1991 RS From what I have read the proper fuel pressure for the stock 305 tbi is 13psi. I have swapped a 350 bored .30 over, mild cam, headers, and the 68# cop car injectors. I also swapped the ecm out of the donor car which was a 92 caprice police car. I have a new E3268 Higher than stock volume fuel pump that I will be installing this fall.

Down to my question....Should the fuel pressure be higher than 13psi for my application or will 13psi be adequate with the higher volume pump. What would be a good fuel pressure. Also, how do I check the fuel pressure.

Thanks in advance for any help
Jono

 

This recent post may bring you a step further.

https://www.thirdgen.org/forums/post...080-post7.html

 

Read that and many other threads, still confused. Thanks.

 

All LO3 I have mesured the FP were 11.5 psi (18-20 jears old).

LO5 with 68 lbs injectors + 12 psi supports around 250hp. So 12-13 psi may be anough for a stock police car. If the donor car had VRFPR, then FP was higher then 13psi.

You have done some nice moods to the engine, best now is to adapt the fueling.

Need to do some datalogs by progressively adding more trottle and observe %DC (dutycicle). Add fuel untill %DC stays under 85% and adjust the fueling # in the chip. Best and quickest is to upgrade to EBL flash for the tuning, no more chips, make changes in the bin, load and try it out.

Once you are ready to tune it, dont worry there are many experts that will chime in.

To mesure FP you need a inline adapter to plug the gauge, like in the post.

 

Thank you!!

 

This may he a useful tool

http://www.users.bigpond.net.au/ben_...ctorsizing.xls