yeah, the piggyback in theory seems like a good idea, at least it did when i bought it. it seems like the fueling/spark is way to much for it to compensate for. mine had a bad stumble at 3700-4000 rpms, not to mention it showed very very lean on the logs, though i know it could'nt have been anywhere near as lean as it showed or i'd have melted my pistons. what engine do you have ? must be small to run 30# inj's. you'll feel like you bought a new truck once you do the swap, i did. hopefully you're planning on a tune when you do it, it won't work without it. so anyway, did my own mod on the tune today. backed the timing out in the wot section of the table, i can semi aggresively accelerate to 100 % throttle with no kr. this truck is getting scary fast [for a lifted 4x on 35's] i can't imagine what the 10+ psi intercooled, nitrous trucks are like. still having a problem with kr when i floor it while moving and it down shifts, it's killing my timing to 3.5 to 6 degrees. thats half of what i'm doing when i take it easy. e

 

hope so most guys are running 43lb marine inj's for the boosted apps. but i'm close to sea level. if you have edit, allens the man. even if you don't you can do a pcm swap. it's worth the money. i'm sure you know you need to change the ifr as well as the timing, or it'll run like crap. good luck, e

 

www.nelsonperformance.com or call him, his # is on the site. initially you might want to call and straighten out whatever questions you might have. also you'll want to coordinate your swap so you don't have any down time on your truck. ask allen about your proposed inj size. the pcm can compensate for a pretty wide range of altitude and temp changes. tuning is always more critical for boosted applications, but i'm sure allen can handle it. e

 

etc, on my 2 pulley whipple, there's wire that goes from the whipple computer to the bottom of the compressor. I think it was called active control or something. I unplugged it, good idea? i tried to totally disconnect the whipple computer, but, the boost-a-pump is hooked into it. with it disconnected, the truck can't run unless i splice the fuel pump wire back together. I guess I'll leave all the extra crap under the hood for now.

 

ok, so now we know you have the "active boost control" that's the electronic bypass solonoid we were all discussing earlier in this thread. go back and read that again and look at the picture that was posted. if you just unplug it it should limit your boost to about 2 1/2 pounds. your boost a pump is hooked up differently than mine, you should be able to find the hot lead for it and just hook it to another ignition triggered hot. pull the cover off that big black fuse box under the hood, actually you have to take the whole cover off, i just went and looked at it. there is a large threaded lug there that's were my power is hooked. i can fax you the couple install pages that deal with the boost a pump if you give me a # to send it to. or just do this; follow the lead from the b.a.p to the engine bay, it should go to a relay, coming out of the relay should be a hot and a ground, the groung should already be grounded and i assume the hot is feeding off the whipple. relocate the hot to the lug and it should work. if any of this does'nt look like what you've got don't do it, i would'nt want you to short anything. let me know what happens. e

 

http://james.jaguar.net/coontoot/wefi.jpg

hey,, what the heck is that big solonoid lookin thing on the right side of the picture? mine has no such thing. the one wtih the 5 wires coming out? i want to dissconnect mine bypass valve, but mine looks alot different

 

alright guys, here is 3 pics of my setup. help!


]

 

Just do this and you are done. Pretty simple huh? I think I overthought this a long time ago. Well this is what the forum is for You will have to retune your fuel table PE vs. RPM **BEFORE YOU WOT IT WITHOUT THE WHIPPLE COMPUTER.
For just a quick guess to kind of get you at least in the area of where you shouls be running a/f wise, multiply the 1200 and up rpm cells by 115% This will raise those fueling values up 15% of their previous values. That should get you at least on the richer side so you don't go lean under boost. **This is just a rough area though. You may need more fuel so check things before you hold your foot on the throttle for a full 1/4 mile run.

 

is that picture the newer setup or the older 2 pulley setup? I have the older setup and it doesn't look like that. I can't make heads or tails of that picture or the one earlier in this thread. here's a pic before the install.

 

Damn, there is alot of reading in this thread! I was having a problem with the by-pass bleeding off boost as the RPMs were climbing. I'd see just under 7# and then it would keep dropping back into the 4s. Disconnected the by-pass a few months ago and now see a solid 7.5-8# of boost. It's a whole different truck!




2002 8.1 Silverado HD - Full Throttle lift, 37" tires, Comp Cam, TOG headers, Volant induction plus more!
2002 8.1 Suburban -Intercooled Whipple supercharger, 22" wheels/tires + more - 407hp/558 ft-lb torque at the rear wheels - 13.93 @ 95.79 MPH

www.tbyrnemotorsports.com