Well it didnt go too well. at first i was only getting 5lbs of boost. Turned out my belt was really loose so i tightened it up. after that we started to see more boost (8lbs) but didnt take it to redline. It seemed like my injectors were maxing out. Does that seem right? last time i got tuned with 10lbs my AF ratio was good, but this time i run lean after 7500rpms. I am running the stock injectors still. the only thing that has changed since my last tune is the compression was lowered to 10.5:1 and i added a test pipe. My tuner suggested that i get bigger injectors 750cc, which i plan to, a 3.5 map sensor, which i plan to, but he aslo said that i should get a fuel rail and an AEM injector driver. Are the last two really necessary? my current set up- CTSC non AC, AEM EMS 10lbs pulley (according to my last tune a year ago) sleeved block, forged 10.5:1 pistons

 

Check the fuel pressure. Fuel pump may be the culprit. I re-read the post and you start running out of injector about 300-320 rwhp. What kind of power where you making?

 

I thought anything above 8psi or so, you'll need larger injectors.


btw what whp/tq did you get?

 

Thats what i thought too. i did change it about a year and 2 months ago, but then it sat for a year. is it possible it may have gone bad from not running for so long? I realy dont think that 10lbs of boost would make the stock injectors max out. I only hit about 270rwhp with a bad AF ratio

 

I got mine tuned a couple weeks ago with a 8psi pulley and got 322whp/211tq(dynojet).tuned with an Emanaga ultimate.btw i have a VortaK.

 

But last year i hit 330rwhp with 10lbs of boost and a good AF ratio. it was tuned by Shawn church's shop. This time i went closer to my town at Revd up customs. I have no clue whats going on, but i am leaning towards another bad fuel pump

 

right now i have the comptech fpr, should i change it back to the stock? or should i get a different one? how can i check for fuel pressure? what should it be at?

 

These are not necessary for your setup. The stock fuel rail will support more hp than your blower can puff out. Injector drivers are typically used with 1000cc and larger injectors. Again not needed for your setup. If you're shooting for 10 or 10.5 psi the stock map sensor works fine. Want to go higher than 10.5psi? Save yourself a few bucks and get the GM 3 bar map sensor.

A band aid for your situation would be to run higher fuel pressue via an AEM adj FPR, but it's not recommended.

Do it right. Get some 750cc injectors, tighten that belt, and rev her up past 9k.

 

The easiest way to check for fuel pressure and to set it is by using a fuel rail tapped with a pressure gauge. I have one for sale if you are interested.

Mine is set at 49psi at idle with the vacuum hose off the fpr.

 

I am running 550cc rc injectors at 50 psi static fuel pressure. My car pulled 360whp without fueling issues. 8psi

J