Who makes what? & what do I want to stay far away from.

Thanks

Neal

 

I use an MSD 6AL, and it works great. You should know ahead of time that finding a place to mount any ignition box is tough. Most people, including me, make a bracket and mount it in one of the forward areas where the horns reside. I also use an MSD coil.

 

Fullboogie, do you have a part number for that coil?

 

Yep. They're hard to find, though. Everybody claims to carry them, but it's ALWAYS on backorder. Call Jegs or Summit and order part # MSD 8231. It's the correct coil for the single connector coils on 96 on up.

 

The reason it's so hard to find is because it's new out this year.

 

I have a Jacobs unit. I got the full package so I had to mount a ignition box, coil, and coil trigger, not easy but doable. I love Jacob's products and have use them on my last three cars.

Sam


[Modified by LT4Sam, 12:21 PM 9/26/2002]

 

Use the factory coil, the '96 is one fine setup just the way it is - from the factory it is a low impedence coil. As far as I'm concerned, the factory piece is made to a higher standard than the aftermarket. Now if you had a '95 or earlier LT1 then you would have to go aftermarket to get a low impedence ignition coil.

Don't flame me on this, but unless you need boost retard on an engine boosted by nitrous or a supercharger, you are wasting your money on any add on ignition box to your '96. Further, my experience says all you will get from an add on ignition box, MSD, Jacobs, whatever, is a shorter optispark life and less reliability.

My '95 runs a stock opti and an MSD low impedence coil, it never made more power with an add on box - but those ignition boxes sure left me stranded a couple of times. If you bother to really check out your ignition, you will also find that any of the multi-strike ignitions do odd things with the optispark - like multi striking on only 7 out of 8 cylinders.

Thomas

 

I'm with Green Rocket.

Your stock system will deliver the necessary 30,000 volts or so to the plug. You have a very good stock timing/spark system, assuming you keep it out of the car wash.

Before you spend money, ask for dyno results on a system close to your application. Then decide.

dlmeyers 90 coupe zf6 3 speed shocks

 

OK, Green Rocket, I'm going to have to disagree with you on the MSD ignition box. First and foremost, it gives a RELIABLE rev limiter, which the factory limiter is NOT. The MSD uses spark to limit revs, whereas the factory unit uses injector shutoff to limit revs. I don't know about you, but I'd rather not have my injectors shut off at 6400 rpm when I miss a shift. Besides, the factory tach is a joke. It's inaccurate and bounces all over the place, so the possibility of accidental overrevving is even greater.

Second, the multiple sparks from an MSD gives better throttle response, and absolutely lowers emissions. I know this for a fact, because I've done an emissions test here in Houston with, and without, the MSD box functioning. Back to back tests on the same day, and the test without the MSD produced higher HC's and NOx readings.

I will agree with you on the reduced life of the distributor cap. It will eat up the terminals quicker. For me, it's not that big a deal considering the peace of mind I have with the good rev limiter.

 

I'm not looking at it to increase horsepower. I'm looking at it to maintain horsepower. Dual Rev Limiters, Nitrous Timing Retard, Easy Tach Output, etc.

I'll agree that it causes more wear on all parts of the system, but I can replace an opti in 2 hours and I can replace plugs / wires in 30 minutes. I'll take the added routine maintanence for the extra benefits you get. I too don't like the stock rev limiter, the MSD is such a better system.

The only thing I wouldn't consider in an aftermarket system is something like just and MSD 6A. It doesn't have any special features at all other than the improved spark power which as you said the stock system should be plenty.

 

The main reason why I don't like the aftermarket ignition boxes is they are not reliable. I looked in some of the older MSD boxes, they use commercial temp range IC (0-70*C rated) ICs. They should be using automotive (-40-150*C) or industrial (-20-125*C) rated ICs if they want the thing to last. That combined with the poor mechanical design (wires looped all over the place) and their opti killing tendancies them a poor choice (IMHO). If you're running N2O/Super/Turbocharged, then they are a necessary evil. But for a mostly stock LT1/4, what's the point?

IMHO, for $300 you should get an improvement in performance, not a less reliable car with higher cost repairs.

The PCM doesn't use the dash tach to limit revs. The engine RPM comes straight from the optispark. I'd bet the MSD box uses the exact same signal for it's rev limiter.

Eric

 

Well, MSD 6AL, the one we've been referring to, doesn't cost $300. It costs $180 from any mail order house. As far as reliability, I've run them for years on end, in street cars, and have never had one fail. I don't know why you keep referring to the $300 MSD BTM. You don't need to buy THAT one to get a rev limiter.

As far as poor mechanical design ("wires looped all over the place"), how about just doing a clean install? It's not necessary to loop wires all over the place. My MSD, and all the wires, are completely hidden from view.

I never said the PCM uses the factory tach to limit revs. If you read it again, I'm referring to the driver's ability to gauge when to shift. An inaccurate tach can cause you to overrev the engine, at which point a good rev limiter comes in handy. Hey, it's personal choice. To me, $180 is cheap insurance when I'm at the drag strip. It sounds like you've never run your car at the track, so I can understand you not wanting to spend money for an unnecessary item.

 

I'm speaking of the internal wiring inside the MSD box. All those wires are going to fail eventually esp underhood with the temp and vibrations. I assume that and the improper temp range components account for the high failure rate. Maybe you're been lucky, maybe you're due....

Sorry for the misunderstanding, OTOH I've never heard of anyone blowing their motor using the factory rev limiter, the missed shift is usually the 2/3 missed and dropped into first gear, no rev limiter is going to save your valve train from that.

I do run my car hard, just haven't had time to make it to the strip this year due to the family. In fact, I have a set of MT streets all mounted ready to go. With cool weather and my mods, I expect I'll be ripping off a 12 second run, hope that meets your criteria for the right to make an informed comment.

IMHO, unless you're running N2O/turbo/supercharger, on an LT1/4 all the aftermarket ignition boxes are a waste of money.

Eric

 

Whatever, man. You win. MSD's are junk.

 

With well over 10,000 CorvetteForum members there are bound to be people who have had good and bad experiences with just about anything - heck, there are even some people who would never buy another Corvette because of all the trouble they had.

It is however a fact that the aftermarket electronic add on ignition boxes use lower grade electronic componentry than the factory, ask anyone inside the industry and they will tell you the actual defective return ratio is astoundingly high - no quality circles here! However, a lot of the $$$$ race equipment is quite good - but that's not what were talking about here.

They do however have their place, I absolutely agree that an ignition based rev-limiter is superior to a fuel based rev-limiter. I just wish they were made to a higher standard, and the opti does get punished by the multi strike boxes.

What I can say is that I have seen more than a few add on ignition boxes where there were no indications that anything was wrong, but that was only because the owner never scoped his ignition. Opti's and multi-strike do not go together - I challenge all who have one to scope their ignition, I'm positive that a huge percentage will report back that not all cylinders get the multi-strike.

One of my favorite local dyno facilities has a regular practice of doing one of a customer's dyno pulls WITHOUT the multi-strike box hooked up. Take a guess how often they tell people to run their car without the multi-strike!

I am sure that there are people with positive experiences with the add on ignition boxes on optispark engines - but with absolutely everyone I know they have mostly killed their opti's much earlier than need be.

Do what you must with a heavily modded engine, sometimes a sacrifice in the reliability of one component can have good trade off benefits.

If you have a stocker, near stocker, mild performance LT1/4 engine, then in my opinion it is a waste of money with no clear benefit.

Thomas

 

I've also heard the reports of MSD boxes shortening the life of the opti. In all of these cases the MSD was one of the older style boxes. I think the verdict is still out on the new digital 6 box. As of yet I've heard of no problems with them on the LT1 and am considering one myself for nitrous purposes. For the 1996 LT1/4 the factory coil is fine and doesn't need upgrading. Pre 1996 it is a good idea to upgrade the coil. FWIW :chevy