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Looking for inspiration for my 67. Numbers matching 400, bone stock minus an edelbrock carb and an electric choke. Currently has a flowmaster exhaust. Manual swapping, so hit me with transmissions you like too.

What's your dream build? Tri-Power? Efi? Let's see it.

Frame is also stock, so let's not get too crazy with the torque.

If it requires boring out the block, bonus points if you can get me a name of somebody in LA that can do it.
 

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Looking for inspiration for my 67. Numbers matching 400, bone stock minus an edelbrock carb and an electric choke. Currently has a flowmaster exhaust. Manual swapping, so hit me with transmissions you like too.

What's your dream build? Tri-Power? Efi? Let's see it.

Frame is also stock, so let's not get too crazy with the torque.

If it requires boring out the block, bonus points if you can get me a name of somebody in LA that can do it.
(1) For me, a good Muncie 4-speed is the ONLY way to go. The gear ratio you'll need for trans & rear end will depend on the stroke & low rpm torque of your engine build.

https://midwestmuncie.com/

(2) I'm a Q-jet guy, all the way ! Since your engine is numbers matching, just seems to NEED a correctly rebuilt Q-jet.

(3) I like 455 or more cubes, because of the extra low rpm torque. But, if your crank is good, a correctly built 3.75 stroke engine can produce plenty of tire smokin power.

(4) Factory 670 heads provide too much compression for today's pump gas. So, if you keep 'em, you'll need to use dish pistons, to reduce the CR.

(5) Unless you want a really lumpy idle, an 068 clone, or a Summit 2801 will be plenty of cam. But, there are others that will make more power and produce a different idle sound.

(6) If by "LA" you mean the state of Louisiana, I can help you with an engine builder. If you mean Los Angeles, probably not. You might contact Leo Glasbrenner, at his transmission shop, REMAC Transmissions. He is a long time Pontiac drag racer. He can probably help you find a machine shop.

https://www.google.com/search?q=remac+transmissions&rlz=1CAHKDC_enUS777US777&oq=remac+trans&aqs=chrome.2.35i39j69i57j0l4.9350j0j4&sourceid=chrome&ie=UTF-8

John & Ryan Schloe also race Pontiacs. They can probably help you.

https://www.facebook.com/john.schloe.1

https://www.facebook.com/Schloe-Machine-Products-Inc-124942522342/?eid=ARDzU_v_0qBE0-h7UqDQXUe_UB1qfQYA9bP5OVpL4w6IZNk3EJeSqUEMVgFAh_NIMFPWFm5J951qiRm4&timeline_context_item_type=intro_card_work&timeline_context_item_source=100016071517243&fref=tag

MANY who have numbers matching engines, store that engine, for future sale with car, then build the engine they want. Here are a 455 & a 400 crate engine, just to give you an idea.

http://lenwilliamsautomachine.com/455_Long_Block.html

http://lenwilliamsautomachine.com/400_Long_Block.html

There are LOTS of Pontiac engine options, such as forged rods & pistons, alum heads, roller cams & rockers, alum intakes, etc.
 

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Rather vague question and does not really inform us of what you are looking to do.

Numbers matching, I get it. But how much modification are you willing to do? Stroker assembly, aluminum heads, roller cam/lifters, forged pistons/rods if keeping stock stroke, points or electronic ignition.

What RPM range do you want to see the best performance, lower, mid, or upper? Torque or horsepower?

Gear ratio you plan to run in the rear? Posi or non? stock 10-bolt, Chevy 12-bolt, or going to a Ford 9"?

Stock tires or wide sticky meats that'll lunch the factory 10-bolt, rip the rear-end out, and possibly the rear control arms?

What is your intention for the car? Stock/display, some hard driving, street/strip, or more strip?

Are you OK spending 5K-15K on the engine, plus another 5K-8K on the driveline?
 

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Discussion Starter #4
Rather vague question and does not really inform us of what you are looking to do.

Numbers matching, I get it. But how much modification are you willing to do? Stroker assembly, aluminum heads, roller cam/lifters, forged pistons/rods if keeping stock stroke, points or electronic ignition.

What RPM range do you want to see the best performance, lower, mid, or upper? Torque or horsepower?

Gear ratio you plan to run in the rear? Posi or non? stock 10-bolt, Chevy 12-bolt, or going to a Ford 9"?

Stock tires or wide sticky meats that'll lunch the factory 10-bolt, rip the rear-end out, and possibly the rear control arms?

What is your intention for the car? Stock/display, some hard driving, street/strip, or more strip?

Are you OK spending 5K-15K on the engine, plus another 5K-8K on the driveline?
I kind of left it open ended because I wanted to see some different setups for different ideas.

As far as what I want, I want it to have some modern Reliability at the 7-800hp mark at lower rpm, mostly for the street and maybe shows once I finish the body work. Beyond that, I’m very open to the rest, hence the “I want to see how you would build your dream GTO” topic. I have no real upper limit on mods as long as I keep the same block and I can keep a stock-looking exterior. I have budgeted properly for the engine and driveline and could pretty easily meet those numbers you threw out.
 

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I kind of left it open ended because I wanted to see some different setups for different ideas.

As far as what I want, I want it to have some modern Reliability at the 7-800hp mark at lower rpm, mostly for the street and maybe shows once I finish the body work. Beyond that, I’m very open to the rest, hence the “I want to see how you would build your dream GTO” topic. I have no real upper limit on mods as long as I keep the same block and I can keep a stock-looking exterior. I have budgeted properly for the engine and driveline and could pretty easily meet those numbers you threw out.
Must be your first Pontiac?

You won't get 7-800HP out of a stock Pontiac block - it will not live, nor was it ever designed to reach this level.........they break - typically split.

If you want to reach your goal, then an aftermarket Pontiac block is what you want to begin with. There is the IAII from Butler Pontiac or the MR-1 from Kauffman Pontiac.

If you want to keep the stock block, then you might reach 600 HP. Here is a member's recent 600 HP build and his specs: https://www.gtoforum.com/f170/just-dyno-d-my-engine-134833/

In matching the above HP/TQ numbers, 4-speed trans choice would be an aftermarket/new M-22 with its improved upgrades. https://midwestmuncie.com/

The TKO 600 5-speed or the 6-speed will handle big HP if you want overdrive for highway cruising, but you will have to cut/modify your transmission tunnel for fit. Have it worked by American Powertrain. They also have complete kits for installation: https://americanpowertrain.com/body_type/gm-a-body/?swoof=1&manufacturer=gm&really_curr_tax=2671-body_type

For a rear end, I would not use anything less than a well built aftermarket Ford 9" from one of the many big name suppliers set up for the A-body mounts.

You will need to beef up the frame by boxing the rails going 7-800HP, as well as installing upper & lower control arm braces to tie them together. You may want to plate and strengthen the lower control arm mounts at the frame. I did this on my car. They are not too hefty if you have a lot of HP.
 

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700-800hp naturally aspirated ur gonna need a lot of cubes, a lot of head and a ton of cam. Go smaller in any of those areas and ur gonna need a lot of compression to make up for it. All of which making it hard to be a “street car”. Shoot for 650hp or so at the crank and keep it 10:1 so you can run it on 93octane. Gonna need a stroker kit. Butler has a budget friendly 461 Eagle stroker kit fully forged that uses a standard big block chevy rod size for a little over $2k for a 400 block. Just pulled one out of the machine shop with that same combo for a customer. For the heads talk to Kaufman racing. They have the KRE D-ports that outflow the edelbrock castings offered by butler out of the box and they offer 3 levels of porting on top of that. Have a custom cam ground by kre or someone like Ed Curtis from flow tech induction for max power and drivability. Butler tends to spec with off the shelf comp grinds. Go with a Northwinds single plane intake for the hp numbers you’re looking at. You’ll need a big carb or something like a Holley Sniper efi. I’m more new school than most on here and love the benefits, drivability and tune-ability of the new EFI style setups with timing control, especially the throttle body injection style that looks like a carb sitting on top of the motor. The Super Sniper will take care of you up to around 700hp naturally aspirated. The regular sniper will go up to 650hp n/a.

Or..... go with a low compression 400 build and boost it to the moon!
 

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Yeah, 700+ hp on pump gas, will require an aftermarket block, and big cubes. This engine will also have 700+ torque, which, as mentioned, will require beefing up everything else.

Here's a few sources for big power Pontiac engines.

Kauffman Racing Equipment

https://www.sandovalperformance.com/engines

https://butlerperformance.com/c-1267471-engines-blocks-engine-kits-butler-crate-engines-complete.html

https://www.facebook.com/PaulKnippensMuscleMotors/

https://www.dcimotorsports.com/services/dci-ram-air-five-crate-engine/

http://www.spottsperformance.com/IA2 engine block2

https://www.google.com/search?q=koerner+racing+engines&rlz=1CAHKDC_enUS777US777&oq=koerner+racing+engines&aqs=chrome..69i57j69i65.10462j0j4&sourceid=chrome&ie=UTF-8

My engine guy built a 400 block stroker that made 755hp. But, it ran E-85. Had KRE High Port heads, Northwind intake, 1050 Dominator carb, solid roller cam. Built it for dirt track racing. Made 755hp @ 5900 rpm. Ran strong, in several races. No failures. He also built a similar back-up engine. Later put it into a '69 GTO street car. Drove it to a show I attended.

He made quite a few mods to the stock block, to make it live. Better to use an aftermarket block. You can even buy an alum block, and save some front end weight.
 

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If you are from Los Angeles you're stuck with 91 octane and unless you're planning to add octane booster to every tank you may need to dial down that HP figure. Not saying it can't be done, but with 91 your options for a street car running pump gas become fewer.

I'm bringing my original owner, numbers matching 68 back to life after 25+ years. Since this will be a cruiser I'm building the engine with only a mild power increase and the ability to operate on 91 without detonation. That means low compression and a forged rotating assembly.

IMHO do get another block and put the original away with the auto trans. With the HP figure you're shooting for its not worth the risk of a catastrophic failure destroying your original.

Remember, they're only original once.
 

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Discussion Starter #9
If you are from Los Angeles you're stuck with 91 octane and unless you're planning to add octane booster to every tank you may need to dial down that HP figure. Not saying it can't be done, but with 91 your options for a street car running pump gas become fewer.

I'm bringing my original owner, numbers matching 68 back to life after 25+ years. Since this will be a cruiser I'm building the engine with only a mild power increase and the ability to operate on 91 without detonation. That means low compression and a forged rotating assembly.

IMHO do get another block and put the original away with the auto trans. With the HP figure you're shooting for its not worth the risk of a catastrophic failure destroying your original.

Remember, they're only original once.
Good points all around in the thread so far. I've decided the horsepower should be saved for another build. I'm just going to look for something more 3-450 range with the original block- but I am keen on swapping the his/hers out for a manual. Even with the 91 we have here, that should be pretty easily obtainable.

My last big thing here will be looking for quality paint and bodywork.
 

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Must be your first Pontiac?

You won't get 7-800HP out of a stock Pontiac block - it will not live, nor was it ever designed to reach this level.........they break - typically split.

If you want to reach your goal, then an aftermarket Pontiac block is what you want to begin with. There is the IAII from Butler Pontiac or the MR-1 from Kauffman Pontiac.

If you want to keep the stock block, then you might reach 600 HP. Here is a member's recent 600 HP build and his specs: https://www.gtoforum.com/f170/just-dyno-d-my-engine-134833/

In matching the above HP/TQ numbers, 4-speed trans choice would be an aftermarket/new M-22 with its improved upgrades. https://midwestmuncie.com/

The TKO 600 5-speed or the 6-speed will handle big HP if you want overdrive for highway cruising, but you will have to cut/modify your transmission tunnel for fit. Have it worked by American Powertrain. They also have complete kits for installation: https://americanpowertrain.com/body_type/gm-a-body/?swoof=1&manufacturer=gm&really_curr_tax=2671-body_type

For a rear end, I would not use anything less than a well built aftermarket Ford 9" from one of the many big name suppliers set up for the A-body mounts.

You will need to beef up the frame by boxing the rails going 7-800HP, as well as installing upper & lower control arm braces to tie them together. You may want to plate and strengthen the lower control arm mounts at the frame. I did this on my car. They are not too hefty if you have a lot of HP.
Not only my first pontiac but my first classic at all, so I'm very new to it all. I'm going to save the horsepower for a later build and cut that 7-8 number in half. I'm going to take your advice on the ford rear end though. Not sure I will need to box the frame with the new 3-450 hp number.
 

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Not only my first pontiac but my first classic at all, so I'm very new to it all. I'm going to save the horsepower for a later build and cut that 7-8 number in half. I'm going to take your advice on the ford rear end though. Not sure I will need to box the frame with the new 3-450 hp number.
Agreed, boxing not needed at lower levels. This is really a safer route to take and will be more streetable. Even at that level, you'll be tearing up tires. Remember, build for a good torque engine and accept whatever the HP is that goes with it. Hitting 500-525 Ft Lbs of torque is not too hard. More as you go with aftermarket heads and/or roller cams.

Your cam is one of the most important selections. It puts the HP/Torque numbers where you want to see them on the RPM range. No 1 cam will do it all, so you have to decide where you want your power range to be. This takes into consideration your trans/gear choice. You don't want a real torque monster down low if you have the lower trans gear ratio's that are often found in the 5/6-speeds. You will simply smoke tires until you get rolling. So moving the HP/Torque range up a little takes advantage of the gearing as well as the engine's performance.

Next is head selection. You don't want to build a big stroker engine only to have it limited in RPM by the CFM flow of the heads - unless you plan for that. Cam selection is also tied into head flow. You don't need a big lift, long duration cam if the heads won't flow. You would only be throwing away money and performance and be disappointed.

So you want to sit down and come up with a build plan that matches all components for your best performance - engine and its components, along with your driveline selection.

Do add the upper & lower control arm braces to tie them together and provide a lot more strength out back. I went with the UMI brand, but there are others. 1964-1967 GM A-Body Control Arm Reinforcements/Frame Braces [4029] - $149.99 : UMI Performance, Inc.
 
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