LG4 ignition system strength?
09-08-2009, 10:51 AM
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Car: 1987 Firebird, Dad bought it new
Engine: 5.7L Vortec w/ LT4 Hot cam
Transmission: 700r4 transgo shiftkit 2600 stall
Axle/Gears: 3.42 '02 SS 6 spd rear
LG4 ignition system strength?
How strong is the stock ignition system on my 1987 LG4?
Is there a HP limit, or just RPM limit that the stock ignition will fail at?
Anyone have ALOT of power with the stock ignition?
Basically how far can i go without addressing the ignition.
Will an MSD box w/ matching coil and module fix the problem?
sorry if any of this is repeat i searched and could not find answers
Is there a HP limit, or just RPM limit that the stock ignition will fail at?
Anyone have ALOT of power with the stock ignition?
Basically how far can i go without addressing the ignition.
Will an MSD box w/ matching coil and module fix the problem?
sorry if any of this is repeat i searched and could not find answers
09-08-2009, 11:26 AM
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Car: 89 Camaro RS
Engine: LO3 TBI
Transmission: 700R4 => WC T-5
Axle/Gears: 3.42 Open Diff
Re: LG4 ignition system strength?
It's a standard HEI system, just computer controlled. I believe it's 40K-50K volts, which is really plenty for just about anything you want to do. I've heard 7500 rpms is the stock limit.
09-09-2009, 10:52 PM
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Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: LG4 ignition system strength?
Its NOWHERE NEAR 7,500. The 87s have the small cap HEI EST distributer. At 4,500 rpm you are already starting to miss, well before 6K its breaking up badly. You need to change the coil and module to get more RPM. DUI Dynafire module and Coil work VERY well. I would use a MSD 6AL as well. With those 3 components I have pushed my 350 past 6,500 MANY times.
09-10-2009, 08:09 AM
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Car: 89 Camaro RS
Engine: LO3 TBI
Transmission: 700R4 => WC T-5
Axle/Gears: 3.42 Open Diff
Re: LG4 ignition system strength?
Its NOWHERE NEAR 7,500. The 87s have the small cap HEI EST distributer. At 4,500 rpm you are already starting to miss, well before 6K its breaking up badly. You need to change the coil and module to get more RPM. DUI Dynafire module and Coil work VERY well. I would use a MSD 6AL as well. With those 3 components I have pushed my 350 past 6,500 MANY times.
09-10-2009, 02:50 PM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
"LG4 ignition" and "strength" should not be used in the same sentence.
I've had mine, with Accel module and Super Coil, above 6000 RPMs often.
I've had mine, with Accel module and Super Coil, above 6000 RPMs often.
09-10-2009, 02:52 PM
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Car: 89 Camaro RS
Engine: LO3 TBI
Transmission: 700R4 => WC T-5
Axle/Gears: 3.42 Open Diff
Re: LG4 ignition system strength?
What exactly is the "module" you speak off?
09-11-2009, 12:10 AM
#7
Re: LG4 ignition system strength?
i upgraded my small cap external coil HEI, with a MSD blaster coil and used an Accel control module and ive had it up to 6000 with no issues. i also used an MSD cap and rotor and 8mm mallory wires with NKG plugs.
this is the control module for my 87 350tpi
http://www.summitracing.com/parts/ACC-35362/
there are also the older 4pin types... look at yours and ull be able to tell the diff. really just upgrade the coil and module, then do new cap/rotor, new plugs and wires and ull be fine for about anything.
this is the control module for my 87 350tpi
http://www.summitracing.com/parts/ACC-35362/
there are also the older 4pin types... look at yours and ull be able to tell the diff. really just upgrade the coil and module, then do new cap/rotor, new plugs and wires and ull be fine for about anything.
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