OK, a double whammy-

First, any thoughts on steel vs. aluminum driveshafts?

Second, I'm using the guide posted by Inland Empire Driveline as a referance for setting up my driveline angles. IED wants the centerlines for the transmission output shaft and pinion shaft to be parallel. However, the transmission points toward the ground at 4 deg. and the pinion points at the ground at 2 deg. at ride height. This causes a 6 deg difference. To make up 6 deg. will require some serious machining to my lowering blocks. I have Guldstrand slolom springs in the car. Is this a common occurance on aftermarket springs or did GM run non-parallel centerlines?

Any thouhts will be appreciated.

Thanks. Carl


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To see a picture of my car http://www.geocities.com/casanoc

Carl,
I've been looking at aluminum driveshafts for some time. A couple of my concerns are.
1. the driveshafts are usually larger diamiter than stock, there might be clearance problems.

2. The driveshaft tube might hold, but the yoke ends are probably very highly stressed. The next weakest area is probably where the yoke joins the tube.

3. I KNOW a steel driveshaft will work without any problems.

I'm shure an aluminum driveshaft would work on a stock Camaro. And probably on a 400 hp Camaro. But, what is the upper limit? I'm hoping for a 500+hp engine for my Camaro. And I'm not shure if I want to find out the hard way.

On the pinion angle. I'd shoot for 2 to 4 degrees difference static.
When you accelerate hard the pinion will rotate up a couple of degrees with a leaf spring suspension. You might try a 3/8" spacer under the rear trans mount. It will reduce the angle. 1 to 2 degrees. There are tapered diff shims available for the rear.
David

david-

We're on the same page. In talking with IED, they stated that a 3 1/2" 1350 series u-joint aluminum shaft would be the way to go. Stock is 2 1/2" 1310 (TH350). The end-yokes are beefier than the 1350 size steel units. Ford Motorsport sells a 3 1/2" Al driveshaft for the 5.0. It has 1330 (TH400 size) u-joints. Torker has a friend with a 5.0 and this shaft that runs high 10's. GM Performance Parts also sells one for the LT1 and LS1 Camaros. Steilow is running one on the Thrasher and IED builds them for Warren Johnston. But, I still wonder about long-term metal fatigue. I have not seen a high-HP street car that used regularly that runs an Al driveshaft. Plus, steel is much less expensive. Is spending an extra $150 worth the 7 lb rotational mass advantage and the worry?

Unfortunately, the trans spacer won't fit. I'm putting in a Tremec and have already shoved the trans up into the tunnel as far as it will go so it's gotta happen at the spring perch. I'm going to machine the lowering blocks since I don't like the idea of having so many things bolted in there. I don't even like the lowering blocks but I'm waiting to see what the spring sag will look like after 1 year of use. If I went for the 2-4 static angle, is there enough torque applied at cruise to straightnen things out and minimize driveline vibrations, or am I just splitting hairs?

Thanks David

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To see a picture of my car http://www.geocities.com/casanoc

Carl, if you are worried, screw the theoretical advantages of the aluminum. Steel will give you the piece of mind you want. THAT is more important.

If you buy aluminum, are you going to be worried the driveshaft is going to break every time you punch the gas? With as much research on driveshafts as I know you have done, it is clear you still haven't resolved this issue in your mind. Go steel.

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Hugger Orange & white 69 Camaro with supercharged 350, Tremec TKO, and 3.73 12-bolt

See my website updated 4/5/00 at:

www.geocities.com/gheatly (http://www.geocities.com/gheatly)

I concur... Often times Aluminum is desirable, but in this case I think not. Unless you are in a weight contest with an Audi A8, forget aluminum and go the bullet proof route, especially in a critical link such as this.

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Shawn Peterson
1969 Z28, 406SB
http://www.geocities.com/corsican69

Inland Empire Driveline - are they in San Bernardino? If they are the ones I am thinking of they are the old MOB racing crowd. They did a driveline for me way back in the 80's on a 350 dropped into a Datsun pickup. Great sleeper, PG trans, 5.38 rear gears.

i have an aluminum driveshaft in my 79 TA, love it, less vibrations. It is fatter, but fits with no problem. i hear they really can't handle more than 800 hp, (don't fret: i'm covered there)

i needed a custom one anyway, costed me 300 to have done.

it is supposed to help top end speeds amd mph, how true that is i have no idea, i bought it for less vibrations

Done. 3" steel with 1350 Spicer no-zerk HD u-joints. $259 out the door ready to slip into the car. Hopefully by Friday I will be able to comment on how the subframe connectors and the Tremec TKO work.

Thanks guys.

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To see a picture of my car http://www.geocities.com/casanoc

Carl,
I'd go for the 2 degrees static. Four is getting up there and may cause vibrations. There is a trick done to get more anti squat on Camaros. You can drill a hole higher on the front spring mount, the one that goes thru the front spring eye. I'm not shure how much higher you can go on a stock spring. If you go too high the spring eye will hit the bracket. Check it out, perhaps redrilling the bracket will change the angle enough. Another benefit is greater anti squat.
David

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The older I get, the faster I was!

I did some added research on the spring mounts. You can only do it if you have smaller than stock spring eyes like the Guldstrand springs. Otherwise the spring eye will hit the mount.
David

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The older I get, the faster I was!

Thanks David, I'll check out the mount since I run the Guldstrand spring but not the racing spring. I may be out of luck on that. However, I did get to drive the car with 3 deg. static and so far so good. I need to remachine the lowering blocks to slightly raise the ride height and when I do I will go for 2 deg.

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Click here to see see my car and hear 5-speeds. http://www.geocities.com/casanoc

A properly done Aluminum d/s is more than strong enough remember they take different u-joints because of the dissimlar metals the caps are coated.I would stay away from hd u-joints because you have to take them apart to grease them you can have a 10 sec. car and still use regular u-joints for that matter alot of guys still ran the stock d/s.

ever consider carbon fiber drive shafts? i have heard about them but never saw one. don't know what they would ask for. but talk about light and strong... http://www.camaros.net/forum/biggrin.gif

JS

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