Knock help

[mwreed]

I did a 2nd pull this morning and I didn't like my results. Too much knock. Anyway... my mods are in my profile. I think I am running 15psi, but, I couldn't glance over at my gauge to make sure (catching up with cars). I've just turned the boost down last night. It was spiking too high before. I have my fuel pressure at 43 psi. (Trying to compensate for the small injectors.

Timing O2 TPS RPM Knck INJP

24.00º 0.35V 40.78% 3031.25rpm 0 8.19ms
23.00º 0.76V 41.18% 3093.75rpm 0 9.73ms
23.00º 0.66V 56.08% 3250.00rpm 0 11.52ms
20.00º 0.88V 73.33% 3343.75rpm 0 12.80ms
20.00º 0.88V 98.04% 3500.00rpm 0 14.34ms
18.00º 0.88V 100.00% 3625.00rpm 0 16.64ms
17.00º 0.88V 100.00% 3812.50rpm 0 19.20ms
18.00º 0.88V 100.00% 3968.75rpm 20 21.25ms
11.00º 0.88V 100.00% 4156.25rpm 27 21.50ms
6.00º 0.88V 100.00% 4375.00rpm 34 21.50ms
7.00º 0.88V 100.00% 4468.75rpm 34 21.25ms
7.00º 0.88V 100.00% 4656.25rpm 34 21.50ms
7.00º 0.88V 100.00% 4875.00rpm 33 21.50ms
7.00º 0.88V 100.00% 5000.00rpm 33 21.76ms
6.00º 0.88V 100.00% 4906.25rpm 33 21.25ms
6.00º 0.88V 100.00% 5125.00rpm 33 21.50ms
6.00º 0.88V 100.00% 5281.25rpm 32 21.25ms
9.00º 0.88V 100.00% 5187.50rpm 32 20.99ms
8.00º 0.88V 100.00% 5375.00rpm 32 21.25ms
10.00º 0.88V 100.00% 5593.75rpm 32 20.99ms
10.00º 0.88V 100.00% 5593.75rpm 32 20.22ms
10.00º 0.88V 100.00% 5687.50rpm 31 19.46ms
10.00º 0.88V 100.00% 5781.25rpm 31 19.71ms
11.00º 0.88V 100.00% 5968.75rpm 31 18.69ms
11.00º 0.88V 100.00% 6062.50rpm 31 19.46ms
10.00º 0.88V 100.00% 6000.00rpm 31 18.18ms
11.00º 0.88V 100.00% 6250.00rpm 30 17.92ms
10.00º 0.88V 100.00% 6250.00rpm 30 18.18ms
9.00º 0.88V 99.22% 6406.25rpm 31 17.41ms
9.00º 0.88V 99.22% 6343.75rpm 31 17.41ms
8.00º 0.88V 99.22% 6562.50rpm 30 17.15ms
8.00º 0.88V 99.22% 6656.25rpm 30 16.90ms
7.00º 0.88V 99.22% 6687.50rpm 30 16.90ms
7.00º 0.88V 98.82% 6750.00rpm 30 16.38ms
6.00º 0.88V 97.65% 6781.25rpm 30 16.13ms
6.00º 0.88V 70.98% 6937.50rpm 30 11.52ms
7.00º 0.84V 10.59% 6625.00rpm 26 1.79ms
37.00º 0.90V 10.59% 6406.25rpm 9 1.28ms
43.00º 0.74V 10.59% 5937.50rpm 0 1.28ms
45.00º 0.72V 10.59% 5562.50rpm 0 1.28ms

My O2 looks ok, right? I know we can't necessarily trust it, but, it looks good. Any ideas on my log? Let me know if you want more info.

Thanks,
Mike

 

[G9S1X]

that looks horrible get urself an s-afc2 and some bigger injectors. and also did u remove any honeycombs from ur maf?

 

[CanadianTSi]

You're too lean, turn down the boost some more.

 

[mwreed]

You're too lean, turn down the boost some more.

Why do you say I'm lean? I thought O2 at .88 was good for a '90. Am I missing something else? I'm also boosting about 15psi... I though you could usually boost a bit more on stock injectors. I'm running a walbro 255 with an AFPR set at 43. Are you looking at the INJP? I'm not quite sure how to read it yet. I plan on new injectors and a computer eventually, but, I can't right now. I haven't modified the MAP honeycombs either. I'll try and turn it down a bit more and see what happens.

Thanks,
Mike

 

[turbolarry]

That's a lot of knock. Stock inj.+ the high knock+ the pulled timing = your too lean. I've never ran or needed an AFPR so I can't give advise on that. The .88v off the O2 sensor is a ballpark/piece of the puzzle. For 1g's try 89v.-91v. on 91 oct. (scroll to the bottom);

http://www.roadraceengineering.com/instructions/autotimer.htm

 

[5150DSM]

You are obviously leaning out under boost which seems to be causing knock...
Solution(in your case anyways), turn down the boost. You need to be sure what your boost level is, you could be creeping up 2-3psi or more, which would account for your readings. Get on an open road, freeway, whatever and do a pull, watch the boost gauge. Are you sticking the set point and staying there?
Aloha

 

[mwreed]

You hit the nail on the head. Last night on the way home, I was able to see the it still spiked to about 20 psi. I had turned the boost down and a the fuel pressure to 40 psi, so apparently, it that's what happened. I very, very rarely ever go to WOT, so, that's why I don't usually see that kind of boost. I noticed that the knock was about 1/2 as before. I am going to be adjusting it today to stabelize the boost. It does appear that'll get it fixed. Thanks for the help and I will post when I get it set to verify it's working.

Mike

 

[mwreed]

Did another run this morning... I routed the wastegate straight from the elbow. Getting about 12psi, creeping to 15psi. Not sure I trust my gauge though. It sits off of zero when the car is off. I had another one, same model and it did the same thing shortly after I got it. Weird... I'm definately thinking of changing brand. (using autometer) I'm also running about 94 octane today. Another 2nd gear run. Something that concerns me though, is the O2. It looks like the sensore may be failing? This just started the other day... it was only going up to about .58 volts. I know dead ones are supposed to stick, but, is it possible it's dying?

Mike

TIMA.....O2......TPS......RPM......Knock...INJP
45.00º 0.64V 10.98% 4531.25rpm 0 1.28ms
44.00º 0.58V 10.98% 4312.50rpm 0 1.54ms
42.00º 0.58V 39.61% 4218.75rpm 0 8.45ms
27.00º 0.12V 81.18% 4000.00rpm 0 10.75ms
24.00º 0.68V 100.00% 3406.25rpm 0 11.78ms
20.00º 0.70V 100.00% 3250.00rpm 0 12.54ms
20.00º 0.70V 100.00% 3343.75rpm 0 13.82ms
19.00º 0.70V 100.00% 3500.00rpm 0 14.34ms
19.00º 0.70V 100.00% 3593.75rpm 0 14.34ms
19.00º 0.70V 100.00% 3718.75rpm 0 14.85ms
19.00º 0.70V 100.00% 4000.00rpm 0 15.36ms
19.00º 0.70V 100.00% 4125.00rpm 0 15.36ms
19.00º 0.70V 100.00% 4125.00rpm 0 15.62ms
20.00º 0.70V 100.00% 4343.75rpm 0 16.13ms
19.00º 0.70V 100.00% 4500.00rpm 0 16.64ms
19.00º 0.70V 100.00% 4531.25rpm 0 16.64ms
19.00º 0.70V 100.00% 4781.25rpm 0 16.90ms
19.00º 0.70V 100.00% 4781.25rpm 0 16.90ms
18.00º 0.70V 100.00% 5062.50rpm 0 16.90ms
18.00º 0.70V 100.00% 5000.00rpm 0 17.15ms
19.00º 0.70V 100.00% 5031.25rpm 0 17.41ms
19.00º 0.70V 100.00% 5250.00rpm 0 17.66ms
20.00º 0.70V 100.00% 5375.00rpm 0 17.92ms
19.00º 0.70V 100.00% 5562.50rpm 2 18.18ms
20.00º 0.70V 100.00% 5687.50rpm 2 17.92ms
20.00º 0.70V 100.00% 5781.25rpm 2 18.18ms
20.00º 0.70V 100.00% 5843.75rpm 2 18.69ms
21.00º 0.70V 100.00% 5906.25rpm 1 18.43ms
21.00º 0.70V 100.00% 6000.00rpm 1 18.69ms
21.00º 0.70V 100.00% 6125.00rpm 1 18.18ms
21.00º 0.70V 100.00% 6218.75rpm 1 17.92ms
20.00º 0.70V 100.00% 6156.25rpm 1 17.92ms
19.00º 0.70V 100.00% 6312.50rpm 0 17.41ms
20.00º 0.68V 100.00% 6562.50rpm 0 17.41ms
18.00º 0.68V 100.00% 6687.50rpm 0 17.15ms
19.00º 0.68V 100.00% 6750.00rpm 0 16.64ms
17.00º 0.68V 100.00% 6656.25rpm 0 16.38ms
17.00º 0.68V 100.00% 6750.00rpm 0 16.13ms
18.00º 0.66V 100.00% 6937.50rpm 0 16.13ms
18.00º 0.66V 100.00% 7125.00rpm 0 16.38ms
18.00º 0.66V 100.00% 7031.25rpm 0 15.62ms
17.00º 0.66V 99.61% 7156.25rpm 1 15.62ms
17.00º 0.66V 21.18% 6937.50rpm 1 1.28ms
45.00º 0.64V 10.98% 6937.50rpm 0 1.28ms

I really need injectors. Maybe Santa will be nice this year. , right.

 

[XtReMeToYz]

Im surprised it doesnt feel peppier now. No knock, better timing advance. I believe your supposed to watch o2's at idle. If they cycle than its ok, but if they dont cycle (bounce around) than they are shot. Someone else correct me if im wrong?

 

[5150DSM]

That log looks a lot better. I wouldn't be surprised if that 02 sensor is dead... Grab another one from the local parts store for like $100.00 and be done with it.

 

[Violater101]

Im surprised it doesnt feel peppier now. No knock, better timing advance. I believe your supposed to watch o2's at idle. If they cycle than its ok, but if they dont cycle (bounce around) than they are shot. Someone else correct me if im wrong?

More Boost and less timing should and most likely will make more power than lower boost and more timing IMO. Since he was spiking to 20psi, I'm sure that felt alot stronger than his 12psi spiking to 15.

 

[mwreed]

I'll have to let you know... It was this morning coming to work... Lucky if I can get up to 45 on the freeway durring rush hour. Probably won't really be able to tell 'til later this week when I have a chance to drive with less traffic.

Mike

 

[XtReMeToYz]

More Boost and less timing should and most likely will make more power than lower boost and more timing IMO. Since he was spiking to 20psi, I'm sure that felt alot stronger than his 12psi spiking to 15.

I was just basing that off my past experiences with my 14b without fuel mods. It would creep to like 18 pounds and it felt like ass compared to 14 pounds with good timing.