Afr @ Wot??

**05gtoautoX** · 03-27-2008, 03:13 PM

I recently installed a ZEX wt kit 100hp. shot and some NGK TR6s. I went driving around with my predator and monitored AFR which is 14.75:1 at anything below WOT and anywhere from 15.5:1-18:1 at WOT. That seems way lean to me, I have not sprayed yet because I want to make sure all is well first. I had a local tuner tune it for me about 4-5 months ago and he said he tuned it for a 100 shot, and that it was good to go. What do you guys think here????

**94 Formula** · 03-27-2008, 03:42 PM

Put the car on a dyno and let them tell you what your real AFR is.

Don't spray the car until you check your AFR..

DW

**Eagle** · 03-28-2008, 07:51 AM

You should be looking to be more in the 11.8-12.2 range at WOT, depends on the RPM range to be much more specific than that. I definitely agree with you, you're running lean (if that AF is accurate).

I'm not terribly knowledgeable on the Predators... are you using a wideband, having it guess from stock narrow band O2s, or does it get AF some other way?

-Eagle

**Frost** · 03-28-2008, 08:19 AM

12.7-13.1 @ WOT OFF the bottle, depending on the car and what it likes

I like to see 11.4-11.6ish on the jug, though with a 100 shot, I wouldn't be scared at 12.0

**Silver Streak** · 03-28-2008, 08:26 AM

Originally Posted by Frost

12.7-13.1 @ WOT OFF the bottle, depending on the car and what it likes

I like to see 11.4-11.6ish on the jug, though with a 100 shot, I wouldn't be scared at 12.0

And here we're told that 12.0 is the optimal AFR for NA cars at WOT... thats what mine was tuned to...

**Frost** · 03-28-2008, 08:46 AM

Originally Posted by Silver Streak

And here we're told that 12.0 is the optimal AFR for NA cars at WOT... thats what mine was tuned to...

If your car was tuned to 12.0:1 then there is a lot of HP left to find; I can't imagine who would have told you that.

Where are you at in NC?

**Silver Streak** · 03-28-2008, 08:53 AM

LOl.. ok so I'm an idiot.. meant 13.0...

Outside of Jacksonville, NC.

**Eagle** · 03-28-2008, 08:56 AM

So you think mine is fat off the bottle, Frost? Thats bone stock motor, off the bottle.

-Eagle

**Frost** · 03-28-2008, 01:06 PM

Originally Posted by Eagle

So you think mine is fat off the bottle, Frost? Thats bone stock motor, off the bottle.

-Eagle

Definitely HP to be found fixing that!

**05gtoautoX** · 03-31-2008, 05:27 AM

had my car tuned and it's running about 12.2:1AFR at WOT N/A, I'm sure there is power to be found in the tune after reading this, but atleast it's not extemely lean.

**Frost** · 04-02-2008, 09:09 AM

Originally Posted by 05gtoautoX

had my car tuned and it's running about 12.2:1AFR at WOT N/A, I'm sure there is power to be found in the tune after reading this, but atleast it's not extemely lean.

I see that kind of AFR before tuning ususally... maybe you have some + LTFTs interfering with WOT.

For autoX guys I tend to lean a bit richer, like 12.6ish:1, maybe your tuner is working along a similar school of thought. Or Maybe he found that your car made the same power from 12.2-12.6ish and left it fat to help further cool the cylinder and fight knock. I am just getting this from the autoX in your name. I'm not into autoX, but I didn't think you could even have a nitrous bottle in the car during a race anyhow.