kbracing96

iTrader: (26)

I was, I could probably set up a switch to run the meth on full during staging, but that would be kind of a pain, but Dusty's idea of use PE to add fuel in the "stall" area sounds like a good idea to me. Maybe 10:1 in the 1500-3000 range?? I will have to give it a try.

Wilde Racing

iTrader: (26)

I go pretty fat in A/F, while "stalling" mine is alwas 10:1, it is a bit of an art to get the timming of the P.E to stop adding fuel the second you launch....... I'll post up a screen shot of mu P.E table and a scan of a 8 psi of boost stall with a stock converter.......

cablebandit

iTrader: (37)

add timing on an auto to help spool. If not it will make it lazy on the launch. Quicksilverado has gone 1.65/1.68 (i forget which and I was driving ) and thats with no timing reduction. I will add more next time out. His truck did this on a art car 2800 stall with 2 step. I found this to be true on my own f-body...stick likes low timing to stall....auto HIGH timing...much more than you would think

jcfreak

You could also command PE to come in sooner. I have cut 1.65 60fts on a reflashed stock stall at 2500rpm. I have a 2800 Precision now. I left friday night at 2400 on it and ran a 1.74 60ft. Track couldn't handle the 653tq or my tires and suspension couldn't.

vanillagorilla

iTrader: (1)

Yeah, using the PE does sound like a good idea, even for me. My *** is too cheap to justify spending $265 on a 2 step, so if I could just add enough fuel while reving, I might be able to get a few psi. I'm sure the engine will sound like its drowning though. I could actually use the VE table to faten it up since I'm basically reving in neutral while at the starting line. That way when I yank the clutch to launch, I'd be in a completly different cells. I could do the same with timing too. Hmm...

Wilde Racing

iTrader: (26)

I have tried this. I think it will work with the spark, I've not done that yet, but My engine did not like seeing A huge section of the V.E table raised. Normal driving I hit a large section of V.E cells (75 KPA x 5600rpm) But the is a huge section that could be used for brake stalling (100 KPA x 210 KPA x 2800 rpm (or what ever your desiered stall speed) The problem I had was getting to that 100 kpa without rolling...
So I did this

I had the problem of building boost, I could brake stall and only build like 1 or 2 psi, or about 85-95 KPA, I was only reving up to 1800 ish rpm.

I set my P.E table to 1.0 acroos the board. Retuned the B.E table and V.E so that I was free of the P.E table for tunning. Now I did have a bit more tip in K.R, but it all went away once I retuned the P.E. I also had to lower my P.E enable threshold down way low I also would have to lower my MAP threshold.
This is my P.E enable set up.
MAP at 60 kpa
Map hyst at 5 kpa
Delay Torque at 0
Enable torque at 0
Torque hyst at 0
P.E enable TPS (cold)I set the at 30% from 0 to 1200, then 20% from 1600 to 7200.

I plaid with the enrich ment rate quit a bit, but It still needs more. here is a screen shot.



So how did it work??
Here are a few screen shots of a stock 4l80e converter stalling up to 2800 rpm. now If you look at my wideband you will see It's at 10:1, which is were I want it, until I release the brake. Then I want it to go to 11.5:1 ASAP! I still need to work on that and yes That little bump in the RPM and Speed in the first screen shot, is my nasty 4wheel hope launch. I hit 42, then it drops down to 34 mph. lol

vanillagorilla

iTrader: (1)

I played with it last night and I was pleasantly surprised. I was able to build a fair amount of boost in neutral. I didn't write a tune or anything, but playing with the tune via the scanner netted me 4-5psi at 4500rpm. Again, this is in neutral (or in gear with clutch in) without a boost controller and NO load on the engine. I commanded an 8:1 AFR and had the timing set to 0*. It ran surprisingly well for being so rich, but it obviously didn't want to idle.

For us few manual turbo guys this might be a good option, especially if you don't want to spend money on a glorified rev limiter. Or if you are using a 2 step then full boost would be easy. I'm going to see if I can't alter my VE table and main spark table from 2000-4500 rpm in the neutral rev cells to replicate the results. It will be a track only tune though.