Honda D Series Forum banner
1 - 3 of 3 Posts

90 Posts
Discussion Starter · #1 ·
Hey guys im back and ready to tune the car now. for those who don't know the set up here it is:


Turbonetic Turbo
Turbosmart wastegate
Vortech Blow off
Vortech FMU
Precision Turbo & Engine Front Mount Intercooler
Crane Hi6 Ignition
Magnaflow Cat-back exhaust
AEM Fuel Pressure regualtor

Anyhow i've spoken to a local guy who come highly recommeded for street tuning with Crome. I understand from all the feedback that i need to replace the FMU and get a better management system. Can I stick with a Chipped P28 street tuned with Crome and still retain my stock injectors and fuel pump? Im running about 6psi of boost. Or is it HIGHLY recomened that I get the injectors at the same time? And last do i need a better fuel pump? Or do i have to replace that to? thanks Any other input, suggestions is appreciated.

93 Legend L Coupe.
11,404 Posts
Probably not, but you really should get larger injectors. The problem with switching from a FMU to a chipped is the fuel pressure. The only reason why your engine survives with the FMU is a increase in fuel pressure forces more fuel out of the injector. With the chipped ECU, you alter your injectors duty cycle (how long they are open). The 240cc injectors that are in your engine now simply won't flow enough at stock fuel pressures to accomodate 6PSI. You can combine an adjustable FPR and use it in conjunction with a wideband to tune your setup, but it is recomended that you upgrade your fuel pump with any serious FPR. If you simply find some DSM 450cc injectors, you can run any boost you could want with most turbos with your stock MAP sensor. It is inexpensive isnurance, as used DSMs are less than the cost of rebuilding your engine, or having to buy a new one.

Lifetime Awesome Member
'89 CRX HF
25,544 Posts
honestly, you are going to need bigger injectors. stockers run out at around 170whp. and thats at 100% duty cycle, which you dont want to be running all the time.

search online for a set of DSM 450s, you can usually get them for about $50
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.