MOBE

I dynoed my car again today and pulled 338hp & 347tq. This was with 4* of KR! WTF!!! Everytime I dyno or atap my car I get 4* of KR! I'M GETTING SICK OF THIS! <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> What could possibly be causing this? Am I getting false knock? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> I've got a catch can. I've used top engine cleaner. I've tried to lean it out, and richen it up. Nothing works. The atap said like 12* of timing was being pulled. Thats quite a bit of timing/hp to be losing. I just don't know what to do. <img border="0" alt="[cry]" title="" src="graemlins/gr_cry.gif" />

<img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" /> ...leaving now to go drive it in to the lake! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

All help and opinions are much appreciated.

TIA!

<small>[ February 15, 2003, 01:09 PM: Message edited by: MOBE ]</small>

niphilli

Does your sig have your complete list of mods? If so those are very high power numbers for you to be pulling with all of that KR. What is your total timing? If it is indeed false KR I would look for your exhaust system banging somewhere, or get rid of your pulley, both of these can cause KR. Before you go through the trouble of switching pulleys burn out the tank of gas you have and replace it with some good high octane stuff, also look for exhaust system contacting something it should not. If the exhaust looks good and you have good gas go ahead and put the stock pulley back on. If you are still getting KR then it must be something internal???? Good luck.

-Nick

MOBE

Yes, thats the whole list of mods. Don't remember the total timing off hand (25 I think). I'll have to get it off my friends laptop later. I was getting 4* KR with the stock pulley also, so I don't think thats the problem. I was also getting it when I still had factory exhaust and after I put all the Hooker exhaust on. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

It did appear to be running lean on the dyno though.

niphilli

25 deg of timing is not great but it is not bad either. You are definately not getting 12 degrees of timing pulled because of your KR. If you were getting all of this KR with the stock exhaust and pulley then it sounds like something is going on internally. What did the dyno graph look like? Any pinging/detonation? what were your 02 readings, or better yet what was your A/F?

CHRISPY

Are you dynoing with wideband or LS1 edit?
How did it "appear" to be running lean?
You need a wideband and LS1edit to be able to tune any car properly.
Good Luck,
Chris

MOBE

I used wideband. A/f was 14.8. I'm getting detonation from about 4000rpm through 6000.

Dope

iTrader: (2)

So what's the problem? It's not exactly a mystery, you're getting KR because you're running wayyy lean, richen it up. I didn't see a MAFT in your list so you should probably invest in one (or LS1-edit). If you want to be cheap, using a stock MAF should help out a bunch too. Most people find they run lean with descreened MAFs.

Dope

WMSuperSport

iTrader: (23)

14.8 seems rediculous. Fatten her up.

Pro Stock John

iTrader: (34)

Surely you know that's too lean.

I would not want to be over 13:1 AF with heads and cam.

Personally, I reccomend 12.5:1 AF for heads/cam cars, and 12:1 - 12.5:1 AF for big cube cars.

Once you get on the street, your engine is under more load than it is on a Dynojet.

I bet your plug tips are pure white.

Check your Ltrims, perhaps you need bigger injectors or something.

Y2K2LS1

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> Once you get on the street, your engine is under more load than it is on a Dynojet.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thats why most of the shops around here use a Mustang, not a silly ovverated d-jet. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

MOBE

I realize thats pretty lean. I just wasn't sure if that was the whole problem. I'm not an expert yet at knowing how to read some of the readings. But, I'm learning! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

...Already looking into a MAFT. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

Thanks guys!

Pro Stock John

iTrader: (34)

Yes that's your problem. PCM is pulling timing or reported actual KR since you are underfueled at WOT. I would not go WOT again until I addressed it.

Do you have a stock ported MAF?

MOBE

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Pro Stock John:
<strong> Yes that's your problem. PCM is pulling timing or reported actual KR since you are underfueled at WOT. I would not go WOT again until I addressed it.

Do you have a stock ported MAF? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No, I just use a stock de-screened MAF.

jmX

Fatten that sucker up. 25 degrees of timing isn't that bad either way. Every time I had detonation I'd lose about 5-8rwhp on the dyno.