88Trans-am

been a while since i've posted..... just got my car back from tuning/... I bought the HSR used and hooked it up to the stock 305 computer.. I have a 350, votec heads with beehive springs comp cams 218/224 @.050 .495/.503 making power from idle-5500 RPM. MSD 6A with the MSD coil cap and rotor and stock HEI distributor....

Considering i didnt get the HSR with the stand alone system i had to get someone to tune it...... i got it back yesterday. now this combo should perform all the way too 6000 but they stopped at 4500 making 250 rwhp and 320tq@2000 rpm.. but the car backfires?????? when i stomp on the throttle it doesnt downshift but it did with the stock motor and the result is like its starving for fuel or something...it sputters. so i dont know what to do the cap and rotor is all black inside. it has 24 lb injectors... fuel pump is priming but is stock as far as i know i feel like it is not tuned right. The guy even told me this. if i put it in first gear and romp on it she hauls hard but still feel as if it could do better.the fpr is the stock holley non-adjustable. Anyone have any clue on what to do? my tuning guy says to spend the 900 on a stand alone system, but considering he put a new chip in it it would have started from scratch right???

any help would be awesome

old z mzn

iTrader: (1)

do a search. there is a enough info to do it yourself. got my tuning stuff from www.moates.net

Orr89RocZ

iTrader: (20)

Find a better tuner and get your ignition sorted out. Shouldnt be "black" on the inside. Aftermarket ECM wont help you.

Fix the spark issues, make sure you have the correct plugs for the vortec heads and gap them at .040 or so.

88Trans-am

I did not know that vortec heads required special plugs....... is this true?????? i'm wondering if it is my distributor... I re-used my stock distributor from my stock TPI motor. Upgraded my ignition and coil to MSD. i noticed when it was out of the motor that when i turned it, it would bind up at one point almost every 360 degree turn... could this be part of the issue as well?

thanks for your help boys

cIaRmOaCrZo

aside from the spark issue, you said it doesnt kick down when you romp it. and that sounds like a miss adjusted tv cable. but yeah, you need to find a better tuner for sure lol

vetteoz

iTrader: (13)

Just last week I put a HSR on a alum head L98 with ZZ4 cam and springs
Stock small cap dist and MSD coil.22lb Bosch III's
Using stock '91 SD tune on '730 ECM it started , idled and ran great.
Pulled hard to 6300 on datalog ( Done accidentally ; column shift on '56 Chev hard to move on fast shifts. )
Obviously some tweaking could be done to tune but no flat spots or knock counts showing @ WOT.
Kicked down and accelerated fine with no hesitation

Orr89RocZ

iTrader: (20)

They require different length reach than stock heads and even most aftermarket heads.

They require a .708 reach while most heads use a .750 reach plug. That may or may not be an issue with yours.

mlynch001

My 85 El Camino 310 with TPI pulls strong to 5500 with 730 ECM, AXXB Chipset, 19lb Series 3, F body Headers, Etc, etc. . My EQ Vortecs use stock reach plugs. Sounds like you need someone who is a better "tuner"! Black inside the distributor is WRONG, could be causing cross firing! You need to see what the cause of this is. It takes a TON of miles for an HEI to get a lot of build up of carbon in the cap/rotor area. That is either carbon or dirt inside the cap, but both will cause crossfire because that crap conducts electricity, ESPECIALLY 40KV that a good HEI puts out. TV Cable is likely adjusted wrong, that is a MAJOR issue and will cook the transmission if not corrected PRONTO!

88Trans-am

TV cable is adjusted properly for sure... the guys who tuned my car put springs on the throttle body because apparently the butterflies would not stay closed.... never heard of that before as it is still spring loaded and worked fine before. maybe i need to find a better tuner, but i've tried 15 different people and they all say same thing.. "the system is too old" would it be better to buy the software that had originally came with the HSR and try taking this on for myself??? i'm planning to do a 383 with vortec supercharger as my next project and keeping the HSR...opinions appreciated
Thanks