Hey guys,

My BLM RPM & MAP Boundaries are set at the following:

900-1200-2000

30-50-80

I have taken several logs at idle and my MAP is 65-70. ( My cam has a ton of duration, lift is .580 .571)

Should I set low map to 65?

Also, im not sure what to do with the mid and high map. I took logs at cruise and my MAP value seems to decrease in my normal driving range 1800-2500, map is 45-55 in those ranges. When im wide open at the 1800-2500 rpm range however MAP does jump to 85 or so. Should I leave the mid and high boundaries be and just move the low MAP boundary?

Thanks

 

https://www.camaroz28.com/forums/sho...&highlight=BLM

I think this thread will answer all your questions.

Ben

 

I've adjusted my blm map. App... 97ss 383-D1 MM6 72#_inj.~ 14->15psi.
Cam... 231/ 240 w/ .538 .560 lift 114lsa.
BLM changed to...
1500/ 2000/ 2750 rpm
40/60/80 kpa
I also lock blm @ 128 with WOT trigger ON. Also dropped my MAF cal by 3%.
PE vs Temp zero & knock retard zero. PE vs rpm only. Could not ge PE vs Temp to work very good.
My manifold idle is around 50 to 60 kpa, & 14.7 afr.
This change worked for me. I use a DynoJet WB that really helped w/ on the road tune. Hope this helps. B.

 

Are you running an M6 or A4 (I guess M6 from your values)? If A4, what's your stall? What's your rear end gearing, and cruising speeds? The idea with BLM boundaries is to define a different cell for each of the most frequently used "modes" of driving you're doing, idle, low/mid/high RPM cruising, low/mid/high PE, etc. You want to set your RPM zones and MAP zones to split those up as efficiently as possible.

Given your brief readings, and the fact that you have a cam (so probably enjoy spirited driving), I'd try at first adjusting your MAP boundaries to 43/62/80 (maybe 40/60/80-45/65/80 depending on the accuracy of your estimate) and RPM to 1200/1800/2300. Datalogging will help you see if you're using them efficiently or not. RPM is the easiet to adjust, because you directly control what your RPMs are and what zones you typically run in; MAP however is dependent on other factors so takes a bit more effort to dial in.

 

Hey guys,

Yea my combo is
396 LT1
AFR 210 (55 cc) heads
Cam (already listed)
M6
rear end 4.10

Dyno 477 rwhp, 432 rwtq

I tried RPM, 1500, 2000, 2500
MAP, 40, 60, 70

Thus far the car seems like its a thousand times more drivable than the stock settings. Can actually drive the car a little bit under 2 grand. One question I do have, will this affect the WOT parameters? I guess Im questioning whether or not I would need a blm locker?

 

I would to ensure proper WOT fueling. This has nothing to do with your boundaries.