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Rev Limiter options?

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Have you considered the MSD-6AL. I have one installed in my midget and when you buy the add-on packs, you can set the RPM limit by 100 RPM increments with ease. They even make a passanger compartment mounted sweeper-knob that allows you to change the rev limit as you drive. I've always been happy with this unit and have used it in many of my cars.

JACK
 
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Have you considered the MSD-6AL. I have one installed in my midget and when you buy the add-on packs, you can set the RPM limit by 100 RPM increments with ease. They even make a passanger compartment mounted sweeper-knob that allows you to change the rev limit as you drive. I've always been happy with this unit and have used it in many of my cars.

JACK

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Hi Jack,

I've got an MSD 6A in my jeep, and do like it. For some reason I thought the 6AL was only adjustable in 1000RPM increments, though I've checked their site and you are indeed correct about the 100RPM increments.

Would a 6AL use the stock pickup in the dizzy? I had a magnetic pickup in the jeep with an external ignition module, so hooking up the 6A was pretty straight forward. I checked their instructions and MSD suggests you use the original coil wire as the trigger. This seems like a bad idea IMO since you're limited by the reliability and accuracy of the stock points. Any other options for hooking up the dizzy to an MSD box?
 
I've always hooked up to the stock points and never had any problems and I definitely bounced it off the limiter a few times /ubbthreads/images/graemlins/wink.gif I'm not certain about pertronix kits and whether or not they are compatible. There is also the Mallory Distributor(s) available. Might look into those as well. Somebody else here could probably answer that one. I've always figured if the stock points are good enough to run the engine at RPM I don't see any reason why they wouldn't be considered good enough for a trigger, but then I've only used my for street. But I can see where you would perhaps want more reliability and accuracy as you suggest.

JACK
 
Do you have points in your car, Rob? Seems odd, but if so, you can buy an optical pick up from Crane for about $35 and use it to trigger your MSD.

I have been considering running MSD as well, and I just read a whole slew of posts on another forum claiming that the Mallory Hyfire boxes are much better (as well as a little bit cheaper).
 
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Do you have points in your car, Rob? Seems odd, but if so, you can buy an optical pick up from Crane for about $35 and use it to trigger your MSD.

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You know what, I honestly don't remember what kind of dizzy it has....guess I need to check when I get home! /ubbthreads/images/graemlins/blush.gif
 
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As an alternate, you might consider a shift light.
I got mine from Summit Racing for $33. It has a fully adjustable rheostat-type knob on the back to set RPMs (mine's set at 5800). I never use the tach anymore.

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Valid point. With the ZS, the car used to tell me quite clearly that I was pushing too hard. I would have a significant power loss over 5000RPM that would wake me up if I was staring at cones, but the HS4 is quite happy in the 5000 to 5500RPM range, so I thought it might be prudent to stop myself hitting 6k....she's an original engine with 45k on the odometer, don't want to push her too hard /ubbthreads/images/graemlins/grin.gif

Even if I get a rev limiter, I think a shift light is a very good idea. I'll have to put it on the list!
 
Shift light? Keep your eyes on the track please. These little cars are to be driven by hearing and feel I thought.

Hay that's my fender at your 2 oclock, careful now.
 
well, found some interesting stuff when setting the timing tonight and looking at the ignition system.

Turns out a PO must have played around with the system because I have a 'Pirahna Ignition' ignition module and the pickup doesn't look like it was something factory. I gather 1500s did come with electronic ignition, but this doesn't look stock based on the installation details.
 
oh, a somewhat related question about ignition advance: Does anyone have a graph of the ignition advance curve for a 1500? With the vac advance hooked up, the advance climbs very quickly from about 2-degrees advanced to 24-degrees advanced and then holds at around 24-degrees. The timing light goes from 2-degrees to 24-degrees between idle and roughly 2000RPM. Is this normal?
 
BTW, here are some photos of the pirahna system:

https://www.triumphspitfire.com/piranha.html

Found a little information. Sounds like they were often installed by the dealer in spitfires after the stock modules wouldn't even make it off the lot /ubbthreads/images/graemlins/rolleyes.gif.

It's a photo-transistor & LED pickup in the dizzy that's used for a trigger. Should work perfect for a 6AL down the line!
 
When I bought my 1500 (about 10 years ago), it had the Piranha sytem too.
Fried it in about 6 months and went to points.
Then Pertronix about 4 years ago.
I am using the 25D distributor (from a 1275) with the vacuum stuff removed (my vacuum advance plate is riveted "fixed" so that only the weights provide advance...simple). This is basically the same as a Mini Cooper "S" setup.
I set timing at 30 degrees BTDC using 5000 RPM.
 
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