85 VETTE PRO COMP ALUMINIUM HEADS 68 CC 202\1.6 VALVES COMP ROLLER CAM AND ROCKERS 488\496 260 DURATION, FACTORY TPI SYSTEM UPRADED WITH ADJUSTABLE FUEL PRESSURE REGULATOR AND LARGER INTAKE RUNNERS, THROTTEL BODY ALSO LOOKS NEWER, WAS ON CAR WHEN I BOUGHT IT, BUT HAVE NO IDEA IF ITS STOCK, HYPER CHIP INSTALLED RUNS TO LEAN ON CURRENT SET UP BL IS 160 SUGGESTIONS WHOULD BE GREATLY APPRICEATED.

 

Get rid of the Hyperjunk chip and use 22# FI set AFPR at 45psi. Should Idle at 36/40 psi.

 

man if your gonna be changing just get 30lbs'ers and a custom tune...because unless you get a custom tune your computer will think its running stock size injectors, messing with fuel pressure will somewhat work but it'll never be right....and i agree get rid of the hypercrap!!!!

 

Bigger is not always the best way to go. 30# fi are overkill for what mods are on that engine.
The Max would be 24 # fi and a new Chip will be required.

 

thank for info, the injectors are yellow and look new, also already on car when purchased, i supose i should pull one and see if i can find a part # and find out what it is, im guessing stock 22lb, any way it seems that car should not be this lean, and i can get it to run rich at wot, so seems injectors could be okay , except, i think its probably being retarded by knock sensor which could explain richer signal, what are your thoughts on BL # at 160? lean overall? should this set up run okay on stock injectors? i get the message about the hyper crap, what should i do go back to stock prom? where can i get a prom for this set up? i really dont want to get into custom burning right now just want to get running well enough to cruise in for now, and get some break in miles logged. i was having problems with o2 circuit so i hooked up afr seperatly and still showed lean for some reason o2 circuit shows 1.2 mv key on engine off normal key off like something is back feeding, scanner shows 459mv had to hook up multimeter to get true readings. after engine warms up and is in closed loop scanner and multimeter show same values. also match afr gauge hooked up seperatly. once warm runs better but at 150/200mv 160 BL can hear air leak at plenum gasket probably explains high idle 1400rpm when warm, grounded o2 sensor body to battery term with jumper still 1200mv when cold back fed out of ecm. unplug sensor and check coming out of sensor only 20/40mv [normal] out of ecm to o2 1200mv WTF! tried another ecm same thing. but again everthing normal when at temp in closed loop i can hook up scanner, afr and multimeter all whithin 50mv of each other. could IAC back feed onto o2 circuit, and then when warm IAC volts way down not affecting? any way going to take some old fashion plug readings, see what they can telll me used laser therm on exhaust manifolds never saw temps over 700 usally 450 to 600 got as low as 350 at one point, these readings were all taken at idle after running for several minutes, while adjusting fpr looking for improvments 42-55 psi very little change to actual o2 sensor readings taken with multimeter, not scanner dido for afr. yeah im scatchin my head, seems to be a wealth of knowledge on this site, hopfully some of you guys that live, eat, and sleep TPI can get me straight, thanks!

 

when you put that much pressure on an injector and there is no change it is definately time for bigger injectors...personally 24's would be a waste of time just for the simple fact that much more of a cam would most likely max them out....im in vote for the 30's because you can tune for them and they will support a decent amount of HP without haveing to worry about maxing them out.... i run 30's with no problem at all....just gotta find someone who knows what they are doing when it comes to tuning

 

If you can get the number off of the injector I can tell you exactly what size they are.
www.southbayfuelinjectors.com

 

I am assuming that you have a 355ci and if thats true then I will second the 30lbers. I am in the process of building a 355 for my 85 Iroc but on my 89 5.0 mustang I have 30 lbers on a 331 stroker and it runs ***** w/afr 185s and holly fuel injection intake, full length headers, 560 lift and 230 dur at .o50. It does run a bit rich at idle but thats because I haven't gotten a chip burned for it yet so i would recommend doing that. If you don't and you idle for extended periods of time ( like way more than just normal stop lights and engine warm ups, I am talking like more than 20 min of just idling) it can wash out the cylinders and thats not good. If that helps any.