Rev limiter for 4.0s

[ashmanjeepxj]

I found this:
Soft Touch Rev Control, Part Number 8728 from MSD.
Retails for $115. Probibly $60-70ish ebay sales. Thats alot more reasonable then the whole MSD-6 system.
http://www.msdignition.com/rpm_1.htm

What about the MSD RPM actiavated switch. The 12+ output could be sent to a coil power wire interrupt relay. Would cut power to the coil till the RPMs dropped, it would have some switching delays due to relay speed. probibly too hack, but would work.
You could hoop up one of thos rotating yellow caution lights activated by the RPM Switch, the "gettin-it" warning light.
http://www.msdignition.com/rpm_7.htm

 

[Slip Kid]

:laugh3: the red line is just the manufacturer's suggestion, and, it is 5.5

 

[doodahman]

MSD 6A --- no rev limiter

MSD 6AL --- built in rev limiter

MSD Offroad = MSD 6A with sealed circuit board for much more money.
(I believe they may make a 6AL Offroad equivalent for those who think their XJ is a submarine)

MSD makes an add-on "Soft Touch Rev Limiter" for any of their systems.

They also have one with a knob instead of the preset chips if you like.

The best combo is MSD 6A or 6AL with NOLOGY ignition coil. Works very good.



ps
Jacobs electronics may even be better than MSD it is a feedback computer ignition system (and it's waterproof) it also comes with coil and wires in the kit. It's a bit more expensive though.


-----------------------------------------------------------
Real Jeeps are built not bought..............

 

[XJoachim]

I'm going to put in a Mallory Hyfire 6AL in my XJ together with the stroker engine. It has a built in adjustyble rev limiter where you don't have to buy modules. :wave:

 

[Root Moose]

That may be true about the Jacobs but how much better can it be if you are returning it for a warranty replacement every few months?

Everyone I know that has run Jacobs has had an issue with it - most have either circular filed or sold off their Jacobs stuff.

r@m

 

[BigDawgz]

Hey guys....if anyone on here is running a soft touch 6-AL I have a couple of Chips left over from the last on that I had. I'm not sure...but I think the chips for the 6, the 6A and the 6AL might all be one in the same.

I know that I have the 7,000 and the 3,000 one. If anyone has a use for either or both of these gimme a shout and I'll hook you up. They're light enough to just mail in an envelope...I'd say. I might have others....but I have these in front of me right now...the others I'd have to go and look for.


Later
Aron

 

[CheapXJ]

cheapo redline control for renix 4.0L:

cut tabs off distributor.
rotate slightly at idle.
rev it.
keep rotating until ignition breaks up at desired RPM.
if idle breaks up, you're rotating it the wrong way.

this DOES NOT alter ignition timing.

what it does is limit how far timing can advance. timing goes too high (as engine RPM goes up, simple renix is just uses timing as a function of RPM) then spark breaks up.

 

[jjvande]

have you done this... and how might a performance computer(RENIX) be affected by this change. I would be interested in this mod if it was tried and true.

 

[Scott Mac]

:laugh3: the red line is just the manufacturer's suggestion, and, it is 5.5

Yea, it's only a suggestion, the actual red line is only a tick before something breaks on your motor.

 

[ashmanjeepxj]

cheapo redline control for renix 4.0L:

cut tabs off distributor.
rotate slightly at idle.
rev it.
keep rotating until ignition breaks up at desired RPM.
if idle breaks up, you're rotating it the wrong way.

this DOES NOT alter ignition timing.

what it does is limit how far timing can advance. timing goes too high (as engine RPM goes up, simple renix is just uses timing as a function of RPM) then spark breaks up.

I am all bout Twistin and Cutin stuff off upgrades!
Who has tried it?

I dont have the distributor in front of me, what tabs?
Would it still be water tight?

See if this pic works...?

 

[jeepkid2000]

what if you 4.0 doesn't have a dist. ? no cheap fix?

 

[CRASH]

Only Renix rigs don't have a rev limiter, anything newer than 91 has some form of spark limit, ususually at 5250.

CRASH

 

[Dr. Dyno]

I found this:
Soft Touch Rev Control, Part Number 8728 from MSD.
Retails for $115. Probibly $60-70ish ebay sales. Thats alot more reasonable then the whole MSD-6 system.
http://www.msdignition.com/rpm_1.htm

That's exactly what I need in order to bump up the rev limiter from the stock 5250rpm while keeping the stock ignition. Should be plugn'play. The 6000rpm plug in module is probably too high for me so I could buy a set of either P/N 8745 - Modules 5000/5200/5400/5600/5800 or P/N 87451 - Modules, 5100/5300/5500/5700/5900 to use instead. A set of modules costs about $27.

 

[Dr. Dyno]

Forget about the plug in module idea. The MSD-8671 4600-6800 rpm module selector is even better. It gives you an extra range of adjustability when plugged into the MSD-8728 soft touch rev controller unit.

 

[gradon]

Does the MSD override the stock rev-limiter/@ top speed?

 

[tealcherokee]

3 year old thread........

msd eliminates the stock spark control, completly

 

[Dr. Dyno]

Does the MSD override the stock rev-limiter/@ top speed?

Apparently not.