Before I get the usual responses about the accuracy of dynos versus various conditions, I always dyno in close to the same weather and always at the same dyno.

Now, all of my dynos with the TVS have been around the low 300s whp mark and 260s torque. (mods in sig). The only variations have been different tunes.
Went to the dyno again last weekend and the most I could get out of it w/o KR was 276/234. I couldnt go more agressive than 18* with an 11.3 afr. I put down over 300whp a few months ago with 20* timing and an 11.7 afr. A few pulls on the street while datalogging confirmed the results of the dyno. 3-6 deg of KR through most of third gear, especially above 6k rpm.

Compression from 1 to 4 = 205, 195, 200, 195
Dipstick does NOT pop up
Runs smooth, no hesitation even when KR is present
Does not sound like WRX
No blue or white smoke from exhaust
Coolant and oil are both clean
Spark plugs are brand new NGK BKR7E gapped at .032


I have not done a leakdown since I dont have a kit. Going to try to find someone to lend me theirs so I can do a test. But the symptoms don't point to anything being chunked

Ideas?

 

same tank of gas?

 

cat could be clogging up

 

I think he'd see a boost increase if this occurred. Bad fuel is my guess also....

 

Sub'd

I have similar issue, similar KR in 3rd, but car runs absolutely fine.

 

IC Pump malfunction?
How are the IAT2s?

 

Been getting this KR for months and I've just been dropping timing and adding fuel to bandaid teh problem. So it is regardless of fuel.

Forgot to mention, IAT2 never went above 136 after repeated 3rd gear pulls on the dyno. New pump about a month ago, no air in the lines.

No boost increase. getting about 20PSI.

 

have you sea foamed the motor? maybe it is carbon building up in on the piston creating hot spots?

 

I dont like the idea of seafoam, but you're the 3rd person to tell me to try it. alot of people i know swear by it, but I dont see how it could do anything but harm the engine.

Although if the engine is possibly duffed already, theres no harm in trying

 

nothing wrong with seafoam used it on all my cars with nothing but positives

 

gave in and tried the seafoam. half in the gas tank, half through the vac line on the intake manifold that goes to the back of boost bpv.

Car smoked like a diesel rolling coal for a mile driving easy, then went w0t. that seemed to clear everything out. i was able to squeeze 1 more degree of timing out of it before the KR presented at the top of 3rd gear, 6700 rpms, same afr of 11.3

Didnt do much data logging, only 2 pulls, since it needs taken to 110mph to see if the KR in 3rd gear is gone. It's not worth going that fast on the street. Wish I could afford more dyno time

 

Do you aways fill up at the same gas station? Try a different one if so

 

almost always the same Shell station. Occasionally a Marathon. Last tank has been Marathon 93. No difference yet.

 

Was it doing it before and after the new plugs?

 

yes. swapped plugs from autolite 3922 to ngk bkr7e and the knock was exatly the same.

 

Well, it doesn't surprise me that you cant get 18* to redline on 93 octane, but it's odd that it used to be okay, with 20 and now won't take 18. You didn't dyno in 2nd before did you? j/k

 

haha no. definitely in 3rd. it made over 300whp before 6500rpms this spring. It loved the timing. None of my mods have changed.

 

Try leaning it out a little bit during peak torque... gas quality goes to **** this time of year.

Get some meth...

 

You do realize that the fuel that you're putting into the car is different this time of year. Seasonal blends FTL. I even noticed mine pinging under boost in the lower RPMs.

 

but this KR has been happening for months, when it was hotter than hell. been adding fuel and dropping timing progressively since I discovered the KR.

I just put it on the dyno 2 weeks ago to confirm my suspicions of power loss.

 

Have you zero'd out your iat adders?

 

have you ever filled up your tank while the tanker was refueling the gas station? sometimes when they have the pump in the the ground it stirs up sediment that you could be pumping into your car. if you ever see the tanker there DO NOT fill up

 

No I think the KR is from using the wrong toothpaste:



Or using the wrong fuel ...



Just kidding ...

 

Give him a break guys, he's smarter then this being a poor fuel problem.

 

Modern pumps all have filters on them designed to clog up and cut flow before you can pump any sediment into your car..