RE: pcm controlled nitrous

[Scott Parkhurst <ScottP@mcmullenargus.com>]

Switch to decaf. Most nitrous systems use an arm and fire switch, based on
fuel pressure and WOT. The programmable systems allow much more accurate
tailoring of the nitrous curve, but you've still got to be at WOT for them
to enable and operate the computer program. You wouldn't want to half-ass
this setup, as nitrous and fuel ratios must be kept constant (and a little
rich) to ensure no damage occurs to the engine. I setup a system like this
on a 99 TA/LS1/4L60E, and it works flawlessly on both the dragstrip and the
road race course. Once the throttle is at 100 percent, the computer begins
the program, waiting .2-second, starting the nitrous flow at 65 percent,
then going to 100 percent within another.25-second. All of these numbers are
variable via the NOS programmer. The car has all SLP bolt-on suspension
goodies and Eibach spring/shock upgrades, and 18-inch wheels with Toyo
Proxes tires. When the juice hits coming off a corner, you can't feel it
shock the tires, so they stick. You do feel the dramatic addition of 100hp
in the straights, and I went through a 12.5-pound bottle in a single
15-minute session at Buttonwillow (CA) raceway. Too much fun! Safe, sane,
and serious. 

Scott Parkhurst
Tech Editor
Popular Hot Rodding Magazine

> -----Original Message-----
> From:	Kelly Parker [SMTP:bigblockfw@hotmail.com]
> Sent:	Friday, May 19, 2000 10:36 AM
> To:	gmecm@diy-efi.org
> Subject:	pcm controlled nitrous
> 
> While I was gettin' hopped up on coffee this morning I began to wonder if 
> there was a way to control nitrous injection with the pcm.
> 
> What I'm thinking is......As I recall the commercial nitrous "controllers"
> 
> allow you to set when and how long the gas is injected.
> Since the EGR valve wouldn't fit in my engine compartment :-) I removed
> it. 
> The control is still in the pcm along with the wiring, The pcm allows for 
> egr min RPM and max RPM, it seems to me you could replace the EGR solenoid
> 
> with a nitrous solenoid. Since nitrous has an "arm" and an "inject" switch
> 
> (arm is a toggle switch, inject is a momentary)
> it seems like you could just switch off the toggle to keep it from blowing
> 
> your shorts off when you were just cruising. When you wanted to hurt 
> somebody just arm it and go.
> 
> Has anybody tried this?
> Does it make sense?
> Should I switch to DECAF?
> 
> Kelly
> 

> 
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