can someone give me link or explain what i need to do to tune the maf for boost. i want to go 2bar sd but i can't at the moment. i know with the 2bar set up you have boost enrichment, so that when you start to roll into boost (even at part throttle) it will start to add fuel. how can you do that with the maf setup? i know with my heavy tahoe its bound to go into a small amount of boost at part throtle. and even on a small load i don't think 14.7 is ok for boost.

 

Adjust your PE enable MAP constant to come on at 95 kpa and your HOT and COLD PE Enable vs %TPS vs RPM tables to 40 for all rpm. Set your PE delay constant to 0 and your PE Mode delay Bypass RPM to 0.

Adjust your 100 and 105 kpa rows in your Main VE vs RPM vs MAP table up about 5-6% from 2000 rpm and above and leave the MAF table alone. You want it to dip down to 4% and 2 % at 4000 and 4400 rpm and maybe raise it from 8% to 15% from 5200 rpm and above.

Verify your results with a WBO2 gauge if you have one.

Set your PE Fuel EQ. Ratio vs RPM to 11.5 or so (1.28) and monitor for KR depending on your boost level. Maybe set it to under 11 if you are running over 6 PSI boost.

Hope I didn't leave anything out. Log for sure and go slow to start till you are sure your tune is good. You may not need to go SD or 2BarOS. I still run the MAF at 12 psi and methanol to boost the fuel.

 

THANK YOU, i've been searching for that answer everywhere. with all the stickies we have you would think there would be something about maf and boost. i'm planing on installing the turbo after the first of march. going to go get a baseline run first.

i do have a wideband and boost, egt,and fuel pressure gauges.

 

not sure if you were talking about the maf, ve, or boost.

 

Those comments you highlighted are all for the last two rows of the Main VE table for 100 kpa and 105 kpa. The two rows should be identical. The MAF takes over at 4000 rpm, when you are not in PE and for some reason you need to drop the % you increase the rows in the VE down a bit in that area to compensate for it. The higher rpm areas are increased by a greater % to be safe over 5200 rpm but level off at 15% increase by 6000 rpm. The only problem I find is that it sometimes drops the AFR into the low 10's or high 9's after the shift to 3rd gear. At least it is going richer not leaner. It must be something to do with the increased load and torque generated in 3rd gear.

 

Try to set your spark tables to around 16-17 deg wot

 

is that a nice low start?

 

how does this look for starters?

 

I would try to set your WOT timing at 10 to 12 degrees to start and work your way up slowly from there once you have everything working properly. I have mine set at 17 but I get some KR from time to time and I am running meth and a 10.5 afr once the meth cuts in.

My Spark Advance high and low octane tables max at 10* from 1200 rpm and .68 gm/cyl to 5200 rpm and .84 gm /cyl down to 1.2 gm/cyl.
5600 rpm and .84 gm/cyl = 9* to 1.2 gm/cyl
6000 to 7200 rpm and .84 gm/cyl = 5* to 1.2 gm/cyl

I am adding timing through PE and the AFR Spark Advance Correction Vs AFR (PE) Vs RPM to get 17* at WOT.