I am looking into fuel systems. I am pretty happy withthe research I have done to this point up to the injectors. I have a GZ LIM and am looking to use 4- 16000's oin the secondaries and high impedance 750 bosch injectors in the primaries. This is more fuel than I will need right now but I will need it in the future. I really like the quality of the CJ motorsports fuel rails but they only use top feed primaries. My question is:

Is there any difficulty with getting the top feeds to idle correctly?
Is there any difficulty with part throttle driveability??
If I choose to run 6 injectors- will there be an atomization problem because I will have a 750/1600 cc feeding one runner and a 1600 feeding the other?

Thanks for your input,
John

 

First off, what bosch high imp. 750's are they?

There is absolutely no problem in using top feed injectors in general.. As far as idle and driveability goes, that depends more on the injectors themselves and if they are properly setup and tuned. Most injectors in that flow range tend to have poor atomization which hurts idle and driveability, but we are currently working on a solution to that problem...

 

They are approximately 750cc, I am not sure exactly what the art number is. What primary would you suggest using?
John

 

I've got Denso 720 (probably flows more than that, Denso injectors tend to be underrated) low impedence topfeed injectors in my FC as primary's and I don't have any issues. This is using the stock FC primary rail (FC's had topfeed injectors stock), and then I have a KG secondary rail with Bosch 1680's. I seem to have a lot less problems than guys with 850's do, at least on a Power FC. 850's tend to idle pretty rich and need some work to run decently on the PFC. I can get my 720's to idle at 13:1 AFR (although my car likes to idle richer than that for better idle stability).