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View Full Version : has anyone else experienced problems like this


Big Burt
04-04-2004, 02:41 PM
First of all I have a 91 240 with a sr20 (stock - ka mounts, sr fan and shroud, sr radiator, sr smic w/duct and factory plastic piping, clutch, no LSD, crappy struts, and some wonderful champion copper spark plugs.) (aftermarket - Blitz SSBC, Blitz bov, apex turbo timer, 3in turbo back w/heavythrottle 3in cat, K&N filter,walbro255, autometer boost and A/F, eibach crappy .75in lowering srings, enekei knock offs 17x7.5 w/no traction 215/40 nitto 450's, and crossdrilled front rotors.

I went to the 1/8 mile dragstrip friday night. I had to drive 50 minutes to get there so my car was nice and hot and not running the best it could. I experienced a lot of stupid problems, the main one that pissed me off was I had the boost set at about 14 when I got there, but when I ran it spiked at 12 and settled at 10 so I cranked it up all the way and no change. My buddy was sayin it could be heatsink problems with the smic. So I let it chill for a while and sprayed down the intercooler with water. Then I put some 104 race gas in and back off I went I had been running 9.3, 9.4's this time I ran a 9.1 at 81.27mph 60ft was 2.27 and with tons of wheel hop, this was the best I got it to, I felt pretty good about it since that time I hit like 12psi and held it. I want 8's really badly though. Yesterday I changed the oil and saw some fluid spots on the ground while I was down there, only back by the tranny. Sure enough it's the outputshaft seal my question for you guys is can I use the seal from a maxima rear drive tranny or 240 tranny?

The other thing is, the car will boost 15 from 3-6 grand until I've been driving it for more than 20-25 minutes, then it starts spiking at 13 and settling in around 10-12. (daily driving is done at stock boost, but sometimes you get a little bored) Could the bov be leaking boost , cause all vacuum lines are secure and new (I put in the motor 12-20-03) or could it be that its just running hot?

I greatly appreciate any answers you guys have.

OldSklS13
04-04-2004, 03:02 PM
i have limited experience with this at this point, but since no one else has said anything i figured i would give my input.

I think you are maxing out the sr smic by trying to boost at 15psi. Its efficiency peaks at around 10psi. Past that, youre just pushing hot air around. That might be one source of your problem.

drift freaq
04-04-2004, 08:02 PM
word: you should not!!! repeat should not!!! run a t25 at 14lb's its pushing pure hot air. T25's are absolutely no good above 12lbs. In fact with a stock T25 I would not take it above 10-11lb's of boost.

Big Burt
04-05-2004, 06:52 PM
Thats wierd, I heard not to go above 13psi by someone who has done many sr swaps and has owned two himself. I've been runnin 13-15 around town for about 3-4 months hangin with c5 vettes and other crazy things. T-25's efficiency range is supposed to be 15 at max and after that your risking all kinds of stuff with 370cc inj. and the smic. Plus, man it feels great at 14. I run 9-10psi every time I drive and I dont push the high boost button unless its necessary. Plus I plan on gettin the t28 ball bearing anyhow. Thanks for the input on the smic and boost level i'll have to check into that more.

Phlip
04-05-2004, 09:27 PM
I have seen and driven (not my own, a friend's) SR at 14 pounds of boost for a year and a half with ZERO issue... The difference? This cat (Steeles to you people) has HUGE Greddy FMIC, but the car currently sits with stock injectors and some other shit... I would call the issue in your case the SMIC, it's time to move up if you plan on boosting it seriously.