launch control for speedpro

[jwaller]

I haven't had any problem with blowout on the 6a. at least none that me or the guy who helps me tune can detect. I thought that since the digital 6al had a little more that it would do the job and save a couple hundred bucks. I've tried the ngk's and the autolites and had the best succdess with the autolites. I seem to remember john gerber saying he had a lot better luck with the autolites after he switched from the ngk after I told him. I haven't noticed that the gap heped or hurt whether i did it cdlose or wide. we were afraid that maybe that much power and boost (28 +) would eat em up but so far that hasn't been the case.

On the other hand I only want to buy one so maybe I should just splurge for the bigger one

the way I see if, I like things simple. less is more. so if I can put all the goodies in 1 box and keep it simple then thats the way I'm doin it. I don't like the idea of combining 10 different add on features and maybe intorducing a wiring problem that could be very hard to find and a major pain to fix....1 box, all the goodies, simple and clean

 

[EightSecV6]

If you ar eusing a F.A.S.T. system, you only need a Digital 6, it has one timing retard (not needed unless you are spooling with a clutch) and it has a 2 step rev limiter built in. You will need an HVC coil. You will not blow the spark out with this set up. I use it on my Buick with a PT98 and it works flawlessly. If you are using the stock ECM, you'd probably be better off with a Digital 7.

 

[Sy#26]

Launch control based on the MSD 6AL, basing it on boost, not rpms, isn't hard to do.

Need a Hobbs switch w/ very little hysteresis - Aquamist makes a nice one, on @ X psi, off @ X-1/2 psi.

Get one of the adjustable modules for the 6AL - or just use a 2k pot.

Datalog, running the rpms up against the converter. Note approximate psi vs. rpms - there is somewhat of a correlation. Pick the launch boost you want, set the module to slightly lower rpms than you get @ that boost level. Set the Hobbs switch @ around 2psi lower than desired launch boost (dunno why, but its too high otherwise). Wire the Hobbs in series w/ your launch switch.

Set the brakes, floor it w/ launch switch pressed soon as you're both staged; she'll come right up to the boost level ya picked & hold it pretty steady for a few seconds - mine tends to slowly fall past a few seconds, but haven't spent much time fine tuning it & toasting the trans. By the second light, you should be @ chosen boost. YMMV, etc.

 

[Turbo6]

So the hobbs switch is set to delay the 2step til you nearly reach the desired boost correct? I assume it helps reach the desired boost quicker? If so I will try this.

 

[Sy#26]

Yes, you'll reach your chosen boost as rapidly as your hardware will permit.Just using an rpm setpoint to launch, your boost will take *forever* to build up. Dunno about the two step rpm limiter, I just use the 6AL for launch & ultimate rev limit in the ECM chip. If you get the rpms and boost levels nicely coordinated, she'll be as smooth as a NA car staging. If they're mismatched somewhat, there's a nice *boom* before that nice stutter begins. Harmless (I think), but sounds like something bad broke.

 

[100in6]

sy 26

i've been tryin the launch control and it seems to run slower. I'm thinkin that maybe I'm loadin the motor up with gas while it sits there stutterin before I let go of the button.

whatcha think

les

 

[Sy#26]

Les -

I have no clue whatever about the launch control w/ a truck of your specs. You're probably good enough @ launching, going slower w/ it might be true. I'm an older doof, and just use it to get fairly good (1.72x) & consistant launches - reaction times just aren't what they used to be.....too damn much to keep an eye on while staging, for me it works well. Seems to me, loading the engine up w/ gas doesn't happen, as cylinders are cut randomly, and as soon as you releare the button, just takes two revs of the engine to clear & ignite everything. Humm, how about a constantly lit sparkplug in the turbine inlet to burn all that wasted mixture.....

 

[ed hess]

should only be few weeks and i will post how the rev limiter in the dfi 7 is working.

actually going to put it in immediatley after i get some new base runs with this tranny and 3k stall converter.

I beleive , ken will correct me, that the dfi 7 rev limiter will controll the timing and the fuel during rev limiting launch.

ed


i think i will be the 1st on this board with a dfi7.

 

[EightSecV6]

Just using an rpm setpoint to launch, your boost will take *forever* to build up.

Not on "all" setups, If your convertor is loose enough, you can for example set the 2 step at 4000 rpms, plant it on a transbrake and your boost will get where you want it rather quickly!!
My car has a 274" V6 in it with a clutch, I set the 2 step at 6000 (using the clutch sw. to trigger it), I also use an Inovative controller set at 16# of boost. I get from idle to 16# in just about 9 tenths of a second. I guess it all depends on your combination as to what will work best.
Bill