why my turbo is so laggy!
#1
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just wonder wat rpm range would ur turbo kick in?? my turbo kicks in ~4000rpm at 1st gear, ~3600rpm at 2nd and ~3200rpm at 3rd, the high the gear is the lower rpm it kicks in, i wonder if it's programing problem or exhaust problem, also very intersted in ur exhaust setup, pls let me know wat kinda piping u're using:
here is my set-up
1.6L engine
Greddy Exhaust Manifold
Greddy 16G turbine with Garret TD04 Compressor
customized 2.5" downpipe with flexpipe
2.5" in/out high-flow cat.
2.25" exhaust b-pipe with 1 resonator
2.5" single in, dual out dynomax SuperTurbo exhuast
3" intake pipe + 2.5" intercooler piping w/starion FMIC
ACT ProLite flywheel + HD clutch kit (1.8L convertion)
Walbro 255LPH fuel pump
BEGI 2025 RRFPR
305cc Supra injectors
NGK 2 degree cooler spark-plug
Greddy Emanage Ultimate with MAP + intake temp sesor
AFM removed
TurboXS RFL BOV
TurboSmart Boost controller set to 10PSI
so i guess my fuel system is more then enough to handle 10PSI but the turbo is kinda laggy, is it becos my 2.25 exhasut piping + cat + resonator which hold it back, or the IC piping is too big...or smthg else possibly?? look forward to see any subjection or solution, thz alot.
here is my set-up
1.6L engine
Greddy Exhaust Manifold
Greddy 16G turbine with Garret TD04 Compressor
customized 2.5" downpipe with flexpipe
2.5" in/out high-flow cat.
2.25" exhaust b-pipe with 1 resonator
2.5" single in, dual out dynomax SuperTurbo exhuast
3" intake pipe + 2.5" intercooler piping w/starion FMIC
ACT ProLite flywheel + HD clutch kit (1.8L convertion)
Walbro 255LPH fuel pump
BEGI 2025 RRFPR
305cc Supra injectors
NGK 2 degree cooler spark-plug
Greddy Emanage Ultimate with MAP + intake temp sesor
AFM removed
TurboXS RFL BOV
TurboSmart Boost controller set to 10PSI
so i guess my fuel system is more then enough to handle 10PSI but the turbo is kinda laggy, is it becos my 2.25 exhasut piping + cat + resonator which hold it back, or the IC piping is too big...or smthg else possibly?? look forward to see any subjection or solution, thz alot.
#4
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i replaced the greddy downpipe with a 2.5" already, but still looking for a replacement for the manifold. and wat rpm range would ur turbo kick-in?? i am not sure if it's da back pressure which holds it back, or just da intake piping and IC piping are too big so there is too much free space for the boost to fill up b4 it goes into the cylinders. anyways, i will try removing my cat and resonator and see if it makes difference, but do u guys use 2.25", 2.5" or 2.75" for exhaust piping??
#5
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![Default](https://www.miataturbo.net/images/icons/icon1.gif)
As fas as "~4000rpm at 1st gear, ~3600rpm at 2nd and ~3200rpm at 3rd"
The higher the gear, the more load the turbo sees, thus the reduced rpm spool. This is a perfect example of a turbo that's just a little too big for the engine. (For your desired traits)
As Hounos said, the smallish exhaust is creating backpressure which is not helping spool.
The higher the gear, the more load the turbo sees, thus the reduced rpm spool. This is a perfect example of a turbo that's just a little too big for the engine. (For your desired traits)
As Hounos said, the smallish exhaust is creating backpressure which is not helping spool.
#6
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![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Originally Posted by OverRev
and IC piping are too big so there is too much free space for the boost to fill up b4 it goes into the cylinders.
As stated above, for a quick and dirty exhaust test, just unbolt the sucka and take it around the block for a "the neighbors hate me test."
![eek5](https://www.miataturbo.net/images/smilies/eek5.gif)
When your turbo spools earlier, quicker, and you feel that additional power at high RPM, you'll be
![](https://www.miataturbo.net/images/smilies/skid.gif)
And last, nice underhood!!!
Last edited by UofACATS; 07-02-2006 at 05:36 PM. Reason: addition
#8
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It's not really the size of the piping that is the problem, except for the 2.25" piece. Your muffler is more restrictive than it needs to be. Get a straight through muffler like a magnaflow, I have one and it doesn't sound bad or too loud at all. Haven't been running the car much though with ECU problems.
#11
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hmm, i just found out the problem with help of my frd, red90 who drives a turbo miata with simular setup as my, the reason it's laggy is very very stupid, on the ultimate there is an option for u to update ur injector size, so i set it to 305cc instead of the origianl 210cc, and the result is that the ultimate pulls the ign. timing back crazily, it's almost like 8-10 deg. lower thru-out the entire map, that's y it's laggy and not making pwr. imagine setting ur ign timing to 0 deg on the pully and dat's y it runs like sh*t.
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