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Michael Oritt
01-21-2007, 06:25 AM
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.

WhatsThatNoise
01-21-2007, 07:47 PM
Humm.....My brother & I have used the Pertronics units w/o any problems for several years.

What type of problems do they mention?

Michael Oritt
01-21-2007, 09:02 PM
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
01-21-2007, 09:24 PM
Michael and Dave: In your Vintage groups, are you allowed to run an Electromotive style distributorless ignition?
Jeff

Monkeywrench
01-21-2007, 09:50 PM
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
01-21-2007, 10:28 PM
Thanks, Bob. I was pretty sure that was the case.
Jeff

Michael Oritt
01-22-2007, 07:56 AM
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.

tr8todd
01-22-2007, 09:10 AM
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.

WhatsThatNoise
01-22-2007, 04:47 PM
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)

JerryB
01-22-2007, 05:11 PM
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.

billspohn
01-23-2007, 03:58 PM
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.

Twosheds
01-23-2007, 05:52 PM
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
01-23-2007, 06:10 PM
The valvetrain makes for a good rev limiter /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

WhatsThatNoise
01-23-2007, 06:23 PM
The valvetrain makes for a good rev limiter /bcforum/images/%%GRAEMLIN_URL%%/smile.gif /bcforum/images/%%GRAEMLIN_URL%%/eek.gif


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)
https://www.msdignition.com/rpm_images/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.

ChrisS
01-23-2007, 06:25 PM
The valvetrain makes for a good rev limiter /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
And I have picture to prove it.

Bugeye58
01-23-2007, 06:33 PM
And I have picture to prove it.

Chris, I think most of us have the same set of pictures!
As well as oil pans mysteriously punctured from the inside.
Jeff

beaulieu
01-24-2007, 11:26 PM
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

DrEntropy
01-25-2007, 08:55 AM
Nuff said: /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

Bugeye58
01-25-2007, 05:41 PM
Gee, I've got some bits just like that!
Jeff

Michael Oritt
01-25-2007, 06:11 PM
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.

beaulieu
01-25-2007, 06:17 PM
The RPM bosch rotor "throws " out a piece that at a certain RPM grounds the system ,

MSD has a set-up , I think called soft touch which kills the spark at one plug at a time

With the MSD stuff you can set a shift light RPM , and with another box set a soft touch rpm

But it will still not help if you are down shifting and over rev /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Beaulieu

WhatsThatNoise
01-25-2007, 06:35 PM
The picture of that bent Carrillo haunts me.

Michael Oritt
01-25-2007, 07:19 PM
Dave--

I don't know if your guy is building up a 1622 but if so and you are interested in reconditioned parts let me know.

The rods were inspected by Carillo--three are undamaged and can be fully reconditioned for about $70 each and a matching fourth is available from them. I also sent the pistons back to Venolia for inspection--undamaged according to them.

WhatsThatNoise
01-26-2007, 03:09 AM
Dave--

I don't know if your guy is building up a 1622 but if so and you are interested in reconditioned parts let me know.

The rods were inspected by Venolia and and three are undamaged and can be fully reconditioned for about $70 each and a fourth is available from them. I also have the Carillo pistons--undamaged according to the Carillo folks.


I'll call Steve Ellis, have a chat with him & let you know.

Sounds interesting!

bugimike
01-26-2007, 05:51 PM
nNothing to do with rev-limiters, but...I don't know if anyone would be interested or even if it is a desirable item, but I still have the set-up for a Capacitive Discharge system. It has to be an antique! I've had it for 20 years!! Brand new in the box.

Hap Waldrop
01-27-2007, 09:23 AM
I sold two really nice Electromotives to go vintage racing, so a big fat no to electromotives, you might get by with one at HSR, but you're asking for trouble.

I tried the MSD soft touch, I hated it.

Bugeye58
01-27-2007, 10:13 AM
Hap, I love my Electomotive! But, I also have one of the good pickups.
If I set one of these cars up for vintage, it'll be with an MSD 7AL2.
Jeff

Hap Waldrop
01-28-2007, 08:07 AM
Oh, I have nothing to say bad about Electromotives, I love them, simple and good, I never had pick up problems, I used the Huffaker 3/8 pick up, but I think the 1/2 Electromotive pick up is just as good though and cost less. If I could run it in vintage I would have never sold it. I have a new points Aldon dizzy I horsetraded for, I'm going to send it off to my distributor buddy Jeff at Advanced Distributors and let him see if he can improve the Aldon, I going pretty simple with my vintage car, it definitely going to be a KISS formula, but I think it will suprise alot of folks, showing them you don't need fancy ignitions, Webers and 1380s to win in vintage.

Bugeye58
01-28-2007, 08:40 AM
Hap, the KISS idea is my plan, too. I've got a .040 over 1275 sitting here, with a nice head, courtesy of Joe, and a new Aldon for it. I don't know what I'll run for a cam, and I've got a set of prepped HS4s on a reworked B manifold. Nothing fancy, just good old reliable horsepower. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Jeff

Hap Waldrop
01-29-2007, 07:00 AM
I've got a .040 over 1275 sitting here, with a nice head, courtesy of Joe, and a new Aldon for it. I don't know what I'll run for a cam

Might I suggest a Comptune HL12, that's a great 1275 cam, been around for ever, won more FP championships than you can shake a stick out.

.366" lobe lift. (we run them with 1.5 rollers)
298 advartised duration
261 durtion at .050"
102 center line ( we advnced that about 3 degrees )

You probably know Peter Morton, that what we used in his motors, that's what Harold Flescher, Craig Chima and many others have used over the years. I an get you one, I also have the oversized valve springs recommended to run with these, your Huffaker head may already have these on them, the retainers are normally gold in color, and the spring is visably larger in diameter that stock.

Bugeye58
01-29-2007, 05:19 PM
I'll keep that in mind when the time comes Hap, but Dave Sr. and I had our differences, and Comptune never left me with a "warm fuzzy".
Yeah, I know Peter and Craig both, and have spoken to Harold a couple of times. (Peter and Jen just had another baby on the 18th. Named her Hayley, to go with their son Austin!)
I can't remember what springs are on that head, and it's too cold to run out and look.
Are more vintage groups allowing roller rockers now? I know at one time they were frowned on. I've got some of Peter Dodds' 1.5:1 forgings lying around if I have to run conventionals.
Jeff

billspohn
02-03-2007, 06:08 PM
A foolproof but hard to find rev limiter is the Lucas rotor fitted to Lotus engines - set for 6500 RPM but adjustable if you have a distributor machine.

I often used one on my Twincam when I was breaking it in before removing it and relying on the MSD chip (set at a higher RPM)

Monkeywrench
02-03-2007, 10:33 PM
Are more vintage groups allowing roller rockers now? I know at one time they were frowned on. I've got some of Peter Dodds' 1.5:1 forgings lying around if I have to run conventionals.
Jeff

Jeff,

All but the most stringent allow them. I believe, but I'm not positive, that VSCCA on the east coast and and I think SOVREN on the west coast don't allow them.

swift6
02-05-2007, 02:21 PM
A foolproof but hard to find rev limiter is the Lucas rotor fitted to Lotus engines - set for 6500 RPM but adjustable if you have a distributor machine.

I often used one on my Twincam when I was breaking it in before removing it and relying on the MSD chip (set at a higher RPM)

FWIW... Dave Bean Engineering lists two different rev limiting rotors for Lucas Distributors. Both list a 7,000rpm limit.

billspohn
02-06-2007, 01:25 PM
FWIW... Dave Bean Engineering lists two different rev limiting rotors for Lucas Distributors. Both list a 7,000rpm limit.

Yeah - the original for Elans was set at 6500 but it is a really neat bit of gear with springs allowing a weight to slide out and hit a grounded tang, shorting out the ignition - very 'soft touch' in effect.

You can adjust the RPM that it hits the short out tang by adding or removing weight (in the form of little screws) to the moving weight. Heavier means it limits lower, lighter means it takes a higher RPM to get it out to the tang.

swift6
02-06-2007, 03:46 PM
They are precious too. They list for $35 and $72. For just the rotors. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

billspohn
02-08-2007, 04:30 PM
They are precious too. They list for $35 and $72. For just the rotors. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

But that's all you need in terms of gear- a fraction of the price of any other rev limiter you care to name.

I have found them to be very reliable - stick it in and forget about it.