[ho428]

Originally Posted by Stan Weiss

Having work with Chrysler raw bore blocks many years ago. My question would be what is the minimum bore that this block would clean up at?

Also what would be wrong with going 4.12" bore and 2.84" stroke like Pontiac did?

Stan

The 4.0 x 3.0 that SBF and SBC use works a whole lot better, and it's going to require a custom crank either way.

[Stan Weiss]

Originally Posted by Robert C.

This chinezze math?


Because it is a 45 deg. block every thousands you go down the heads get closer together. The valley pan sits on the intake surface. Right?

Based on a couple of thousand year old Greek math.

Since it is a 90 degree v the distance between the 2 sides (hypotenuse). Is the square root of the 2 sides squared and added to each other.

Stan

[Stan Weiss]

Originally Posted by ho428

The 4.0 x 3.0 that SBF and SBC use works a whole lot better, and it's going to require a custom crank either way.

My memory is not what it use to be. I know AMC did very well in Trans Am racing. Didn't AMC use a large than 4" bore and shorter than 3" stroke in Trans Am back in the day?

Stan

[Robert C.]

Originally Posted by Stan Weiss

Having work with Chrysler raw bore blocks many years ago. My question would be what is the minimum bore that this block would clean up at?

Also what would be wrong with going 4.12" bore and 2.84" stroke like Pontiac did?

Stan

The cylinder cores are sized for a clean up at 4.150 if we are lucky.

Are we never happy with what is out there? Ha ha.

You can sleeve it to what ever you want too.


BTW.

One SHORT DECK left in stock. We will need 4 more orders after this one before they are available again. So if you are think of one, now is time to pull the trigger.

[tom s]

Just for information,a true pontiac short deck block(9.2) uses a smaller valley pan.the 301 and the short deck 303 are examples.I used 301 valley pans on both of the 303 short deck blocks I have built.Tom

[Tom Vaught]

Originally Posted by Robert C.

You got a 4.180 bore block. And the sheet should be in the crate.

Thank you Robert, Very Much. No more Johnny Trips to the UAW site for me.

Tom V.

[Jack Gifford]

As far as a "pushrod cover" for shortdeck blocks- we need to know the configuration of the curved "dips" in the block's front & rear webs, before talking about how to cover the valley. Are the dips of the normal Pontiac radius, simply moved .728" closer to the cam (1.030" x cos 45 degrees)? Or are they of a larger radius, leaving the base of the valley the normal distance above the cam?

[I've never laid eyes on any shortdeck Pontiac, either by PMD or by AllPontiac]

[Robert C.]

The radius are the same as a normal IA II.

[ho428]

Originally Posted by Robert C.

The cylinder cores are sized for a clean up at 4.150 if we are lucky.

Are we never happy with what is out there? Ha ha.

You can sleeve it to what ever you want too.

While I am grateful for the aftermarket block offerings I can only be happy about what is out there if it suits my build purpose, which is a true 303 cu in that can compete against the SBF and SBC.
The original Pontiac did not and will not in a long block 7" long rod configuration, nor will I spend 20-30 grand to prove what I already know.
A short deck 4 x 3 at least has a chance even with the larger main and rod bearings.
A custom intake will have to be made, a dry sump system put in, billet crank, custom pistons. While I've finally gotten over the cost of the crank, sleeving a brand new block? Don't think I could stomach even the thought of that.

Even though this video is about my friend Mike getting his 383 Corvair hammered by a Porsche at Road Atlanta a couple weeks ago, what I want you to notice is the tach and sound of the 302 SBF in this Mustang filming it.
This is T11 at Road Atlanta, we all "short shift" coming over that hill, notice what his short shift RPM is, it's beyond my redline. His redline is over 9000

https://www.youtube.com/watch?v=w1-2M97Ar3c

[Elarson]

Originally Posted by Stan Weiss

Bob,
Is there something about the valley pan that I am missing?

► ((10.23)^2 * 2)^.5 - ((09.20)^2 * 2)^.5 = 1.45664

Stan

Your math is correct if your milling cutter is taking material off the valley cover traversing laterally.

Bob's math is correct if your milling cutter is traversing perpendicular to the 45 degree angle of the intake side of the head.

Same result either way.

Eric

[Elarson]

Originally Posted by ho428

While I am grateful for the aftermarket block offerings I can only be happy about what is out there if it suits my build purpose, which is a true 303 cu in that can compete against the SBF and SBC.
The original Pontiac did not and will not in a long block 7" long rod configuration, nor will I spend 20-30 grand to prove what I already know.
A short deck 4 x 3 at least has a chance even with the larger main and rod bearings.
A custom intake will have to be made, a dry sump system put in, billet crank, custom pistons. While I've finally gotten over the cost of the crank, sleeving a brand new block? Don't think I could stomach even the thought of that.

Even though this video is about my friend Mike getting his 383 Corvair hammered by a Porsche at Road Atlanta a couple weeks ago, what I want you to notice is the tach and sound of the 302 SBF in this Mustang filming it.
This is T11 at Road Atlanta, we all "short shift" coming over that hill, notice what his short shift RPM is, it's beyond my redline. His redline is over 9000

https://www.youtube.com/watch?v=w1-2M97Ar3c

I love videos like that. I follow your stories closely and someday I'd love to build a road race car. A couple of questions:

1) WTF did the Porsche driver do that for? I couldn't understand why he shot over to the left. It didn't look like a normal competitive line. Maybe I'm missing something?

2) It looked like the car in the video shifted at 7000 rpm, didn't it?

Eric

[slowbird]

For some reason i thought the deck height on the IA short deck blocks was 9.7, but its 9.5??

[ho428]

Originally Posted by Elarson

I love videos like that. I follow your stories closely and someday I'd love to build a road race car. A couple of questions:

1) WTF did the Porsche driver do that for? I couldn't understand why he shot over to the left. It didn't look like a normal competitive line. Maybe I'm missing something?

2) It looked like the car in the video shifted at 7000 rpm, didn't it?

Eric

1) Because he's a Porsche driver and stunts like that are pretty typical of them.
He got 6 months probation, should have been suspended IMO, but Mike parked his car, threw a tarp over it and may not rebuild it. That's the true hard price that gets paid when someone does something stupid in Vintage racing.

2) Yes, he short shifted at 7000
I've been top ended at Sebring by a 302 turning 9500, hurt my ears when he went by.

[hurryinhoosier62]

Originally Posted by ho428

While I am grateful for the aftermarket block offerings I can only be happy about what is out there if it suits my build purpose, which is a true 303 cu in that can compete against the SBF and SBC.
The original Pontiac did not and will not in a long block 7" long rod configuration, nor will I spend 20-30 grand to prove what I already know.
A short deck 4 x 3 at least has a chance even with the larger main and rod bearings.
A custom intake will have to be made, a dry sump system put in, billet crank, custom pistons. While I've finally gotten over the cost of the crank, sleeving a brand new block? Don't think I could stomach even the thought of that.

Even though this video is about my friend Mike getting his 383 Corvair hammered by a Porsche at Road Atlanta a couple weeks ago, what I want you to notice is the tach and sound of the 302 SBF in this Mustang filming it.
This is T11 at Road Atlanta, we all "short shift" coming over that hill, notice what his short shift RPM is, it's beyond my redline. His redline is over 9000

https://www.youtube.com/watch?v=w1-2M97Ar3c

Excellent post! The Pontiac 303 Trans Am engine was an absolute debacle when compared to the 302 SBC and the Boss 302. That is why accountants should NEVER have a say in engine development.

[tom s]

Actually the 303 shortdeck engine ran good enough to be told not to bring it back.The std deck 303 was a dog.Shaver engine is building the Titus 303 shortdeck RA V to put it together with the Titus car.Tom

[ho428]

I believe is wasn't usable as it was very limited numbers and not a production engine like a 302 Ford or Chevy, not that it donkey stomped them.
Even today with all our aftermarket parts, try and build more than a one off vs building a 302 Ford or Chevy.
Pontiac aftermarket is big cube drag race oriented, I've reluctantly accepted that.

[tom s]

They only made 25 complete engine.I have a pic somewhere with all of them on crates,smog pumps, carbs etc.SCCA said they needed 100.2 1/2 mains,dry sump provision ,filled in lifter bore area like a SBC etc.They also had a 2-4 Xram intake for both a V headed version and a RA IV headed version for 1969.Special tall tach drive dist to clear the 2-4 Xram intakes.Tom

[Stan Weiss]

Originally Posted by Elarson

Your math is correct if your milling cutter is taking material off the valley cover traversing laterally.

Bob's math is correct if your milling cutter is traversing perpendicular to the 45 degree angle of the intake side of the head.

Same result either way.

Eric

Eric,
Thank you for the explanation on why the different methods / numbers produce the same results.

Stan

[Tom Vaught]

Tom Nell and Herb Adams tried to run the 64 Tempest in Road Race Competition and while they were doing ok (performance wise) at Lime Rock before they hurt the engine, they really did not have a chance in that deal. The NASCAR 366 engine would have been a better engine and personally have seen that engine run 8500 rpm many times in the 70s.

Mike leech was doing that RPM with a lot larger stroke engine and was getting the engine to live.

The 303 just suffered from Lack of Support by GM and 1st Gen technology in the racing series.
By then Donahue and Penske were in Gen 3 and Gen 4 level parts.

Tom V.

[hurryinhoosier62]

Originally Posted by tom s

Actually the 303 shortdeck engine ran good enough to be told not to bring it back.The std deck 303 was a dog.Shaver engine is building the Titus 303 shortdeck RA V to put it together with the Titus car.Tom

Sorry, Tom. I should have been more clear. The short deck 303 was the one that used RAIV heads (?) not the tunnel port heads. It did perform much better than the std deck 303, but was still at a distinct disadvantage when compared to the DZ 302 and the Boss 302.