68 GTO Project

[Roadbuster]

Hey Everyone,
Been busy with my family so I haven't posted much.

With some miles and an event on the car, I can say the watts really does make a difference! It gives a very sold feel to the rear of the car. It is most noticeable when there is a bump in the turn, and instead of kicking out, it is now predicable, but i can throttle steer easily.

[jgpclone]

lookin good man

[Alain V.]

WOW! Your car is really looking good. I have an A body cutlass that will be getting pretty much the same suspension mods as you.

A question though.... with your lowered ride height, do you still have enough travel for you driveshaft without it hitting the body?
Is the angle OK???? I ask because I am considering using a ford 9inch rear to take advantage of the lower pinion snout......but I'd rather keep the use a GM rear if driveshaft clearance and angle is not an issue.
I'm planning to run a stroked 455 olds big block w/EFI and a 200R4(beefed up) trans.

Soooo nice to see you still have the Pontiac engine under the hood too. Yeah- the LS engines have alot of good points to them, but I think it takes away from the car's character when you do engine swaps.

[andrewb70]

WOW! Your car is really looking good. I have an A body cutlass that will be getting pretty much the same suspension mods as you.

A question though.... with your lowered ride height, do you still have enough travel for you driveshaft without it hitting the body?
Is the angle OK???? I ask because I am considering using a ford 9inch rear to take advantage of the lower pinion snout......but I'd rather keep the use a GM rear if driveshaft clearance and angle is not an issue.
I'm planning to run a stroked 455 olds big block w/EFI and a 200R4(beefed up) trans.

Soooo nice to see you still have the Pontiac engine under the hood too. Yeah- the LS engines have alot of good points to them, but I think it takes away from the car's character when you do engine swaps.

Usually with lowered A-bodies the issue is not with the driveshaft hitting the body. The problem is that as the cars are lowered the front and rear working angles become too great for smooth operation. So while the front and rear angle can be equalized with the use of adjustable upper rear control arms, the angle starts to get into the 4-6 degree range. Using a 9" will help some, but I don't believe it will fix the problem. I've solved the problem by having a driveshaft made that uses a Porsche 930 style CV at the front slip yoke and adjusting the rear working angle to be near zero. See my build thread for details and picture.

As for the LSx vs. old branded engines debate, there will never be a consensus because we all have individual tastes and preferences.

Andrew

[Roadbuster]

WOW! Your car is really looking good. I have an A body cutlass that will be getting pretty much the same suspension mods as you.

A question though.... with your lowered ride height, do you still have enough travel for you driveshaft without it hitting the body?
Is the angle OK???? I ask because I am considering using a ford 9inch rear to take advantage of the lower pinion snout......but I'd rather keep the use a GM rear if driveshaft clearance and angle is not an issue.
I'm planning to run a stroked 455 olds big block w/EFI and a 200R4(beefed up) trans.

Soooo nice to see you still have the Pontiac engine under the hood too. Yeah- the LS engines have alot of good points to them, but I think it takes away from the car's character when you do engine swaps.

Hey Alain,
The drive shaft does not hit the tunnel.
I have a BOP rear end in the car with the pinion down to give me the proper working angle. This is a little different than most set ups but it does work. If you look at it from the side, a line drawn through the pinion would intersect one drawn through the trans in the middle.
I have no vibration at highway speeds and did not notice any when on a short track at faster speeds. I have 3.23 gears and a TH400 trans, so no overdrive and my driveshaft has been rebuilt and balanced.

I will be looking at Andrew's very trick setup when I replace the trans with a T56 Magnum and a new set of rear gears. Those two changes will result in much higher driveshaft speeds and require a new driveshaft.

[Alain V.]

Andrew,
I just finished going through all 30 pages of your build, and found your driveshaft pics.

That is a good idea (using a CV). BMW has done this on some of their sedans for years,,,,but on the bimmer they have a fairly high failure rate. (the CV wears out on them causing terrible noise & vibration) I've seen them fail with 60k miles on them,,,and I'm pretty sure these folks don't do any drag racing with sticky tires.

I'm not saying that the CV is a bad idea to use,,,,,but I think it would probably be a good idea to put it on your list of things to periodically check when doing maintenance on your car.

I'm a mercedes tech by trade(the shop I work at specializes in german brands)

[andrewb70]

Andrew,
I just finished going through all 30 pages of your build, and found your driveshaft pics.

That is a good idea (using a CV). BMW has done this on some of their sedans for years,,,,but on the bimmer they have a fairly high failure rate. (the CV wears out on them causing terrible noise & vibration) I've seen them fail with 60k miles on them,,,and I'm pretty sure these folks don't do any drag racing with sticky tires.

I'm not saying that the CV is a bad idea to use,,,,,but I think it would probably be a good idea to put it on your list of things to periodically check when doing maintenance on your car.

I'm a mercedes tech by trade(the shop I work at specializes in german brands)

I am not expecting the CV to last forever. Even U-joints need to be replaced periodically. Honestly, if I can get 60,000 miles out of it, I would be thrilled. There is an Australian company called Holinger Engineering. They actually make a pinion yoke for the Ford 9" center section that takes a CV. It is entirely possible that at some point I may have a IRS in the GTO, at which time I am going to get a driveshaft that uses the CVs at both ends.

Andrew

[csouth]

Hey Jon, how much clearance do you have in the rear quarters with those 11" wide rears? I'm going 18x9" wide in the front, but was debating 10" or 11" width for the rear.

[Roadbuster]

Hey Jon, how much clearance do you have in the rear quarters with those 11" wide rears? I'm going 18x9" wide in the front, but was debating 10" or 11" width for the rear.

About 1/2" on each side of the tire.

[real57vetteguy]

Great build!
How do you like the SPC adjustible uppers?

[Roadbuster]

Great build!
How do you like the SPC adjustible uppers?

Great! When I had the car aligned my alignment guy spend a good 15 minutes just oogling over the suspension. It was a breeze for him to align it to SC&C's specifications. I just showed him the data sheets and how the upper arms work and he had no issues. BTW he does all the high performance alignments for the local Porsche club so he is used to modified specs.

[agto8u]

Greetings and Happy Holidays to All. FNG this is my first post.
Awesome Ride. Great Stance and tire wheel combo. Luv those seats, look like mucha mula? Keep up the great work and us updated with continued post as time permits.
You've done many of the things i'm planning on doing. I started with motor (400) and am working my way back.
T-56 w/hyd clutch coming as soon as i decide what direction to go with rearend, rebuild 3.55 non-posi BOP with Eaton posi and new axles etc.. or complete 12 bolt.

[cwmiller]

Great looking Goat Jon! Subscribed...

[455HOT/A]

AWESOME!!!!! car

[Slammd-Gto]

I saw a bright orange 68 gto with black wheels traveling north on 101 today, was that your car?

[Roadbuster]

I saw a bright orange 68 gto with black wheels traveling north on 101 today, was that your car?

Quick check in the garage, Whew! Nope not me and not my car. There must be a doppleganger running around!

[Slammd-Gto]

You know what I think it had the fixed headlights but damn it was a close match! Bright orange and black spoke wheels with polished lip, damn close but my heavy panting might have distorted the view ;)

[rohrt]

Love the build.

[93Polo]

Hey Everyone,
Been busy with my family so I haven't posted much.

With some miles and an event on the car, I can say the watts really does make a difference! It gives a very sold feel to the rear of the car. It is most noticeable when there is a bump in the turn, and instead of kicking out, it is now predicable, but i can throttle steer easily.

Awesome build, the Sparcos look great too.

Are you running poly on the axle side rear UCAs with the Watts?

[Roadbuster]

Awesome build, the Sparcos look great too.

Are you running poly on the axle side rear UCAs with the Watts?

Thanks!

Rubber on the upper mounts of the housing. It allows the compliance needed to make everything work.