Testing the HiRev 7500

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Interesting.

I run the old Analog MSD 6/7 and the expensive grade HVC coil.

Even then with the way I do the ground straps only .035 gap.

My .02 = for Free
 
Eye opening for sure.

If you see a news story about an old man who got split in half by an exploding clutch fan, that will be me. Now I'm gonna have to check my 80's msd 6a.

Great video!
 
I have run a high rev 7500 for years with a Blaster coil it has been solid up to 6800 no complaints.but now I see why it likes so much timing. great video.thanks.
 
The first 5 min was enough or me.
What the gentleman ignores is that it could be the electronics in his m/c that is causing the retard.

The only true way to see if the ign is retarding [ or advancing ] is to watch the ign trace on a dual trace osciloscope, where you can see the initial generation of the spark v the spark being delivered on the time axis. Once you have the time difference & rpm, you can calculate any retard.
 
I have been running a 7500 HiRev on my Duster for a few years. Been very reliable and performs great. I run .035 gap on RC12YC. I tried a locked distributor once (not in the Duster) and it would lose about 6 degrees timing at shift point. I don't run locked distributors now.
 
Bewy said:
The first 5 min was enough or me.
What the gentleman ignores is that it could be the electronics in his m/c that is causing the retard.

The only true way to see if the ign is retarding [ or advancing ] is to watch the ign trace on a dual trace osciloscope, where you can see the initial generation of the spark v the spark being delivered on the time axis. Once you have the time difference & rpm, you can calculate any retard.
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I don’t know what to say. You can see in the video the box CLEARLY retards.

By your theory you can’t use my test bench to test for advance.

Now we have no idea if we even can trust a timing curve according to you.

Edit: I didn’t say it in the video because I didn’t think it necessary but evidently it needs to be said.

I know it’s not in the machine. How do I know that?

Because I can run just a points distributor and it will NOT retard.

A Unilite will not retard.

Both show ZERO advance or retard at any RPM.

I guess I need to spend more time making video with just a points distributor to show what zero retards looks like.
 
Newbomb Turk said:
I don’t know what to say. You can see in the video the box CLEARLY retards.

By your theory you can’t use my test bench to test for advance.

Now we have no idea if we even can trust a timing curve according to you.

Edit: I didn’t say it in the video because I didn’t think it necessary but evidently it needs to be said.

I know it’s not in the machine. How do I know that?

Because I can run just a points distributor and it will NOT retard.

A Unilite will not retard.

Both show ZERO advance or retard at any RPM.

I guess I need to spend more time making video with just a points distributor to show what zero retards looks like.
Click to expand...
Bob Mopar is you ??
 
Newbomb Turk said:
I don’t know what to say. You can see in the video the box CLEARLY retards.

By your theory you can’t use my test bench to test for advance.

Now we have no idea if we even can trust a timing curve according to you.

Edit: I didn’t say it in the video because I didn’t think it necessary but evidently it needs to be said.

I know it’s not in the machine. How do I know that?

Because I can run just a points distributor and it will NOT retard.

A Unilite will not retard.

Both show ZERO advance or retard at any RPM.

I guess I need to spend more time making video with just a points distributor to show what zero retards looks like.
Click to expand...
Yes, because we all know what retards look like. lol
 
Newbomb Turk said:
I don’t know what to say. You can see in the video the box CLEARLY retards.

By your theory you can’t use my test bench to test for advance.

Now we have no idea if we even can trust a timing curve according to you.

Edit: I didn’t say it in the video because I didn’t think it necessary but evidently it needs to be said.

I know it’s not in the machine. How do I know that?

Because I can run just a points distributor and it will NOT retard.

A Unilite will not retard.

Both show ZERO advance or retard at any RPM.

I guess I need to spend more time making video with just a points distributor to show what zero retards looks like.
Click to expand...
Wow now you really got me thinking . It always seemed to me that when I ran a duel point Excel with good points and a high performance condenser my top end power was really good (better )you think it could have to do with the timing being pulled from the box on the high RPMs on the rev 7500 box
 
Dart Frog said:
Wow now you really got me thinking . It always seemed to me that when I ran a duel point Excel with good points and a high performance condenser my top end power was really good (better )you think it could have to do with the timing being pulled from the box on the high RPMs on the rev 7500 box
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Very possible. As RRR said above there are times in high gear you want to pull some timing out but you have to test for that.

I can’t say all but most every engine wants less timing at peak torque and more timing at peak power. Which is the opposite of what happens when the box retards and you don’t know it’s doing it.

My mentor told me this story. And it’s true. They learned two important things.

They had one of the very first GM Magna Pulse ignitions. And he and two others were all involved in a Modified Production car.

He was close to running the National record and they all thought the new ignition could put him closer to running on or even setting the record. So they install the ignition, one of the guys grabs his timing light, and they set the timing as it was before with just the points.

They go to the track with the owner and it wouldn’t pull the hat off your head. They couldn’t figure it out.

Back at the shop, a different guy grabs HIS timing light and the timing is off several degrees. Now you have three guys pointing fingers at each other, claiming the other two can’t use a timing light!!

One of them gets the big idea to grab all three timing lights out and hook them up. And all three read differently. By several degrees both advanced and retarded.

That was lesson 1.

Then they got the bright idea to put the distributor and ignition on the test bench just like it runs in the car. And they learned what I’ve been showing in these videos. It had a bunch of retard in it, and the engine didn’t want the timing retarded.

Lesson 1 is all these ignition systems retard with RPM and they are all different even between the same part numbers and date of manufacture.

That’s lesson 2. It’s still true today.

Guys are giving up power by not checking this and accounting for it.

I hate giving up horsepower more than I hate ear aches and watered gin. And I hate both of those.

Everyone should find a guy local to them with a test bench and have them hook the ignition up just like it is in the car and test it.

IMO it’s worth every penny.
 
NT, I've still got a very low-use gold box sitting on my shelf. Still willing to give it a look?

And the timing light example is a good one. Basically, ignore the numbers, and set the timing in YOUR car, with YOUR light, where it runs best.
(At least that's the way i read it).
 
Some of this is why I don't like the rule of thumb - "All in by 2800" curve that's been regurgitated for years. I've gotten clatter by advancing to total too quickly. Even without clatter, mid range pull wasn't as strong. For some cars it may be right, for others it may be way wrong. Kind of what I was talking about in my last video.. lol.. It's work, time, and money to chase tuning. It's not magic.
 
Newbomb Turk said:
I don’t know what to say. You can see in the video the box CLEARLY retards.
Click to expand...
I agree your system retards. Distributor plus control unit. Before you get all bent out of shape because of who the messenger is just hear me out. The distributor you are using uses a variable reluctor sensor that generates on its own ac voltage signal. It has 2 wires.

You can test this with your distributor machine. I don't know if you can trigger a chy. ecu with a distributor that generates a digital signal ( Like a fast distributor, 3 wire that needs power supplied to it) but you can do this test with a fast box and probably a msd 6 box. Use the Chrysler distributor then test the digital distributor and see if there is a difference in how much the "ecu" retards. If you don't have a digital dist. try triggering with a points distributor. I'm not familiar with a unilite but if you can trigger the msd with it you should see the difference with it also.
 
It's long been said on this forum by many including me that point type ignitions can better electronic ignitions with good parts and everything right. It's no surprise to me to see it in action.
 
92b said:
I agree your system retards. Distributor plus control unit. Before you get all bent out of shape because of who the messenger is just hear me out. The distributor you are using uses a variable reluctor sensor that generates on its own ac voltage signal. It has 2 wires.

You can test this with your distributor machine. I don't know if you can trigger a chy. ecu with a distributor that generates a digital signal ( Like a fast distributor, 3 wire that needs power supplied to it) but you can do this test with a fast box and probably a msd 6 box. Use the Chrysler distributor then test the digital distributor and see if there is a difference in how much the "ecu" retards. If you don't have a digital dist. try triggering with a points distributor. I'm not familiar with a unilite but if you can trigger the msd with it you should see the difference with it also.
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I can test the module alone. I just haven’t done it yet. Maybe I have that a try.
 
92b said:
Curious how you trigger it.
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That’s it, I haven’t done it but I know I can. Maybe when I do it or before I do the module as a stand alone I need to do a quick video on my machine verses a Sun because they are vastly different.

I’ll do a short video on what this machine does and then test the module alone.

I know my mentor has wanted this machine since the first time he put his eyes and hands on it.

It will easily test a magneto too.

I have one of those laying around so maybe I test a magneto too .
 
Newbomb Turk said:
That’s it, I haven’t done it but I know I can. Maybe when I do it or before I do the module as a stand alone I need to do a quick video on my machine verses a Sun because they are vastly different.

I’ll do a short video on what this machine does and then test the module alone.

I know my mentor has wanted this machine since the first time he put his eyes and hands on it.

It will easily test a magneto too.

I have one of those laying around so maybe I test a magneto too .
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Do you prefer the Allen over the Sun? I missed an Allen machine that was just about 15 minutes from here. Someone got a great deal. I am always on the lookout for stuff, even when I'm broke.
 
Mopar Sam said:
Do you prefer the Allen over the Sun? I missed an Allen machine that was just about 15 minutes from here. Someone got a great deal. I am always on the lookout for stuff, even when I'm broke.
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The last Sun I used was in high school. My dad bought his Sun machine in 1965. Then he sold it in 1978 because he bought the lie the distributor was going away by 1985.

I know this machine will do things the Sun won’t. I just went out and grabbed the instructions and it says I can test the module as a stand alone component.

I need to try it.

Plus this machine will go to 11,000 rpm and other than the King distributor machine I don’t think any go over 8k.

I know the earlier Allen machines would do 8k but if it doesn’t say Syncrograph on it it won’t do what this machine will.

I bought this one off yellowbullet from a guy in Michigan. I paid 300 for the machine and 300 to ship it.

I’d spend double that if I had to to get one.
 
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