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Discussion Starter #1
I have a 69 gto with a 400 but do not know what the internals are.The cam has been changed and has #62 heads with an Edelbrock rpm intake and 750 edelbrock carb.The transmission is a 200r4 rebuilt to handle 550 hp into 3.55 gears.I also have a 70/71 complete 400 block with 96 heads.The engine in the car now is # numbers correct for the vehicle so I wanted to make the spare motor into a stroker.I was looking to get 400-450 hp with iron heads.I was wondering what heads would be the best to get ported.I plan on using
1-cvms
2-butler
3- Kaufmann
I want to get the rolling assembly,porting and cam from one supplier and assemble myself.
Also should I get the intake ported to the heads.

Thanks
 

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I have to ask, why iron heads? You can put near as much $$ into some ported iron heads as you would spend on aluminum and with the aluminum you can keep your stock compression. Not to mention the weight savings, more efficient combustion chamber, screw in studs, new valves.......
 

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Discussion Starter #4
I hear ya.If i find out that aluminum heads cost roughly the same i will go that route.I was trying to go the sleeper route.I was also thinking of going back to the Quadrajet with cliff ruggles help.
 

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I have Edelbrock aluminum heads on my 474 built by Butlers, along with their rotating assembly in my '68, and this motor screams. Butlers have great customer service and are easy people to talk to. I also have a new high performance 200 4r with 373 gears, its a great set up.
 

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The problem with iron heads on a stroker is compression - too much of it.

If you want someone else to build it, I'm a big fan of CVMS. Aluminum heads can be painted (I did mine) and if you're highly motivated you can even grind off the logos.
I'm running an 800 cfm Qjet on my 461, on a single plane intake. The car so far has run a best of 11.86 at the track, and also made the whole Hot Rod Power Tour this summer.

Iron heads can be made to work, but you'll have to make compromises, spend almost as much as you would for aluminum, and won't make as much power.

I'd be willing to talk in more detail if you like.

Bear
 

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Discussion Starter #9
Thanks for all the info.
Lots of stuff to ponder.
I really don't know if my drivetrain could handle 500 plus hp.Thats why I wanted to use iron heads but should I give up the stroker idea and build a beefy 400 with aluminum heads, would that get me in the range I was looking for.
 

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Build the motor as you wanted as a stroker and if you don't put slicks on it and/or launch it at 4000 rpm the stock drivetrain should live until you can afford to upgrade it. I ran the stock 4 speed and 10 bolt behind my blown BB for a couple of years and it lived with the street tires and no powershifting.
 

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Exactly. Just because you have 500 HP doesn't mean you have to flaunt it. You can drive like a normal person and not tear your stuff up. I used to go through U-joints and trannies. Not any more. Same car, older driver!!
 

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My car before I bought it had a 428 in it. It was running a little over 450hp and was built with mostly production pontiac parts - #13 heads with a little work done to them, a RAIV cam, stock intake, quadrajet, pontiac crank, and I believe it was bored 40 over. I can talk to my friend who had it before me and get some specs for you if you want. I do know that it was a very low cost build and he was smoking people at the drag strip who had well over $10,000 and 600hp under the hood. I can't remember the 1/4 mile time but it was somewhere in the 12's before he even managed to get it tuned and dialed in.
 

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Lots of folks here with very good points. :agree

Just because you're packing the power doesn't mean you are required to be deploying it all the time. It's still very satisfying to me to be cruising along the freeway and have some moron with a new Camaro or some-such pull alongside and try to "mess" with me. When I don't take the bait, they invariably will blast on by, thinking that they've sure "showed the old dude". Meanwhile, I just smile to myself and understand that the reality of the situation was that they just weren't worth my time. :D

Now and then I do have my fun though, like a couple weekends ago at the Dallas Cars and Coffee event. Leaving, going up the on-ramp to go back home, there were a couple of late-model something-or-others all over my bumper. By the time I reached the end of the on-ramp and hit the freeway, somehow they'd gotten very tiny in my rear-view :D Imagine that...

I love discussions about how to build torque-monster Pontiacs. Truth be told, there are quite a few different ways to do it and each has its own set of merits and challenges (and costs). A big part of the enjoyment comes from planning and building an engine your way. If we all wanted to just be brainless copy-cats, we'd all be building little-block or LS ::cough spit:: chevys. :D

Speaking of my favorite brand-to-denigrate, I learned something recently. There's a guy in our local Pontiac Club who spent many years working for Pontiac at headquarters, since the 50's. He shared with us some information at the last meeting:

Did you know that Pontiac had their V8 ready to start going into cars beginning in the 1953 model year? Neither did I. Chevy threw a fit and got GM to restrain them because their engine wasn't ready - it was still having big time valve train issues. They finally talked Pontiac into letting them use the Pontiac designed stud and ball rocker system, which solved their problems in time for them to release their V8's starting in the 1955 model year. Then they actually tried to continue blocking Pontiac from releasing their V8. That idea got squashed when Pontiac said, "ok fine, but you can't use our valve train."

So, put that in your pipe and smoke it, chevy guys - the (admittedly) most wide-spread most "popular" engine ever built would have never come to pass had it not been for Pontiac. So there. :D

Bear
 

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Bear, I was aware of the rocker stud technology being borrowed by Chevrolet from Pontiac, but was unaware it was that early, or of the politics involved. Very interesting, and thanks.
 

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The problem with iron heads on a stroker is compression - too much of it.

If you want someone else to build it, I'm a big fan of CVMS. Aluminum heads can be painted (I did mine) and if you're highly motivated you can even grind off the logos.
I'm running an 800 cfm Qjet on my 461, on a single plane intake. The car so far has run a best of 11.86 at the track, and also made the whole Hot Rod Power Tour this summer.

Iron heads can be made to work, but you'll have to make compromises, spend almost as much as you would for aluminum, and won't make as much power.

I'd be willing to talk in more detail if you like.

Bear
I have a 400 in my 1970 GTO. The engine is at the machine shop ready for a rebuild. It has never been rebuilt and is in good shape. It has #62 Heads, I am running a 700R4 with 3:31 Posi gears.
My question is it necessary to go with a 461 stroker kit to get 400 hp for the street or can I just rebuild the 400 and go with a roller cam and lifters. I am running a Edelbrock Performer RPM and Holley 750. I like to drive on the freeway and since it is a convertible, I will not be at the drag strip.

Any suggestions are welcom.
 

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I have a 400 in my 1970 GTO. The engine is at the machine shop ready for a rebuild. It has never been rebuilt and is in good shape. It has #62 Heads, I am running a 700R4 with 3:31 Posi gears.
My question is it necessary to go with a 461 stroker kit to get 400 hp for the street or can I just rebuild the 400 and go with a roller cam and lifters. I am running a Edelbrock Performer RPM and Holley 750. I like to drive on the freeway and since it is a convertible, I will not be at the drag strip.

Any suggestions are welcom.
The stroker is a more guaranteed way and with more cubic inches, you can achieve more torque and HP with lower compression so you can use pump gas.

You can reach 400 HP with your engine, but you may have to do so using the higher factory compression which means higher octane race type gas or an octane additive.

You will have to go with a much larger cam to hit your goal and that will most likely move your power band up the RPM scale while sacrificing some lower end - which you may not want for a street build. RPM limits may also go up due to the cam profile, so engine internals need to match higher RPM use to fully take advantage of the cam's power range.

However, a roller cam can produce more power when matched against a flat tappet cam. If you go roller cam, then I highly suggest installing one of the available aftermarket lifter bore braces. This is inexpensive insurance that you don't bust a lifter bore with the additional side loads a roller lifter can place on them.

So you can get 400 HP out of the engine, but it will be more on the line of a race engine and require high octane gas.
 

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The stroker is a more guaranteed way and with more cubic inches, you can achieve more torque and HP with lower compression so you can use pump gas.

You can reach 400 HP with your engine, but you may have to do so using the higher factory compression which means higher octane race type gas or an octane additive.

You will have to go with a much larger cam to hit your goal and that will most likely move your power band up the RPM scale while sacrificing some lower end - which you may not want for a street build. RPM limits may also go up due to the cam profile, so engine internals need to match higher RPM use to fully take advantage of the cam's power range.

However, a roller cam can produce more power when matched against a flat tappet cam. If you go roller cam, then I highly suggest installing one of the available aftermarket lifter bore braces. This is inexpensive insurance that you don't bust a lifter bore with the additional side loads a roller lifter can place on them.

So you can get 400 HP out of the engine, but it will be more on the line of a race engine and require high octane gas.
Thanks Jim :I just found out that using my #62 heads is going to cost me about the same as Edelbrock Performer RPM heads. So I will be going with the Edelbrocks. Also the stroker kit is only going to cost a little over $1000 more than the stock kit.

So based on what I have found out and what you are telling me, this is what I plan to build :
1) Edelbrock Performer RPM Heads
2) Edelbrock Performer RPM Intake
3)Comp Cams Roller Rocker 1;65
4Comp Roller Cam and lifter #CCA-51-413
5) 462 Stroker Kit

Any suggestions ?
 

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Thanks Jim :I just found out that using my #62 heads is going to cost me about the same as Edelbrock Performer RPM heads. So I will be going with the Edelbrocks. Also the stroker kit is only going to cost a little over $1000 more than the stock kit.

So based on what I have found out and what you are telling me, this is what I plan to build :
1) Edelbrock Performer RPM Heads
2) Edelbrock Performer RPM Intake
3)Comp Cams Roller Rocker 1;65
4Comp Roller Cam and lifter #CCA-51-413
5) 462 Stroker Kit

Any suggestions ?
The stroker kit from Butler is probably the best bang for your buck. Your machinist will let you know the bore size so you can order your pistons. You'll have forged pistons and rods so no worriers with the bottom end, ie cast rods & pistons.

A good pump gas compression for iron heads is 9.0-9.3 and aluminum heads are said to go 1 point more in compression. I would shoot for 10.0. You can go higher, but from my reading, the higher the compression the bigger the LSA you want.

You will need the correct and matching head bolts for the E-head. Never used E-heads, but read they use their own head bolts.

I don't know squat about roller cams, but for a larger cubic inch engine, if it were a flat tappet, I would definitely go with more duration, 270/280 ish, and a 112 LSA. Looking at the specs, the cam is listed for 1,000 - 5,000 RPM's. With the forged bottom end and E-heads, I would want an RPM range a little higher 1,200 - 5,200. Lift with 1.65 rockers looks good.

Strongly suggest the Butler Pro 60 PSI blueprinted oil pump and a new steel oil pump shaft.

The rear main oli seal has been covered here. The 2 piece Viton can work, but the crank's seal surface should have serrations on the journal. If they are too rough, they can cut into the Viton seal and eat it up causing leaks. The serrations can be smoothed down with emery paper. However, many seem to like and have less issues, with the Best brand graphite rope seal. The rope seal actually takes advantage of the serrations as the purpose of the serrations is to draw in a microfilm of oil to keep the rope seal lubed up. The factory used a rope seal.

When installing your intake, always tighten the long top bolt at the timing cover where you will be putting the rubber O-ring timing cover-to-manifold seal. This will draw the manifold tight up against the seal. Then you torque down the intake bolts. If you don't draw the intake tight first, you may have a water leak at the O-ring.
 

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I would speak with the Butler's for a cam recommendation, but I think the one you listed would be a stump puller. It's only 212/218 at 0.050" lift.
 
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