The positive reviews here have me looking hard at a 123Ignition dizzy replacement on my '73 2.0 w/ stock D-Jet.

But, the version they offer for the 914 that's compatible w/ D-Jet (123\PORSCHE-4-R-V-IE) has a fixed 8000 rpm rev limiter.

The thought of my motor turning to shrapnel at 8000 rpm is a just tad bit worrisome.

Ed at 123 Ignition said that the OEM rev-limiting rotor won't work in their dizzy, and suggested an aftermarket stand-alone rev limiter. But, I'm not too enthusiastic about adding an extra box at additional expense, just to limit revs.

Has anyone here used the 123Iginition w/ D-Jet? What did you do to limit rpm? Anyone just run without a rev limiter?

Thanks.

Yes, many of us have. Works really well.


Nothing. Just drove it, why?

Seriously, is not having a rev limiter a real worry? I don't know that anybody here using the 123 is that worried about running too high on revs or has had a problem. I mean, I'm not racing or anything, but I rarely get too much above 5000.

I dunno.

Maybe I just shouldn't worry about it...

Ok, then I wouldn't let that stop you if you're otherwise interested in buying one. It's pretty solid

Not 100% but think the stock rev limiter creates a ground which to some electronic modules is instant death as it becomes a short,if the unit has no polarity protection.
T4's don't make huge rev's in the normal driving range and don't need to if stock,really they run out of puff under 5K,I wouldn't worry.

You want no more than a 6K redline and never use a limiter as a shift indicator.
Depends on the cam but torque drops of at 5400 rpm with most cams, some hotter street cams it's about 5600.

Thanks. I was more concerned with somebody over-revving the engine accidentally and thought the rev limiter would be a valuable (essential?) safety valve.

I do know how to drive, after all.

How would you accidentally rev past 6K?
A rev limiter won't save the engine from a money shift (typically 5th to 2nd) since that is a mechanical over-rev and not caused by the gas pedal.

Only way I see this as possible is racing the car (AX or track) and not paying attention to the sounds your car is making.

Zach

Mis-shift. Think you have it in gear and plant the right foot, ain't in gear.

I agree it would do exactly nuttin' for a money shift. Scattered the top-end of an SR20DE at Road Atlanta doing that...

Never say never, with a high performance balanced engine it's a lot easier than you think.
I hit my rev limiter a couple times on my 2600cc T4 bug this last season. I haven't hit it yet on my new 3.0 /6 but I came pretty damn close. I wouldn't drive a performance engine without one.

Mr. Hyde's engine, a 2.3 (80x96mm) balanced with healthy breathing from 44mm webers and a tangerine 1-7/8" header, he had one of the cable linkage carbs stick WOT and it went BOOM. Pete from RD has a vid of the mishap, it only took a second before it granaded.
Mike was so bummed he sold me the car, in his case a rev limiter would have likely saved the engine.

On a stock or stock-ish engine you are much less likely to ever hit a rev limiter, as the engine just can't breath enough to get one into trouble.

I'm guessing that you don't have kids.