88Trans-am

hey guys.... i finished my build last year and had a local guy do my tuning.... its an auto 700-R4 with a b&m shift improver kit. Now,on the dyno he put it in thrid gear and then as he proceeded with accelerating it had an intermittent misfire. WHY lol keep in mind it has an MSD ignition and coild, street fire wires and some cheap champion plugs. when i drive it in overdirve it doesnt downshift when i hammer on it unless i maunually shift it down a gear and thats when it happens... as soon as i throw load to it. thats not right . I bought some ngk trr plugs today but have to wait till spring as its snowy here, so i'm looking at all the possibilites for before the nice weather... The dizzy is pretty rusty inside so i'm going to but a new one anyway but i dont know if its the trans also. any ifo would be appreciated guys.
Thanks

88Trans-am

oh ya ... there is nothing wrong with the timing either.

Cosmik Debris

Misfire under load can be attributed to spark weakness, plugs, leads, distributer contacts etc. I'd start with plugs. As for the tranny problem, read up about B&M kits, maybe this is a common problem.

88Trans-am

ya after i installed the b7m kit is when i read that it is not a good kit to intall... i got new plugs, i know the wires are good but the rust and moisture under the cap in the dizzy cant be a good thing either.
thanks for the reply

ex-x-fire

Grab the rotor & wiggle it, if it has any slop then the distibutor is worn out. This can cause a wondering wierd misfire.