peterc005

Hi,

recently I bought a MSD GM Dual Connector Coil (Part No. 8226) replacement coil for my 1988 L98 TPI stock engine and it seems fine.

I'm also thinking of getting an MSD Digital 6AL Ignition Control (Part No. 6425).

Do you think that, given the HEI is pretty good anyway, that the MSD 6AL Ignition unit would make a worthwhile difference?

peterc005

Would also appreciate any comments on the MSD HEAT HEI Module (Part No. 83647)

LB9GTA

iTrader: (1)

I bought a MSD digital 6+ and I noticed a difference! But I had 10.9-1 compression.
And I had nitrous and needed the rev limiter and the 20 degree retard for easier starting.

peterc005

I've been looking for a before and after 6AL dyno tune graph for a TPI SBC.

From what I've read, the 6AL doesn't make as much of a difference with a HEI.

tpi88camaro

iTrader: (7)

Unless you have a power adder of some kind and need spark retard, or high compression, I think there are better things to spend your money on. There just isn't that much of a difference on a stock engine to warrant the money spent on it. My .02.

TTOP350

iTrader: (8)

A MSD 6AL box or your whatever brand you like, makes a big diff. Much more than the coil will.
I have a cleaner less gasy smelling exhaust along with a better throttle response on all the cars I have put them on. More power? I honestly have never dynoed one to know for sure. Better get on that.

peterc005

@TTOP350 - is your car a TPI?

That's the problem with MSD 6AL unite, some people say they are a waste, others recommend them.

Would be easier to see before and after dyno charts or some other way to measure how effective they are.

TTOP350

iTrader: (8)

Yes, they are all TPIs but my 70 formula and its not finished... yet..

peterc005

What sort of difference would you expect on a new stock L98 TPI?

conlinj

iTrader: (3)

I doubt I picked up any hp, but I did notice the drive-ability and gas mileage benefits. I would say its a worth while investment

1MeanZ

iTrader: (9)

I'll second that. I put an Accel 300+ on my IROC (its still on there by the way) back when it had the LB9 under the hood. No real power gain but got better starts and a 2mpg increase in mileage! I was shocked and maybe thats not normal, but thats what it did. I'll be putting a similar ignition on my GTA because I want the mileage and a rev limiter.

Kevin91Z

iTrader: (1)

I dynoed my engine with an MSD 6A, and it made a 2 horsepower difference at the rear wheels when I removed the MSD 6A and went back to the stock ignition on the dyno. I have 10.5:1 compression and no power adders.

In my opinion its not needed on a stock engine unless you're running a power adder.

StevenB L98/LS1

I had it on my 91, and noticed a nice difference over the stock setup. It has it's benefits, but for some reason why i never did find out why my MPG was worse with the msd on. When i ran it back to stock my gas mileage was better, so idk if it had anything do with the colder plug i ran or if it was timing but i liked it when i ran it on mine. I noticed a better take off and spark, and throttle response was so much better. other than that, i dont feel like it was worth all the money i put into it though

peterc005

The MSD 6AL is hard to figure out. The recommendations/criticisms seem 50/50.

I suspect when used with an old points system it would be more noticeable, buy maybe the HEI is good and hard to improve on?

86White_T/A305

Back when I had my 355tpi and my 383hsr I can say my 6al did improve my idle,gas mileage,throttle response and over all efficiency.Both my motors were built and cammed so having the 6al came in handy.If you are stock then I wouldnt spend the money,get an msd coil,good plugs/wires and dizzy will be plenty good for a long time.Modded engines will see more use of an aftermarket ignition box,I got lucky and got mine for free at the time lol.

peterc005

Is that because the stock ignition system starts to break down over 5,000rpm and a stock motor doesn't rev that far?

TTOP350

iTrader: (8)

Nope. stock ign is fine up into 7k rpm an more. Other than the 6AL my ign is stock and I can unhook the MSD and still rev it to 7500rpm. The stock coil is just fine..

peterc005

It's still not clear whether an MSD 6AL unit would help a stock L98 TPI unit.

Sounds like littke change in HP, but possibly a little better MPG, starting and throttle response?

Twin_Turbo

iTrader: (25)

MSD = one more thing to fail... their service dept. is very good but I assume they probaby had a lot of practice

If it was me, I'd spend that money on some SFCs if you don't have them

peterc005

Already got SFC and a good suspension setup.

Looking for easy ways to get some more from the L98.

Waiting for extractors, will put in a 3" exhaust. Got a spare TPI setup which I will port and gasket match. Also have done the TPI coolant bypass mod and will get a new set of injectors. Have bought a new MSD coil and will bump the spark advance a bit.

Once concern is reliability of the 6AL and there seems to be lots of failures. You'd hope the newer 6AL 2, being digital, has less to fail and would be more reliable.

Looking for quick and easy ways to get a bit more from the engine. The question is whether the MSD 6AL is worthwhile?

Twin_Turbo

iTrader: (25)

haven't had an al2 fail yet, however a 6 digital plus bit the dust after 5 minutes

I'd do injectors before msd, the stock injectors are junk. I got some bosch replacements from southbay, the yeller ones with the tip extension...the car is MUCH faster now. I have a couple and this particular one had probs w/ my LB9 5 speed, It should be a bit quicker than it now, very noticable difference.

ASE doc

I haven't had any trouble with my Digital 6. My friends that run them all have had good luck with them as well. I like the adjustable soft rev without having to buy different chips. Before I installed the new ignition controller I was running an Accel 300+ that did take a dive on me. I had the rev limiter set on it but when I would hit it, the engine would nose dive until it hit 3,500 then rev again. It was a pain when I missed a shift. Now, I can hit 6,900 and the engine will just hang right there until I pull my head out of my *ss and grab the next gear. For heavily modified engines, where fuel mixtures can be all over the board, the high spark current of an MSD box and coil is pretty much a necessity, it seems to me. Be sure you have wires, cap and rotor that will stand up to higher voltage though.

1MeanZ

iTrader: (9)

It's funny how different experiences can be. I've had the Accel 300+ in my IROC since 2003. I've probably put over 50k miles on it. I've also ridden the rev limiter autocrossing it or missing a shift as well and it acts fine.

All this being said, I'll be trying MSD's new digital 6AL on my GTA shortly.

TTOP350

iTrader: (8)

Another thing to remember is these boxes use up spark plugs up to 10 times faster. Because (MSD box) has 10 sparks per fire.
So you have a 100,000k mile plug and they should be checked/changed every 10k miles or so...
Its not a bad thing but just something to keep a eye on..

peterc005

I'm still trying to understand how the MSD benefits an L98 TPI.

I thought the problem was that the coil didn't get enough time to recharge between sparks at high revs?

If the MSD 6AL unit is generating ten times as many sparks how does this work?

conlinj

iTrader: (3)

The multiple sparks only last through the first 20 degrees of crankshaft rotation, after that it is only one spark like factory, albeit much hotter.

1MeanZ

iTrader: (9)

most multiple spark discharge ignitions are not multiple spark above 3000rpm as far as I know.

TTOP350

iTrader: (8)

If your tach jumps around, you may also need a tach adapter. http://www.msdignition.com/product.a...709&terms=8910

MSD stands for...
Multiple Spark Discharge

I copied this right from MSDs web site.
OPERATION AND FEATURES
DIGITAL OPERATION
The Digital 6A and 6AL use a high speed RISC microcontroller to control the ignition's output while
constantly analyzing the various inputs such as supply voltage, trigger signals and rpm. The high
speed controller can make extremely quick compensations to the output voltage, multiple spark
series, timing and rpm limits while maintaining precise timing and accurate rev limiting. The circuits
and controller of the MSD have been thoroughly filtered to create protection against Electro Magnetic
Interference (EMI).
CAPACITIVE DISCHARGE
The Digital 6A and 6AL feature a capacitive discharge ignition design. The majority of stock ignition
systems are inductive ignitions. In an inductive ignition, the coil must store and step up the voltage
to maximum strength in between each firing. At higher rpm, since there is less time to charge the coil
to full capacity, the voltage falls short of reaching maximum energy which results in a loss of power
or top end miss.
The MSD Ignition features a capacitor which is quickly charged with 520 - 535 volts and stores it until
the ignition is triggered. With the CD design, the voltage sent to the coil positive terminal is always
at full power even at high rpm.
MULTIPLE SPARKS
The MSD produces full power multiple sparks for each firing of a plug. The number of multiple sparks
that occur decreases as rpm increases, however the spark series always lasts for 20° of crankshaft
rotation. Above 3,000 rpm there is simply not enough “time” to fire the spark plug more than once,
so there is only one powerful spark

z 28 jari

iTrader: (1)

This is pretty good info: http://www.dainst.com/info/circuits/msd6a_02.pdf

peterc005

Starting to get the picture.

So, the main thing the MSD does is ramp the input voltage up from 12 to ~500 volts for a better spark?

I guess at higher revs when the coil has less time to file up the higher voltage from a CD ignition helps by stepping up the input voltage to help?

Can't see what the point is of multiple sparks. Once the mixture has fired what is the point of further sparks?

ploegi

I rather liked my MSD box.... quicker starts, little more pep in the lower RPM range, better throttle response, smoother idle/running. Didn't really notice any MPG gains...

The idea behind the multiple sparks is to make REAL sure you get good combustion of ALL the fuel in the chamber.

peterc005

Ok, it's starting to make sense now.

I'd guess that as the 6AL produces a better spark at daily driving RPM and better combustion then it would improve emissions too?

Trevmust

so the 6AL2 would do wonders on a 383?

Tibo

iTrader: (15)

I used one on a built 350 with heads, cam and 10:1 CR. I did datalogs with and without the MSD 6A and saw no difference in tps or map readings so I took it off and gave it to a friend. While it may increase mpg or "feel" more "peppy" I haven't seen a dyno or datalog to prove it. A two horsepower gain or a two mpg gain is not enough for me. I drove my Camaro 500 miles last year and 2000 the year before doing cruising and autocross, the cost wasn't justified to me. If yours is a recreational vehicle and you don't do lots of drag racing or you are looking for reasons to purchase one, you probably don't need it.

TTOP350

iTrader: (8)

I can see how it wouldn't be worth the cost if you bought it and gave it away!
I really don't see how it would change TPS or map readings tho. It just gives a more complete burn of the fuel in the cyl.
The only reading I'd think it may change is the 02 sensor but I'd bet it would be a very small fuel addition.
2rwhp is 2rwhp...

Tibo

iTrader: (15)

I was looking at this much the same way you would adjust timing for the best MAP and lowest throttle percentage. Perhaps I was going about it wrong, but I didn't feel or notice anything.

peterc005

@Tibo - your comments make sense.

I'd expect a slightly better combustion and a better burn out the pipe.

Looks like the OEM HEI is pretty good and hard to improve on.

On a good day I might get 2HP, 2 MPG, better start and better throttle response. A marginal improvement, but not amazing.

Johngypsy

Hi guys, been reading up on the msd-6al and thr 300 series pro by accell a lot. I'm alos in the same boat. I actually have the both of them, first have the msd installed and atikk the accell brand new in the box ready to transplant into my l98,
This is what I've found out and Had the both tested all 3 on and off the car with the 300 accell used by the testing place here in Houston. Tx... (Dyno tested)

Done tbr me stock factory coil set up first:

Mods first for the car: (motor performance)
K&N filters (oem covered) x2
Ls1 fans (dual)
L98 motor stock
24 pound injectors
Slp runners
Walboro fuel pump
17 inch wheels and tires used on Dyno testing
Fuel pressure adjustable set at 85 or 90 forgot the amount set at?

And exhaust set up factory to the point of headers just a y pipe and flow master, (cheeses exhaust sys)

So went to test the amount of difference if spark used and more that can be found for our cars, with the stock coil and ignition the car ran a 243.5 hp at the rear wheels not to bad for this set up also I had a 3.42 posse rear end also for got to mension,

Next done the my msd: already was installed just took out the plug and went Into the the msd harness, 5-min job..... Well the car gained 3.1hp at the rear wheels guy there added a hi voltage coil to the Iroc z, he had to cut or tap into the factory coil to have 2 wires: 1 positive+ and the other -black and re-tested the run again, the l98 gained 1.4hp at the rear wheels, not to bad, I also had installed with this set up tbr 8mm spark plugs wores to it all the way threa the testing to it, so with all said and done with new plugs (med grade) for got the name of plugs but was about 2.99 at auto parts store, and in total 4.5hp at rear wheels, when we took off all the spark equipment in exchange for the accel box, started the car and was no where near as smooth running, to an average person who would but the car it would seem normal to them, but as a owner u can notice a HUDGE difference in smoothness and also with acceleration to the car,

So now for the 300 series accel without the hi voltage accel coil, (optional) tbe accel done a 2.9hp difference in perforamce to it, not to bad, remember it's not just about the hp we are looking at better turn key starting up with out these l98 bogging out half the time as a l98 owner to another u know what I mean, the 300 series started up faster then the msd box did, I mean instant turn over, now the guy added his accel hi voltage coil to this set up, ran it again.... The box done the same as starting up and with a smooth wot responce the coil done only .9hp in combined with this set up of all the accel parts added,

The msd did out pwrform the 300 series good, but the start up and smooth acceleration was not there with the msd box, don't get me wrong the msd was also smooth but no where near the spark that the 300 series pro could offer, as far as hp is concerned every little bit helps these car a lot, we did not get a chance to advance the timming as u guys are wondering if that was done.... No,,,,, this was just to see on a regular daily driver based car that we can drive it to Florida and back what can we see with these boxes in better economical perormance and libaliry in over all driving expeareance....

So in concluding, every car is based on what u have under the hood, what u done to it, amount of flow, fuel air, and cam ect.... But over all we decided that the 300 series was the way to go, lower in performance by a few hp! But over all a better starting and driving point to just never go threw the cold starting start up we all face from time to time, we hear stories on how both do work, about how 1 is better then the other, true I agree,,,,,, but depending on what u want your car to do is up to u, drag race her at the track or light to light, the msd will kick some azz, u won't feel 4.5 hp, but it's gaining a door and fender stock to stock when racing the same car it will take it down threw the 1/4 mile, but for me as a daily and also a performer I am installing the 300 series just because I will be driving it as a weekend car or summer car that I don't want to be stuck at at a gas station again, as u guy also know what I mean there.....

They also say Jacobs is the best at 8.7 hp all the at threw the rpm range with power and true spark and it's only about a few hundred in difference, the guy also told me that when u decide to get a msd or a 300 series accel don't go with a used one, people only sell them because they some times shut off and on and will kill your car when it's over loaded with heat! So buyer beware of the used sales unless u know where it's from and at a good deal so u won't get burned out when installing it,....

More testing on these parts and others comig up in the best several months on add ons and bolt on parts for the tune port injection cars,

Would like to also add; every car is different as to performance by miles and so forth, if
Your car is 100% stock may differ in hp range or spark, I've added the add ons to show what was done to get to this point with all said above to gain Perforamce and also stealth start ups.....

Good luck with your camaro its worh the investment ether way u go! Just enjoy it
Ether way......
John
Iroc z parts and supplies
Houston tx.