bad stumble just off idle to @4000. need map check. pic inside. ghetto kit

[quicky]

since I got this thing running again it's been stumbling only right off idle to @3500 to 4000. off boost only. really bad when cold. not nearly as bad once warm. idles great and on boost is fine. pulls really hard on boost till redline no misfire. plugs at .018 and look good.
I currently have the 6lbs spring in it. it's a motorhead ghetto kit. I don't remember any stumble last time it was running. (@5 years ago)
can someone take a look at the map and see if it looks ok. it's the map that dennis (tmh) sent with the kit. it made 259.9 rwhp on the dyno @ 7 years ago. I freshend up the motor with new rings, new cylinder from ape. machine shop did a valve job and surfaced the head. new guides motor doesn't smoke at all.
................0 2 5 10 20 40 60 80 100

500..... 0 0 0 0 0 0 0 0 0
750..... 0 0 0 0 0 0 0 0 0
1000..... 0 0 0 0 0 0 0 0 0
1250..... 2 0 -15 -10 0 0 0 0 0
1500..... 5 10 -15 -10 0 4 0 0 0
1750..... 5 10 -15 -10 0 4 3 3 3
2000..... 5 10 -15 -10 0 4 4 4 4
2250..... 5 10 -15 -10 0 4 4 4 4
2500..... 5 10 -15 -10 0 4 4 4 4
2750..... 5 10 -15 -10 0 4 4 4 4
3000..... 0 10 -15 -10 0 4 4 4 4
3250..... 0 0 -20 -10 0 4 4 4 4
3500..... 0 0 -20 -10 0 4 4 4 4
3750..... 0 0 -20 -3 0 0 4 4 4
4000..... 0 0 -20 -3 0 0 4 4 4
4250..... 0 0 0 -3 0 0 4 4 4
4500..... 0 0 0 -3 0 0 4 4 4
4750..... 0 0 0 0 5 4 5 7 7
5000..... 0 0 0 0 10 7 7 10 10
5250..... 0 0 -10 -5 11 8 8 11 10
5500..... 0 -7 0 0 13 10 9 12 11
5750..... 0 0 0 5 15 10 10 15 14
6000..... 0 0 0 8 17 11 11 16 20
6250..... 0 0 3 10 19 12 11 14 21
6500..... 0 0 6 14 22 13 11 13 20
6750.....0 0 7 15 22 13 11 14 21
7000..... 0 0 9 15 22 12 11 16 23
7250.....0 0 7 15 24 13 14 18 25
7500........ 0 0 6 17 26 13 16 22 29
7750..... . 0 0 7 15 23 13 18 25 31
8000..... 0 0 7 13 20 12 20 28 29
8250..... 0 0 12 18 23 12 20 27 27
8500..... 0 0 16 22 26 12 20 27 28
8750..... 0 0 14 21 26 12 18 24 24
9000..... 0 0 13 20 26 13 17 23 22
9250..... 0 0 14 22 27 13 19 26 29
9500..... 0 0 15 24 28 13 20 40 33
9750..... 0 0 15 24 29 18 21 43 34
10000..... 0 0 15 25 30 20 23 45 35
10250..... 0 0 18 27 32 20 24 48 37
10500..... 0 0 20 30 35 20 26 50 40
10750..... 0 0 22 23 30 18 24 46 40
11000..... 0 0 0 19 25 11 22 43 50

 

[OZBooster]

3250-4000 at 5% look wrong , there should not be that much change without graduation in any direction

you probably have the old type shim in the FMU i would start there , strip it check it or just upgrade
Then, reset the fuel pressure to 43, and adjust the brass bleed valve in 1/8 turn increments untill the transition to boost is smooth , if you have to go more than 1/2 turn either way something else it up and return it to the original position untill you find out what
when you have transition smooth its dyno time

 

[quicky]

it is definitely rich. but why? the fmu never gave me any problems before but since you mentioned it oz i'm thinking your right. it is old. I bought the kit from dennis @ 6 months after he came out with the ghetto kits so it's probably the old style. I'm posting 2 vids. 1 is when the motor is warm and the other is when it's hot. been idling for @ 15 mins. in the vids i'm holding the throttle steady and it's stumbling and then on it's own it finally clears up and revs increase on it's own. in the hot vid it's popping flames out the dump. definitely rich. gonna pull the fmu apart today. what am I looking for? and where do I get parts?
thanks oz

 

[quicky]

got the fmu apart. pretty easy. was very clean inside. don't see anything wrong. nothing broke or leaking gaskets. what could be the problem? take a look.

 

[OZBooster]

Ok your looking for creases or wear on the shim, thats your sealing surface and any irregularity puts it out
if memory serves first upgrade on them was a .005 shim , some even went to .010
but new ones are very different design and much more reliable

 

[quicky]

ok, I didn't see anything wrong with the shim. I cleaned everything with brake cleaner and reassembled the fmu. this time I put the shim in upside down. it started right up and I noticed the fuel pressure gauge is rock steady now. before the needle was jumping over a 5lb spread very quickly. like from say 40-45 lbs but now it's rock steady at 43 lbs. going to ride it to work tomorrow and see how it does. going to order some .010 stainless steel to make a shim with. can't find any local. tried today.
thanks oz !

 

[arthur39]

Contact BEGI, Great company to deal with, you can buy a shim here or even have it overhauled, I personally have done the new valve design, They will even set up the rising rate and fuel pressure to your specs FMU Parts and Rebuild Kits - BEGi

 

[quicky]

drove it today to work. wow.... fuel pressure went to @80 lbs at idle and stayed there most of the day. on the way home it dropped to @ 35 at idle and then to @ 20 and killed the motor. barely made it home. ordered the rebuild kit from begi this morning. should get it quick. they are only @ 2 1/2 hours away from me.