• Registered: 2010-02-22
  • Posts: 84

Topic: does rev limiter count towards $500?

HI, 

I was wondering if a rev-limiter doesn't count towards the $500 in some little loophole about safety or driver info or something.

The one's I've seen out there run from $50 to $150, and ebay doesn't have much in the used category.

I don't want to change the car's ignition, just add a rev limiter in addition to our Ebay-special tach / shift light.  I'd rather not have the shift light at max rpm, and would like to run a rev-limiter as a backup

thanks!

  • Registered: 2009-12-09
  • Posts: 53

Re: does rev limiter count towards $500?

We found one on ebay for about $36....

250 GTO
  • Registered: 2010-02-22
  • Posts: 84

Re: does rev limiter count towards $500?

I had also found one, got a good deal on it for $30...but too bad it doesn't work with our application

  • Marc
  • Lemons Staff Stalker
  • Offline
  • From: Fort Wayne, IN
  • Registered: 2009-10-06
  • Posts: 1,378

Re: does rev limiter count towards $500?

bikesandcars wrote:

HI, 

I was wondering if a rev-limiter doesn't count towards the $500 in some little loophole about safety or driver info or something.

The one's I've seen out there run from $50 to $150, and ebay doesn't have much in the used category.

I don't want to change the car's ignition, just add a rev limiter in addition to our Ebay-special tach / shift light.  I'd rather not have the shift light at max rpm, and would like to run a rev-limiter as a backup

thanks!

you're just not being creative enough. if you have a shift light already, hook up a normaly closed relay to the shift light output inline with the ignition coil power. blam, instant rev-limiter.

just make sure you don't have cats on your car, cutting ignition only will quickly overheat/plug catalytic converters

  • Registered: 2010-02-22
  • Posts: 84

Re: does rev limiter count towards $500?

Thanks for the tip!

I was thinking that if I did that the tach signal would die, cutting the light (closing the relay), and it would sit there and rapidly cycle until the revs dropped...which didn't sound ideal.

  • Marc
  • Lemons Staff Stalker
  • Offline
  • From: Fort Wayne, IN
  • Registered: 2009-10-06
  • Posts: 1,378

Re: does rev limiter count towards $500?

bikesandcars wrote:

Thanks for the tip!

I was thinking that if I did that the tach signal would die, cutting the light (closing the relay), and it would sit there and rapidly cycle until the revs dropped...which didn't sound ideal.

that's exactly what would happen. and that's exactly how a regular rev-limiter works.

  • From: Santa Margarita, CA
  • Registered: 2009-06-03
  • Posts: 177

Re: does rev limiter count towards $500?

I think a solid state relay would be better than a electro-mechanical unit, but that would work well.

Team Dai Hard Home Page

1989 Daihatsu Charade

djcommie's Website

  • bob-e
  • Ripened Lemon
  • Offline
  • From: Middle, TN
  • Registered: 2009-06-08
  • Posts: 265

Re: does rev limiter count towards $500?

Hmmm.  We need something like this.  The factory fuel cut is horrible.  Keep on thinking the car has blown up.  There are a bunch of cheap used ones on ebay

  • Registered: 2010-02-22
  • Posts: 84

Re: does rev limiter count towards $500?

I think I need more basic ignition research...

I could be wrong but I think a rev limiter on a traditional setup (non MSD type box) works by grounding the negative terminal on the coil to the chassis ground thus collapsing the magnetic field in the coil and preventing firing.

What it sounds like here is the opposite, actually interrupting the power. 

It may be better to put  an always off relay between the ground and the negative wire terminal on the coil that would ground the coil when fired no?

  • Marc
  • Lemons Staff Stalker
  • Offline
  • From: Fort Wayne, IN
  • Registered: 2009-10-06
  • Posts: 1,378

Re: does rev limiter count towards $500?

bikesandcars wrote:

I think I need more basic ignition research...

I could be wrong but I think a rev limiter on a traditional setup (non MSD type box) works by grounding the negative terminal on the coil to the chassis ground thus collapsing the magnetic field in the coil and preventing firing.

What it sounds like here is the opposite, actually interrupting the power. 

It may be better to put  an always off relay between the ground and the negative wire terminal on the coil that would ground the coil when fired no?

that's a good point. cutting the power may allow a stray spark to escape. shunting the ground will prevent that one spark event from escaping by just leaving the coil charged.

good call!

  • Registered: 2010-02-22
  • Posts: 84

Re: does rev limiter count towards $500?

http://images.google.com/imgres?imgurl= … s%3Disch:1

12 Reply by rockwood (edited by rockwood 2010-04-27 01:22 PM)

  • From: San Diego, CA
  • Registered: 2010-02-11
  • Posts: 156

Re: does rev limiter count towards $500?

Marc wrote:
bikesandcars wrote:

I think I need more basic ignition research...

I could be wrong but I think a rev limiter on a traditional setup (non MSD type box) works by grounding the negative terminal on the coil to the chassis ground thus collapsing the magnetic field in the coil and preventing firing.

What it sounds like here is the opposite, actually interrupting the power. 

It may be better to put  an always off relay between the ground and the negative wire terminal on the coil that would ground the coil when fired no?

that's a good point. cutting the power may allow a stray spark to escape. shunting the ground will prevent that one spark event from escaping by just leaving the coil charged.

good call!

Either way would likely work well enough for a rev limiter, since you only need a resolution of a couple of hundred rpm anyway, that extra spark or 3 won't cause the engine to overrev too much.

Either solution, however, would have the added bonus of throwing flames out of the exhaust on shifts, assuming your exhaust doesn't route all the way to the back of the car.

Keep in mind that a spark-only rev limiter might not be enough to keep the revs down on a white-hot turbo car running a fair amount of boost (not likely to last anyway for Lemons), nor will it help in a misshift (amazing how many people think it does).  Don't ask me how I know...