View Full Version : Can't get full boost in fisrt gear
lazyeye
04-03-2004, 12:34 PM
I am currently having a sr20det swap into a 1990 240sx done by XAT racing in Tampa, Florida and I read this and was wondering what you guys thought -----> ""The factory computer limits the boost in neutral, reverse and first gear. In Neutral and Reverse, the car is normally aspirated. In first, it's limited to a small amount of positive pressure.""
this is from - http://www.200sx.org/index2.html am i going to have this same problem with my 240sx? thx for the help!
PSI240SX
04-03-2004, 01:47 PM
Never heard of that. But I can tell you with more load comes more boost. In first gear you may not get as much as the rest but it will be close enough to not notice. Its much more noticable on larger turbo cars. Usually the tires spin and the gear is over so quickly, there isn't enough load on the motor to build full boost.
If your running stock turbo, you wont have to worry about this.
Maeda
04-03-2004, 02:26 PM
Yup. I can't hit full boost in first, not that i'd want to swap ends suddenly...
andrave
04-04-2004, 05:56 PM
its normal to not hit boost in 1st gear.
as for the no boost in reverse... I dunno, but my friend's evo makes plenty of boost in reverse. I can't imagine there would be too many times when you would be going in reverse with enough load/long enough time to produce much boost. someone try it and watch their boost gauge.
okashira
04-04-2004, 11:58 PM
I can get full boost in 1st. not a good thing for me... damn 35 lb flywheel.
Big Burt
04-10-2004, 04:55 PM
I agree with the load thing. My SR will not get any boost in neutral cause there is no load. With a manual tranny it must be in gear. Also 1st is so short you dont have enough time to get more than 10psi at the most. If you start peelin that can cause boost to drop off a little also. However my buddy at school has a ranger w/2.3 turbo motor and somehow the damn thing blows off crazy loud in neutral, but it also has a t3 with a greddy bov and I think external wastegate.
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