engine design of 287 - 455 c.i." since first messing with one in 1959.

[john marcella]

Originally Posted by slowbird

Now that would be really impressive, 3.1hp/cid is getting it done NA.

Im pretty dam sure 3.1 has never been done N/A with a 2 valve head. With anything at any CID.
With a Pont-good luck with that

[mike leech]

Originally Posted by john marcella

Im pretty dam sure 3.1 has never been done N/A with a 2 valve head. With anything at any CID.
With a Pont-good luck with that

x2!

[Half-Inch Stud]

X Dit. Oh whatever.

seems to me a Summary thus far would emphasize PRACTICALITY over PRIDE to:

Take a best of breed BBC assembly &

Pick a Hi-Rise dual-plane manifold, and an alternate Dominator Flange. also the favored Dual-quad, EFI manifolds.

Then pick/make a Valley pan happen. The PMD top-end hard-parts is done.
==========================================

pick the BBC block (iron, aluminum) and MODIFY the oil mount, Bell Flange, Timing Cover( at least have the parts available if desired), perhaps oil pan. And choose Internal Balance.

pick the BBC heads (iron, aluminum) that appear Ram Air V like. PICK the LARGEST 3" diameter Intake valve as thee PRIORITY of such a BBPMD effort. add styled Valve covers to appear PMD inspired.

1000HP NA will occur like falling off a log, with flat HYDE liftersq, while the roller am race version will be state of technique.
================================================== ===
it is finished. - Jesus. (hey it's Easter today)
done.

Geez, even I'd consider doing this, after comparing MCCarty's Ram Air V suite ( and it is sweet). Personally, I want to select the largest slug diameter, with A strong regard for factory stroke or a little more.

(IPAD auto-text-correct stinks. Gotta turn it off)

bring on the impracticality of this approach, trade-off.

[65nss4spdGTO]

Originally Posted by Jack Gifford

Take a close look at what the Poteet & Main streamliner did at Bonneville last fall with a single 347 c.i. engine- a one-way run of 462 MPH, which is within ten MPH of the unlimited wheel-driven record!

Take a close look at that 347ci engines parameters and the design.

The Pontiac engine as designed as Milepost said, "Tweener". With the bore space limitation, comes the bore size limitation, then the cylinder head valve size. The original design was to move heavy street cars in a low RPM operating range. The Quest (no pun intended) for increased power will always come with a price, moving the RPM range higher. Bigger bores, shorter strokes, lower deck heights, compact induction systems. All of the requirements to go beyond the point we are today.

Calvin Hill
Hill Performance
708-250-7420

[GTOGEORGE]

This is one of the silliest threads I've seen, I can't believe someone even started it! First, yes Pontiac did quit installing REAL Pontiac engines in a production Pontiac back in late 70's BUT Pontiacs are FAR from DEAD!i I went to Detroits Autorama back in March there were at least 3 NEW versions of a Pontiac Trans Am (based off the New Camaro body) there and one for a GTO that you could buy (given you have enough CASH)................how cool is that, YES they didn't have REAL Pontiac engine in them but you have to start somewhere. People just won't let Pontiacs Die! Go to Norwalk in August, BAM........over 500 Pontiac Race cars and over 500 Show cars! Go to a NHRA National event and REAL Pontiac Powered cars are still winning the Stock/Super Stock Classes.
2nd, as for moving the bore spacing to make MONSTER engines 90% (just a guess) of the Pontac Racers haven't rung out all the Power a Pontiac engine can make with the standard Bore spacing, they just add another Nitrous kit or squeeze in more Boost or just switch to a JUNK Chevy engine...................Very Impatient Racers. YES, It would have been nice if the Pontiac engine had a longer bore spacing or more head bolts (BUT it Doesn't) or if WE didn't have to WAIT for some guy out of garage to make us Aluminum heads instead of holding our breaths for a BIG Company like Edelbrock to do it. The 3 heads that Edelbrock has come out with are copys of other Pontiac heads (Classic E-Head, their version of the High Port and or Tiger head and a D Port-Head), what the hell are there so called engineers doing .............oh yea designing new Chevy heads! Thank God for the Small guys (KRE, Wensler, Roland, McCarty, DC, AllPontiac, ETC.)
Unless you're name is Tony Shumacher there is always going to be someone Quicker & Faster, it's called MONEY! If a Racer back a LONG time ago can make 1,600+ HP with steel heads and a stock block on a REAL Pontiac engine I'm sure if we keep putting our heads together we can MOVE Mountains!


Thanks,
GTO George

[mike leech]

[QUOTE=GTOGEORGE;4600759]This is one of the silliest threads I've seen, I can't believe someone even started it!

Ditto. This is a story about unicorns and fairy tails. No point. We have real parts available that aren't being utilized.

[Badbird69]

I like how Tom V. thinks. You can tell by his thoughtful presentation and choice of words that he has learned how to navigate the corporate mine fields.

I, for one, would LOVE a 4.8 BS block (with a few more head bolts). At non-Pontiac events we are typically giving up 100 cubic inches or more - and there is no "moral victory" in losing. You just lost. So we turn up the power and hurt more parts trying to stay competitive. Well, that costs money too.

At this level of racing, all the parts are already custom - and at least a stretched block would still LOOK like a Pontiac. Sign me up!!

Dick Fulton

[J.C.you]

I agree with George, the potential of the old poncho at its current bore space is NOW going to move forward with the addition of a couple of new head castings. And it AIN'T the pro port. The Warp and further development with the CV will up the bar we somewhat enjoy now.

Further tweaking of the current bore space block already alluded to will move us forward.

[Dragncar]

Taking a Sonny Leonard giant BBC and putting Pontiac on it would be the lamest of the lame. Ultra DB move.
I keep going back to that 1970 SOHC 427 Hemi. The Ford guys copied it and made their mod engine and they have been getting crazy power out of it for awhile now.
If some Pontiac loving Lotto winner finished if with more modern tech it would make more power than the Ford engine simply because it is larger. That would be as far as you could take a Pontiac bore spaced engine for power. No one could not call it a Pontiac, because it was one in the first place. ( I would do a shorter deck)
If I had 250Mil net sure I would do it. All it takes is money and you can build anything right. It would be crazy sure, and it would not make money. Whats 5 mil if you have 250 and never had money before.
But it would be the coolest thing ever and some of you nut jobs would buy it and race them. Not sure in what class though.
No one thought in a million years we would have the Pontiac race parts we have today, ever. But we do so its not all that crazy.

[Tom Vaught]

Just to clarify what the post was about, for some of the people who missed the point the first time, the post was about DURABILITY. Thin Cylinder Bridge makes for poor Engine Durability, it is a fact.

A Typical BB Chevy Engine can be raced for 300+ passes at a high level of competition with very little work other that routine oil changes, etc. What gave the Chevy engine that capability? A Durable engine at a high power level.

Ok, there might be a couple of guys out there who can run a whole season with a engine capable of winning the event in the Pontiac camp, maybe.

Some guys can run Low Boost or HP for years and be perfectly happy with what they have. My post was in reference to the guys who actually need the extra bolts for their efforts to keep the heads clamped down, run a couple of seconds faster vs the low boost guys, and who would be even faster if they had a more durable engine design.
(Gasket Sealing being one example).

I pointed out the FLAW, nothing more. You can take it for whatever you want to do with the topic.

I will say this, SOHC 427 Hemi heads are not coming no matter how much you dream, at least in the next 10 years unless you copy the FORD 427 SOHC Engine (which by the way was designed at least 2 years before the Pontiac 427 SOHC was on the drawing board). I could take a repop FORD 427 SOHC engine (made by a few Ford guys) and adapt the heads/chain-drive to fit on a IA-2 Block in 6 months given the cash. The parts are out there. Would it be a Pontiac 427 SOHC engine, NO.

Bolting on a Ford SOHC engine head and camshaft drive system would not be any different vs bolting on a CV-1 Head or a Tiger Head, neither head looks like a STOCK Pontiac Head so what would be the difference SOHC vs the RA-V head swap?

I was a member of the Team that made 1600 hp with cast iron heads and a 1967 block in 1996. We made the number before anyone else even thought about doing it, thanks for reminding everyone that I have been in the game a long time George.

Tom Vaught

[John Langer]

You want a bigger bore spacing block. Buy a dart bbc with out head bolts and cut and move a pontiac head to fit the bore spacing. If there is a sheet metal intake on it I assure you that only the trained eye would know what block it is. CFE can do the head mods. Just sayin'...

[Tom Vaught]

Originally Posted by John Langer

You want a bigger bore spacing block. Buy a dart bbc with out head bolts and cut and move a pontiac head to fit the bore spacing. If there is a sheet metal intake on it I assure you that only the trained eye would know what block it is. CFE can do the head mods. Just sayin'...

Totally Agree, John. If you were running a Belt Drive and a Front Plate, even fewer people could tell the difference. They would see the Pontiac Head Castings and say "Pontiac Engine" but might not pick up the "spread bore", (especially on a special CV-1/ RA-V type head).

Tom Vaught

[Travis Q]

I fully agree that the more material between cylinders, the better the head gasket sealing. This is especially true on the Pontiac with it's head stud layout.

But I have tuned a LOT of boosted 632's that run WAY over 40 psi. Those babies are 4.600 bore diameter on a 4.84 bore space. Not much there for sure! But, with the right gasket arrangement, they seem to stay on just fine.....

My opinion is that bore spacing is king. There really is no replacement. It's sort of a domino effect....you cant have a big bore without it, you can't have big valves without a big bore, you can't have big runner CSA without big valves (well, I guess you could, but...). It has the most effect on a naturally aspirated engine, but you can see its overall effects on a boosted engine as well, especially in engine acceleration rate vs. horsepower....

This is why there is so much interest in big bore space boosted applications. It gives the ability to run the bore size way out, decrease the stroke, and spin the engine to big rpm levels: I know of one particular example of a 5.300" bore space Hemi that spins over 11,000 rpm. Certainly one way to move air through the engine!

As far as the 5.500" Bore space engine, it has already been done. It's development resulted in the cuurent ADRL rule limiting bore spacing to 5.300".

[Tom Vaught]

Agree, Travis, maybe with a "Spread Bore" block we could get away from some of the need for 18 bolts to clamp down the Traditional Pontiac Head with boost.

Hope you had a great Easter Week-end!

Tom Vaught

[Tom Vaught]

Thought of another story on this "Bore Spacing" deal.

A few days ago, as many of you know, I went down to help John Clegg with his "Rat Rod" 64 LeMans that was running in the Texas Mile. Basic Pontiac 455 type 2 bolt main block engine with a Vortech Supercharger and a little hydraulic roller camshaft runs 180 mph in the Mile.

While we were there he shows me his RACE CAR and its Engine. (3rd Gen Firebird)

Now John Clegg has been a Pontiac Racer for longer than 95% of the people on this board have been alive. I personally saw his 64 GTO, His 455 SD car (former HO Racing National Record Holder), and other cars.

So back to the RACE CAR. His RACE car has a 450 cid engine. It runs 7.90s NATURALLY ASPIRATED, (This is not a 535 CID Supercharged engine/car trying to get into the 7s, it IS in the 7s.) He is not Trying, his car/engine is there.

1) We have an engine that is 85 cubic inches LESS displacement

2) We have an engine with 1.00" less stroke

3) We have an engine running GAS with Dual Dominators.

So what are the other differences:

A good set of heads, not the best heads but decent heads.

A Big Bore Spacing Block and a 4.696" bore piston

A Short Stroke (3.25") crankshaft.

Everything that Travis just mentioned above minus BOOST and the boost is coming down the road.

So here you have a properly designed engine using later GM Knowledge (all of the basic parts are GM Part Number parts) to have a FAST car that is quicker in the quarter mile vs the 535 Supercharged car using technology from the 60s.

Think about it.

Tom Vaught

[Elarson]

Lot of valid points made by all.....plenty of approaches.

Much has been made of the (10) head bolt configuration over the years and it's been mentioned here. They are a big limitation for head sealing if your heads are flexible. The bolts are strong enough....it's a matter of the head being stiff enough to bridge across the span between bolts. Worst configuration is a stock size, water-jacketed aluminum head. Anything to make the heads stiffer improves head gasket sealing. So far, we're getting excellent sealing with our 10-bolt billet funny car heads but they're massively stiff compared to something like an e-head. Stiffness is improved by:

taller heads (Tigers better than e-head, for instance)
cast iron is stiffer than aluminum
eliminate water jackets
thicker deck material in the head

Food for thought,
Eric

[Tom Vaught]

I would forget about the big bore spacing block if I had access to a set of your heads Eric!!!!!!!!!!!!

Tom Vaught

[Elarson]

Originally Posted by Tom Vaught

I would forget about the big bore spacing block if I had access to a set of your heads Eric!!!!!!!!!!!!

Tom Vaught

Got your checkbook handy?

They've been a great engineering project.

Eric

[GTOGEORGE]

Now to get back to the origanal thread.......there is nothing wrong with a larger bore spacing, the problem is when you do that the engine quits being a Pontiac. I for one love racing my Pontiac, the engine has been together for 4 years now (over 200 passes) with the heads only coming off once. Not bad for a low 8 sec. (now high 7's) car. We (Pontiac) have a N/A car that will be in the 6's and there is a good chance we will have a Blower/Alcohol car in the 5's this year pretty darn good for old school junk! Like I said earlier we have so much more to learn about the Pontiac engine without making a white elephant out of it.

GTO George