Aluminum Driveline rubbing

[GT-347]

Looking for some helpful advice. I installed a Steeda 3-1/2 tapering to 4" aluminum driveline on my wife's 2007 Mustang. The car has been lowered with the Ford Racing spring kit, approx 1-1/2". Under hard acceleration in 1st and 2nd gear the driveline rubs the underside of the car (tunnel) It is NOT rubbing the emergency brake bracket, but the bottom of the tunnel.

I have installed Steeda Lower Control arms and an adjustable upr 3rd link.
The Upr link is set at Steeda suggested 8.36" dimension for performance use, Still the rubbing persists. With drag radials at the track it is even worse. The car squats a lot under hard acceleration. Anyone make rear springs that are stiffer than Ford Racing. Eiback and Steeda say their spring rates are the same as the Ford Racing springs.

I am thinking about going to a 3-1/2" driveline. Anyone know what HP a 3-1/2 can handle?

I need to figure something out, because as I said, it is my wife's car - ya know what I mean.

 

[Tylerb59]

I would look into coil overs for the rear but clearly that isn't the economical route. The compromise is having full adjustability in height and spring rate to compensate for the new weight transfer under acceleration instead of wasting time and money with coil springs.

I would totally love to have the coin to work over my suspension after getting the powertrain rebuilt.

 

[WANNA_BE_GT]

Hey Kent,

Are you saying that you replaced the 2 piece driveshaft setup with a long single driveshaft?

 

[GT-347]

I would look into coil overs for the rear but clearly that isn't the economical route. The compromise is having full adjustability in height and spring rate to compensate for the new weight transfer under acceleration instead of wasting time and money with coil springs.

I would totally love to have the coin to work over my suspension after getting the powertrain rebuilt.

I hear ya Tyler. I may go to a Fidanza 3-1/2" driveline. What a pain!

 

[GT-347]

Hey Kent,

Are you saying that you replaced the 2 piece driveshaft setup with a long single driveshaft?

Hi Corey. Yes I installed a Steeda one piece aluminum driveline in Sue's car. After adding the supercharger the rubbing is all the worse under heavy throttle.

Tuesday we are going to dyno-tweek her car at Horsepower Ranch, and Wednesday dyno-tune my 65' at Blood Enterprises (need to work out some bugs) then that evening we are going to Pacific Raceways to see which of us has the fastest Mustang. I'd love to puff up my chest and tell the little lady how things are, however, I not only have my doubts of which car is quicker, but she has turned into quite a racer. In the CCCA racing series, Sue is tied for 2nd place in points at Pacific. If that nonesense keeps up, she is going to be tough to live with.

 

[bill89saleen304]

Better watch out Kent, she just might smoke ya!! LOL

I have a Griggs Racing 3- 1/2 in. aluminum in my car, no problems with it at all.
Any reason your not having John @ HP Ranch tune the 65 as well, He is the best around, in mine and many other people's opinion!
I haven't heard much good about Blood's from quite a few people latley!



Bill

 

[05 Horseplay]

Looking for some helpful advice. I installed a Steeda 3-1/2 tapering to 4" aluminum driveline on my wife's 2007 Mustang. The car has been lowered with the Ford Racing spring kit, approx 1-1/2". Under hard acceleration in 1st and 2nd gear the driveline rubs the underside of the car (tunnel) It is NOT rubbing the emergency brake bracket, but the bottom of the tunnel.

I have installed Steeda Lower Control arms and an adjustable upr 3rd link.
The Upr link is set at Steeda suggested 8.36" dimension for performance use, Still the rubbing persists. With drag radials at the track it is even worse. The car squats a lot under hard acceleration. Anyone make rear springs that are stiffer than Ford Racing. Eiback and Steeda say their spring rates are the same as the Ford Racing springs.

I am thinking about going to a 3-1/2" driveline. Anyone know what HP a 3-1/2 can handle?

I need to figure something out, because as I said, it is my wife's car - ya know what I mean.

I also had rubbing issues with my 05 GT when I went to the one piece 4" aluminum driveline. It rubbed on the tunnel, exactly as you described.

In my instructions, they mentioned having to push up on the tunnel to create clearance......I did this, but it didn't solve the problem and it looks terrible.

In my case, the issue was in the UCA..... I installed an adjustable one and corrected the pinion angle from lowering the car. Once this was done I haven't had any further issues.

Good luck.
David

 

[GT-347]

Better watch out Kent, she just might smoke ya!! LOL

I have a Griggs Racing 3- 1/2 in. aluminum in my car, no problems with it at all.
Any reason your not having John @ HP Ranch tune the 65 as well, He is the best around, in mine and many other people's opinion!
I haven't heard much good about Blood's from quite a few people latley!

Bill

Bill, you ought to come down also. She might smoke you too. I have an extra set of drag radials that you can use - the ones that are on the classified page.

Craig Blood is a very good tuner. I also have heard people complain about him, but his tuning took my 65' from 12 -teens to 11.90's. He is a sharp guy also. I am also looking forward to meeting John at Horsepower Ranch. He sounds like a pretty knowledgable guy.

 

[GT-347]

I also had rubbing issues with my 05 GT when I went to the one piece 4" aluminum driveline. It rubbed on the tunnel, exactly as you described.

In my instructions, they mentioned having to push up on the tunnel to create clearance......I did this, but it didn't solve the problem and it looks terrible.

In my case, the issue was in the UCA..... I installed an adjustable one and corrected the pinion angle from lowering the car. Once this was done I haven't had any further issues.

Good luck.
David

David, do you know what dimension you set your UCA at? Or did you keep adjusting it until it quit rubbing? Ours is set at the recommended performance setting which is 8.36" by Steeda. I may adjust ours more, until it stops rubbing or until I begin to get some u-joint vibration.

 

[05 Horseplay]

David, do you know what dimension you set your UCA at? Or did you keep adjusting it until it quit rubbing? Ours is set at the recommended performance setting which is 8.36" by Steeda. I may adjust ours more, until it stops rubbing or until I begin to get some u-joint vibration.

To be honest, I don't remember the length, its been a while, but when I get back home next week, I'll take a measurement and send it to you. I probably did adjust it a bit more to make sure it didn't rub, but I haven't experienced any vibrations.

What LCA's are you running? Also, did you leave the factory bump stops installed when you lowered the car? I found that during hard launches my car would squat beyond where the factory bump stops were. This made the rub worse. When I put the bump stops back on, that eliminated the worst of it.

I'll shoot some measurements to you on Thursday when I get home.

Take care
David

 

[GT-347]

To be honest, I don't remember the length, its been a while, but when I get back home next week, I'll take a measurement and send it to you. I probably did adjust it a bit more to make sure it didn't rub, but I haven't experienced any vibrations.

What LCA's are you running? Also, did you leave the factory bump stops installed when you lowered the car? I found that during hard launches my car would squat beyond where the factory bump stops were. This made the rub worse. When I put the bump stops back on, that eliminated the worst of it.

I'll shoot some measurements to you on Thursday when I get home.

Take care
David

Steeda UCA & LCA. The car was lowered when we bought it from the dealer. I'll have to check to see if the bump stops are still there.

 

[TheRedBlur]

You added power, and you added diameter to the rear of your driveshaft and you're surprised about clearance issues? Granted torque arms tend to lift the chassis under acceleration, if your driveshaft has a higher diameter than is stock, it makes sense that you have rubbing issues. Either way, having something with a greater diameter means you need more energy to spin it: bad idea.

 

[GT-347]

You added power, and you added diameter to the rear of your driveshaft and you're surprised about clearance issues? Granted torque arms tend to lift the chassis under acceleration, if your driveshaft has a higher diameter than is stock, it makes sense that you have rubbing issues. Either way, having something with a greater diameter means you need more energy to spin it: bad idea.

Yes, I am surprised. I asked Steeda before purchasing it if it would rub, and told them that the car had been lowered. They said that if I changed out the upr & lwr control arms that there would NOT be an issue. They were wrong!

And FYI, it takes LESS energy to rotate an 18 lb aluminum (larger diameter) driveline, than it does to turn the stock 40 lb two piece (smaller diameter ) steel driveline.

 

[05 Horseplay]

Yes, I am surprised. I asked Steeda before purchasing it if it would rub, and told them that the car had been lowered. They said that if I changed out the upr & lwr control arms that there would NOT be an issue. They were wrong!

And FYI, it takes LESS energy to rotate an 18 lb aluminum (larger diameter) driveline, than it does to turn the stock 40 lb two piece (smaller diameter ) steel driveline.

Sorry for the delay - I just got the car in the air.

My UCA has a center to center length of 8 1/4." So not too far off from what you mentioned.

Although, once I got it in the air, I realized that I had forgot to mention one other change I have made. I did install the BMR LCA relocation brackets. But, I didn't really need to make any UCA changes when I installed them.

I'll have the car in the air for a few days, so if you want me to check anything else, please let me know and I'll be happy to do so.

Take care
David

 

[GT-347]

Sorry for the delay - I just got the car in the air.

My UCA has a center to center length of 8 1/4." So not too far off from what you mentioned.

Although, once I got it in the air, I realized that I had forgot to mention one other change I have made. I did install the BMR LCA relocation brackets. But, I didn't really need to make any UCA changes when I installed them.

I'll have the car in the air for a few days, so if you want me to check anything else, please let me know and I'll be happy to do so.

Take care
David

Thanks David. See PM.
-Kent-