Modshack...BAMM experiments...
05-10-2004, 09:37 AM
#1
AudiWorld Uber User
Thread Starter
Modshack...BAMM experiments...
That would be the Big *** Maf Mod. Just did some pre-post vag runs on this and the results look promising. What I did was source a piece of thin-walled stainless, 3" 0D so as not to mess with the Samco/TTDA ID limitations. Due to it's thinwall, the surface area inside the MAF is now 10% bigger diameter than the stock plastic piece. As you would expect, velocity (Hence G/Sec readings) will be reduced but you'll get MORE air overall. This morning's run with the stock MAF yeilded 200 g/sec (Using the VW A MAF), 180 after for about a 10% reduction. As the car runs a little fat (rich) under boost I was hoping this would bring things into a little better ratio from An Air-fuel perspective. First, here's the new MAF housing installed...Spiffy eh?:
<img src="http://images6.fotki.com/v74/photos/7/7305/750827/DSC02379-vi.jpg">
Here's the part under construction. Hacksaw and a die grinder is all you need:
<img src="http://images5.fotki.com/v62/photos/7/7305/750827/IMG_6829-vi.jpg">
I just used a MAF holder from a cut up "A" housing and JB welded it to the tube. I also fabbed up some quick release Knurled hold-downs too for easy MAF changes.
Here's the A/F results. SOme caveats though, the post BAMM curve is with no adaptation time, so I would expect that to change and smooth a bit as adaptation tables are built up. This is also before the 4 bar FPR. Corky Bell states 12.5 to 13 is the optimum A/F ratio under boost. The car now seems to spend more time in this range which would be better for power delivery. Too rich and you lose power. I think the car was a bit rich Pre-BAMM..
<img src="http://images6.fotki.com/v74/photos/7/7305/750827/allmods_afcopy-vi.jpg">
Anyway, I'll do some follow up VAG runs to make sure all's well, but right now things appear to be pretty much in line. The difference in power delivery is noticeable.. You can tell there's more there in the most used RPM ranges. More as I experiment...
Also of interest may be the latest pressure readings with all mods (EH manifold and BAMM). The boost machine was set at a relatively conservative setting. As would be expected, the logged Manifold pressures are lower than Pre-BAMM because this is a calculated number from the MAF reading and don't reflect actual (gauge reported) Manifold pressures....
<img src="http://images6.fotki.com/v75/photos/7/7305/776545/allmodscopy-vi.jpg">
Steve
<img src="http://images6.fotki.com/v74/photos/7/7305/750827/DSC02379-vi.jpg">
Here's the part under construction. Hacksaw and a die grinder is all you need:
<img src="http://images5.fotki.com/v62/photos/7/7305/750827/IMG_6829-vi.jpg">
I just used a MAF holder from a cut up "A" housing and JB welded it to the tube. I also fabbed up some quick release Knurled hold-downs too for easy MAF changes.
Here's the A/F results. SOme caveats though, the post BAMM curve is with no adaptation time, so I would expect that to change and smooth a bit as adaptation tables are built up. This is also before the 4 bar FPR. Corky Bell states 12.5 to 13 is the optimum A/F ratio under boost. The car now seems to spend more time in this range which would be better for power delivery. Too rich and you lose power. I think the car was a bit rich Pre-BAMM..
<img src="http://images6.fotki.com/v74/photos/7/7305/750827/allmods_afcopy-vi.jpg">
Anyway, I'll do some follow up VAG runs to make sure all's well, but right now things appear to be pretty much in line. The difference in power delivery is noticeable.. You can tell there's more there in the most used RPM ranges. More as I experiment...
Also of interest may be the latest pressure readings with all mods (EH manifold and BAMM). The boost machine was set at a relatively conservative setting. As would be expected, the logged Manifold pressures are lower than Pre-BAMM because this is a calculated number from the MAF reading and don't reflect actual (gauge reported) Manifold pressures....
<img src="http://images6.fotki.com/v75/photos/7/7305/776545/allmodscopy-vi.jpg">
Steve
