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- Jan 28, 2004
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All sifu here, pls kindly give some light here ....i am kinda out of idea
My friend is driving a 4G15 carby Wira converted to
- 4G92P SOHC block
- GSR Intake Manifold and VR-4 TB
- 4G93P head, 4G93's 455 MAF with 210cc injectors
- 4G91 ECU + Wiring
- 4G15 carby cable gearbox
This rojak mixing was done many years back when he was still dunno anything about car mod ...
Now he always complaint to me his car is not powerful enough (compare with a original 4G9x DOHC engine car)
First Try, he was not able to rev beyond 6000RPM. He was told by some mech due to cam pulley marking was "1/2 teeth" incorrect in his 4G93 head's pulley. So during his recent timing belt replacement he swap both cam pulley taken from a 4G91 head (we counted the teeth is the same just the top center marking is different). Upon done now his car can rev upto 6500 RPM, than we found his rev cut was at 6500RPM due to 4G91 ECU limitation
Second Try , i tried swap his 4G91 ECU (code 5560) to a SGTi Rechip (code 0450 with revcut at 8200 or 9000 RPM), than we test drive the car found power delivery was just "smooth", no pickup and top end...idling all is ok, no misfiring anything...
Third Try , we narrow down and though was due to the 210cc injector limitation from 4G91. So we went and seek out for a set of 4G93's 240cc injectors.
- First test drive was with the rechipped SGTi ECU, result was same where power delivery was just "smooth", no pickup and top end but revcut improve to beyond 7000RPM (he is using 8000 RPM Wira 1.5 meter and it does touches 8000RPM but we let to throttle, scare engine kaboom.
- Then we test by putting back his original 4G91 ECU, power respond was greater thenFirst Try and revcut was at around 6800-6900 RPM now
BUT then he is still not sactisfy with the power....i even test drive his car in highway...power of DOHC is like coming too slow or not there (compare to a original stock 4G93, DOHC will "open" after 3000-4000RPM)....in his car, this feeling is not found and yet top end is so so only....we did try pushing each gear to max rev RPM especially at first 3 gears.
Is this due to tuning ?? Is this due to the ECU wiring of 4G91 ? What different between 4G91 and others 4G9x engine wiring ?? What can we do to release the power of DOHC ?
PS : we are not looking into putting performance part like regrinded cam, P & P, adjustable pulley and etc to improve performance.
Appreciate input from all the sifu....
My friend is driving a 4G15 carby Wira converted to
- 4G92P SOHC block
- GSR Intake Manifold and VR-4 TB
- 4G93P head, 4G93's 455 MAF with 210cc injectors
- 4G91 ECU + Wiring
- 4G15 carby cable gearbox
This rojak mixing was done many years back when he was still dunno anything about car mod ...
Now he always complaint to me his car is not powerful enough (compare with a original 4G9x DOHC engine car)
First Try, he was not able to rev beyond 6000RPM. He was told by some mech due to cam pulley marking was "1/2 teeth" incorrect in his 4G93 head's pulley. So during his recent timing belt replacement he swap both cam pulley taken from a 4G91 head (we counted the teeth is the same just the top center marking is different). Upon done now his car can rev upto 6500 RPM, than we found his rev cut was at 6500RPM due to 4G91 ECU limitation
Second Try , i tried swap his 4G91 ECU (code 5560) to a SGTi Rechip (code 0450 with revcut at 8200 or 9000 RPM), than we test drive the car found power delivery was just "smooth", no pickup and top end...idling all is ok, no misfiring anything...
Third Try , we narrow down and though was due to the 210cc injector limitation from 4G91. So we went and seek out for a set of 4G93's 240cc injectors.
- First test drive was with the rechipped SGTi ECU, result was same where power delivery was just "smooth", no pickup and top end but revcut improve to beyond 7000RPM (he is using 8000 RPM Wira 1.5 meter and it does touches 8000RPM but we let to throttle, scare engine kaboom.
- Then we test by putting back his original 4G91 ECU, power respond was greater thenFirst Try and revcut was at around 6800-6900 RPM now
BUT then he is still not sactisfy with the power....i even test drive his car in highway...power of DOHC is like coming too slow or not there (compare to a original stock 4G93, DOHC will "open" after 3000-4000RPM)....in his car, this feeling is not found and yet top end is so so only....we did try pushing each gear to max rev RPM especially at first 3 gears.
Is this due to tuning ?? Is this due to the ECU wiring of 4G91 ? What different between 4G91 and others 4G9x engine wiring ?? What can we do to release the power of DOHC ?
PS : we are not looking into putting performance part like regrinded cam, P & P, adjustable pulley and etc to improve performance.
Appreciate input from all the sifu....
