Dahm82z28

I bought an 82z with the 305 crossfire injection. I do not really know much about this crossfire other than its performance is very poor. The acceleration is bad and very hesitant. Its sluggish to start off and then gets jumpy. I changed the fuel pump and thought it might be low pressure. This helped it a little bit but the performance is nothing to what it should be. Would a general tune up help this matter? If anyone has any ideas for a new intake that would work for me or anything to replace the crossfire injection that would be great! Any comments would be appreciated. Ive looked and talked to many people..

8t2 z-chev

does sound like there must be several things wrong...
Does the CEL work?
Fuel pressure could be wrong,even with new pump.
Vacume leaks.
Wrong ignition timing.
Engine problems(worn cam,worn timing chain,burnt
valve,etc.)
Leaky EGR valve.
Lots of posibilitys...
CFI can run good and strong with perfect reliability
CFI can be replaced with a carb setup pretty easy,
when i had my CFI off my car in order to perform
performance modifications to the manifold and other
parts,i just clapped a 4-barrel manifold,q-jet,non-ccc
HEI on,tuned it and ran it untill i was ready to reinstall
the CFI system.Had it running great with the q-jet,
but it only got about 15MPG-with the modified CFI
back on,get about 20MPG,runs even better and very
little trouble in over 15yrs

Dahm82z28

Thanks for the info it all sounds like it could be the source of the problem.. any ideas of where to start first to kind of narrow it down possibly. i am young and dont work on cars much but i know plenty of people that do. so any information that i can relay to them would be great. thanks!

Dahm82z28

what kind of mods to the CFI did you do?

8t2 z-chev

first step is to get the CEL or "check engine"light
working if it does not work now-it should light when
the ignition is turned on and go out after a few sec.
if no problems are detected.
Any major sensor or major false inputs to a sensor
will be stored as a trouble code in the ECM that can be
retrieved and provide clues to the problem
The engine in my car is an'84 vette 350 with CFI,
most of the modifications involved the intake manifold
runners-welded extra aluminum to the entery of the
runners,then used a die grinder to enlarge the runners
and create a "flared"shape to the runner intakes.
For more clearance above the enlarged runners,a 1/4"
spacer was made to raise the upper plate.
In addition,the stock heads were given a mild port
job-all this resulted in a big power increase over stock
'vette,at least 1500 more usable RPM,even low-end
torque seemed to increase