Upgrading gears... stock/3.07/3.23/3.73

[BoostedVR-4]

My friend and I are always chatting about cars, and I'm all for much better gearing, instead of a small change from the stock 2:73 ( I'm no expert on the C4 specs ).

He'd like to upgrade to 3.07's, and I'm trying to convince him otherwise. It's not his daily driver.

I suggested 3.23 AT LEAST. Does anyone here have upgraded gears and can assure him which to go with?

How they work with......
- Cruising around town
- On the highway

 

[Moonunit 451]

What car and tranny and rear does he have?

 

[BoostedVR-4]

700r4 /4 spd auto... d36

 

[Moonunit 451]

700r4 /4 spd auto... d36

I'm not sure what gear ratio's besides the 3.07's and I think 3.73's are available for the D36. I think there might be a 3.45.

I went to a D44 with 3.33's in my car, and I gotta say they are ideal for all around driveing. So far I haven't been able to hook even slicks at the track, and she's not breathing hard at 140, around 3800-4000 R's as I recall, so they are a pretty big improvement over the stock 2.59's.

 

[Hrtbeat1]

I'm not sure what gear ratio's besides the 3.07's and I think 3.73's are available for the D36. I think there might be a 3.45.

I went to a D44 with 3.33's in my car, and I gotta say they are ideal for all around driveing. So far I haven't been able to hook even slicks at the track, and she's not breathing hard at 140, around 3800-4000 R's as I recall, so they are a pretty big improvement over the stock 2.59's.

There is something about being two size carriers for the D36. The small one will only hold up to a 3.07, and the large will go up to 4.?? with Richmond or Strange gears. I'm not sure about that, but its what I've heard. For the most part the D36 came with 2.59, 2.73, or 3.07 gears.

I also went with a D44, but 3.45 gears, I wanted 3.33. I must say the acceleration I get with these is much more impressive than the stock 2.59's. I think I need to go with a wider rear tire to help with the hookup. I could barley get the 2.59's to spin, but the 3.45's spin at will, 1/2 to 3/4 throttle

 

[BoostedVR-4]

I see, so depending on his rear end he has a few options, I'm so used to the newer setup with ls1, t56, and with some of the real upgraded cars around here, strange 12 bolts, etc..

Typical gears are

3.23
3.42
3.73
4.10

Guess his best bet is those 3.33 if he can get them for his rear end.

 

[Hrtbeat1]

Guess his best bet is those 3.33 if he can get them for his rear end.

That would be a good choice. The D36 is weaker than the D44 but there is a member here that has a stout D36, so it can be done.

You can tell the ratio you have by the RPO code, providing it hasn't been messed with.

GM1 = 2.59
GU2 = 2.73
G44 = 3.07
GT7 = 3.33
GM3 = 3.45
GHO = 3.54

 

[Vettefan87]

Yeah it is my car, we are talking about. It has the GU2 RPO code so they are the 2.73's. I would like to upgrade the differential since the 36's are somewhat weaker. I was thinking somewhere in the ballpark of 3.33's. I know 3.73's are way to high. Guess I have to start saving again.

 

[Hrtbeat1]

Here's a link for future reference. They normally have a couple D44's, maybe in the ratio you want. I think they charge around $1500-2000.

www.corvettesalvage.com

 

[Vettefan87]

What kind of fuel economy are you guys getting with these different gears?

 

[regalniz]

i had 3.07's in my d36 with auto tranny. i went up to 3.73's. big difference. i dont chirp second, i spin through second. mileage did go down but if you wanna play, ya gotta pay.

 

[Vettefan87]

i had 3.07's in my d36 with auto tranny. i went up to 3.73's. big difference. i dont chirp second, i spin through second. mileage did go down but if you wanna play, ya gotta pay.

What kind of fuel economy are you getting? I checked my vette the other week and I got 16.8 mpg that is with driving around city, and Gteching the car a few times so I don't think that is bad. I pretty much have my mind made up that I will get a D44 with 3.33's in it.

 

[Moonunit 451]

What kind of fuel economy are you getting? I checked my vette the other week and I got 16.8 mpg that is with driving around city, and Gteching the car a few times so I don't think that is bad. I pretty much have my mind made up that I will get a D44 with 3.33's in it.

22-24. 3.33'S. I'd do much better on a long trip at 60 - 80 mph And I've run 12.2 with out a final tune, and I haven't been able to hook the slicks yet, no matter what I do, 1.75 is my best 60" :bash I can easily run in the 12.3's consistantly

 

[regalniz]

i get 16-17 miles. i could do better. once the doctor removes the lead from my foot. if you got 3.07 or lower, going 3.42 or 3.55 or anything middle ground like that will dissapoint you. if your gonna do it, then do it. but i wouldnt go higher than 373 with a d36. mileage between a 342, 355, or 373 cant be that much. i was more concerned with the engine wear. 373 will make the engine cruise at a higher rpm. i think i do about 2500 rpms at 60. where i was at 2000 rpms at 65 with 307's.

 

[Moonunit 451]

I NEVER get on it

 

[Hrtbeat1]

With the stock 2.59's I got 26-30 MPG if I kept my foot out of the TB. Actually got 32 on one tank-full (interstate @ 77 the whole way.)


With the 3.45's I am getting 20-22. If I run it hard it will be in the single digits, maybe low teens.

Yet to go to the track but G-tech 60 foot times were 2.0 to 2.1 with the 2.59's and stock converter. With the 3.45's I'm pulling 1.7 to 1.8 60 foot times, I think the 3 clutch 2200 RPM converter has a lot to do with the better times, that and the new gears. It will be interesting to see how accurate the G-tech is when I get a chance to go to the track.

 

[Vettefan87]

Yeah I think 3.33's or something around that area is best considering I do drive the car somewhat, and would like to take it for a half hour drive up to our lake cottage without filling up twice just to get there.

 

[Vettefan87]

Considering how much the Dana 44's are going what kind of gains would I get with just putting 3.07's in my 36 now? I would still have to change the speedo gears and what not too correct?