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LUDELVR
06-23-2002, 11:03 AM
has any one had this problem before, the boost in first gear is significatly lower than the boost in third? Actually, when I'm in first gear and second gear, I boost about 1-3 in first and then when I shift to second, I can usually get 4-5 and from there on, I can boost my full 6-7 psi. Why is this happening? I have an internally set wastegate at roughly 6.8 psi and at the moment I'm running the intercooler from the drag kit (which I believe is a spearco) and I'm not sure how much the pressure drop is but I'm just wondering why I'm not fully boosting the 6.8 or so psi in first and second gear. Thanks guys.

rage2
06-23-2002, 11:33 AM
Your turbo is too big =). There's not enough load in 1st and 2nd gear to generate boost. I get the same problem... only 16psi in 1st gear.

legendboy
06-23-2002, 11:38 AM
would a T3 be a good size for 1.8L? Stock redline of 7200.

Redlyne_mr2
06-23-2002, 01:11 PM
ya dude rage is right, your turbo is too big for your setup, remeber what size of engine you got that from...sorry to here youkeep having turbo problems, I know how frustrating that can be, maybe you shoudl go with somethign smaller

LUDELVR
06-23-2002, 01:31 PM
Originally posted by Redlyne_mr2
ya dude rage is right, your turbo is too big for your setup, remeber what size of engine you got that from...sorry to here youkeep having turbo problems, I know how frustrating that can be, maybe you shoudl go with somethign smaller

I wonder how the ct-26 from the mr2 would work. I mean, it's the same trim on the cold side, but the mr2 has a 2 liter vs. a 3 liter 6 cylinder.

Redlyne_mr2
06-23-2002, 01:35 PM
for the smaller displacement engines the mr2 wokrs much better, I know guys who have used it on the ford festiva engine.

LUDELVR
06-23-2002, 02:33 PM
Originally posted by Redlyne_mr2
for the smaller displacement engines the mr2 wokrs much better, I know guys who have used it on the ford festiva engine.

Yah, but I have a 2.2L and what's a festiva....almost 1!!! hahahaha

LUDELVR
06-23-2002, 02:34 PM
Originally posted by rage2
Your turbo is too big =). There's not enough load in 1st and 2nd gear to generate boost. I get the same problem... only 16psi in 1st gear.

so 16psi is low boost for you????:eek: :eek: man, u r a high roller!!!!! ;) :rofl: :thumbsup:

So what would happen if I cranked up the wastegate to allow 9 psi? Would I still not have enough to push more than 3 psi in the lower gears??

redline
06-23-2002, 02:54 PM
I would say that it is not a size issue, (that’s what they all say) Cause my turbo is way bigger and I get what ever boost I want in the first couple of gears.

Those CT turbos that toyota uses on those cars are just plain ass. It is an efficiency thing more then a size issue. My friend has a turbo supra in that year and he has a hard time spooling the turbo.

For junk yard turbos I would get a t3 super 60, or a 1st gen DSM turbo. If you are going to buy a turbo for a b18a/b I would use a stage2 48 trim on the hot side and a 50a/r 50 trim wheel on the cool side

For a vtec car I would use a stage 3 .63 t3 on the hot side and a 50a/r 57 trim wheel on the on cool side.

redline
06-23-2002, 02:55 PM
Originally posted by LUDELVR


So what would happen if I cranked up the wastegate to allow 9 psi? Would I still not have enough to push more than 3 psi in the lower gears??


an EBC will help the turbo to spool better along with a full 3" turbo back exhuast.

rage2
06-23-2002, 03:03 PM
Originally posted by redline
I would say that it is not a size issue, (that’s what they all say) Cause my turbo is way bigger and I get what ever boost I want in the first couple of gears.

Size is definately an issue. He doesn't get boost until 4000rpm. In 1st gear 4000rpm- redline should happen quite fast, not enough load to get the turbo spinning up to speed.

Oh, and I'm bitching about 16psi in 1st gear because I can run 30psi in 3rd gear if I wanted to, the turbo's big enough to give that much flow and boost.