The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Racing and high performance (trucks haulin more than hay)

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 02-03-2009, 11:01 AM   #1
smoknbarrels
Registered Mail
 
smoknbarrels's Avatar
 
Join Date: Jun 2006
Location: Alberta, Canada
Posts: 513
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

:-)
smoknbarrels is offline   Reply With Quote
Old 02-03-2009, 01:20 PM   #2
Marv D
Registered Truck Offender
 
Marv D's Avatar
 
Join Date: May 2008
Location: hells training ground (aka Ariz)
Posts: 3,118
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.
__________________
Still playin with trucks, even at my age!

When you're dead, it's only a problem for the people around you, because you don't know you're dead.
.....It's kinda the same when your STUPID.


I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.
Marv D is offline   Reply With Quote
Old 02-03-2009, 02:18 PM   #3
smoknbarrels
Registered Mail
 
smoknbarrels's Avatar
 
Join Date: Jun 2006
Location: Alberta, Canada
Posts: 513
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?
smoknbarrels is offline   Reply With Quote
Old 02-03-2009, 05:55 PM   #4
regan wilson
Senior Member
 
regan wilson's Avatar
 
Join Date: Mar 2008
Location: tyler texas
Posts: 1,532
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 .
__________________
NHRA Super Street 469C
It only runs 10.90 at 156 mph
regan wilson is offline   Reply With Quote
Old 02-03-2009, 06:38 PM   #5
smoknbarrels
Registered Mail
 
smoknbarrels's Avatar
 
Join Date: Jun 2006
Location: Alberta, Canada
Posts: 513
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!
smoknbarrels is offline   Reply With Quote
Old 02-04-2009, 02:36 AM   #6
71chevytruckguy
Registered User
 
71chevytruckguy's Avatar
 
Join Date: Jul 2005
Location: Kernersville, NC
Posts: 599
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.
__________________
its a work in progess.

71 c-10 lwb, in the middle of frame off restoration.

69 c-10 swb, drag truck, 406 sbc, balanced, comp 292 cam, ported, polished, gasket matched, and bowl blended pro comp 210cc heads, 2.02/1.60 ferrea valves,1.6 roller rockers, re curved hei with msd 6al box, 2-step rev limter, accel 300+ wires, ported victor jr intake, holley 750 double pumper carb, dynomax 1 5/8 headers, 4 spd munci m-20 with super case and iron midplate, mr. gasket vertigate shifter, 5.38 pro gears with full spool, 33 spline moser axles and c-clip elimators, line-loc, 5 gal fuel cell, holley blue pump.
7.807 @ 88.37mph 1.60 60FT

80 g-20 van, tow rig, cammed 305, th350, 10 bolt

88 jeep wrangler, dd, 258, ax-15 swap, 4.5" lift, 33x12.50's, lockers, 3.55's

Last edited by 71chevytruckguy; 02-04-2009 at 02:37 AM.
71chevytruckguy is offline   Reply With Quote
Reply

Bookmarks

Tags
msd 2 step, msd box, rev limmiter


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 06:55 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com