What fuel Injector size?

[porschelou]

Trying to get our rebuilt b34 dialed in for track duty. We have done some mod's to the engine so we want to maximize the performance gains we are hoping to get. Can anyone out there with similar mods tell me what they are using for fuel delivery (using stock e30 pumps - fairly new)? (car is a 86 e30). Fuel pressure measured 39lbs at idle and 45lbs 3500rpm

Here are our mod's:
-b34 engine
-b35 cam
- 3 angle valve job
- Ported Head / Intake
- Polished all intake ports
- 2.5" exhaust - very small glass pack - sometimes we run no muffler
- new rings/bearings

I have the following injectors laying around:
- mustang 19lbs
- Stock b34
- set of higher lb units for a turbo motor I'm building - can't remember the size right now but >19lbs - we put those in tonight and it idled like crap and ran very rich

I have heard you can run a fuel pressure reg from a porsche 944 since it has a higher rail pressure rating > 3bar.

Any inputs out there? We will take the car to the dyno in a few weeks to verify Hp and A/F.

I also have two ecu's - one stock and one with a ebay special chip

[yert315]

The engine work done does not require much larger injectors, if at all. The mustang injectors should suit you well. What engine management are you running? Power is in the tuning.

[porschelou]

Just running the stock e28 ecu / harness - nothing fancy. I have been looking at the War Chip and MAF. Looks like that will give you full capability for tuning. I think you are correct - the mustang injectors seem to make it run better. Until we get on the dyno I really have no idea. I'm going to auto-x the car this weekend. Good place to break in the motor :)

[Doughnut]

Stock injectors will be fine.

[porschelou]

Thanks for the feedback.