dbs1. it's figured out. i just logged my updated tune today, sweet, hav'nt disected the file yet to see what he did but it's coming out awesome. was a little lean on the first try but still had little or no kr. i know we upped the timing a little and adjusted for the fuel. feels better and the o2's and ltft's are in line now. don't know if you're having any major probs but for me this is major improvement. before ,everytime i needed to floor it to pass someone i did'nt know if i was going to throw a code, a rod, or have a coronary because i was so pissed off. from my experience i would never recommend anyone trusting their motor to those electronics. do yourself a favor call allen when your ready. i believe he has a package in the works for the whipple guys, with the inj's and tune. give him a call and ask, he's very easy to work with and i'm sure he would be more than happy to give you suggestions on inj size boost limits and whatever other info you might need. gotta go find that 740il that beat me a couple weeks ago, i know i can smoke his a$$ now hehehehe. btw allen says tuning for the 7lb pulley won't be an issue.

 

hey guys, regarding the boost a pump. was looking at it today, it appears to have an independent power supply but it does have a lead going to the whipple computer. is it worth probing to see what's going on with it with the computer disconnected ? or just take it out. last time i checked the pressure i believe i had the computer offline, and i had 61+ psi at idle. guess i could wire it back to stock and see if there are any issues. this is the last of the electronic junk left and i figure i might as well get rid of it if it's not necessary. truck is running great, but, since the last tune i'm getting a abs light and a brake light every other time i start it and it stays on until i shut it off and restart, could be coincidence. i'll scan the codes and see what's up. e

 

I'm old and mechanically dangerous, so what I'd like to see when you get things completely figured out, is a complete step by step, starting with what injectors to use (and part #)-additional fuel pump (if used) and how to bypass the whipple jive electronics, to go with the nelson tune.

Did you guys also go to the 160 t stat? I put my 160 back in today, and it does the old tail wagging of the temp indicator again, but at least it has'nt set off any codes (yet).

I also put on the smallest pulley I have (2 3/4) and my boost went from 5+ to 7+, even though I was expecting another pound or so, but I'm having to use the same serpintine belt as the 3 1/8 pulley because the next smaller belt I could find was an inch smaller and I could'nt get it on, so a half inch smaller belt may give me another 1/2 pound of boost without the slop I currently have, which should work fine till the weather cools.

Bt the way-I did get the throttle body replaced via my extended warranty, and as yet I have not had the idling issues I was having rear their ugly head, so hopefully that issue is solved.

Keep us updated on your success! Thx!

 

ha ha, i'm starting to feel old and i usually know just enough to get myself in trouble. seriously though, i'd really give allen a call. someone else can chime in, but i'd say a lot of guys are running head mods and cams along with a supercharger and the 43lb marine inj's are supplying enough fuel. the floating temp gauge is from the whipple "lying" to the pcm, telling it it is hotter than it is so it keeps the timing advanced. mine did the same thing. allen will modify the tables that control when it pulls spark due to lower coolant temp, and you can have you temp gauge back to normal. here's how to get rid of the electronics; if your wiring harness coming out of your pcm has a plug in between the pcm and the whipple computer, they should have supplied you with a small plug to return the wiring to stock without undoing the splicing. if they did'nt supply you with one, call them and get one. if you don't have a plug in between, you'll have to pull the pcm and undo the slice/tap. i can fax you a wiring diagram if it's the same as mine. then do the solonoid bypass discussed earlier in this thread [easy]. you'll want to have your tune already because if you don't it will run like crap, and you'll pretty much want to do all this at one time. depending on how you do the tune [ls1-edit, pcm swap, or drive to texas] install times will very. for me it was as simple as loading my new tune with edit [5 minutes], unplugging the harness and installing the bypass plug [1 minute] and bypassing the solonoid [20 minutes, if you have to scrounge around the garage for parts]. if you have to pull the pcm, that's only an hour. i had already installed the larger inj's, about 2 hrs if you've never done it before [don't drop the blue o-rings] and voila your done. like i said i think allen is coming up with a kit that includes the inj's, and if you need advice on installing anything i'm more than happy to talk you through it. allen does'nt work like most people i've dealt with, meaning he won't just send you the stuff and write you off once he has your money. he will continue to help you until you're satisfied that your tune is as good as it can be. i was a little sceptical at first that it would turn out as good as it has, but i have no reservations about recommending this conversion, and along with many other people on this site highly recommend allen nelson as a tuner. i'm sure another tuner can do it, but i know for a fact allen can. e

 

oh i forgot about the fuel pump. from what i've heard, the stock pump can supply enough pressure without the booster. if you saw my post i was asking about the boost a pump. if i have time tomorrow i'm going to pull it and check the pressure, and test drive it. i'll post my results. i may take the time to probe it and see if it is functional without the computer. i have plenty of pressure now but i don't know if the booster is bumping up the voltage or just passing it through, but you should know soon.

 

dbs, i was looking at my belt setup yesterday. i remembered it has a lower pulley adjustment [slotted] in addition to the tensioners. do you have that all the way to the right ? just a thought in case you did'nt notice to help get rid of that slack. e

 

I'll have to go check on the pulley adjustment, as no one has the 1/2 inch bigger belt that I need.
I'm thinking also, that my sc that I bought in July of 01, had just discontinued the use of the boost-a-pump program. When running 7+ lbs of boost my fuel pressure gauge says 65+ lbs, but when recently checking the tranny, the guys told me that it was throwing a code(s) for running lean, which from the last engine build is a big no-no.
You could fax me the info you mentioned to 928-367-1454, and I'm going to print out this whole set of posts for tuning the sc with Nelsons setup.
I may wait until he's got the whole package put together as a kit, and then jump on it.
Many thanks!

 

I'm not sure if we have the same whipple setup or not. I've pulled the one lower pulley in front of the t stat to put on the 160 t stat, and it does not appear to have any adjustment. I'm not sure what other pulley may have some adjustment, or if you're talking about the spring loaded tensioner?
I'll need some more input (if we have the same setup). Thx!

 

i have a single belt purchased late last year, 2300axo compressor. the compressor has a thick plate that mounts it. from the top down, compressor pulley , tensioner pulley, the one i'm talking about is next, then the crank pulley. the one i'm talking about is mounted in a slot on the plate, it has a 3-4" slot. mine is in the center so i can move it either way for a smaller or bigger belt or pulley. i said earlier move it right but it's left to tighten belt. i have a 6.0. they may have had a different mounting bracket for your truck, which is what ? . i see you do have the same problem i did, i mentioned it earlier but you did'nt confirm. the low o2 signals are from the whipple computer, i can't for the life of me figure out why it does that but it does i have it logged. you may or may not be lean, you have no way of knowing with that computer on there. unless you have an exhaust gas analyzer. 65 psi is fine for fuel pressure. does yours even have the solonoid on it ? i'll email you a picture of mine to see if we're on the same page. e

 

I have a 2001 C3 with the 6.0. I think since I still have the fan shroud off, I'll just pull the belt off, and pull off a few of the pulleys and see what adjustment there is to be had.
Thanks for all your help and advice!