I'm having a heck of a time tuning my idle. Unfortunately its the first place I'm starting at, so this is gonna take a while.

I have had to lower my closed throttle VE soooo much I can't even comprehend what is going on. Believe it or not these VE #'s give me INT/BLM of 128/128. My bpc is 150. UGGGGGHHHHHH! My next post may be in the classifieds for all this prom hardware.

kpa 20 30 40 50 60 70 80 90 100
600 9.8 12.5 16.2 16.4 16.4 16.4 17 17 17
800 10.9 12.5 16 16.4 16.4 16.4 17 17 17

Will an adjustment in F30 make a difference here?

30lb injectors @45 psi, 383 ci, 52 TB, 8.5 cr, Sportsman II heads, cam 274/292 .488/.501. Base timing set to 0.00 matches constant spark ref angle. I don't know what else to do.

To keep my sanity, I may go FAST XFI.

 

Yep...F30 is an adder to both F29 & F29E. However, before you start there, I'd suggest lowering you BPC in F28. 150 seem a little high to me. Also, verify your IAC minimum air adjustment and check your fuel pressure at idle....if you haven't already done so. I believe my idle fuel pressure is like 38-39 psi since the fpr is vacuum referenced.

I know your frustration! I've been tuning/learning for 2 1/2 years and sometimes I feel like I don't have a clue!

 

Try setting your base timing to 6 degree like it is stock.

Adjust accordingly in your bin.

Have u tried tuning idle in OL only with a wideband? Whats it do than?

Have u flat out tried just starting over? I do it all the time(specially when something strange to me is going on), all it takes is missing one thing and whammo, its all messed up.

later
Jeremy

 

yeah a bpc of 150 is high, my 305 with 30lb/hr i have set to 119.00 although i'm still in the beginnig stages of tuning the $58

 

I just used 0 deg as base since that is what I saw in BBZB for spark ref angle.

Oh yea, WB OL tried that, ruined one NTK sensor, replaced it $185.00, you can read my post about afr's around 17-> 22:1 waaaayyy lean. So I tried using the ecm to help out. If I run a stock BBZB with 8 cyl changes, it runs at 60 int. I have started over 1000 times. My bpc using the 7749bpc calc utility from Craig's site gives me a BPC of 150. That is if I have 30lb injectors, rated at 43.5 psi, I am running 43.5 psi, bore is 4.030, stroke is 3.750. Granted the motor liked bpc 128 the best but it detonated on the high end. I have verified min air and IAC operation, all is correct.

Funny thing about the WB it says lean(3.09 volts) no matter how rich it is. I can assure you there are no vacuum leaks or exhaust leaks but I remvoved the WB after reading 17:1 on DM and there was soot all over it?????

I am an accomplised ASE Master certified mechanic with Advanced engine performance certifications and I can't get my own POS to run!!!!!!!!

I know my combo is not unique 383 iron head and 10psi boost. If anyone has some VE tables that might be close, care to share?

 

You might try setting bpc back to 128 and use F77 to add more fuel up top.

Also, the 90kPa cell of F77 affects ALL lower VE cells as well. If you increase the 90kPa cell above 1.0, it will add to all the non-boost cells in the F29/29E tables. Similarly, if you lower this cell, it cuts fuel in those tables. This bit me a while back.

 

Have you tried the o2 constants?
I suspect with your low CR and that size cam that your low rpm ve is low. And depending on the lsa of the cam. You may need to move the o2 constants to allow for some o2 getting into the exh at overlap. The always lean is pointing at this.

 

Z69, Haven't tried o2 const as I don't know which way to go. Lobe seperation is 113. Cam specs for intake open-29, close-65
exhaust open-84, close-28.

Lean on WB like you wouldn't believe 18 or 20. But the motor is rich. Fouled one set of plugs this weekend. Burned 1/2 tank gas at idle.

My idle VE has to be at 16? Seems F'd to me. I'd like to work on O2 const, do have any suggestions on which way to go?

 

I'm running a 355, iron Vortec heads, slightly smaller cam than yours w/114lsa, Edelbrock MPFI intake, 33lb injectors @ 45psi and a Whipple 2300AX blower. I was running 11psi boost but have recentely dropped it down to about 6.5psi. Here are my VE tables (F28 & F30 are same as stock BBZB):

 

I don't trust INT and BLM on 58 myself. If I am correct there is only 2 cells for it, open and closed throttle. To me is useless. I go off o2 combined with what does the engine want.

Of course I am still playing with the $58 on the syty platform, soon to be on a v8.

 

89C2500, I can't get close to those numbers for VE. Int will be at like 60.

I said screw it and loaded a stock AUJP into my romulator, removed vats, turned the fan on properly and hit the key. That rotten SOB fired right up an ran! It ran way better that any $58 yet. WHY???? INT/BLM was 130 ish whereas the $58 was 60. WTF? The AUJP was bone stock on my 383 with 30lbers. $58 has to be adding bunches of fuel somewhere. But where? Ve tables are real close to eachother.

I am becoming concerned that I may gas wash my new motor if this type of behavior continues.

FWIW map KOEO is like 2.34, so that is correct, TPS .54, temp sensors are in proper range.

Does anyone have a boost patch for 8d?

 

At this point, if I were you I'd try as 3.8TransAM suggested.....start over with a fresh stock $58 BIN. All I'd do is set it up for 8 cyl and your base timing. Re: timing...I'm surprise you can run it at 0 degrees advance...there's no way I can get mine to idle properly at 0 degrees base timing.

FWIW....I've done the "start over" routine several times as well. Also, I was gettting lazy with my emulator and not power cycling the ECU between BIN changes and that really fouled things up a couple of times.

You really need to bring down your BPC from 150 to 130. I know you said the WBO2 was real lean, but I'd be willing to bet it's just operating outside of it's normal operating range and giving you false readings. With the VE tables I posted, my WBO2 tracks fairly close to commanded AFR.

Good luck...

Oh...if you'd like a copy of my bin to compare, PM me and I'll send you a copy. Of course....it is a "work in progress"!