Am I still going to need a FMU if I get larger injectors? If not is it good to run one anyway?

What's your guys' suggestion on a FMU? Yeah, I know you've all heard it before, but what is a reletively cheap one? I'm trying tp piece this kit together for under $1500, and I have, just the FMU might bump it over the top.

thanks guys,

cartech fmu.. heard good stuff about them.

i think you're gonna run CRAZY rich at idle.. it'll smoke and run like hell. get a low rate FMU.. i think you're gonna need some sort of injector control.

I am doing engine tuning, but I'm doing a cheaper more unconvential form DIY of tuning, EPROM tuning. It's exactly what JWT does, but I'm doing it myself, it's cheap too So the map is going to be changed for the larger injectors and I have a full OEM map that I can play with at the dyno.

Which setup are you using for EPROM tuning? I am VERY interested in this, please post info!

If your doing a rom tune for larger injectors you won't need a FMU. You should be able to have the injector duty cycle cover all of your fuel needs. Just make sure you have a high volume fuel pump.

WD

Thanks WDRacing, that's what I needed to know. Also the pump is very high on my list, I know what needs to be done as far as engines that already come turboed, it's the ones that don't have one like the KA that I'm trying to figure out. I'm thinking of running a KA-T while I learn how to do some engine tuning, and do some other things to my car, and it'll teach me to weld, etc...so it's a big learning experience for me. Then I can put all the knowledge over to a CA18DET, which is what I was going to do in the first place, but I sat down and looked at how much a KA-T would cost me at 7psi, I came up with about $1500, if I make alot of the stuff myself, and get friends in Japan to get me a turbo.

EPROM Tuning: http://www.boostcruising.com/silvia/epr ... ..htmlalso, check out http://www.wanganmidnight.com, go to their forums, then go to Tech, there's a large EPROM section there,

WDRacing wrote:If your doing a rom tune for larger injectors you won't need a FMU. You should be able to have the injector duty cycle cover all of your fuel needs. Just make sure you have a high volume fuel pump.

WD

guys have run beyond 10psi on the stock pump... so it really depends on the amount of wear and tear on the fuel pump and the condition it's in. I ran 7psi on my car with the stock pump and 370cc injectors and didn't have a problem leaning out untill beyond 8psi.

I'd like to not take my chances, so a 300zxTT or Walbro unit is gonna go in,

AceInhole wrote:guys have run beyond 10psi on the stock pump... so it really depends on the amount of wear and tear on the fuel pump and the condition it's in. I ran 7psi on my car with the stock pump and 370cc injectors and didn't have a problem leaning out untill beyond 8psi.

Yeah, but when your pump starts to go out, you lean out all of your cylinders and blow your whole motor. At just over 100 bucks you can't afford not to swap out the pump.

WD