TedH

I'm considering an Accel Performance HEI Module to sustain ignition Spark above 3500rpm. Right now, I have an Accel Performance distributor but I am not certain the module is a Performance module.

Anybody with real documented dyno results showing improved spark/performance over 3500rpm with intro of performance HEI module?

Also, let me know the type of module you run in the poll below. I tried to allow for about all types of modules but if yours isn't here add it.

TedH

ttt. Come on folks, there have to be alot of HEIs on this forum. No aftermarket modules?

Captain Morgan

I had purchased a flame thrower module, and dynoed the vette before and after. No difference. I had the stock, 23 year old module, in the vette before, and adding the flame thrower didn't produce any measurable results on the dyno. However, if you haven't recurved your timing, to get total advance of about 34 - 36 in by 3000 RPM, you are losing a few HP's there. I suggest Lars' recurve kit. Very easy to install, and biggest bang for the buck.

PureSilver

haven't decided on what to do with mine yet- do any hot HEI setups affect the electric tach?

bence13_33

Ted:
I'm running the stock AC Delco HEI ignition module in my distributor, the same one that came with it back in 1976. I've never changed it. My biggest performance gain was timing related. My distributor was set at 29 degrees total timing. I hooked a timing light up to it and set it to 38-39 degrees total by 3000RPMs. My MPH jumped from 115.91 to 117.72 MPH in the 1/4 mile. It gained 1.81MPH I don't know what that translates to in horsepower gains but it was significant.

Pete79L82

Ted:

I have done back to back dyno runs on motors with different HEI modules in them. I have tried every manufacture I could think of. On medium and low compression motors (under 13-1 compression) and under 7500 RPM I could not find any HP difference in any of them. They didn't gain any horsepower and they didn't lose any horsepower.


If you want to save yourself a little money keep what you have. If you want to brag about having the latest "hot product" buy whatever brand you like ( and get a free decal along with it :lolg: )


It is amazing when you don't get parts from people that advertise in your magazine how much different the dyno results are!

Captain Morgan

Ted, concerning the timing, bence is running a big block so his total timing can be a bit higher. On the small blocks, you generally don't want any higher than 36 degrees total timing (with vac advance hose off and plugged). If you start to notice detonation, lower your timing until detonation is gone.

BTW, I "voted" for the Flame Thrower because you said to "vote for what you have". I don't suggest that you use a flame thrower because of my previous comment about dyno testing and ill results. The only reason I kept it was because I gave the springs and weights to someone since I already set up my timing. I couldn't return it to JEG'S without all of the components and I'm too nice to take something back that I've already given to someone.

I'd say the claim that the flame thrower package "increased up to 20HP" is because of the weights and springs used in recurving the distributor. I gained 18 RWHP just by recurving my dist.



[Modified by Captain Morgan, 6:29 PM 4/28/2003]

TedH

I'm running about 35 degrees total; all in by about 2500rpm:

RPM Adv
700 25
1500 30
2500 35
3000 35

The engine is very happy with this setup.

Scott78

I'm running stock HEI module but with Lars' recurve kit so I run 12 degrees initial with 35 total, all in by 3000 RPM. I believe the only difference between a stock and aftermarket module is the "dwell" or coil build up time the module develops. Honestly I think the advance curve will get you more performance then the module will.

Scott

turtlevette

I run the MSD module. It seems to give a hotter spark. The car cold starts and cold idles better with it. MSD claims a much hotter spark to 6 grand and will work all the way to 9 grand without misfire.

It must be hotter because i burned up an Accel coil and a stock coil before i got wise and installed the MSD matching coil. MSD also makes a solid metal coil to rotor pin that replaces the stock graphite one. I have yet to put this in, but this thread reminded me. I will install it this week.

The MSD module seems to have more parts and electronics on it. It is about twice the size of the stock module but fits with no hassle.

I believe this to be the best module but i have no hard data to prove it.

Mike Carter

Mallory Unilite, Mallory Coil.

427Hotrod

I used to use a stock GM one in my 427 when it was in the Camaro. That sucker turned 7600 rpm spraying two loads of nitrous on it and it never missed a beat!

I've seen dyno tests that tried to prove one better than the other, but run to run variations were easily well within dyno variables. I'm sure there is something there,but i doubt you'll ever feel it or see it on a timeslip unless you have some other problem that happens to get fixed in the process.

A good stock one will work fine.


JIM

Guru_4_hire

I am looking into an HEI with a hook-up for a mechanical tach hook up

mrvette

Guru, you are much better off with a tach from 75-77 in your car, the old mechanical stuff is just too unreliable....no sense messing with it...just not worth the maintanance problems, in fact it's so bad, I have never seen a tach work on an old vette that's not totally reworked...
the tach filter also needs installed, that filter you have to make....no problem...

GENE

Perfect81

Mallory Coil; Accel Super Ignition Module; AC Delco Rapidfire Plugs; MSD Cap, Rotor, and 8.5 mm Wires

MrJlr

Summit HEI.....basic.

I don't have numbers, but starting, idle, and seat-of-the-pants ALL improved...noticable.

Mike Ward

Why are you guys digging up posts that have been dormant for SEVEN years?

billcarson

interesting to see the old avitar's.some of them may be dead or in jail by now.

jb78L-82

I run a crane HEI ignition module instead of the AC Delco and a hypertech coil in the HEI distributor. As others have said, I can't notice any noticeable improvement in HP but cold start and idle seemed to improve after the install. 36 total timing all in at 3,000 RPM made the biggest seat of the pants difference.

chevymans 77

Accel HEI with Accel super coil on top, MSD moduel with adjustable rev limit.

Car starts when I need it to even after washing engine

Neal