Just wondering, i just chucked my MSD coil and now my car runs perfect, no more break up at 5000+rpm. Only thing i really have is MSD wires and NGK plugs. Just wanna know how much hp/boost stock system can hold.

 

Check the sig for details but I just got rid of my 6BTM box because it kept going sour on me.

I am running about 9-10 psi with no sputtering problems or blowing out the spark yet.
Eventhouh the car feels good and my tune is pretty Good for a street tune, I really need to get it on the dyno. I feel that I am giving up some HP to true dyno tune and testing.

Hope that helps,
Claude

 

OEM wires, Crane HI6-TR, Accel coil, really cold plugs (NGK "11" heat range).

Rich Krause

 

I know your car (Rich) is a insane machine but why so cool. I have NGK "6" is that a bad selection? Its what most people said to use including ATI.

Thanks for the reply Rich and Claude!

PS Rich do think i should invest in a MSD/Crane ignition box with my setup?

 

I am using moderately high boost (~14psi last year) and nitrous and want to take every precaution to avoid detonation. Interestingly, the Crane box and Accel coil has no problem firing the very cold plugs I am using (the center electrode is slightly retracted, so it is a VERY cold plug). Now, I do not run very high rpm (6,200rpm redline), so that may help the ignition out.

Back when I was running ~10psi, I tried running the car without the Crane box. It would miss at WOT above ~4,500rpm. It takes more spark energy to fire plugs with high cylinder pressure (from boost or a high CR). So yes, you need a box to supplement your stock ignition.

Rich Krause

 

You had problems at the high RPM previously, and I quess you found that the coil is bad. That make since. Same thing happen with my friend's car.

I am running the crane Hi6-TRCII, PS92 coil, MSD 8.5 and TR6 plugs.

I would definitely recommend getting an ignition amplifier as well. It will only help and it is a must for me. The only one that did not state that he is using an amplifier is Jim Moran (intmd8) at LS1speed and making insane power 634rwhp. Most everyone else has a box.

Most people really like the MSD better than Crane, but my Crane has been fine. However, Crane has replaced my first box for free when it burnt up inside a couple of years ago. If I did not have one, I will buy an MSD or think about the coil packs.

 

I never had a problem with mine when it was stock...or even with just the HOT cam...but since the 383, even before the blower it would break up on fast acceleration (in 1st and 2nd gears more than 3rd or 4th). I replaced my MSD coil....still did it. Added the 6BTM box just to see....still did it. I am going to try a Jacob's Coil that I saw on a friend's car here in town. He has no problems with the ignition at all on his car. Just hate to pay $120 for a coil.


Other than that, I am using Accel 9000 wires, and AutoLite 104 plugs (I would like to find AC Coppers but I can't find a conversion for the orginal AC 41-906)

 

[QUOTE]Originally posted by 1LEThumper
[B]I never had a problem with mine when it was stock...or even with just the HOT cam...but since the 383, even before the blower it would break up on fast acceleration (in 1st and 2nd gears more than 3rd or 4th). I replaced my MSD coil....still did it. Added the 6BTM box just to see....still did it. I am going to try a Jacob's Coil that I saw on a friend's car here in town. He has no problems with the ignition at all on his car. Just hate to pay $120 for a coil.


I would not buy anything from Jacobs! Nothing but problems with it. Stick with MSD. Sounds like you have something else wrong, maybe plugs and or wires. My motor runs perfect with MSD ignition.

 

Well I have went thru many different plugs about 5 different sets of wires and 4 MSD coils. I'm on the second motor now, I went to a solid roller this time so for those thinking it was valve float, I guess we'll see when its on the dyno.

All I can say is that it (the miss) is related to how fast the motor spins up under a load and the faster it is accelerated the more likely that it will have a miss. Almost like someone turned the key off and then right back on around 5800-6400rpm then it comes right back. I can accelerate all the way to 7k slowly in any gear (1-4th anyway) and it never does it.

In all honesty I don't know what it is but I think its electrical related. I have checked all systems this time with a multimeter just to make sure everything was ok.

I know its not the Opti because it has been replaced and my friend with his '94 seems to have the same problem and both of us have went thru about the same different sets of iginition components, and our motors are no where near similar anymore.

I know the guy in town, and he is running a MSD box with a Jacob's coil, MSD wires and AC plugs. He has had no problems with his car. Not saying its the best but its working better than what I have now.

And personally I still think all the MSD boxes (and ones like it) are just a bunch of crap but it uses a spark rev limiter instead of a fuel cut, and I have the option of in car timing retard as a back up incase something goes wrong. I have never seen anyone ever prove anything good or bad with any of the iginition boxes besides just quoting something off of a web site.

 

FWIW, I can think of a few Jacobs coils, boxes… that have been working for 5-10 years with no issues, I can’t name one MSD that has. The accel box that I’ve been using recently has proven more reliable then the MSD boxes that I’ve had, but it did fail at one point (OTOH, Accel was great at replacing it…)

 

I first had a MSD6BTM but after two went bad I just went with a MSD 6AL , MSD BTM(stand alone BTM) and a Nology setup, and MSD 8.5 wires. for the last four years it has help up. After the 6BTM went south for the second time I talked to a tech guy at JEGs or Summit, and he told me they have a higher rate of failing and suggested the 6AL, which he ran on his S/C setup. And like I said the 6AL, BTM and nology coil have done very well these last several years.

 

Im using an msd digital 6. I personally dont like using reatard boxes but rather would like the timing issues taken care of via the computer.

 

As my sig says, I'm running a complete accel ignition. I've had it on this car for over a year and a half with no problems yet. I've ran MSD on other cars and had good luck with them also.I'm running an autolite 104 plug with the gap set at 42. Accel 9000 wires, accel box, and coil. Runs great with no missing.

 

The reason I'm not recommending Jacobs is it did not work with my blower motor, the MSD digital 6 did. The Jacobs would break up at high rpm. Also, I had a Jacobs Omni Magnum ignition unit fail on me on my truck, and it is just a stock engine. MSD has won more races than all the others combined. All the racers use this ignition. How many use Jacobs, none that I know of.

 

Forgive me if this has already been posted(I just scanned through the responses quickly).

I had ignition break up on my blown/stroked LT1 at 4,900 RPM. I called MSD to see what they thought and what I was told was that the WHITE wire coming from the MSD box MUST be 3 to 4 inches from the ORANGE/BLACK wire or EMI (electromagnetic interference) is likely to take place. In my case, that's what it was. I had the wiring harness that I purchased with the box. In the harness, the WHITE and ORANGE/BLACK wires are run side by side. After removing the harness and hard wiring the setup, with the WHITE wire separated, I was able to run the car up to the 6k rpm shift point with break up coming at about 5,800(need new coil). BIG difference with nothing more than isolating the WHITE wire.

If you have an MSD box, this is something you may want to check.