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-   -   2 step rev-limmiters.. do they lean you out?? (https://67-72chevytrucks.com/vboard/showthread.php?t=326884)

smoknbarrels 02-03-2009 11:01 AM

2 step rev-limmiters.. do they lean you out??
 
my truck is a standard, and when I want to launch I will be using a 2 step rev limmiter (the MSD 6AL2 i think is the part#). I want to attach the switch to the clutch pedal, this way when the pedal is pushed in it knocks me down to my low revs/launch rpms, then when I release the clutch the rpms can go up to 6500 (max 2nd step)
so I figure this way I can just hold my right foot to the mat on the gas the whole time, even when changing gears... will this work?? I thought it would give me dependable launches every time.?
or will this lean me out if the carb is wide open and rpm's low.

I need experience with this

:-)

Marv D 02-03-2009 01:20 PM

Re: 2 step rev-limmiters.. do they lean you out??
 
Your going to be using a brake to hold it steady at the line, even with a manual I'd put a line lock in it and use the line lock button for the low side rev limit. The clutch deal just sounds counter-productive. One: you will have to have the clutch depressed to the stop (switch) to activate your two-step. Much better to have a line lock as even the spinning mass in the clutch can cause the vehicle to creap forward out of the beams. So how you gonna stop that??? 3 pedal launch??? (gas, clutch and brake). CUMBERSOME and you will have a hard time being consistant that way. A line lock is also very handy on the street for those steep hill starts, AND you can put a little strain against the driveline before the lauch to keep from hammering the gears and U-jooints from a slack position. Just do yourself a favor and put a line lock in it to hold it steady at the line, and connect your low side rev limiter to it. you'll be MUCH happier.

smoknbarrels 02-03-2009 02:18 PM

Re: 2 step rev-limmiters.. do they lean you out??
 
yea, i am putting in a line lock, but never clued in to wire it to the rev limmiter...

what about my lean question.. would it work efficiently to hold it to the mat keeping all 4 barrels open eventhough its only running 2000rpm, or is that gonna hurt the motor?

regan wilson 02-03-2009 05:55 PM

Re: 2 step rev-limmiters.. do they lean you out??
 
You will be fat not lean becuase the ignition is dropping cylinders which in turn means unburned fuel . I have always been told dont rev limit or 2 step under 3600 rpm ( not good for the motor ) . I would also set the high side of the rev limiter 300 abovethe shift point ( and hit the shifts of course ). You should talk to a stock eliminator or super stock racer if you really want to know what to do . I hate to say it but you could learn something from a fast Mustang stick racer if you know one .

smoknbarrels 02-03-2009 06:38 PM

Re: 2 step rev-limmiters.. do they lean you out??
 
yea, u're right, I checked with MSD and they recommend keeping it above 3000 rpm at least. I'm not yet sure where I'd be releasing the clutch at.
thanks!

71chevytruckguy 02-04-2009 02:36 AM

Re: 2 step rev-limmiters.. do they lean you out??
 
nice to see some else running a stick. the way i was thinking about doin a 2 step in my is having a button to activate the low side on the steering wheel near where your left hand is. then run the line lock on the stick. already have the line loc set up and it made it 1000 times easier than tryin to 3 foot it. Chris.


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