I currently have a PT4000 w/ 3.23 gears. I got a whole half of a pass out of the converter before the tranny went boom. While the car is down, I was thinking about putting in 3.73's to replace my stock 3.23's. The gears I will use will be the genuine GM kind, so hopefully noise and strength won't be an issue.

I did a search and I found that people were saying that with this converter, higher gears are a waste of time. Is this true? How many of you are running 3.23's w/ a PT series converter and what are your 60'? Same with 3.73's? Just trying to get some info before I buy 'em.

 

I have a TCS4200 with 3.73 gears, I would not say going from 3.23s to 3.73s is a waste. You should pickup at least .10 and maybe a bit higher trap speeds. The 3.73s will also help tighten up that PT4000 of yours.

 

PT4200 and 3.73s = 1.50 60ft on BONE STOCK SUSPENSION

 

With my verter I picked up 2 tenths going from 3.23s to 3.73s. I cut a 1.54 cam only.

 

just less than .1 making the exact switch when i was bolt-on. picked up 1 mph.

SOTP said the gain was huge, but track results said otherwise. Drivability definitely improved. For street racing, I liked the 3.23s better. I found it much easier to launch the car in a stoplight race.

 

I remember a few weeks ago in one of the PT series efficiency threads where someone said that the PT series converter won't see it's best efficiency until you move up to a 3.73 or bigger. Is this true or did I read that wrong?

 

Roughly a tenth gain or a little less. Worth it? That's up to you. I like my gas mileage in my daily driver and pulling 1.50 60s (or even 1.4s) is well possible with 3.23 gears.

 

Have any of you guys broken your 3.73's at the track?

 

I have a PT4200 about to be installed and have 3.73s now. Driving is snappy around town, but traction is tough from a dig. Would I loose a whole lot by stepping down to a 3.23 in my new Strange 12 bolt? Would my 60' suffer much? Thanks.

 

John, that's basically the same question asked backwards. Read the above responses. Your times might suffer a tenth at the most. The biggest difference would be the feel of that converter with 3.23s. It will be somewhat looser.

 

why not split the difference and live in both worlds and go with the 3.42s?

 

Will traction be much better by getting 3.23s over 3.73s? I have 3.73s now and can't decide what to put in my Strange 12 bolt. Thanks.