My Rom Tuning Endeavors
I wanted a space where I could share my experience with rom tuning and the methods and information I have obtained during my road of getting my 240sx SR powered project on the road.
First I am going to shed some light on my project and how it all started.
I originally had a 98 Altima which I had plans on slapping a t25 turbo on, but due to the automatic I changed my mind.
So a buddy of mines had just got his 240sx ka-t out of the shop from being tuned and I had the pleasure of riding passenger seat while it was on 8psi and MY GOODNESS did this car press you up against the seat at only 8psi but it had a nice GT3076 on it so I couldn't imagine what it would feel like on more boost. So from that day I as inspired and wanted a 240sx what would be better then a rwd Altima! Of course it wasn't a Altima which was a 4 door sedan but it shared similar motors.
So fast forward a year and some change and I stumble upon a dirt cheap 240sx with a SR. It had the following:
S13 Redtop SR (stock motor)
Kaaz 2 way lsd
tein basic coilovers
Greddy FMIC kit
Megan Racing manifold
and a few other goodies
Car was missing some odds and ends that was needed to get it running but to make the story short it needed a new motor.
I had my car towed by Brandjayfabrication which is located in MD, they sourced me a new motor set among a few other things.
Work wasn't done by them due to other constraints so I had the car moved to another shop where the motor was installed, wiring for the swap done, suspension work done etc.
While there I paid a guy who comes on this forum from time to time to post to come down and tune my car. I had some issues, and since my car never made it on the road these things didn't come to light until then. Here were the problems:
TPS was bad
Car needed tension rods, front end alignment and a few other things
BOV kept sticking
So he was able to get the car running around 13 afr's at idle and the car didn't see WOT due t the alignment issues it had even at 8 lbs the car would pull hard to the right.
I had the suspension work finished at the shop and once done the car went back to running like crap and ridiculously rich. The idea and the agreement that I had with the tuner was to resolve the alignment issues and come drive up to PA to have the car re tuned on the street. I wasn't able to do that because the car went back running like crap.
So fast forward, a month or so I replace the TPS and set it at .5 volt closed and 5 volts at open. I purchase a base map from JK tuning with the idea to make a trip up to PA to have the tuner finish his work.
With the base map John sent the car still ran pig rich at idle afr's would dip down to the high 9's and low 10's. Also, at idle the car runs really rough, jerks and hesitate as if I have really large cams. I purchase the Nismotronic software along with Tunercode hoping I could create a base map for my setup which is as follows:
Stock bottom end
Cometic HG
BC 264 Cams
BC valve springs
Z32 Maf
JGY fuel top feed rail
75lb Delphi/MSD injectors
Honda Accord Resistor Box
Cast iron top mount t3/t4 manifold
Enjuku Racing t3/t4 50 trim with .63 a/r
I also have a basic board with 2 SST reflashable chips 27sf512 I believe.
I have made countless changes, no matter what I do the car runs rich.
So I pinpointed several things that I believe is wrong and in no particular order:
1. FPR has gone bad (purchased a Megan Racing Adjustable FPR)
2. MAF is no good, can verify this with sofware such as NDS or ???
3. Timing is off, once again can verify this with NDS or Nismotronic ( I have a cable but once I start the car the cable is never able to reconnect)
4. Vacuum leaks (purchased some carb cleaner plan on testing prior to megan racing FPR install)
5. Idle air speed adjustment?
Any comments and or thoughts?
First I am going to shed some light on my project and how it all started.
I originally had a 98 Altima which I had plans on slapping a t25 turbo on, but due to the automatic I changed my mind.
So a buddy of mines had just got his 240sx ka-t out of the shop from being tuned and I had the pleasure of riding passenger seat while it was on 8psi and MY GOODNESS did this car press you up against the seat at only 8psi but it had a nice GT3076 on it so I couldn't imagine what it would feel like on more boost. So from that day I as inspired and wanted a 240sx what would be better then a rwd Altima! Of course it wasn't a Altima which was a 4 door sedan but it shared similar motors.
So fast forward a year and some change and I stumble upon a dirt cheap 240sx with a SR. It had the following:
S13 Redtop SR (stock motor)
Kaaz 2 way lsd
tein basic coilovers
Greddy FMIC kit
Megan Racing manifold
and a few other goodies
Car was missing some odds and ends that was needed to get it running but to make the story short it needed a new motor.
I had my car towed by Brandjayfabrication which is located in MD, they sourced me a new motor set among a few other things.
Work wasn't done by them due to other constraints so I had the car moved to another shop where the motor was installed, wiring for the swap done, suspension work done etc.
While there I paid a guy who comes on this forum from time to time to post to come down and tune my car. I had some issues, and since my car never made it on the road these things didn't come to light until then. Here were the problems:
TPS was bad
Car needed tension rods, front end alignment and a few other things
BOV kept sticking
So he was able to get the car running around 13 afr's at idle and the car didn't see WOT due t the alignment issues it had even at 8 lbs the car would pull hard to the right.
I had the suspension work finished at the shop and once done the car went back to running like crap and ridiculously rich. The idea and the agreement that I had with the tuner was to resolve the alignment issues and come drive up to PA to have the car re tuned on the street. I wasn't able to do that because the car went back running like crap.
So fast forward, a month or so I replace the TPS and set it at .5 volt closed and 5 volts at open. I purchase a base map from JK tuning with the idea to make a trip up to PA to have the tuner finish his work.
With the base map John sent the car still ran pig rich at idle afr's would dip down to the high 9's and low 10's. Also, at idle the car runs really rough, jerks and hesitate as if I have really large cams. I purchase the Nismotronic software along with Tunercode hoping I could create a base map for my setup which is as follows:
Stock bottom end
Cometic HG
BC 264 Cams
BC valve springs
Z32 Maf
JGY fuel top feed rail
75lb Delphi/MSD injectors
Honda Accord Resistor Box
Cast iron top mount t3/t4 manifold
Enjuku Racing t3/t4 50 trim with .63 a/r
I also have a basic board with 2 SST reflashable chips 27sf512 I believe.
I have made countless changes, no matter what I do the car runs rich.
So I pinpointed several things that I believe is wrong and in no particular order:
1. FPR has gone bad (purchased a Megan Racing Adjustable FPR)
2. MAF is no good, can verify this with sofware such as NDS or ???
3. Timing is off, once again can verify this with NDS or Nismotronic ( I have a cable but once I start the car the cable is never able to reconnect)
4. Vacuum leaks (purchased some carb cleaner plan on testing prior to megan racing FPR install)
5. Idle air speed adjustment?
Any comments and or thoughts?