Rocky Mountain Club B5

Discussion Forums => Modifications => Topic started by: Rusty on March 21, 2005, 01:08:33 PM

Title: Chapter Closed - Cartech and MBC removed...
Post by: Rusty on March 21, 2005, 01:08:33 PM
A Chapter Closed in my B5 Book...

...and a new one about to open.

1) I have retired the venerable Cartech FMU (rising rate adjustable fuel pressure regulator) (
2) removed my 440cc injectors and put the 380's back in,
3) upped the fuel pressure to compensate, and
4) Removed my Dawes MBC

So right now I'm running totally stock boost.  Thanks to my other mods, the car is still darn quick, but it's real thin on the top end, with max boost 6 lbs in 3rd gear, 8 lbs in 4th.

Why have I done such a thing?  Preparation for Dynojet PowerCommander III fuel management install ( - I'm going to log some baseline dyno and engine data to use in creating the new fuel maps. Then I'll put the MBC back in and increase boost a pound at a time while logging, until I go too lean.  Then I'll have some good trend data to help program the PCIII.  Then I'll install the PCIII (which I have had since late November :banghead: ). This will be fun. :D

OBTW, since I have 124K miles on my original O2 sensors, I'll be replacing them before I do this tuning effort...

OBTW2, fresh spark plugs going in this week. ;)

My biggest disappointment was not being able to come to the Dyno Day GTG with the Cartech - as posted elsewhere, bald tires, bad CA's, and no money to replace them have kept me away.  So I decided to go ahead and do what I can w/o spending money.

But damn.  I know a lot of people wanted to see how my tinkering stacked up against chipping, head-to-head.  I wanted to see it, too.  dammit...  damn tranny gone bad in wife's truck.  If it wasn't for that, I'd risk the bald tires and bad CA's to come up there.  When it rains, it pours...