I just bought a 85 trans am 305TPI automatic about a week ago it has the ws6 handling package and 3:23 gears i believe and it has 38k original miles and it is stock and im going to the track this weekend and i was wondering what times i will see and i was thinking about putting dynomax exhaust on it soon and i need some other ideas for some cheap mods

 

mid 15's

 

look at my sig, i ran pretty good, make sure when u do run, to put ur car into D and no OD... u will get better line pressure in ur trans... the cam in the 85 and 87 are different... but u should be able to pull it off.... i aimed for a 15.5 and got at 15.3... i want to upset... next summer comes all new exhaust... good luck

 

In GM High Tech Performance they just put a Dynomax 3 inch catback on a 305 TPI Formula and picked up 2 tenths and like 1.5 mph. Sounds like a good choice if you're looking for performance out of the exhaust. I'd say you'll hit low-mid 15's if the cars in top running condition.

 

It all depends on where u live. A stock 85 should do 15.2@89mph at sea level. For times with the 1985 IROC check out the sig. Runs were made at 4400ft above sea level.

 

I'd say if you did cold air intake with and exhaust setup AND a high flow cat (just for that little bitty extra cute gain) you could run a flat 15 with everything properly tuned up. Headers - just to make sure if youre willing to throw down some more bucks would definitely get you in 14.85 range i would be confident saying.
Too bad you got the auto, cause the 305 TPI's had so much more to offer with the 5spd. =P

 

i expect that you will run around a 15.6-15.8 at sea level stock beacause on a nice day at aound 73 deg. at englishtown race way in NJ which is at see level alot of thirdgen tpi 305 auto birds where there

all of them where stock and runing about 15.6-15.8

this is the same day i ran my 14.86

 

in 85 you werent able to get the tpi and the 5 spd, only the auto

 

"i expect that you will run around a 15.6-15.8 at sea level stock beacause on a nice day at aound 73 deg. at englishtown race way in NJ which is at see level alot of thirdgen tpi 305 auto birds where there

all of them where stock and runing about 15.6-15.8"

the 85's should run a lil better due to the cam. also take into acount that the stock firebird intake ducting sucks anus.


that being said, do what i did on my old bird, rip the pos air box out and buy a universal K&N cone w/ the same inlet size as the ducting that led to your air box.

 

U should do allright, just dont expect anything.
Let us know when u have times.