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Discussion Starter · #1 ·
Speedmaster seems to offer a number of products for Pontiac. They are out of Australia from my understanding.

Just got a note on this line of intakes and they list one for Pontiac. looks to be standard port size, not RA, and I don't know if it could be opened up for port matching for RA size. But what I note is that it has no heat crossover which some block off anyway. Seems to have a good RPM range and is for those who like square bore carbs, Holley & AFB.

Price doesn't look bad and maybe if you are looking for an intake, seems most suppliers are on back order on many parts and maybe these could be easier to get.

I am not affiliated or recommend Speedmaster as I haven't used any of their items, this is just another option that may work for somebody. It could be junk, but it may be a great piece. Most of the big name parts sellers carry Speedmaster items, as well as Ebay, so shipping should not be an issue.

 

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Speedmaster seems to offer a number of products for Pontiac. They are out of Australia from my understanding.

Just got a note on this line of intakes and they list one for Pontiac. looks to be standard port size, not RA, and I don't know if it could be opened up for port matching for RA size. But what I note is that it has no heat crossover which some block off anyway. Seems to have a good RPM range and is for those who like square bore carbs, Holley & AFB.

Price doesn't look bad and maybe if you are looking for an intake, seems most suppliers are on back order on many parts and maybe these could be easier to get.

I am not affiliated or recommend Speedmaster as I haven't used any of their items, this is just another option that may work for somebody. It could be junk, but it may be a great piece. Most of the big name parts sellers carry Speedmaster items, as well as Ebay, so shipping should not be an issue.

Damn looks nice wish I'd seen it before I like the way its open and it would be ez to seperate the H2O
 

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Almost an inch shorter than the EDL-7156. Nice intake and easy workings of separating the crossover! Not to hijack this thread but has anyone bolted these up recently? They are selling alot of them ebay, amazon.

 

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Almost an inch shorter than the EDL-7156. Nice intake and easy workings of separating the crossover! Not to hijack this thread but has anyone bolted these up recently? They are selling alot of them ebay, amazon.

How does that work? The crossover is left open on the heads?
 

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Discussion Starter · #8 ·
How does that work? The crossover is left open on the heads?
The RA IV uses a separate cast iron exhaust crossover that is independent of the aluminum intake. It can be used so as to heat under the carb/plenum just like any cast intake. But, it can be removed to keep heat off the carb/plenum (racer's trick). When not using the crossover, a plate can be fitted in place and the bolts/nuts that on the intake hold the plate in place. I looked to see if I could find an example, but did not see anything. Most likely it would be easy enough to fabricate out of the correct thickness steel or aluminum plate.
 

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The RA IV uses a separate cast iron exhaust crossover that is independent of the aluminum intake. It can be used so as to heat under the carb/plenum just like any cast intake. But, it can be removed to keep heat off the carb/plenum (racer's trick). When not using the crossover, a plate can be fitted in place and the bolts/nuts that on the intake hold the plate in place. I looked to see if I could find an example, but did not see anything. Most likely it would be easy enough to fabricate out of the correct thickness steel or aluminum plate.
so just a thin piece of sheet metal would do it? i assume between the gasket and intake? whats the disadvantage on a street car to doing this? i know the single plane intakes have it blocked off, im running a performer rpm and could cook eggs on the darn thing...
 

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Discussion Starter · #10 ·
so just a thin piece of sheet metal would do it? i assume between the gasket and intake? whats the disadvantage on a street car to doing this? i know the single plane intakes have it blocked off, im running a performer rpm and could cook eggs on the darn thing...
They make an intake gasket that has an insert to block off the exhaust heat crossover. You could use a thin piece of stainless steel, but it has to be thin or it could hold your intake runners from completely sealing and the you have a vacuum leak down the road.

The disadvantage is in cold weather - hard starting and poor fuel atomization. In summer, not quite the same issue. Some will block off the heat crossover to keep heat out of the manifold so it runs cooler. It can help to some degree with fuel percolation and/or vapor lock.
 

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They make an intake gasket that has an insert to block off the exhaust heat crossover. You could use a thin piece of stainless steel, but it has to be thin or it could hold your intake runners from completely sealing and the you have a vacuum leak down the road.

The disadvantage is in cold weather - hard starting and poor fuel atomization. In summer, not quite the same issue. Some will block off the heat crossover to keep heat out of the manifold so it runs cooler. It can help to some degree with fuel percolation and/or vapor lock.
Thanks! That's what I figured.

I'm trying to build an angry squirrel motor from this 350. Here's what I'm going with:

69 xs code 350. Stock bore
69 #46 heads with 1.65 comp rockers
Edelbrock rpm
Edelbrock 750 or 70 GTO quadrajet
067 or 2802 cam.
Th400. (stock)
323 limited slip 10 bolt from a 70 gto
275/35/18 rear tires.
 

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Discussion Starter · #12 ·
Thanks! That's what I figured.

I'm trying to build an angry squirrel motor from this 350. Here's what I'm going with:

69 xs code 350. Stock bore
69 #46 heads with 1.65 comp rockers
Edelbrock rpm
Edelbrock 750 or 70 GTO quadrajet
067 or 2802 cam.
Th400. (stock)
323 limited slip 10 bolt from a 70 gto
275/35/18 rear tires.
Just make sure your pushrods don't hit the pushrod holes they pass through in the head when using the 1.65 rockers. You may have to grind for clearance. Also the 1.65's will put additional loading on the bottle neck studs and can break them off, so keep that in mind.
 

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Just make sure your pushrods don't hit the pushrod holes they pass through in the head when using the 1.65 rockers. You may have to grind for clearance. Also the 1.65's will put additional loading on the bottle neck studs and can break them off, so keep that in mind.
im having the heads gone through before the go on the car, screw in studs, porting, valve seats, elongate the pushrod holes, etc... someone on here said something in a post i read somewhere about getting 2.02 valves put into #46's. i wish i could find where i read that at.

ive decided im going with the 2801 cam... since my trans is still stock and i dont want a stall converter...

yet...

still undecided on the carb...
 

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Discussion Starter · #14 ·
im having the heads gone through before the go on the car, screw in studs, porting, valve seats, elongate the pushrod holes, etc... someone on here said something in a post i read somewhere about getting 2.02 valves put into #46's. i wish i could find where i read that at.

ive decided im going with the 2801 cam... since my trans is still stock and i dont want a stall converter...

yet...

still undecided on the carb...
That would be me.

Option #1 is Ferrea 2.11" x 4.98" X 11/32'' (0.3415'') with 30 degree seat stainless steel valves sized to the 2.02" dia - which is Chevy size. You can get a quote to have the valve diameter cut down or ask your machine shop if they can do it and at what charges.

Option #2 is the early HI-Po 283 intake valves. 2.02" x 4.911" x .3415 Stem Diameter. These can also be had in .100" longer making them 5.01".

The difference in the valves is the seat angle. Most Pontiac valves use a 30 degree seat. The Chevy valve is 45 degrees. I am not sure if you can reface the 45 degree to a 30 degree - but being new, may be possible. You would have to run this by your machinist. Prices are fairly good for the Chevy set.

 

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That would be me.

Option #1 is Ferrea 2.11" x 4.98" X 11/32'' (0.3415'') with 30 degree seat stainless steel valves sized to the 2.02" dia - which is Chevy size. You can get a quote to have the valve diameter cut down or ask your machine shop if they can do it and at what charges.

Option #2 is the early HI-Po 283 intake valves. 2.02" x 4.911" x .3415 Stem Diameter. These can also be had in .100" longer making them 5.01".

The difference in the valves is the seat angle. Most Pontiac valves use a 30 degree seat. The Chevy valve is 45 degrees. I am not sure if you can reface the 45 degree to a 30 degree - but being new, may be possible. You would have to run this by your machinist. Prices are fairly good for the Chevy set.

I got the heads out and on the workbench today. They are in way better shape than I first thought. A little crud buildup but nothing I can't handle at home with a few cans of degreaser. Two of the valves were stuck. I beat on them with a dead blow to close them and they moved but I'm just going to replace all of them. I think the motor these were on sat outside for a long time. Lots of rust scale in the champers and ports, very little wear. Probably from a wrecked car. I might just clean them, lap the new valves and put them on.
 

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