All MSD experts inside please...
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Supreme Member
iTrader: (1)
Joined: Jul 1999
Posts: 1,334
Likes: 1
From: Key West, Florida!
Car: 89RSconvtZZ4TPI
Engine: ZZ4TPI
Transmission: 700R4 TRIPP TRANNY
All MSD experts inside please...
Well, after getting my MSD6AL back and repaired, I still have problems. When the car is cold, it runs like a pig with the MSD box hooked up. Stutters, black smoke (unburned gas).
If I disconnect, all problems vanish. When the car warms up, the symptoms diminish, but it still stutters under high rpm load. It's like the added juice of the MSD is overloading some component of my ignition system. New Wells Hi-Po cap and rotor, new A/C delco ignition module, new Taylor 8mm wires, new A/C delco plugs gapped at .050 (per MSD recommendation, and they work fine with just the stock HEI).
Plus I have my 92 Z28 distributor in the ZZ4TPI vice the stock, 198,000 mile distributor which is on my 92 Z28 with no problems.
It's like voltage is going somewhere and grounding out, or getting mixed up inside the cap.
I tried the MSD suggested trick of drilling a few small holes in the cap to let any ionized air out of the cap thus preventing cross fire. I am pulling ground from the fire wall for the MSD box. SHould I pull ground from a better location?
The car runs much stronger with the MSD box (when it's not acting up) plus I have the MSD timing controller mounted and ready to be hooked up once I get the box figured out.
I've run my autoxray and the only thing odd is when the car stutters, the timing advance drops from like 25 to 35 degrees advanced, to 19 deg. I have picked up no knock timing retard, just a few knock counts on start up. Could this be a knock sensor problem?
This is a ZZ4TPI MAP car. New O2 sensor, TPS is set to .56.
Thanks.
------------------
Rob P
89RSconvtZZ4TPI Edelbrock Intake
SLP Dual Cold Air Intake 1 5/8" Headers Semi-Siamesed Runners, IROC
suspension, alum shaft. Numerous mods.
92Z28convt5spd (stock)
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
If I disconnect, all problems vanish. When the car warms up, the symptoms diminish, but it still stutters under high rpm load. It's like the added juice of the MSD is overloading some component of my ignition system. New Wells Hi-Po cap and rotor, new A/C delco ignition module, new Taylor 8mm wires, new A/C delco plugs gapped at .050 (per MSD recommendation, and they work fine with just the stock HEI).
Plus I have my 92 Z28 distributor in the ZZ4TPI vice the stock, 198,000 mile distributor which is on my 92 Z28 with no problems.
It's like voltage is going somewhere and grounding out, or getting mixed up inside the cap.
I tried the MSD suggested trick of drilling a few small holes in the cap to let any ionized air out of the cap thus preventing cross fire. I am pulling ground from the fire wall for the MSD box. SHould I pull ground from a better location?
The car runs much stronger with the MSD box (when it's not acting up) plus I have the MSD timing controller mounted and ready to be hooked up once I get the box figured out.
I've run my autoxray and the only thing odd is when the car stutters, the timing advance drops from like 25 to 35 degrees advanced, to 19 deg. I have picked up no knock timing retard, just a few knock counts on start up. Could this be a knock sensor problem?
This is a ZZ4TPI MAP car. New O2 sensor, TPS is set to .56.
Thanks.
------------------
Rob P
89RSconvtZZ4TPI Edelbrock Intake
SLP Dual Cold Air Intake 1 5/8" Headers Semi-Siamesed Runners, IROC
suspension, alum shaft. Numerous mods.
92Z28convt5spd (stock)
71Impala convt 402BB
BETTER DRIVING THRU SUPERIOR HORSEPOWER!
Member
Joined: Jul 2001
Posts: 206
Likes: 0
From: western mass
your ground should be fine also. your box may still be messed up too. just a thought
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87 z28 bowtie aluminum 420small block dry sump crower lt. wt. knife edged crank oliver lt wt rods brodix track 1's super ram intake slp 1 3/4 headers accel dfi art carr 700 r4 3.42 gears ssm sub frame/ladder bars.....other parts on the way ,soon to be finished!! couple more weeks!!!
http://people.ne.mediaone.net/gdm
------------------
87 z28 bowtie aluminum 420small block dry sump crower lt. wt. knife edged crank oliver lt wt rods brodix track 1's super ram intake slp 1 3/4 headers accel dfi art carr 700 r4 3.42 gears ssm sub frame/ladder bars.....other parts on the way ,soon to be finished!! couple more weeks!!!
http://people.ne.mediaone.net/gdm
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