To setup the stage:
I have an 03TT, 20k miles, evo610 kit which has the gt28's, and EvomsIT.

I am usually hitting 1.3bar and occassionaly in opitimal conditions 1.4bar with 91 octane.

I usually only get a chance to drive the car in the evening after work (6 or 7pm) so temperatures are low in Sacramento.

Scenario 1:
I go through the gears pulling hard 1st, 2nd, 3rd. About midway through 3rd gear the car will remain at .9bar and stop pulling hard. My foot is still to the metal but car just stops pulling hard and remains at .9 bar as the RPM's go up. I upshift to 4th and everything is great and it continues to pull.

Scenario 2: (completely separate run)
I go through the cars pulling hard 1st,2nd,3rd. Shift into fourth and car reaches 1.3 bar but it stops pulling hard, feels like it just hits a wall. RPM's continue to climb but car just stops pulling hard.

**This does not happen ALL THE TIME but often enough for me to want to figure out whats going on.**

Any ideas?

 

what tune do you have?

 

Meaning octane? Or which vendor?

91 octane and Evoms

 

Yeah vendor.. I would give them a shout and see if they have any thoughts. I bet they could tweak the tune and alleviate that problem.

Happy New Year..

 

You need to datalog your runs to see what's going on. What supporting mods do you have on your car? Also, you could try running 100 oct fuel. Your 91 oct could be junk and your ECU is pulling timing and cutting boost. You would see this in a datalog.

 

I have EVO intake, evo diverter valves, gt28's, exhaust

 

If it's not the gas, you may have a slight boost leak somewhere.

 

I've heard of situations where where the car is say supposed to be pulling 1.2 bar (on tune) and then hits 1.0 bar in 3rd gear pulling hard but still not showing peak boost of 1.2 bar per the tune?? Is this the same sort of thing here?

 

cruze down to marconi and watt the 76 station that sells 100 oct fuel if you have a race gas file set it and enjoy there is a world of difference merry christmas steve

 

If it was a boost leak wouldn't it happen all the time?
These incidents are spontaneous.

 

I had a similar issue with my B5S4 and it was a boost leak. Worth checking..

 

Plus 1

 

Check your DVs too, they could be starting to fail. It could be a number of things but start with the gas.

 

Yup. Put some race fuel in to see if it's yanking timing. 4th gear is a pretty good TQ load.

 

how would you do this? what equipment would you use and how would you set it /configure it?

There are many ways and different types of eqipment for DAQ, most of what I have seen has been on race cars, I am not sure of what is used on street cars per se.