Lost power with MAT sensor

[Holden202T]

I agree with jayme, try dropping off the timing where the power drops off and see if that helps .... the best way to tune spark is by most torque produced so you should be able to go off before and after graphs to see whats better ?

also with the fuelling it seems to be a personal preference how rich.lean to tune on boost.

I personally tend to stay on the safe side and go for something like 11.5 or a bit leaner for about 15-20 pis boost .... but I've heard of people running 11.9 on over 20psi boost and they seem to think its ok!

like I said, for me, im happy with safe rich

[VL400]

does it still run a boost solinoid its not limiting boost v's intake temp with the higher reading iat

Yeah thats pretty much the only thing i could find that uses the IAT.

[immortality]

does it still run a boost solinoid its not limiting boost v's intake temp with the higher reading iat

I think it is, this could well be the issue.

We didn't have a MAP sensor hooked up this time around to see what happening boost wise

edit: just checked the data, airflow drops when the IAT goes above 66° C so I think Delco has nailed it

XU6 MAT sensor air flow 2.png

[Jayme]

yeah on the l67 I tuned, we disconnected the boost solenoid and reran the pipes so it only opens the bypass plate off throttle... that might just sort it without having to move or retune anything.

[immortality]

I've adjusted the Supercharger - Boost Limit Vs Intake Air Temp table to compensate for the higher IAT's seen with the MAT sensor. That should solve the problem.

Now we can finish fine tuning the AFR's and play with the timing.

I'm with Holden202T, probably go just a bit richer to keep it safe.

edit: I think I need to figure out how to use the datalogger pass-thru option, that way I can log my own boost pressure with a MAP sensor rather than relying on the data from the dyno facility. Then I need to see If I can piggyback off his WB O2 somehow.

I think I need to have a chat with the operator.

[krusty]

You may be able to log dyno MAP VS roadspeed to interpolate back to TP logs. Always piss off the boost reduction solenoid asap once you touch a super6. It's a friday arvo engineering job lol

[immortality]

We were using RPM to compare data. The dyno uses injector pulses to calculate RPM.

[antus]

Yep, last L67 I touched the boost solenoid caused problems. Had to remove that.

[ejukated]

they tend to leak when they get dirty causing loss of precious boost!

[immortality]

I will suggest it to the owner. Is there a guide anywhere to follow?