Hi Guys,

Im in the process of building a 383, i want to upgrade the ignition so im looking for the best/tried and tested solution.

Ive seen numerous setups on the forums with digital control, huge coils etc, but i would like to get your views on what set up/parts would be suitable for the 383.

Im not looking to spend £1,000's or drag it, i just want something that will perform well on the street and give some good performance with future proof upgrades to the engine and HP at a later date.

Your suggestions please gentlemen.......

 

The stock HEI system will do a perfectly acceptable job. An aftermarket system will not give you additional horsepower, contrary to what the marketing BS tries to convince you of.

 

Agree, HEI is fine up to 6,000 rpm or so.

 

Thanks guys, why do people all go for the MSD's?

 

They read too many magazines

 

and they have money to burn as does the Democrats.... also looks good at the local cruises. .. ..

PS, a 1975 HEI is the easiest to hook up. and gap the plugs at .035 if its a high compression engine.

 

I agree on the HEI system. It can be made to run at 7500 rpm with minor upgrades. That said yes I run a MSD distributer and a Crane HI 6 digital box. I run the box so I have a rev limiter which has come in handy many times over. I ran the stock dist. fired by the Crane box for years with very little trouble. My MSD dist costs me less than a HEI would have cost. All my boxes and stuff are hidden. I could care less what people know I run. I don't do car shows any way.

 

Very simple. One guy named Bubba reading a Jegs or Summit catalogue can out-engineer all of GM's billions of dollars and decades of R&D with the simple flick of a credit card.

All that's needed from the supplier's point of view is to market a solution to a problem that doesn't exist.

 

IF you correct the slow advance curve...thats the main advantage the aftermarket distributors have. Of course, a cheap spring and weight kit will correct this on a stcok HEI. No need to go aftermarket for the distributor, unless you have firewall clearance issues (shouldn't on a Vette).

 

I dont know about slow on the advance with 60 foot times of 1.5-1.6. Its full advanceimmediately and right from the bottom. I just took a stock 1975 GM HEI distributor by A-1 Cardone from our inventory out of the box and obtained those times doing nothing else but going along for the ride. Never skipping a beat. And it`s also very comfortable on the street except for the noise.
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http://s238.photobucket.com/albums/f...t=68RedLS7.flv

The noise does one thing for sure, it really attracts a crowd of those show and shiners in a hurry...

 

It would be a good idea to put a pertronix ignition module into your stock HEI and the matching coil they only cost $75.00 for the pair. Then you won't have any misfire trouble up to 7500RPM. Then set your timing to come in between 2500 -3000 rpm for a 36 degree total. Usually this would be 16 intial plus 20 mechanical. Then add 14 to 16 with the vacuum advance can hooked up to direct manifold vacuum buy the adjustable crane or the proform vacuum advance they both work really .

 

Say what?

 

The whole Pertronix kit:
http://store.summitracing.com/partde...1&autoview=sku

The HEI module:
http://store.summitracing.com/partde...5&autoview=sku

Matching coil:
http://store.summitracing.com/partde...5&autoview=sku

 

Well, Guess I must be Bubba. I have the MSD Tach drive distributor, MSD 6ALN box, MSD Plug Wires, MSD timing retard and MSD window switch. Last 2 are for the nitrous. I rebuilt my stock distributor, Recurved to Barry's paper, was constantly changing points and adjusting dwell. I would get it running real good and have to mess with the points after a couple real hard runs. After I changed to the MSD there was a very noticable change in the car. Starts right now, barely cranks. Runs smoother at idle, More responsive, and my butt dyno says it was a good move. Haven't messed with any ignition parts since the change (2 years of driving, over 10,000 miles, lots of hard runs) Guess I got took by that advertising.

 

This is exactly why I used a GM HEI ignition. 200. bucks for what? The GM stuff performed flawless at 1/4 the price. Apparently no one read my reply. That 200. saved from above bought some speed rated racing front runners. The GM junk may not be as pretty as the polished up cruisers stuff but mine works for me. Not many single carb hot rods on the street or track can do it any better.

PS, no operational vacuum advance either...

well, Wally Parks called me a 'Mavrick" too...

 

The vacuum advance is for fuel economy on a street engine and will keep it running cooler and more effient when there is no load on the engine.

The stock HEI is great but you will likely notice more horsepower with the upgrades simply because the stock unit may misfire at anything over 5000RPM.

Lets say his cam gives peak horsepower at 6200RPM but the stock HEI starts to misfire at 5800RPM that would = lost power.

Purchase the parts above and you won't have to worry about any misfires at the REDLINE.

As far as timing goes, your major improvement in power will be from having the mechanical advance curve setup correctly.

It doesn't really matter if it's an MSD probillet HEI or a stock unit with a few upgrades, as long as it doesn't misfire and you have it setup correctly you will get to your peak HP.

The one thing I like about the MSD probillet HEI is you can adjust the amount of total mechanical advance with a simple change of bushings. This could be benificial if you engine doesn't like 16 intitial when hot starting. You could just setup the MSD to allow 25 total mechanical advance and have your initial at 11 to cure starting problems when warmed up.

 

a properly running gm hei set up is good till 7k rpm. this has been tested with a scope. some of that other aftermarket stuff is off the china boat with less reliability.

 

Pertronix is a USA company with a manufacturing plant in Irwindale, California.

I believe MSD ignition is also a USA company with a manufacturing plant in EL Paso, Texas.

 

Not 100% Bubba. You had some stock equipment that malfunctioned (for whatever reason). You made reasonable attempts to repair it, but were not successful. Instead of continuing to throw more money at it, you replaced the unit, albeit with non-OEM parts.

That's a fairly logical and cost effective path. You had a problem that could not easily be solved, and purchased some reputable equipment which cured the apparent problem.

To be 100% Bubba, you must have no real cause to suspect or replace a given part, other than the guy on Speedvision said it was all good (followed by a commercial from the same company) and/or there's a full page colour ad in the latest Jeg's catalogue.

Once you've replaced the part you must now claim that it makes the car run much better, but not be in a position to back it up with any real facts like quarter mile times, fuel economy numbers, etc,etc. Instead, you refer everyone who inquires to the marketing literature that back up your claims.

Finally, you must become indignant when people point out that you may have wasted your money on foolish upgrades.

Bonus points can be awarded for adopting the attitude that anything that GM put on a car was junk because we all know they're idiots and that the bean counters were actually in charge.

So, having said that, thanks for playing the internet version of 'Am I Bubba' but I'm afrad that we can't declare you the winner.

 

Mike,
I don't think anyone here is saying that the GM stuff is junk. I think the GM parts are very good. The ignition systems they have made work extremly well under most conditions. That being said it is when you start going to power adders and long duration cams and things that GM did not intend their equipment to run under. If all the aftermarket equipment is not as good as GM then why is there a multi million dollar business out there selling parts. It can't all be hype. I'll agree that a lot of it is hype and not needed but to put out a broad statement saying that GM parts are better than anything else out there is not exactly right.
The reason I upgraded to a "better" system is GM does not have a rev limiter built into their system. Yes I miss an occasional shift and have used the rev limiter many times. My dist was just flat worn out. To rebuild it properly was going to cost more than a new MSD Billit dist. It is easier to set up the MSD unit than the stock dist. Did I throw away hard earned money?? I don't think so but that is up to me. Have I fallen prey to advertising hype. Probably, but haven't we all at one time or another. My car starts easier and runs smoother than the old setup. As far as top end HP or 1/4 mile times probably not any better but the driveability is improved over the older system.