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diddles

Active Member
Dec 17, 2009
289
0
Hi, my car feels underpower and feels like its dumping boost intermitantly, ive done some logs, could someone please advise what could be wrong. The air mass only reads upto a max of 143g/s. I've done two logs in 3rd gear and merged them into one.



 
Your peak air flow is at 5000 - 5100 revs then it looks like you are letting off the throttle. Can you do a run to redline?

Also for a fuller picture can you log fuelling (031) timing correction (020), boost + N75 (118) and EGT (112).

I normally do

002 and 031 to show fuelling and what injector cycle it's taking to hit the requests

003 and 020 to show air flow with timing and corrections

118 and 112 to show boost + intake temps with EGT and any fuel dumping.

There are probably better combinations than this but thats what I usually go for.
 
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Thanks for the reply, it was foot down to 5,600rpm. On the air mass logs you can see the load is 100% at 5,600 rpm and reads very low. It should be higher through out the rev range I would have thought. Maybe leaky dv or knackered maf?
I did an earlier run to redline in second and only reached a peak g/s of 165.

Am I able to log the blocks you recommend in 2nd gear or does it have to be 3rd?
 
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I've checked my dv and that seems fine, what g/s peak should I be seeing on a standard lcr 225?
 
I unplugged the maf and there wasn't a great difference felt a littl bit better if anything but can't be sure. Does my boost graph look ok, looks abit wavey if you know what I mean.
 
Could a dodgy n75 valve cause the boost to fluctuate like shown in the graph?
 
Could a dodgy n75 valve cause the boost to fluctuate like shown in the graph?

Wouldn't say the fluctuations were too much to worry about. Log your N75 duty cycle on block 118 and see what it's doing. I replaced mine a few weeks back as I suspected it being faulty and at first it felt like the new one was much more responsive - boost spikes were reigned in by about 2 psi according to my gauge so was happy with that. The N75 has supposedly been revised over the years as the end character in the part number has changed - I think the latest ones are 'E' so it's worth 30 quid or so and trying a new one if you suspect there's something up with it.
 
Nice one mate, will run some more logs with the blocks you mentioned. Still learning logging petrols as I am used to logging my old gttdi. Thanks!
 
I just done a run to redline in 3rd gear with a Honda s2000 cone fitted and the max g/s I got was 177 so all it good as thats roughly 223bhp?
 
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