Camaro Jearmy

OK, got a 97 z.... cam, heads p/p intake port matched, pro charger with 5psi pulley. The car has cut out since i got it at 5200 +. It cuts out like you hit the rev limiter. I have a msd 6al box and a 6400 chip in it. I thought it was a fuel problem, put it on a chasis dyno today and afr looked great. So must be something in the ignition...? Anyone had anything like this before. Car made 483hp 443tq ... with it cutting out. The graph looks just like it hit the rev limiter, then it comes back and cuts out again and comes back then hits the actual rev limiter at 6400. I need to get this fixed. I think it might hit 500 with it fixed...

95zpro

I'm thinking it's the opti; been known to cause misses at high rpm...

Camaro Jearmy

thats what im leaning towards. is it worth the extra money to buy an msd one?

lt170chevelle

iTrader: (2)

if you are going to throw new parts at it start with plugs wires or the coil. optis arent cheap. i had a very similar problem and my aftermarket coil took a dump.i ended up picking up an msd coil from autozone for 45ish bucks and fixed it.might try that

94dragbird

iTrader: (6)

Haven't heard to much positive feedback. Most people use a GM one and mod it.

Camaro Jearmy

So if i replace it with a gm one ...what do i need to do to mod it?

This thing shuts off at 5200 like someone pulled the coil wire off, i mean its crazy. Then comes right back and does it again all the way to 6400 when it hits my chip in the msd box.

Jditlfm

iTrader: (26)

they locktight the rotor screws. and I would start with plug wires.

4SFEDZ

iTrader: (6)

mine did something similar and it was the coil! do the cheap/easy stuff first!

Jon@BruteSpeed

iTrader: (3)

What are your plugs gapped at?? Anything much more than .035 and it will do the same thing....blows the flame out.

Camaro Jearmy

already has msd wires on . Sounds like i'll change the coil first. dont know on the plug gap, i just well change them too if im going to have them out. if i replace the coil, go with msd? or ac delco, or gm?

Jon@BruteSpeed

iTrader: (3)

I have had an MSD coil on mine for the past 6 years and haven't had a problem. And we use NGK TR6's for plugs on about all the supercharger builds. If you have to replace the OPTI, use GM. Jon

Camaro Jearmy

sounds good, thanks, i'll try the msd coil first.

engineermike

I'm the 3rd to post in this thread that I had a bad coil that caused a problem identical to that.

Furthermore, I like my MSD cap and rotor much better than stock because they fixed the rotor problem, plus added a screw to seal them from moisture better.

LT1_Fireman

iTrader: (12)

change the coil and pull the plugs and gap them to .032 ...sound like spark blowout to me.

4SFEDZ

iTrader: (6)

msd coil for sure! and my ngk tr6's are gapped at .030!