i hope they give you some money off when they out in the new eprom program.i have had my doubts with the 96 ecu working in the 99 correctly thats why i have held off.maybe if they get it all figured out i might send in my 96 ecu for the upgrade.

 

You should get yourself an adjustable fuel pressure regulator. That way you can just adjust your FP to get the AFR you want. When I installed my JWT ECU, my se-r ran super lean with the new header. After adjusting my FP I got it back to mid 12's up top (I have a wideband). It is alot easier to just mess with a FPR than to wait for the ecu to get new fuel maps.

I know for a fact that when my se-r ran as lean as yours did with the JWT ecu, its not going to be making the power it should. You'd be surprised how the same program would cause one car to run lean vs another to run just right. If I'm not mistaken you should get your car datalogged so we can see your STFT and LTFT (short/long term fuel trims).

 

sounds like a good idea. i know that my mevi would cause my maxima to run alot more rich at WOT thans the usim

 

I am going to answer a couple things in this post concerning Chuckies and nismo87se post.
Jim Wolf himself called me on thursday to discuss what was going on with my cars and the dyno results.
Basically 2 things were discussed on some runs my MEVI would not open or stay open on some runs as a result of a bad check Valve which i have since replaced. The second thing is the very LEAN a/f condition i was experiencing in the upper RPMS. According to him i am the first guy to actually send in a dyno showing what is going when the MEVI comes on and although he did no admit it i believe they were never tuning with the MEVI in mind that is why once it opens the added a/f causes such a lean condition which would result in the car pulling timing. If my car were still using the stock intake manifold this would never have happened. I am not going to get a APR because they are writing me a new eprom specific to my car with MEVI so it should have correct a/f ratios.
All the JWT ECU/MEVI intake dynos i have examined have this same condition which is why people are still experiencing gains when they tune with an SAFC.
Chuckie the ECU works its just 1999's are diffrent animals and 1999 calispecs are even more diffrent.
I believe and this is pure speculation. That 1999 calispec cars may have a more agressive tune to compensate for additional pre-cats and swirl valves as well as other emissions related stuff. This way the car would retain the 190hp/205tq that it was rated at.
I am sending out for the new eprom which is specific to my car and i will re dyno once it is installed.

 

NO at this time i am no longer considering the SAFC since the new eprom should be written using the af on my dynos.
I have reinstalled the stock ecu since the dyno and have been driving around with that one installed because i am concerned about the really lean condition up in the higher rpms.
run 32 and 34 were done with 3 minutes of each other which was how long it took me to switch the ecus.

 

sounds good. but im no longer using the mevi.just want the upgrade for more power. im doing a 3.5 swap next year.so im putting no more money in this engine besides the ecu upgrade

 

Here is another thing I noticed, sometimes the dyno's AFR (tail pipe version) would show a different reading than my wideband (2nd bung added near o2 sensor). Also this is why you should get some datalogs done too, if I'm not mistaken on JWT's website how to configure CONSULT for logging. If you didn't have consult but some other OBD-II reader, you could log MAF lb/min, rpm, ign timing, TPS %, coolant temp, o2 voltage and STFT/LTFT. I still say that bumping the fuel pressure about 3-6psi probably would've made the same difference as getting new fuel maps, however it would be quicker/easier.

 

Keep us updated Zack. If the JWT ECU is giving out gains like what you posted, I'd rather get mine from somewhere else.

Hopefully it's just a bug that they need to work out.

 

ECU will be here tomorrow with new program

 

Well get back to that dyno soon so we can see if it has benefited you.

 

So.... what's up Zack? Have you had any time to dyno your Max yet? I'm pretty sure everyone's just as curious as I am to see if JWT turned out good or not....

 

money is tight rightnow just spent $650 on new clutch with install.