The Dodge Challenger Message Board

hey anyone have an opinion on al vs steel........ive talked to eddie about this...just wondered if any one has any hipo experience with the two types........rotating mass really concerns me....and ive heard great increase in torque and hp with alum.......jsut wonder about tuffness.....anyone out have any stories....i would love to hear them.....thanks

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i dont want to start any controversy,but..my experience is this , i had a new aluminum drive shaft made, in hopes to get a little more power, but get this when i got home i got the scale out and there was only a few grams difference in weight,due to the fact alot more aluminum has to be used to make it strong,especially in the ends,so if weight is what your after it wont help,it didnt really make a difference in power either, if i had to do it all over again i would stay with steel, i also spent about 350.00 usd, so you might rethink that, i will say this alot of modern cars and trucks have aluminum drive shafts for different reasons, but with a v8 engine putting out at least 300 hp, they have to make aluminum thicker resulting in about the same dimension and weight,but thats just me

I don't know the difference between a new steel and aluminum driveshaft, but when I got my new aluminum one delivered, I practically had to open the box to make sure the DS was inside. Very light.
Custom made 3.5" aluminum from inland empire driveline ( http://www.iedls.com ).
Got it in a transmission kit from Classic Mopar 5-speed.

I weighed it, but, being an idiot, I forgot to write the weight down, and I don't remember anymore.

Compared to the original driveshaft, it is probably around half the weight.

I remember Mopar Action (I think?) fitted one to their RoadRunner project and sung its praises.

I have seen both kinds of driveshaft twisted into a knot at the Drags. Big torque does not seem to care what material they are made from.

THANKS guys........ive had mine out severalr times and honestly never really considered it real heay...nothing that really shocked me......but i need a new one now.....and i have serveral options.....a local shop can make me one real quick...from anywhere from 150 to 350...depending how thick i want it???....guess they would look at my stock one now i guess?.....or eddie hooked me up with dennysdrivshaft......350 to 600 from hd shafts guaranteed not to twist or break....or nitrous approved steal ones and there aluminum shaft that are not guanteed.......and there 3's.... 3.5's and even 4 inchers.......so thats why im asking.....wonder if mopar from the factory beefed up the shafts from car to car....like say a 383 vs a 440 six pack or,,,,, a hemi shaft vs a 440 shaft......

If you do get one locally Jeff, make sure it's made from drawn over mandrel steel tubing,(D.O.M.), it's way stronger than plain pipe steel tubing and many drivehshaft shops use the cheaper grade because it's easier to work with and they make a higher profit from it. Also make sure they use a high speed balancer thats capable of spinning higher than 3000 RPM's which a lot of the older truck based shops use. Diesel's dont turn a lot of speed so some of the shops use truck based equipment. Just some things to ask the shop if they construct your's locally. Fabians suggestion, Island Empire is great, so is Denny's both have adone a lot of work for the NHRA/IHRA racers and they know what they are doing! This is one area I would try and get the strongest/highest quality components you can afford. You were very lucky that day! A lot of cars have almost been totally destroyed from such failures because at speed, you may lose control and crash into something. You're engine is a beast!LOL

eddie ur the man.......i appreciate it.....my heads getting to big...u keep telling me what a beast that thing is!!!!! .....im starting to believe ya!
well i called denny;s....i called the tech line and i got some girl.....she put me on hold for 8 minutes....so i hung up.....i emailed them instead and im awaiting there reply....hopefully there product isbetter than there service...lol........any im waiting.....just wonder what the threshold is on the aluminum shafts....ya know....hp wize......vs goin with a 3 or 3.5 steel one thats guaranteed.....and what the steel ones weigh compared to stock........mine never felt heavy....but maybe thats why it twisted????......my car is a 318 car so maybe thats the factory shaft?....i dont know....

Actually Jeff, it's the torque that does the damage, it always is. I dont think the alloy,(alluminum), shaft will be harmed either, but the Chrome-Moly steel is the strongest. Thats why they dont have a guarantee on the alloy. Racers are totally obsessed with weight. or the lack therof. For good reason, less weight on the vehicle, less stress on the driveline components,, plus better reaction time from less rotating inertia and mass. But if you are contemplating 'squeeze' then I would opt for the steel shaft and 1350 yokes with U-joint style straps which are standard equipment on the 1330/1310/1350 u-joint series I think or at least the fasteners are much larger. This means you're rear yoke would have to be swapped out for the larger piece. Combined with a DS loop, you should be set for max launch!! Keep us informed, freaking madman! I love it! The site Fabian placed up is awesome, they have some very nice components, the yokes are sweet! Jeff, did you check out the hardware?

airfuelEddie wrote: but the Chrome-Moly steel is the strongest.

Actually, there are shafts that are even stronger than that : carbon fiber...

My aluminum driveshaft has 1350 u-joints.

fbernard wrote:

airfuelEddie wrote: but the Chrome-Moly steel is the strongest.

Actually, there are shafts that are even stronger than that : carbon fiber...

My aluminum driveshaft has 1350 u-joints.

Yes, you are right about that Fabian, I didnt think he was interested in the Carbon/Polymatrix style of shafts so I didnt include that type. I hope Jeff upgrades his strap style u-joint fasteners to the 'bulletproof' 1350 style of u-joint 'U shaped' straps, like you have. They are much stronger than his 7260 small joints and weaker style factory straps.

eddie do uy have any pics of the two straps u mentioned......i have the strap type but not sure if its hd or not........

Jeff the only straps I know of are standard duty. It's not so much the straps but the small fasteners that secure them. The size of the fastener is 5/16? it's smaller than the U-bolt strap fasteners which are 3/8 I think. Scroll up to Fabians link on inland empire and you can see for yourself. Plus the strap types are only torqued to 20-25 inch pounds. They are always overtorqued when replaced, and you should just get new fasteners for the strap type anyways. To convert to the U-joint style I'm almost sure you would need to change yokes as well. Here is a pic of the strap/hardware for both 7260/7290 ujoint/yoke combo's BTW, Jeff, I'm pretty sure the 1310/1330/1350 Spicer yokes were never used in production MoPar muscle era cars. Those are for serious racers or guys who want the very strongest drivelines, they were used primarily in 1 ton trucks or larger. They are virtually bulletproof but would require the yoke to be swapped out for the yoke thats designed for the larger fasteners. http://chucker54.stores.yahoo.net/ujstrapandbo.html If you are going to 'drop the hammer' on a regular basis or add a nitrous kit in the future, I would seriously think about saving my money and upgrading to the shaft and u-joint type of setup like Fabian has, either in steel or alloy, the u-joints will let go first, then the damage will escalate, you dont want to go there again!

thanks eddie.....yeah thats what i have...they have a real small bolt head....i think it take a 7-16 socket?.........and i do have the smaller of the two pig yoke.......so i would have to change that as well then when i upgrade my drive shaft as you mentioned before.......so if i get this all straight then i need to go big on the u joints.....diff rearend yoke....and new shaft....either 3 inch or 3.5 or 4.......my 3.5 stainless and crossover tube my come into play there....guess ill measure my current shaft and see how big it is as far as circumfrence.....im assuming thats what they mean when they say 3,3.5,4...........what about a front yoke u think?.....go with what comes with dennys or upgrade to moly?

Sounds like a good plan Jeff, Yes , you'll have to upgrade the rear yoke and the slip yoke at the front is no problem it just slides into the rear of the tranny, tell em of your plans to use a power adder and they will recommend the right set-up,(Denny's). Yep, they are referring to the diameter of the shaft 3" 3 1/2 " ect Check the exhaust but I'm sure it will clear, if not no biggie, any exhaust shop can section it for you, then replace it with pipe that clears. I would get the strongest parts you can afford, because of the engine's power and the fact that you are a little nuts like me. Nitrous dude