Rev Limiter

[Campbell]

I bought a Petronix rev limiter and I am trying to figure out where to mount it - I think I should try to mount it inside the car.. any suggestions on what works best?

Thanks

[racer_tim]

Rev Limiter on an IT VW? Never heard of it. I thought that the VW had a built in rev limiter. The fact that the valves will float before you break or bend anything.

Are you worried about zinging the motor because of missed shifts?



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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

[Campbell]

Tim,

Yeah, missed shifts and whatever. I just built this engine and I really want it to last a season or two, this will help me sleep easier I guess. I run a JH engine, do solid lifters float? thanks

[Knestis]

A rev limiter won't prevent mechanical over-revs - like getting 2nd rather than 4th on an intended upshift.

I ordered a custom chip for my MkIII and had them put the rev limit at 7500 where it would be pretty much out of the way...

K

[racer_tim]

I didn't think that you could get anything over 8,500 rpm with stock valve springs.

That's what I meant by "built in"

I've never had a problem with the top end, it's the #3 rod bearing that is the first thing to go when you don't have decent oiling.

I would also head to the dyno to see where your optimum shift points are.



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Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit
http://linerud.myvnc.com/racing/index.html

[Dave Zaslow]

Had a Rabbit GTI. My MSD rev limiter lived outside on the DIS plate for 8 years. Made it easy to change the rev limit pills as well. In my experience it is very hard to blow up a JH engine on over-rev, mechanical or not. It is not hard to screw up the clutch when you do this though..... If you are using a Sachs. Talk to Stu at BSI to make sure you have a Sachs with the old/correct number of straps, rather than the one used on the newer part #.

Dave Z

[Bill Miller]

Originally posted by Dave Zaslow:
...In my experience it is very hard to blow up a JH engine on over-rev, mechanical or not...

Dave Z

How right you are Dave. I know this first hand. Had one of the linkage rods (the one that selects the gate) pop off on my Rabbit GTI. It happened at Summit Point, on a restart. Got a great jump comming out of 10, and when I went for the normal 4th->5th upshift, it went right back into 3rd, w/ me mashing the gas. Was only there a split second before I pushed the clutch in and let off the gas, but I'm sure it saw every bit of 8500, if not more (shifted @ 6500).

The motor was fine, and went on to run 2 more seasons. It was still running fine when I sold the car.



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MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608

[machschnell]

I have a few hours of video of a guy running an ITB Rabbit that constantly was hitting b/t 8-9k RPM just to avoid having to upshift for a particular part of the track.

I know I've floated the valves on my Rabbit plenty of times, no harm done that I could tell, 'course there's no power there, but it's good to know the motor can take it.

PJ

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83 Rabbit GTI - future ITB

[SamITC85]

It is extremely difficult to blow up the VW motors. During a start at a race at Lime Rock I was in 3rd at about 6500 RPM going to shift into 4th, well I accidently pulled it into 2nd and nothing happened. However, it can be done. A friend decided that he would wait to shift into third gear at NHIS at the top of the hill during his drivers school. He made it through three 20 minute sessions before it couldn't take anymore.

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Sam Rolfe
TBR Motorsports
#85 ITC VW Rabbit being converted to LPHP
#85 GP Scirocco

[Mark LaBarre]

I put an MSD 6 AL with adjustabbl rev liniter in my old ITC Scirocco, mounted right next to the drivers seat. I didn't want to bypass the fuel pump relay, so I had to put in a tach adapter to keep the fuel pump relay running off the tach signal.
Worked great, but I didn't really need the rev limiter feature.