I have a 1979 L-48 with the stock engine (some mods) and stock tranny. I think the guy I bought it from put in a different rear end. I am doing about 4000 RMPs when I am doing about 80MPH. I talked with a friend here and he said that I should put in a different rear end. My question is which one? I prefer to have a street driver that gets average gas milage rather than a race car that gets about 7 mpg. I am worried that if I go to fast, something will break......I really don't like red lineing it all the time. It is fun pulling away from the green lights though.

Any ideas on what I should get or where I should get it from. Don't want to spend an arm and a leg either.

 

I have a 3.07 in the Starship.
Check your rear end and see what your ratio is.
If you want to change the ratio, you only have to change the gear set, not the whole rear end.

 

Starship,
I am new to this and I am not sure how to check my ratio. I looked at the rear end and it looks like I will have to drop the rear spring just to open up the rear end. Is changing the gear set possible if a newbi? Do you have a suggestion as to what one I should get?

 

The only info I could find shows the '79 came w/ 3.55 gears. This sounds about right as mine runs about 88 mph at 4 grand and that's w/ 3.55 and 255/60-15 tires.

BTW do you really go 80 so much that you might break it?

 

Use the Richmond Gear Calculator

http://www.richmondgear.com/101032.html

Stock tire height is 27 inches, plug that in to the calculator.

If you want the best rear for a really good price contact Gary Ramadei, he rebuilds them the right way. PM me and I'll put you in touch with him. Gary will also help you if you want to rebuild it yourself. I have a used rear for sale on ebay for cheap that can be used as a core if you want to keep your car on the road while the rear is being built for you.
Be careful where you get your rear rebuilt, not everyone can do it right, ask me how I know..... I spent extra $$$$ because I tried to save some $$$$ the first time around. This way you can buy some more LED's with the money you save (just kidding).

As far as gear choices are concerned I would suggest a 3:07 or a 3:23, 3:55 and above are good for the drag strip but are not good for the highway. I lean heavily towards the 3:07 with the stock tranny (1 to 1 final drive gear), that will give you a decent cruising RPM that you can live with. Now - is it a manual or an auto trans and do you know what the 1st gear ratio is?

 

73 Shark,
I like to go fast but I don't know how fast I can go. It just sounds like when I get up there crusin, it is really screaming.
Dee Vee eight,
I have a friend down here in Virginia Beach in the Street Dreams Corvette club that is going to help me switch out the rear end. I would like to get all the parts and everything first so i am not tying up his lift for a week. He was also recommending a 2:70?? (did I get that right?) to help out even more. My car is an auto but I am not sure what the 1st Gear ratio is, don't know how to find that out. My speedometer gear in the tranny is broke (being shipped) so I will figure out my speed/rmp here today with my gps to figure out my gear ratio.

My friend said not to just put in new gears, buy a new rearend, but what I saw in the summit mag they are about a grand. Is that right?
Thanks.

 

I'd be leary of buying a rear from anyone, even Summit, for our Corvettes. Your best advice will come from Gary, he is in Connecticut and can build a rear for you and probably do it for less than what Summit wants. If you have it built by Gary it will be done right the first time. I had Gary build a steering box for me, it was money well spent.

 

DeeVeeEight,
I used the calculator to determine the gear ratio and it came up with 4.02 (70mph at 3500 rpm). I will keep Garys name in mind as I get ready to decide if I want to change the rear end.

 

Sounds like someone swapped in a 4.11 set. Not good for street driving. 3.36's are basically the best of both worlds. I have the original set in the 69. I have driven for 7 hours on the interstate at 75 and I get about 15 MPG. They are still low enough to set you back in your seat with a decent engine combo.

 

Looks like I will switch my gears out. I have to do some more research to see if I can do it or if I will just buy a new one.