Sonix

iTrader: (1)

I've got a normal old school vacuum advance distributor.
I'm thinking about adding;

http://store.summitracing.com/partde...part=ACC-35361

and

http://store.summitracing.com/partde...?part=MSD-8226


Are these good upgrades from stock? Anything particularly wrong with them?

Thanks

Apeiron

What's wrong with your ignition system now?

84z28350

No bling...



Seriously though, unless your just looking to burn some money i wouldnt bother unless your current setup is having problems lighting the fires!

5678TA

they are better then stock, but if your not missing in the upper rpms then why change it?

five7kid

iTrader: (14)

Stock HEI starts losing it around 4500 RPMs. You don't have to have a full miss in order to suffer from it.

I'm running the CC version of the module in the Camaro, and was running that coil in the 396 until I went with an MSD Pro Billet distributor recently. No complaints about either product. Some people have reported problems with the Accel module, but I haven't had any since installing it in 2001.

Sonix

iTrader: (1)

Five7 hit the nail on the head there. The car seems to start to gain power over 2400RPM or so, and above 3500RPM you really need to hold on, but it seems to really lose steam at around 4800RPM. Based on the setup, it should still make power until ~6000RPM, unless I did a seriously bad job porting the heads. But i'm thinking about the guys that run bone stock heads like this and massive cams, and spool to 7000RPM, ie, the cam sets the powerband.
My dist. is ripped from a JY cutlass, with the crane adjustable vac can, and a welded slot. With a cap and rotor, but everything else is stock.

I was toying around with the idea of buying a $220 Pertronix piece, but I just keep thinking that if I can get 90% of the functionality with $80 worth of coil and module, why bother dropping the extra 140 bones? There are so many other things to spend my cash on.

So that's the two main things I was wondering:
- Is it true that the stock HEI seems to lose steam at around 5000RPM? From Damons tech article and Five7's thoughts here, it seems to be so. I'm wondering if $80 worth of parts would *most likely* help gain a bit of top end charge?

-and, are these parts that i've listed reliable, or have they been known to make DOA type of parts? There's nothing more of a pita to diagnose than an ignition/electrical gremlin, so I don't want to buy a dicey part.

I think summit also makes one or both of these parts, but since the price was identical, I chose these 2 off the top of my head. Chris, do you agree that a stock HEI might be limiting my performance?

I'm going to be placing a summit order most likely later this week, i'm going to show my machinist my cylinder head and see if he knows why i'm breaking pushrods. If he needs to machine it, great, if I need new parts, i'm calling up summit and spending some grad present money. (insert smiley of guy throwing greenbacks up into the air)

Thanks


oh yea, ps- another thing was - these parts are right for me? ie, 4 pin module is right? That coil drops in? It's a good one to use in my case, or is there another one thats cheaper and works as well, or a few bucks more and is wayyyy better, etc?

Apeiron

A lot of people have said that there were high RPM problems with the stock HEI modules, especially the early ones. Some say the later ones were better, some say they're all junk. I ran stock 4 pin modules from the junkyard in rebuilt distributors up to 6500 on my old engine with no problems, and didn't notice any difference between them and the MSD 6A that I had.

Then again, a lot of people have said that their Accel modules died, which is contrary to five7kid's experience. I'd believe that a few of those failures could be due to improper installation.

To my mind, ignition is a pretty simple thing. Either it makes a spark and lights the mixture reliably and consistently, or it doesn't. Sometimes I think that for the most part aftermarket ignition companies are making most of their living on the reputations they made back in the day when a dual points distributor was the best that the factory had to offer. Stock electronic ignitions have come a long way since then.

Then again, I've got $666 worth of MSD stuff on my car, so it doesn't seem like I want to use the stock stuff either.

In any case, yes you've got a 4 pin module, but you'd want an 8225 coil to fit a large cap HEI. There's also the MSD 8501 "Ultimate HEI" kit that comes with a new cap, coil cover, rotor, rotor bushing, coil and module. If you're running out of steam at around 5000 RPM, then maybe some ignition upgrades might help. At the very least, they're not going to hurt anything.

Sonix

iTrader: (1)

Argh, that 8501 kit runs $170. That's more than a basic entry level distributor.
Then again, the 8225 coil is twice the price of the one I listed.

So my choices are;
-Summit $99 distributor
-8225 coil, ACC-35361 module, $120 total. I'd re-use my current parts store cap and rotor.
-MSD 8501 kit, $170. This comes with cap and rotor.

I'd move my crane vac can over to the summit dist if I got that one. I assumed the summit distributor would have MSD/ACCEL internals rebadged anyway. Would this be a wise move, or am I just "upgrading" to exactly the same as what I have now?

Is there anything special about the MSD cap/rotor that makes it worth that added $50 over buying just the coil and module? I think a cap/rotor from a parts store locally is still way under $50 if I were to replace it anyway- anything making the MSD one special?
Thanks

Apeiron

The Summit distributor is probably just going to have a stock replacement coil and module, made by Standard or Niehoff or someone. Maybe a slightly better module than you've got now if yours is one of the "problematic" ones, but otherwise pretty much the same.

The MSD cap has machined brass terminals instead of the die crimped aluminum ones that are on the cheap caps.

If you're going to be upgrading the coil, it's not a bad idea to use a low-resistance rotor bushing like MSD P/N 8412. The increased voltage of an upgraded coil and the resistance of the stock bushing can cause the bushing to overheat and damage the cap or rotor. I've run external Blaster series coils through the stock bushing with stock caps and had no problems, though.

Sonix

iTrader: (1)

Hmm, I don't think there's huge benefit to going to an external coil, and it looks like it's circa 1965 to me. I think i'll get the
8412 bushing
8225 coil
and I was going to try to find an MSD module, but I couldn't find one on summit, only the $80 one with a built in rev limiter. So the ACCEL one I listed before.

Thanks

Tobias05

that rev limiter would be pretty cool to have, saves buying an ignition box.

5678TA

rev limiters are cool.. especially the 3step with adjustable launch control.. but thats for the all out racer running a manual trans who is tired of trying to hold the pedal still at a certain rpm for 3-5 second every run.. (ie. me) lol

five7kid

iTrader: (14)

Launch rev limiter not limited to manual transmission applications.

Also not legal in all classes.

And, totally unnecessary on the street.

Sonix, how does your timing act at the upper RPMs? I discovered my GMPP (ZZ3) distributor was rattling the weights around at max advance because there was no positive stop for the advance mechanism.

Apeiron

A Pertronix D2000 should be about the same price as the Accel module, and probably has a better reputation. Match it with a D3000 coil for about half the price of the MSD. There's also the D8000 series of HEI upgrade kits that include cap, rotor, coil, module, and advance set.

Apeiron

The typical amout of end play in a stock distributor also allows for several degrees of variability in timing.

five7kid

iTrader: (14)

Should have mentioned mine was shimmed to around .035", but you're right - something to address.

Apeiron

IIRC it works out to something like 1 degree of variability for every .010" of play.

Sonix

iTrader: (1)

Yea, I shimmed it to ~.012" last summer. I'm not sure how else to answer you five7, what do you mean what do the weights do at the upper RPM? I can't see them, so...?

Ok, i'll move my loyalty over to the pertronix 2000 and 3000 parts then. I'll look into ordering this stuff later this week hopefully.
Thanks

five7kid

iTrader: (14)

Just using the timing light. I'm not saying I was watching the weights, but rather what they were doing to cause the timing to jump all over the place.

Sonix

iTrader: (1)

I've got the stuff now. Quick question - where does that low resistance bushing even go? I don't remember seeing something like that last time I tore down my dist...?

Apeiron

In the cap under the coil.

Sonix

iTrader: (1)

I finally did this today. I haven't had a chance to really run it up in the RPMs yet, but it feels like a "feel good" mod so far. I"ll post back if it changes anything drastically in the upper RPM range.

Tobias05

whats the word on the new parts sonix?

Sonix

iTrader: (1)

Not much change i'd say. The higher end power seems to be more of a fueling issue, since now it does noticeably slow down at over 5000RPM, but sometimes it also bucks, the telltale "float empty" type of thing.
After 5500 RPM i'm thinking i'm just running out of cam. I'm going to make sure I can get fuel all the way up there, then find out how it runs. I'm guessing it was fueling holding me back from higher RPM all along though

327???

My 327 w/ xe268 was done at about 5500, but I had unported 305 heads and a non-rpm performer intake. It had a smooth drop off in power though, no surging.

Have you checked fuel pressure yet? Maybe add some fuel to the secondaries. What carb?

Sonix

iTrader: (1)

Yea, I ported the bejesus out of my 416's, and put in 1.94 intake valves.
No, i'm going to tweak the carb on the weekend, I don't have any free time until then. Lots to do on this car, not much summer left...
It's a non -cc qjet. DR rods and F hanger. I think my pump shot is a tad too large, so I might change holes in the linkage for that.

I think the secondaries are alright, i'm worried about volume of fuel from the pump, due to the surging/bucking. Stock style pump on block.