I made 360 @ 12 psi. To be honest I was hoping for a bit more. Somewere around 400. Steve kan said it was making 10 psi @3000 rpm with my GT40. I was pretty suprised that it boosted this well. Unfortunatly, My injecters seemed to maxed out (duty cycle). In 2004 I made 340hp to the wheels on stock fuel system with a pettit ECU and bolt ons. I was pushing around 15 PSI though. I thought 1200/750 cc injectors and a walboro fuel pump would be plenty of injector and pump for 400 hp. I am also running a Power FC.

I have 10 ohm ceramic resisters on each injector. There was a 11.5 ohm difference between the the stock and RC injectors. Is this the wrong way to do this? Could this be the reason for the high duty cycle, or are the side feed injectors that more efficient?

Thanks for for any help in advance,
Brandon

 

Anyone?

 

Here this might help you out

http://rx7.com/cgi-local/3rdgencalc.cgi

 

Fuel filter? I had a car that came to me with a high duty cycle. Found the fuel filter clogged.
Thanks Robert

 

I replaced the fuel filter and it seems that it did not help the duty cycle. I will do some more testing today.

Any more ideas?

Do I really need resisters when I run a low impedence injector with the power FC?

 

it's not going to change your duty cycle since this is programmed on the EMS. the only changes you would see is the a/f ratio running richer if fuel pressure was suspect due to the fuel filter.

 

you do not need resistors with the pfc... or at least thats what i am told. i bought my car with the 1680's and im in the midst of the new engine build up and i do not see any resistors on my secondary harnesses that go to the injectors. strangely thought someone told me i need resistors for my 1680's so im completely confused! someone needs to lay law on the forums to all of this riff raff...

 

My opinion is that if the car came with high impedence and you bought a ECU for your car you have to use the same type of injector but if you going to use low impedence you have to use resistor pack to ease the job of the injectors drivers.
A friend bought a PFC for a Mitsu that uses low impedence and change the injectors to high and we eliminate the resistor pack.

 

Taken from here http://rx7.com/cgi-local/3rdgencalc.cgi

Primary Injectors: 750cc
Secondary Injectors: 1200cc
ECU Controlled Max Duty Cycle: 88%

Total Flywheel HP:
518.1
Suggestions:

Seems like I should be able to squeeze some more out of these injectors?

I dont have any pressure drop at high RPMs either.

 

see whats weird is i dont really see how 750's and 1200's could handle 518 whp... i guess they figure that when your shooting for that much power you have two supra pumps keeping that line pressure up. they need to specify fuel pumps on that damn thing.

another question does anyone know how to setup the low impedence 850's on the pfc? i could use this answer.

 

You set them up exactly like the manual says which is the same as for 850 high impedance. There aren't any parameters to change to correct for impedance differences. You have to use inline resistors to prevent burning out the inj drivers when running low impendance injectors. This will affect only the lag of the inj, not it's flow rate.

Read some other posts about injectors on this forum.

 

i dont have a manual for my dl... and i only got one email back ever from glen and yari ( i think thats their names). does anyone have it hosted anywhere?

on another note i guess i will have to call keith and get info on the resistors. who knows with all the confusion on the forums here. thanks for the informative post!

 

just posting incase someone else comes across this problem. keith informed me that i do need the inline resistors for the 850's. i have not received them yet so i have not measured the resistance to determine the inline resistor size. if its above 4 ohm I need a 2 ohm and below i need a 3 + ohm resistance... is this a good rough idea?