I have a 98. And I was wondering when running the V2 with a 10 pound pully would I need to put in higher flowing injectors? I am asking this because JWT does not make an ecu for my year max...so I am wondering if it would be pointless to put in higher flowing injectors with out an ecu upgrade any info would be helpful. Thanks.
Carson

 

There are a couple of good reasons for installing bigger injectors. The main reason to do it is to lower the fuel pressure needed for adequate fuel supply. Lower fuel pressure results in less danger of injector lockup, and also allows the fuel pump to provide maximum flow (full flow capacity characteristically decreases with increasing fuel pressure). If you also change to a Z32 maf, you also benefit from reduced injector duty cycle as well.

There are a couple of ways you can run larger injectors with the oem ecu. I'll describe two that I have had experience with.

1. 370 cc/min injectors, A32 maf. In this scenario you lower the base fuel pressure to about 27 psi to compensate for the increased flow. This should be good for about 350 engine hp, or about 290 hp at the wheels, but I reccommend using an SAFC to provide extra richness at WOT and high rpm. If you are above 290 fwhp, then you can also use an fmu to provide additional fuel at higher boost levels. Several people here do this.

2. 370 cc/min injectors, Z32 maf. The increase in injector size over oem injectors almost matches the increase in flow measuring capacity of the Z32 maf over the A32 maf. Using the two together results in a system that works well at oem fuel pressure and with the oem ecu, although I experienced some pinging at high boost, so you will want to do additional tuning with an SAFC or adjustable fmu. I believe the pinging was due to timing and not to afr, since my EGT was not high. A better solution would be to retard timing based on boost pressure with a J&S Safeguard.

 

I doubt you need bigger injectors, but I did them because I figured they couldn't hurt.

I have a 99 with a V2 and 11psi of boost, and I installed 370cc Z32 injectors with the stock ECU. I used a SARD FPR to lower the base fuel pressure to 25ish psi, and a 3:1 FMU disc. I have a S-AFC for fine tuning, but haven't gotten to a dyno yet.

No problems at all.

 

ok I will be able to use search in a few days but for now I have to ask another dumb question....the 370cc injectors come off a turbo Z right? And what do those MAF's come off of? I have a friend that has put a LT-1 in his Z so he has all the stock engine stuff...I was hoping maybe that stuff would work but his is N/A

 

The injectors are only from a 95-96 TT Z. The MAF can come from any Z32 IIRC (Steve would know better).

 

ok...and the Z32 is the 90's Z right?

also...the kit I have came with a MAF on it...I am wondering what the part number is for the Z32 (or some other indication) so I will know which MAF it came with. Thanks

and isnt the A32 MAF just the stock MAF that my 98 comes with

 

Yes.

Yes.

 

The first option sounds better to me for the fact, it looks like it would be cheaper and and you run in to less problems...but on the other hand how much more power would be yielded by the second set up?

 

It won't give you more power per se - that is determined by how much air and fuel your engine can ingest. But since the Z32 maf can meter up to ~520 hp of air, it allows you to operate in in an airflow referenced system (without the need for an fmu) at higher power levels than what you could with the A32 maf.