I have had conflicting opinions regarding the use of an MSD6AL. I have a small block 406 with over 400hp, TH400, and a MSD distributor. The car is going to be my driver seeing high revs occasionaly. I have been told that it is not necessary to use the rev limiting unit (6AL)with the automatic, and to use the regular MSD unit.
And I have been told that I could get away with a high output coil, and no ignition box.
Can anyone shed some light on this?
Thank You
Lee

I have the 6AL w/Unilite and Mallory Monster coil, in my SS454. I spent over $11,000 on the drivetrain build-up, and wanted to be sure I'd light the fire. After several additional build-ups, and other's evals, I now feel I wasted the $400 on this ignition.

My standing recomendation is to use the HEI with a quality module, in all but a seriously blown/nitros engine. (Or a car your 16y/old is going to light the tires up on, after pulling through a car wash......... stratospheric rpms make for expensive repairs!)

MSD, 6AL. Why not have a rev limiter as insurance not to over rev. I know you never smoke the tires or when you do you stare at the tack, not the road. Or even on those occasional high RPM spins you watch the tach. New cars have revlimiters, and the MSD will keep the candles lit.

[This message has been edited by 1bad67 (edited 02-16-99).]

Get ahold of a Crane Ignition catalog....and look at a cut away of any MSD box....talk about old technology! Its still got tubes and stuff in it! Run too hot. Wont take the juice a good CD type box will carry.

NOT MSD! Welcome to the age of new technology!

Check the patent date on a MSD box. Hasnt changed. You'd be surprised.

If not MSD then who?

I'm only guessing, but I'd say the MSD box doesn't have vacuum tubes in it. That being said, it's a fine solid unit, works great, and having a rev limiter is always good advice. I'd highly recommend it.

If an MSD has tubes in it thats's Ok with me back when radios had tubes even I could fix one.I have a friend that runs CASCAR he has an MSD that has been in 7 cars SAME ONE.It is not hard to over rev an auto,what if an axle broke, drive shaft ECT.Get the picture???FRED

Brian we don't bash manufactures either.You did expect Crane to build up MSD did you,what else would they do the sell their own units...FRED

I'm running a similiar drive train, and using a used MSD 6A box with a new MSD distributor. It has been a very reliable system. I can't say as the 6A box has improved my performance (as in lower my 1/4 mile times.) In my opinion the MSD distributor with its tight tolerances and the ability to tailor the advance curve will be all you need for performance. As I recall the multiple sparks occur only at lower RPM's. Also, make sure your tach is compatable with an MSD box or you will have to buy and expensive adaptor/converter.

The rev limiter is insurance that you won't accidently damage your valve train. You must be the judge on the risk in this area. BTW, I have found all MSD parts to be very high quality.

Hey Fred,
I didnt "bash" anyone. I simply stated the things that I have seen. When Crane took over the Allison company, they took on their ignition program. When I was at SEMA in '96, I saw the cut aways myself. They dont lie. Now they are in their catalog. I've run msd stuff for years. I didnt say it was bad, I said it was out dated. Isnt that what this place is for? To voice knowledge gained? Opinions? Yeah, I'm hot on them right now because I've seen it in person, I run it myself, and it works. Plain and simple. I'll tell ya what. I'll yank my Crane catalog out of my catalog rack, scan the photo, and put it up as a link. Then that way, you dont have to rely on my words, but facts. Maybe Crane's web page has more infor for ya? I'll look there too. Has anyone else run a CD type igniton? Crane or Jacobs? Has anyone else done the reasearch on these types of boxes? I'm intrested to know what others may have seen or expirenced.

http://www.cranecams.com/CraneCams.htm
http://www.jacobselectronics.com/
MSD's site seems to be down.

I've never known anyone to go faster with an amplifier or CD box. these companies get by on marketing and our desire to have an "advantage". a good HEI curved with a machine is the best way go. however GM makes their own "msd", its blue says GM thats all. I've seen it on their NASCARs and it's the same price as a msd6a...hmm...

2 failures crane boxes, back to MSD. 1 Msd failure 8 years and it was used. Tryied the crane when they first came out. Could have been a manufacturing problem, but I wasnt the only one, MSD has now stepped up with the digital 6a. Talk about technology.Is that crane digital? Dont remember.

As promised....
http://soiroom.hyperchat.com/tw/cutaway1.jpg

This may take a few seconds to load, its a big file.
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