ls1247

iTrader: (2)

Guilty as charged! But in a real world alignment scenario, I don't know what other reasonable options you have.

Verifying subframe mounting locations on the average production vehicle is pointless if you really can't do anything about it and I'm not seeing any evidence on this car (or any others really) that you have the builtin ability to align front and rear subframes with each other....

If you found the subframes weren't square with each other on a unibody car and you took it to a frame shop for "tweaking", there's a good chance the doors wouldn't open and close properly after you squared up the chassis. You could elongate the subframe mounting holes so you could move them around a bit but would the subframe stay put once you got them square with each other simply because you tightened the bolts down? I don't know...EDIT: Yes they would but elongating a bunch of subframe holes to align a frontend isn't something many consumers are willing to pay for. You'd also be responsible for anything else that this procedure may lead too.

In your experience, at what point does a SLIGHTLY "dog legging" car become a driveabilty issue?

TaylorMadeMetalWork

That's how the subframe rolls off the showroom floor, with slots to allow adjustments. As do many cars. Your said the rear cannot be adjusted which im sure is correct.. What I've been trying to say us that's where to start... the subframe. I agree on pulling the frame. I would never do that. Dog legging a drivability issue? Yea a big one if your pushing the car hard. The car is unbalanced because your chassis and suspension are headed a different way then the wheels. The car will turn one way much better then usual and turn the other way terribly usually because the front or rear gets really light and lose grip.

ls1247

iTrader: (2)

I haven't loosened the front subframe bolts to see if the subframe is slotted but it would be nice! I would imagine some of us could benefit by some sort of "squaring" process so while my 05 is still on stands, I'll be looking into that!

I didn't know if you guys might have some sort of tolerance for the "dog legging" of the cars you're building. Would an 1/8" be noticed given all the rest of the flex found in a car being pushed to the limit?

TaylorMadeMetalWork

As far as tolerance I wouldn't say it's a single answer. In what I do an 1/8" out on any alignment angle is HUGE. That would go for most professional motor sport. Your shooting for no more then half of that , so 1/16". In a street car with hard tires and soft suspension it might not be as noticeable... however a good race car driver (not someone who drag races) in a fast car could usually tell you the car turns much better left then right. They don't have a clue why... but that's where the crew comes into play.

ls1247

iTrader: (2)

So I get my 05 back together and take it out for a clutch dump and not suprisingly, the wheel hop is gone with the connectors but the driveline vibes are back. Come to find out, I gained about 1/4inch of height on the connectors when we welded them together and they are so stiff, they pushed the front of the cradle up when I tightened them down and it screwed up my pinion angle. Its always something.

So when I get them back in the car, I'll have to get them shimmed PERFECTLY to maintain my pinion angle....WAPITA.

I also posted up in the flex disc post about how crooked my 2 piece driveshaft is in my 04 which kinda ties in to the conversation we were having above about aligning the cradles....

https://ls1tech.com/forums/cadillac-...acement-2.html