Locking MAP at idle?

keithmac · Post by **keithmac** » Mon Mar 20, 2006 10:11 am

Hello all, just been thinking about my idle fueling (as you do!). My map varies between 58 to 65 ish at idle mainly due to the cams, I was thinking of locking the MAP value at idle so the fuel calculations don`t swing about as much. Has anyone else tried this (suppose it may come under hybrid alpha-n?), I was going to lock the MAP at 62kpa with the TPS below threshold and rpm below 1100, this would also cancel out any effects of the PWM idle valve which by it`s design affects the MAP value..

Running MS1 and extra 029J, any comments welcome.

TT350chevelle · Post by **TT350chevelle** » Mon Mar 20, 2006 10:37 am

That is not much variation, did you condition your map signal?(restrictor and fuel filter) I don't even think you need to, just set your VE table to "box in" the variation.This is a screen shot of my twinturbo V8, notice the idle VE is the same for 40 kpa and 54 kpa, works very well and virtually eliminates the unstable idle.

Brad J.

keithmac · Post by **keithmac** » Mon Mar 20, 2006 11:21 am

Yeh I did fit an inline fuel filter and restrictor (it was much worse before!), I`ve already boxed it in but may have another look into my VE table and see what`s what.

I was thinking of locking the VE while in idle mode which would free up the whole VE table, as I`ve used a few bins just to nail the idle mixture but that may be more trouble than it`s worth and cause problems elsewhere.

fscott · Post by **fscott** » Mon Mar 20, 2006 2:16 pm

keithmac wrote:Yeh I did fit an inline fuel filter and restrictor (it was much worse before!)

Stuff some cotton in between the restrictor and the filter. Worked for me!

Fred

keithmac · Post by **keithmac** » Mon Mar 20, 2006 3:28 pm

Cheers, I`ve read that before on here, might give it a go.