HEI Rev Limiter ???
Thread Starter
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
HEI Rev Limiter ???
I was looking at info on the Igniter III and noticed it has an adjustable rev limit feature.
I like the fact it is designed to fit under the dizzy cap, so it negates the need to bolt any other hardware in the engine bay.
I already have a tach drive HEI dizzy fitted to my engine, and it works very well, but I'm wondering if there is a replacement module (such as the Igniter III) which can be fitted to provide the adjustable rev limit functionality.
I guess I could restore my original distributor and add the Igniter module along with a new coil, but it would be a lot easier if I could simply fit a device inside my current HEI dizzy.
Can the Igniter III be fitted easily to an existing HEI dizzy?
or is there another rev limit device available for installation within the HEI dizzy?
Thanks in advance for responses.
I like the fact it is designed to fit under the dizzy cap, so it negates the need to bolt any other hardware in the engine bay.
I already have a tach drive HEI dizzy fitted to my engine, and it works very well, but I'm wondering if there is a replacement module (such as the Igniter III) which can be fitted to provide the adjustable rev limit functionality.
I guess I could restore my original distributor and add the Igniter module along with a new coil, but it would be a lot easier if I could simply fit a device inside my current HEI dizzy.
Can the Igniter III be fitted easily to an existing HEI dizzy?
or is there another rev limit device available for installation within the HEI dizzy?
Thanks in advance for responses.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
you can install an external stand-alone rev limiter
or
both accel & msd did offer hipo 4-pin HEI module w/ on-board rev limiter'.
-add-
nothing personal or specific ... "thanks in advance" not as sincere
or
both accel & msd did offer hipo 4-pin HEI module w/ on-board rev limiter'.
-add-
nothing personal or specific ... "thanks in advance" not as sincere
Last edited by jackson; Jul 21, 2011 at 09:49 AM.
Safety Car
Joined: Oct 2004
Posts: 3,924
Likes: 735
From: Youngstown Ohio
You can replace your module with this MSD unit;
http://www.summitracing.com/parts/MSD-83647/?rtype=10
http://www.summitracing.com/parts/MSD-83647/?rtype=10
Thread Starter
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
Thanks for the replies....
That's exactly what I'm looking for.
Significant difference in price between the MSD and Accel units ( $95 vs $140 ), and Mallory also has a module priced at $121 ???
MSD # 83647
Accel # 35373
Mallory HyFire #699
Does anyone have any personal experience (good or bad) with either of these units?
The MSD unit (cheapest) sets the rev limit via shorting a wire when engine is at half cutoff rpm, whereas the other 2 units use a pcb switch to preselect the desired rpm cutoff.
Selectable rpm via a switch would seem to be a better method, but I'd like some feedback from the forum from anyone who has used any of these modules.
That's exactly what I'm looking for.
Significant difference in price between the MSD and Accel units ( $95 vs $140 ), and Mallory also has a module priced at $121 ???
MSD # 83647
Accel # 35373
Mallory HyFire #699
Does anyone have any personal experience (good or bad) with either of these units?
The MSD unit (cheapest) sets the rev limit via shorting a wire when engine is at half cutoff rpm, whereas the other 2 units use a pcb switch to preselect the desired rpm cutoff.
Selectable rpm via a switch would seem to be a better method, but I'd like some feedback from the forum from anyone who has used any of these modules.
Racer
Joined: Oct 2007
Posts: 318
Likes: 2
From: Stow, OH
I do 
The MSD units are the ones that most of your Late Modle short track guys use when they are not allowed to run an MSD 6-t and Dist. Works great with the HEI and rev limiter hits really soft. Its a very good and powerfull setup. I run them for years. 
The MSD units are the ones that most of your Late Modle short track guys use when they are not allowed to run an MSD 6-t and Dist. Works great with the HEI and rev limiter hits really soft. Its a very good and powerfull setup. I run them for years.
Thread Starter
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
Finally got around to buying one of these and thought I'd provide some feedback.
MSD HEI HEAT module, pn MSD-83647
Installation was very simple and straight forward.
BUT
Programming the rpm limit was a bit of a pain, as it would not set when I was grounding the tach lead as shown in the instructions.
Mucked around for a while, even using a wire connected directly to the battery post to provide an alternate ground wire.
Eventually got it to set, so I went for a drive around the block to check it.
It does work very effectively.
Motor pulls strong right up to cutoff and then holds the rpm with an audacious sound of misfiring.
I need to check the accuracy of my tacho, as the needle stops about 600 rpm less than the set value...
Only issue now is I have developed an intermittent loss of power... feels/sounds like a momentary loss of ignition.
Cruising along at an easy pace, I get a sporadic momentary "Hiccup".
I'm thinking there may be a fault in this new HEI module.
No issues previously with the old module.
Anyone encountered any similar issues?
MSD HEI HEAT module, pn MSD-83647
Installation was very simple and straight forward.
BUT
Programming the rpm limit was a bit of a pain, as it would not set when I was grounding the tach lead as shown in the instructions.
Mucked around for a while, even using a wire connected directly to the battery post to provide an alternate ground wire.
Eventually got it to set, so I went for a drive around the block to check it.
It does work very effectively.
Motor pulls strong right up to cutoff and then holds the rpm with an audacious sound of misfiring.
I need to check the accuracy of my tacho, as the needle stops about 600 rpm less than the set value...
Only issue now is I have developed an intermittent loss of power... feels/sounds like a momentary loss of ignition.
Cruising along at an easy pace, I get a sporadic momentary "Hiccup".
I'm thinking there may be a fault in this new HEI module.
No issues previously with the old module.
Anyone encountered any similar issues?
Last edited by OzzyTom; Jan 26, 2012 at 09:40 AM.
Thread Starter
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
For Sale....
1 MSD HEI rev limit module
I returned the HEI module to the supplier here in Australia.
They wanted to test it on their distributor to assess the problem.
Well sure enough they couldn't replicate my problem, so they sent it back to me.
I re-installed it, hoping that maybe it would be OK after my recent dyno tune found my advance curve was not right.
No joy.
Intermittent misfire has returned with this MSD HEI rev limit module.
I put the standard HEI module back in my dizzy, and the motor runs perfectly.
I'm not prepared to spend any more money on shipping this device interstate or back to the USA. Another lesson learnt.
If it aint broke, don't fix it.
1 MSD HEI rev limit module
I returned the HEI module to the supplier here in Australia.
They wanted to test it on their distributor to assess the problem.
Well sure enough they couldn't replicate my problem, so they sent it back to me.
I re-installed it, hoping that maybe it would be OK after my recent dyno tune found my advance curve was not right.
No joy.
Intermittent misfire has returned with this MSD HEI rev limit module.
I put the standard HEI module back in my dizzy, and the motor runs perfectly.
I'm not prepared to spend any more money on shipping this device interstate or back to the USA. Another lesson learnt.
If it aint broke, don't fix it.
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Thread Starter
Burning Brakes
Joined: Dec 2003
Posts: 1,004
Likes: 7
From: Adelaide South Australia
There's only 4 connections to be made....
Ground wire screwed to distributor body
2 wire plug to the pcb module
3 wire plug to distributor cap
and the switched +12V supply to the distributor cap.
Like I said, motor runs perfectly with a standard HEI module.
As soon as I drop this MSD module in, the intermittent misfire re-appears.
It occurs during steady cruising.... engine at about 1800~2000 rpm.
I pull it out, pop back the standard module... and presto. All good again.
If there's a loose "connection" it is in the module.
More than likely a bad (dry) solder joint causing intermittent issues due to vibration or thermal loading.
Not real happy about the situation, but located in Australia it makes it time consuming (and costly) to continue sending this item back and forth to get it tested.
I wanted a rev limiter for peace of mind... but I'm not willing to accept any reliability issues.
I'm not prepared to waste any more time on this MSD module.
As far as I'm concerned, it was a waste of money.
Ground wire screwed to distributor body
2 wire plug to the pcb module
3 wire plug to distributor cap
and the switched +12V supply to the distributor cap.
Like I said, motor runs perfectly with a standard HEI module.
As soon as I drop this MSD module in, the intermittent misfire re-appears.
It occurs during steady cruising.... engine at about 1800~2000 rpm.
I pull it out, pop back the standard module... and presto. All good again.
If there's a loose "connection" it is in the module.
More than likely a bad (dry) solder joint causing intermittent issues due to vibration or thermal loading.
Not real happy about the situation, but located in Australia it makes it time consuming (and costly) to continue sending this item back and forth to get it tested.
I wanted a rev limiter for peace of mind... but I'm not willing to accept any reliability issues.
I'm not prepared to waste any more time on this MSD module.
As far as I'm concerned, it was a waste of money.
