Xfi help needed

Blacky

Drive it like you stole it
Trying to figure out why my car will not run past 10 lb of boost. It starts breaking up. I've made two passes and one was excellent and the other one all of a sudden started breaking up. I'm looking at this XFI stuff and reading it and I cannot see anything there which would cause my issue. Any help would be appreciated. If you need any other questions asked about my car, please give me a shout. No changes were made between the 3rd and 4th run by the way Thanks in advance, Steve C
 

Attachments

  • 16507248218193696469062426542509.jpg
    16507248218193696469062426542509.jpg
    2.7 MB · Views: 67

Blacky

Drive it like you stole it
Yes so far I have put new plugs in put new plug wires in changed the coil pack. Checked all the connections. Visually checked for vacuum leaks. Going under car to make sure. My external boost controller is working and also going to check by the starter to make sure the starter wires aren't hitting anything. I think I've had that before and read about it. Looking to go to BG but I can't do it with only 10 lb and probably not even that 8. Thanks, Chuck
 

Blacky

Drive it like you stole it
I do not log fuel pressure but I have a fuel pressure gauge. To be honest with you. I didn't check it when this run was in progress. I have been watching it now and when I get to about 10 lb of boost. I have over 50 lb of pressure which is about correct. Being that breaks up at 10:00, I can't check it for hire boost at this time. Thanks for looking
 
if you have static of 43.5 fuel pressure no add 10 pounds to that you should see 53.5 I was thinking that you might have to much fuel pressure so just for the hell of it recheck static fuel pressure
 

Mr.Spool

Well-Known Member
Trying to figure out why my car will not run past 10 lb of boost. It starts breaking up. I've made two passes and one was excellent and the other one all of a sudden started breaking up. I'm looking at this XFI stuff and reading it and I cannot see anything there which would cause my issue. Any help would be appreciated. If you need any other questions asked about my car, please give me a shout. No changes were made between the 3rd and 4th run by the way Thanks in advance, Steve C
Spring setting?
Which controller?
Electronic or manual?
 

Blacky

Drive it like you stole it
The fuel that is set at 42 lb. The spring and the precision wastegate is set at 9.4 and I have a gspeed manual boost controller . I hope I got all that information right. Thank you
 

Reggie West

Well-Known Member
TurboBuick.Com Supporter!
Sounds like you are exactly at the boost level you should be. Leave it there and make sure your AF table is good before you turn it up. Go up in 2 psi increments at a time and check your data logs. Small steps.
 

Mr.Spool

Well-Known Member
The fuel that is set at 42 lb. The spring and the precision wastegate is set at 9.4 and I have a gspeed manual boost controller . I hope I got all that information right. Thank you
It pushed the gate open at 10lb because that is what spring you have on the gate.
No you need manifold pressure from your controller or co2 to further keep pressure on the gate for more boost.
Or a heavier spring in the wastegate
 

Chuck Leeper

8/10's of a century!
Staff member
The wg opening doesn't cause the engine to "break up".
"The spring and the precision wastegate is set at 9.4 and I have a gspeed manual boost controller ".
The 2 screen shots show near identical scans, and the boost shows right at 16+/-.
Where are you seeing 10#?
No response to post #2. I assume the answer is no plug check?
 

Blacky

Drive it like you stole it
Yes I've been running the same setup for a couple years and the boost will go up to 16 and that gets me all the speed I need. But right now I can't get the boost to go above 10 because it's breaking up just like it did at the track the last time I was there as shown in the picture. I appreciate all the help that I have been receiving and we have been troubleshooting but so far nothing. I think we had all the spark stuff covered and now I'm just clueless but it sure does pull good up till about 10 lb. By that I mean I put on another coil pack. I changed the crank sensor. Has new spark plugs and wires.
 

Blacky

Drive it like you stole it
The balancer bolt to the engine? I have not checked that if that's what you're referring to but anything different would help maybe figure this puzzle out
 

broke

broke
Yes the crank balancer bolt. If it becomes loose the reluctor ring can move forward enough to lose the crank signal.
 
Top