jgalfo

I have a D36 with a 2.59 ratio now and want to purchase and install a completely rebuilt pumpkin for a D 36 from Ecklers with a 3.73 ratio. they have a electronic adapter that will calibrate the speedo.

should it be a easy swap?

Will I notice a good "seat of the pants" difference in performance with my stock LT1, car has 61,600 miles

parts are about $1300. would you do it if it were you

all advice/ opinions welcome good or bad.

WVZR-1

I believe way to much gear BUT if it's a '95 you should be able to do speedo/odo calibration in the PCM and you won't need the ERA/DRA from them. Is there a particular reason you've chosen them for the package?

jgalfo

no reason other than everyone can look them up easier.

are you suggesting a 3.53 gear or a smaller 3.07?

why, what are the negatives you see?

johno504

how is a 3.73 too much gear? i did a 4.10 in my 90 , nice in town but gear bound at high speed. 3.73 should be juuuuuuust right.

drcook

3.73's and 4.10's are nice in town and on the track, not so nice on the highway or when passing a gas station. my 3.07's get less mileage than the other folk's around here cars with the 2.59.

I like the 3.07. My car is a '96 and with the 4l60E trans I have, I am turning just about 2000 rpm at 70 mph.

I do wish they had 3.23's though. My 1991 454 pickup has 3.73's. It was built for towing. My '04 Duramax diesel has 3.73's but they are made much more easy by the Allison transmission.

it probably all depends what you want out of the car. we like to jump in it on a sunny day and do some long drives. it is not fun when a couple long drives cost you enough to buy a set of full roller rockers.

just my opinion

C409

..... Your trucks have MUCH taller tires ... that changes the overall gear ratio/revs per mile ... I'd think that there is something wrong with your car if you are consuming that much gas ... figuring 18mpg , you would have to drive around 2K miles to consume enough gas to pay for decent brand name full roller rockers ... 2000 miles is definitely a long drive .....

..... OP go with the 3.73's ... you'll be glad you did ... just don't plan on taking the 'vette cross country .....

sprink94

They also have a 3.55 available.http://www.ecklerscorvette.com/corve...984-1996.html#

Where did you see that price on the 3.73?

jgalfo

Ecklers has them for $1500 and some change but the are giving 20% off orders over $350. so that brings the price to about $1300.

drcook

1. I do understand gear ratios, tire sizes etc. I changed the tire size in my trucks to slightly drop the gear ration to get better mileage pulling a trailer, been pulling horse trailers and travel trailers for 27 yrs now, with trucks having 4.11's and 3.73's, gas and diesel motors. I know how little changes affect gas mileage in a big way.

2. nothing wrong with my car. I get mileage in the low 20's, it seems that the couple folks that have the 2.59's are getting 27+ on the highway. a 5 to 7 mpg drop can start adding up over the stretch of time, if you do the math. on a 1000 mile trip a 7 mpg drop equates to a $45.5 difference in fuel costs. That 7 mpg average can be skewed lower or higher depending on driving style, more city or highway driving, time of year and fuel blends.

so for a person who only drives the car minimally they won't see as big an impact as the person who uses their car for a daily driver

but in my book, that 45 dollar difference starts to add up. am I cheap no, but I have learned to compromise to get the most out of each dollar.

3. discussions like this have been going on before, both here on the forum and all around other forums and tech sites.

such as:

https://www.corvetteforum.com/forums...-3-73-a-2.html

some folks like the stiffer gears, some didn't. some saw 5 to 7 mpg drops

4. when a person considers a big change, like 2.59's to 3.73's, torque converters have to be talked about also

http://www.badasscars.com/index.cfm/...rod/prd446.htm

https://www.corvetteforum.com/forums...-low-down.html

the above are good reads and one a discussion amongst board members here. Notice a lot of the talk involves drag racing.

if the OP is interested in a "drag race" type of performance, meaning quick starts and quick acceleration with no regard to where the engine spends its time RPM wise the rest of the time, then do the 3.73's, the RPM will stay in a higher range and eat more fuel and wear parts quicker.

but if the OP is just wanting a good compromise, then the 3.07's or possibly 3.54's will work. my 96 will bark the tires going from 1st to 2nd with the 3.07's and it is easy to drive. not revving to the moon like an anemic 4 cylinder that the automakers had to use stiff gears in to get it moving.

IF I was building a drag car, my thoughts and opinions would be different, my thoughts are based on building an all around driving/cruising machine that I can enjoy as opposed to some of the cars I see at the cruise-ins. Will they fry the tires, of course, hold you back in the seat, of course. Do they do the trip to Florida Nope. Will they out run my car on a straight line track, yep by a mile, but they can't go on an enjoyable, spirited drive either.

1994BlackRose6spd

3.73!!! Do it! I think you will like it!

johno504

my 2 cents, anything less tan 3.5 is a waste of money

DGXR

It should be a relatively easy swap if you are good with a wrench and have some patience and an extra pair of helping hands (you may not need them but it's good to have them available).

Yes you will definitely notice the difference in your pants. Regearing of the differential is one of the best performance mods which is not a "power adder." It will give the engine more leverage to sling your car forward, so the performance will be significantly improved without modifying the engine. Personally if I wanted more performance, this is one of the first changes I would consider.

As discussed, the obvious drawbacks are top speed and fuel economy...also you will be down $1300 or more. But fuel economy is probably not a concern for those looking to increase performance, they don't normally go together

I would not do this change to my car simply because I am happy with it stock, it runs great and everything works smoothly. I love cruising 75 mph at 1800 rpm (6-speed).

jgalfo

I just ordered a rebuilt differential with 3.54 gears from Zip Corvette for $999.99

FYI Ecklers would not come off their price and said the advertised discount offer of 20% on orders over $350. did not apply to differentials. Ecklers were asking the full price which is more than $400. over what I paid. in addition they wanted a $450. core charge and I paid $400.

just an FYI to my fellow forum members.