DragStuff

So are Aluminum cases ok for heavy cars and very limited street use? I'd read somewhere that it wasn't recommended. They don't seem to be that much more expensive given the weight difference but not worth it to me if I can take it to a cruise-in 8) .

Thanks,
John

The aluminum 3rd members are really not recommended for street use because they are very light weight but they flex alot. This will give you very poor gear life on the street. They are pretty much designed for drag racing where gear life is not an issue.

Thanks CoMax. Just to be safe let me quantify "limited street use". I am really talking maybe just 10 miles down the road before stopping to let cool. And that is probably only a very few number of times a year, e.g. 3-5. Heck my other car is a street car and it only has 900mi on it after 3.5 years .

I guess it is the extened driving times that causes heat to allow the aluminum to flex enough for damage? In which case it isnt the "street" necessarily but instead the extended run times?

Thanks,
John

Actually the aluminum cases flex strictly because aluminum is not as ridgid as nodular iron. If you are using the aluminum case for very limited driving and not putting huge amounts of horsepower through it (which is what flexes them in the first place) it will probably be OK. Just pull the 3rd member out once in a while to inspect the gears for wear.