I have a 95 z28. It is .030 over,p/p stock valve heads, port matched intake, 52 mm t-body, accell 30# injectors, comp cam: 224/230duration 112 lobe seperation 503/510 lift. Iam running 43 lbs fuel pressure, and tuning with lt1 edit. Please help!!!

 

Well I had a hesitation problem around the same rpm and it turned out to be the optispark. It's basically a distributor, so it wears out just like it does in every other car without coil packs. I have also heard of guys having a miss at a certain rpm range when they are using an aftermarket ignition system. Just a couple ideas I thought I would throw out there for ya'.

 

Thanks for the reply. I will try the opti spark and see how it does.

 

I was actually misfiring at high RPMs for a while. Mine was just fouled plugs from bad knock retard. plugs are cheaper than a new opti!

 

Simple question before you go ripping apart your combo. Have you checked fuel psi to see if it drops as vaccum increases? A bad fuel pump would cause a high end stumble. Clogged fuel filter?

Go over everything easy(ier) before you do the opti. Check fuses, intake leak, vaccum leak behind the MAF, plugs, wires, make sure the boots are all the way in the opti. Maybe you have a batch of bad gas?

Let us know your progress.

 

hey

how do you like your cam? i was planning on running it too

do you have any track times or dyno #s? and head flow #s to go along with them? thanks

 

I am really starting to like the cam. It has a great sound to it. I have no dyno or head flow #'s, but tonight I went a 7.99 1/8 mile with a 1.64 60ft at 86mph. This is with a TH350 trans, TCI super street fighter converter(It goes 3100 on foot brake with sticky tires), and stock 3.23 gears. My car is a 355, 30# injectors, 1.6 rockers, 52mm throttle body, zero deck block(9.5:1 pistons), p/p stock valve heads, p/p intake, tuning with LT1 Edit. Personally I believe I have mad a good choice. The car went a 7.41 on a 125hp shot.