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Rev limiters

Michael Oritt

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I'm thinking about installing a rev limiter on the Elva and have heard mixed reviews on the Pertronix unit. Any comments on it or the MSD or others will be appreciated.
 
Humm.....My brother & I have used the Pertronics units w/o any problems for several years.

What type of problems do they mention?
 
What type of problems do they mention?
-------------------------------
It was really more an opinion of build quality--but I certainly value your first-hand experience with the Pertronix. Thanks for the feedback.
 
Bugeye58 said:
Michael and Dave: In your Vintage groups, are you allowed to run an Electromotive style distributorless ignition?
Jeff

I believe they run VSCCA style rules, which would be a HUGE no,no. I'm not aware of any "vintage" sanctioning body that allows an Electromotive style set-up. Even the more liberal vintage organizations frown upon those and discourage of their use. It really seems to be SCCA, etc where that is allowed.
 
Bugeye58 said:
Michael and Dave: In your Vintage groups, are you allowed to run an Electromotive style distributorless ignition?
Jeff

Jeff--

SVRA and VRG specifically require a distributor trigger. VSCCA doesn't have an ignition spec but only wants to see "minor" modifications to electrics, etc.
 
I run a Mallory ignition box on the TR8 which has a rev limiter. On the BMW I run a MSD box with the rev limiter. The Mallory is easier to set. The MSD requires installing a different chip every time you want to reset the limit. They are both soft rev limiters, which means they will randomly drop the firing to the cylinders once the limit is hit. I like them both. The BMW used to have a rev limiting distributor rotor. I didn't like that as much, but it was cheap and it worked. The good thing with this type of ignition box, is that they can be set up with all kinds of triggers.
 
I run a limiter on the Auto-Xer but not for road racing.

Never felt the need for one on account of there being plenty of time to change gears.
Also....I can feel when I'm outta cam and that's when I shift.

For Auto-Xing, I hold just below max RPM for the simple fact that you save more time holding than you could possibly make up for by getting a little burst of speed out of the next gear.

Believe it or not.....I find Auto-Xing more stressful than road racing.
There is NO time to look at my tach & my brain is seriously overloaded.

Road racing allows you to have a pretty good idea of where your shift points are.
You do zillions of laps on the same course after all.

BTW....I can't help thinking that having just a shift light would be less injurious to the engine than having it shake apart at 7 grand to indicate you are winding it up too much.

(Perhaps the best way would be a light at 7K and a limiter at 7,200)
 
The best stand alone rev-limiter might be the Armteca unit. Made in England. I think Dave Bean and also JAE carry them. half as thick as a pack of cigarettes. Run up to 1/2 RPM wanted and press the red button.
 
tr8todd said:
The MSD requires installing a different chip every time you want to reset the limit.

Uh - just how often do you need to reset a different limit (and why?)

If this is a valid issue for you, and pulling one chip out of the MSD and plugging another one in is too much work (?) for you, they do have a unit that allows adjustment with a dial.....

BTW - you DO know that you aren't supposed to use these limiters as a shift point indicator? They are intended to be set a couple of hundred RPM above normal red line as a backup in case you miss a shift - which is why I can't see any reason you'd need to reset a different limit unless you suddenly changed cam or valve springs.
 
billspohn said:
which is why I can't see any reason you'd need to reset a different limit unless you suddenly changed cam or valve springs.

Ummm.... you really really want to catch the guy ahead of you and you'll remember to turn it back on the cool-off lap so no one will know?
 
Monkeywrench said:
The valvetrain makes for a good rev limiter /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
/bcforum/images/%%GRAEMLIN_URL%%/eek.gif

billspohn said:
You DO know that you aren't supposed to use these limiters as a shift point indicator?

For road racing the light works fine.

I CAN'T see it while Auto-Xing.
(unless I put it on my visor)
And I can't look at my tach.
What else is there?.......Maybe.....

I'm thinking about using one of these to trigger an alarm.
(Like that irritating deuce1/2 air brake buzzer)
pn8950.jpg

Maybe a window RPM switch so the alarm goes off when I'm REALLY at "critical mass"

For regular driving, I just look at the tach.
 
Monkeywrench said:
The valvetrain makes for a good rev limiter /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
And I have picture to prove it.
 
Bosch made a rev limiter rotor , it was used on VW buses in the 70s and I think 911 Porsches

Not sure if they made it for British cars /bcforum/images/%%GRAEMLIN_URL%%/frown.gif

Beaulieu
 
Nuff said: /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Attached photo is what happened last year at Sebring.

Thanks for all the good replies and advice--I've installed a much larger shift light in a better location so I'll see how that works before moving on to a rev limiter.
 

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