Poll 3.55 or 3.73 Gears

[BanditSVO]

Im in the process of a 8.8 overhaul for my 86 svo. Should I stay with the stock 3.73 ratio or go to 3.55 ratio for better freeway gas milage. My car is not stock it has a ported head and a hybrid turbo boosting up to 17psi so that should make up if i go to 3.55's.

Here is my 8.8 build list

- 91 Mustang GT Housing
- Motorcraft Bearing, Shim and Seal Kit
- Motorcraft Trac-Lok Clutch & Shim Kit
- Ford Racing Gear (Undecided Ratio)
- Moser Axles

[Ken Potter]

Well since you already know how it drives with a 373 I guess trying out some 355s couldn't hurt. I've always felt first gear was too short and useless with 373s unless you do a lot of stop and go driving.

You can always change back to 373s if need be.

[bob tweedy]

gear

in the 'for what its worth' dept i like the 3.73s so well that i have put them in my 99 cobra and my 79 king cobra and of course my 86 svo has them.
bob

[svono50]

I vote for the 4.10's...wait you didn't have that as an option, my bad

The 3.55's will likely get you better gas mileage, but it comes down to personal preference. While I was happy with the stock 3.73's I had the opportunity for the 4.10's with my 8.8 install and I was drag racing at the time. I have been running 4.10's for more than 10 years and love them, even on the auto-x and open track days. I still pull down 25+mpg at 75mph, which is running at about 3200rpm and my car is not stock. I hit 3000rpm @ 67mph due to my slightly taller than stock tires for reference.

[Raven855]

I like the 3.90 and 4.10 gears better. Then again I like the TC ratios better too.

[caroth]

Stock transmission? Do you drive above 75mph? Do you have a chip with the closed loop RPM raised? Your fuel mileage will suffer if you routinely dirve about 3000rpm on a stock computer.

I have the 86 SVO T5 with the 3.50:1 1st gear and run 3.55 gears and love it. I have also tried 4.10:1 gears and hated them, it made 1st gear useless. My car is not stock, makes more horsepower than stock.

[MeZapU]

I've had 4.10's and now 3.55's. I would prefer something in between. My 3.55's came with my turbo coupe 8.8 and it only cost me $100.

[BanditSVO]

Yes I have the stock t5 and I dont really drive over 75 mph, only to pass cars in the feeway do i go over that.

[BanditSVO]

I don't drag race my car or race it at all. I just figured that my MPG would improve if i go to a higher gear ratio while doing freeway driving.

[NinjaBOY]

I think you need to also state which tranny you're running with, and what the purpose of the vehicle is. I just put a set of 3.55's in the 'Trash car because I wanted to be able to run at the track in 4th gear. The car also has a TC tranny in front of it, which has a shorter 1st gear, but better OD gear.

I had an 84 SVO with the stock tranny and put in 4.10's. That made 1st gear worthless, but it was a hero from 2nd on. That car was heavily modified and still got 21 mpg.

For the street, I'd stick with the stock gear combinations. Eric Martin has the 86 svo tranny with the 3.45's in the rear. Gets good gas mileage, but needs to downshift to 4th when climbing hills.

That's my two cents worth...

[BanditSVO]

The car is mainly for getting around town and going to places mainly will see freeway. I already own a 800rwhp turbo camaro to race

I have the stock 86 tranny the car came with.

[BanditSVO]

I was just thinking 3.55's because I have read of people getting way better gas milage being under 3k rpm on the highway. But I guess it seems that most perfer stock gear's.

[blueboss]

If you do any freeway driving at all.....3.55's. Or run 3.73's and run larger tires.

[Desi]

Running 3.55's in the IRS & I really like the range of gear I have, don't have to keep shifting all the time & 1st actually is useful.

[cheapertokeepher]

Running 3.55's in the IRS & I really like the range of gear I have, don't have to keep shifting all the time & 1st actually is useful.

Are you using the 84 tranny?