Did the T5 swap last year. I have a 3:23 **** end. While it's much more fun to drive, I think the 700R4 actually felt faster. Wanted to know how much of a difference a ratio change might make. Considering a 3:73

 

It's pretty massive.

Too much for a TPI motor, even where you are, where the speed limits are absurdly low. Last time I was in Mississauga (and Vaughn and Etobicoke and various other nearby places...) acoupla months ago, I did have to drive about 90 km/hr once or twice, on the 410 and the 401. TPI limits useful engine RPM so bad, that you might find it slows the car down, because it'll reach the peter-out point too quick.

IMO 3.23 is probably the best all-around TPI gear, with the possible exception of 3.42. But IMO there's not enough difference between 3.23 and 3.42 to make that change, although if you had 2.73 or something, it would be a different matter.

 

i went from 3.23 to 3.73's with an lg4 carb t5 and noticed a big difference. now i'm sporting TPI and a tremec tko 600 with 3.73s and it's a beast of a street car

 

Basically you will be doing about 10mph less in each gear. So decide if that is what you want.

 

Good point. I do want to get around to changing the intake and runners to a better flowing system as well as the heads. Perhaps I should do that first. Not looking for a strip car by any means. Just want something a bit more punchy.

 

The V8 T5 ratios (I prefer the 0.63 fifth) and 3.73 rear is a very tractable combination.

Don't just change the intake and runners. Go for a whole intake swap. TPI sucks with 3.73s. In other words, a Q-jet is loads more fun on the same engine, assuming 3.73s.