8UpAFord

I know it’s not an F-body, but I like to ask people on this site. There is more knowledge here then a lot of other sites.

Anyway I have 88 Vette with 2:59 gears housed in a Dana 36. I’d like to try to find 3:07 or 3:33 but I think they discontinued them. All I find out there is 3:54 and 3:73 which I think might be an over kill on a L98. My question is, does anyone have 3:54 or greater in there *stockish* F-body *L98*and *700R4*? Is it an over kill with anything higher than 3:54? If you all can let me know about what it feels like pros and cons.

I have a kinda stock L98, this one has, Modified BIN, some bolt on parts, exhaust cat back, ported upper lower plenum, runners, and Air box. 1-2 2-3 Transgo shift kit. For most part it’s pretty mild mods but runs extremely well. I can cook the tires at a standstill as long as it’s not a really hot day out and the tires get sticky. Future is an LSx, next couple years. Of course 3:54 would be nice in an LSx


Thanks in Advance

//<86TA>\\

iTrader: (15)

3:45's were a stock 9 bolt ratio in some tuned port cars. not sure if i would go more than that on a relatively stock TPI engine

jmd

iTrader: (4)

You're right in being somewhat conservative with gear choice since your L98 is running a stockish intake manifold (and cam?)

3.54 is a good choice. Unless your goal is hwy. mileage, go for those. It will drive nicely with less pedal to get you up to speed and the 2.48 ratio in 4th gear will be very tractable at moderate to high speeds.

8UpAFord

I don't have a cam. It's all been ported. The heads are not ported though. Do you think I should slap a CAM in it I rather not invest to much more in the motor? Also wonder what my RPM at is going to look like at 70MPH, my guess is 2200 or 2500? I'm sure it would be smoking tires none stop bottom end, but I wonder how bad my Top end would be? I mean 2200 at 70MPH I could live with any more than that would be a little silly.

I wonder if I should keep looking around for 3:07s or 3:33. I think 3:33 would be about perfect.

jmd

iTrader: (4)

If you think you will change intakes or change engines entirely in the future, skip the cam for now. The TPI intake chokes things, even when ported. It sucks to go from a 4bbl and healthy cam to a TPI intake with that cam because it highlights how bad the intake is.

With a 26" tire at 70mph, RPM is usually close to this: Diff. ratio (3.54) * top gear (.70) * 1000.

So 2478 with 3.54 rear gears.

8UpAFord

thanks man. You are right, I need to think about the entire setup. I like the sound of 3:54 gears but with this crappy TPI it makes my stomach turn. I wonder if I should rather do a carb setup rather than LSx, I think carb would be cheaper too. At least time the 350 is blown.

AaronIROCZ

iTrader: (5)

Gotta lock this as it is not thirdgen fbody related. Please PM me if you have any questions.