2000 turbo xj tuning

[Xjboss]

just got finished turboing my xj and im now onto the real challenge....... tuning
im running aem fic 1913 and i have it all wired up and ready to go but thought id see if anyone with some experience with this program could share some of the tips and tricks to getting it set up and working properly.

the set up is a t3/t4 55 trim choo choo boi, fed with 36lb injectors.

thanks in advance

 

[Cummins90]

I'm running a 53mm 60trim on a stock 4.0. Do you have a federal 2000 without the mini cats? I can send you some screen shots of my set up and maps. I intentionally hold closed loop for the first 4-5 psi.

 

[Xjboss]

Not sure what you mean by federal 2000 but it's a canadian vehicle and it just has one cat.
If you would send me some screen shots that would be incredibly helpful in getting this thing dialed in.
Just out of curiosity, what's the benefit of running closed loop for the first few psi?

Appreciate the help

 

[Cummins90]

The computers on the dual cat motors takes a different approach to tune. But I haven't experienced a non cali emissions 2000 like you have yet so I'm curious.

Did you install the FIC harness yet? I ask because I have extension harnesses that spare your factory harness and are transferable vehicle to vehicle.

I'll PM you for the screen shots. We cant place pics directly into this forum without a 3d party host right?

 

[Cummins90]

I keep closed loop for 4-5psig because I found my ecu targets 12.5 AFR when open loop is triggered. I would often achieve part throttle boost while highway cruising and I would be overly rich when not needed. I have a 5 speed so there was many times I would hit 14.7 PSIA and didnt need the enrichment. I allowed my MAP clamp to be above resting voltage at 4.9v. Then I decreased a percentage of the signal to force it back to closed loop. The higher the RPM the more I would allow open loop at a lower manifold pressure. This increased my drivability and brought my fuel economy almost back to stock. Higher boost runs still had enrichment to 11.5AFR my MPG is down slightly but my smiles-per-mile have gone way up.

It is important to note that I retarded timing from the start of manifold pressure above 14.7psia.

 

[cherokeecrawler]

I plan on turboing mine soon, but what do yall think would be required just to run around 4-6 pounds of boost? Other than a very basic understanding of how the turbo mechanics work, I don't know much about tuning or what turbo parts i would need... thanks in advance.

 

[Xjboss]

I keep closed loop for 4-5psig because I found my ecu targets 12.5 AFR when open loop is triggered. I would often achieve part throttle boost while highway cruising and I would be overly rich when not needed. I have a 5 speed so there was many times I would hit 14.7 PSIA and didnt need the enrichment. I allowed my MAP clamp to be above resting voltage at 4.9v. Then I decreased a percentage of the signal to force it back to closed loop. The higher the RPM the more I would allow open loop at a lower manifold pressure. This increased my drivability and brought my fuel economy almost back to stock. Higher boost runs still had enrichment to 11.5AFR my MPG is down slightly but my smiles-per-mile have gone way up.

It is important to note that I retarded timing from the start of manifold pressure above 14.7psia.

Interesting, sounds like you've spent some time figuring out the program and its awesome your willing to share it.
I have an auto so it'll be interesting to see how that effects boost and whatnot.

 

[Cummins90]

Start by finding what triggers your open loop. Do this by watching your live data on a scan tool as you drive. When the fuel system switches to "open" that is open loop fueling. My 96 5speed XJ seems to take the last O2 reading before open loop and adjusts the open loop part of the map all the way up the load range.