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Cameo Ivory 1967
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5,311 Posts
Discussion Starter · #1 ·
Okay, we've been yapping about this, so here's the beginning. My intention is to end this thread as with my others in the FAQ section, where I will continually come back and re-edit this initial post, so that when it's all done, it'll be a comprehensive, step by step, build.

I know barely anything about this, so it's going to be a work in progress, and a 100% collaboration, relying heavily on the old-skool guys tips/ tricks/ and advice, as well as everyone else scouting for facts, parts, and modern tech.

Moving on!

One of my good buddies, @1969GPSJ has a 68 400, and he's within driving distance, so my goal is to get out to him and pick it up, ASAP.

In the mean time, I traded a seized 327 CHevy, for another 68 400 short block, and @PontiacJim believes it to be an original engine, with no rebuild history, so hopefully it's a good core!

Hunting for machinists, I hit Google and called shop number one, out of the blue. Guy answers, and long story short, him and his mother owned the speed shop that I built my first car, a 67 Nova at! Then when I traded that for my 66 Lemans, they got me all my parts! So!!! I have an experienced, trustworthy machinist, 30 minutes away.

I'll drop the block off to them and they will charge me $150 to remove all of the bearings and plugs, blast/ bake the block, and magnaflux it. While that's being done, I'll head out to MD to get the 2nd 400, and I'll try to do them both at the same time.

We need to now find some heads! I can get 670's, but their from unverified, strangers on the web, and expensive! So... nope.

Wood Font Auto part Engineering Metal
 

· Registered
66 GTO post coupe
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406 Posts
Okay, we've been yapping about this, so here's the beginning. My intention is to end this thread as with my others in the FAQ section, where I will continually come back and re-edit this initial post, so that when it's all done, it'll be a comprehensive, step by step, build.

I know barely anything about this, so it's going to be a work in progress, and a 100% collaboration, relying heavily on the old-skool guys tips/ tricks/ and advice, as well as everyone else scouting for facts, parts, and modern tech.

Moving on!

One of my good buddies, @1969GPSJ has a 68 400, and he's within driving distance, so my goal is to get out to him and pick it up, ASAP.

In the mean time, I traded a seized 327 CHevy, for another 68 400 short block, and @PontiacJim believes it to be an original engine, with no rebuild history, so hopefully it's a good core!

Hunting for machinists, I hit Google and called shop number one, out of the blue. Guy answers, and long story short, him and his mother owned the speed shop that I built my first car, a 67 Nova at! Then when I traded that for my 66 Lemans, they got me all my parts! So!!! I have an experienced, trustworthy machinist, 30 minutes away.

I'll drop the block off to them and they will charge me $150 to remove all of the bearings and plugs, blast/ bake the block, and magnaflux it. While that's being done, I'll head out to MD to get the 2nd 400, and I'll try to do them both at the same time.

We need to now find some heads! I can get 670's, but their from unverified, strangers on the web, and expensive! So... nope.

View attachment 161222
I’ll be taking notes !!
 

· Premium Member
1964 GTO, Tri-power, 4 speed, manual brakes & steering, black ext. red int., dog dish caps, T.I. ign
Joined
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86 Posts
Army does your initial 400 from buddy have heads? What head number(s) are you choosing to seek? I see that 670 (from the Wallace head search feature) are 1967 400 heads. What compression and year are you seeking 1968?
 

· Premium Member
Joined
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3,209 Posts
Okay, we've been yapping about this, so here's the beginning. My intention is to end this thread as with my others in the FAQ section, where I will continually come back and re-edit this initial post, so that when it's all done, it'll be a comprehensive, step by step, build.

I know barely anything about this, so it's going to be a work in progress, and a 100% collaboration, relying heavily on the old-skool guys tips/ tricks/ and advice, as well as everyone else scouting for facts, parts, and modern tech.

Moving on!

One of my good buddies, @1969GPSJ has a 68 400, and he's within driving distance, so my goal is to get out to him and pick it up, ASAP.

In the mean time, I traded a seized 327 CHevy, for another 68 400 short block, and @PontiacJim believes it to be an original engine, with no rebuild history, so hopefully it's a good core!

Hunting for machinists, I hit Google and called shop number one, out of the blue. Guy answers, and long story short, him and his mother owned the speed shop that I built my first car, a 67 Nova at! Then when I traded that for my 66 Lemans, they got me all my parts! So!!! I have an experienced, trustworthy machinist, 30 minutes away.

I'll drop the block off to them and they will charge me $150 to remove all of the bearings and plugs, blast/ bake the block, and magnaflux it. While that's being done, I'll head out to MD to get the 2nd 400, and I'll try to do them both at the same time.

We need to now find some heads! I can get 670's, but their from unverified, strangers on the web, and expensive! So... nope.

View attachment 161222
Nice ! And will all pitch in for a sign for your new garage or are you still going to do all this outside in 20 degrees on the gravel driveway :D How about... Amy's Pontiac Motor Shop ;)
 

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Cameo Ivory 1967
Joined
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5,311 Posts
Discussion Starter · #7 ·
Army does your initial 400 from buddy have heads? What head number(s) are you choosing to seek? I see that 670 (from the Wallace head search feature) are 1967 400 heads. What compression and year are you seeking 1968?
No heads on either motor.

Yes, 670's at one-year-only, 1967, closed chamber heads. I've been running them in Jersey sense 1992, without issue... and they're the only heads that I know anything about... so Im open to suggestions.

Right now, I suppose Im pushing 10 to 1 on my car... but I know everyone recommends getting that lower.
 

· Premium Member
1964 GTO, Tri-power, 4 speed, manual brakes & steering, black ext. red int., dog dish caps, T.I. ign
Joined
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86 Posts
My 428 is at the machine shop. Machinist says to stay with cast iron heads use 9 to 1 compression ratio. I pushed it just a bit to 9.25 to 1. The #12 RA III heads cc'ed at 75 cc's. The book says 72 cc's. With advice from this forum, I cc'ed the heads not taking the factory specs as gospel. I also thought of going to Edelbrock heads (aluminum) knowing I could bump up the compression another 1 point. The #12's have already been paid for, worked on and it would be wasted money. I will be just fine. Pistons ordered from RaceTech. I have heard PJim endorse AutoTech, same company.
 

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547 Posts
Have fun with your build , try to keep the squish tight and good luck

as a side note I took my 16’s to a good shop in KC for a look over and while talking I asked if anyone ports cast anymore…….he chuckled and said good luck

Looks like the aluminum trend continues
butler did do cast iron you may check with them. but aluminum may be more reasonable.nitemare performance may also still do that.
 

· Premium Member
Joined
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3,209 Posts
Okay, we've been yapping about this, so here's the beginning. My intention is to end this thread as with my others in the FAQ section, where I will continually come back and re-edit this initial post, so that when it's all done, it'll be a comprehensive, step by step, build.

I know barely anything about this, so it's going to be a work in progress, and a 100% collaboration, relying heavily on the old-skool guys tips/ tricks/ and advice, as well as everyone else scouting for facts, parts, and modern tech.

Moving on!

One of my good buddies, @1969GPSJ has a 68 400, and he's within driving distance, so my goal is to get out to him and pick it up, ASAP.

In the mean time, I traded a seized 327 CHevy, for another 68 400 short block, and @PontiacJim believes it to be an original engine, with no rebuild history, so hopefully it's a good core!

Hunting for machinists, I hit Google and called shop number one, out of the blue. Guy answers, and long story short, him and his mother owned the speed shop that I built my first car, a 67 Nova at! Then when I traded that for my 66 Lemans, they got me all my parts! So!!! I have an experienced, trustworthy machinist, 30 minutes away.

I'll drop the block off to them and they will charge me $150 to remove all of the bearings and plugs, blast/ bake the block, and magnaflux it. While that's being done, I'll head out to MD to get the 2nd 400, and I'll try to do them both at the same time.

We need to now find some heads! I can get 670's, but their from unverified, strangers on the web, and expensive! So... nope.

View attachment 161222
Nice ! And will all pitch in for a sign for your new garage or are you still going to do all this outside in 20 degrees on the gravel driveway :D How about... Amy's Pontiac Motor Shop ;)
Been doin it that way since 87, so yes!
Ok better you than me but I think if you tried it you would like it ;) So these motors have to be stock appearing no aluminum heads?? You you can have aluminum painted for that stealth look...some KRE's would be real nice;)
 

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Cameo Ivory 1967
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5,311 Posts
Discussion Starter · #15 ·
The thread will be aimed at the following:

Can the average, handy, GTO owner, build a Pontiac engine, at home, and have it be dependable? And if so, can additional attention to detail, get you close to one HP per cubic inch?

That's what I hear most users trying to find.

As for what goes on the engine, obviously, I was proceeding under the assumption that most of us were working with "paper-route" bucks, but if you're offering to dress up as Daddy Warbucks, then aluminum heads and a balanced Eagle rotating assembly it is!

However, IME, anyone with $6000 for aluminum heads and a forged, balanced rotating assembly, probably isnt going to build an engine in their driveway.

Suffice it to say that anyone who chooses to follow along, will be able to substitute whatever they want, with whatever they want.

I would LOVE to use aluminum heads, but aside from saving weight, for the same money, I can do iron heads, making the same HP, and have enough money left over for a cam, lifters, intake, carb, timing chain, and water pump... maybe even manifolds!
 

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My 428 is at the machine shop. Machinist says to stay with cast iron heads use 9 to 1 compression ratio. I pushed it just a bit to 9.25 to 1. The #12 RA III heads cc'ed at 75 cc's. The book says 72 cc's. With advice from this forum, I cc'ed the heads not taking the factory specs as gospel. I also thought of going to Edelbrock heads (aluminum) knowing I could bump up the compression another 1 point. The #12's have already been paid for, worked on and it would be wasted money. I will be just fine. Pistons ordered from RaceTech. I have heard PJim endorse AutoTech, same company.
I ran #12's on my '67 400 and they pinged like hell on 93 octane pure gas that was available then (1980's).
I would never consider running them now unless I built an engine with 15-20cc dished pistons.
If you run #12's you should run 100 octane fuel to keep the engine alive.
 
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