Thread: Winter affect on kr?

I know ive posting a lot of questions lately.
But need to figure my kr problem.
How true is it, that colder weather causes kr?
Also how much boost diference between the 3.2-3.4"?
Will it be a world of a difference if i run my 3.4 instead of the 3.2?

First, dont worry about posting questions often, thats why this community is here.

Secondly, I would think colder weather would lower KR some since air intake temps would be lower.

wrong syn. completely wrong. everyone and their mom is always like, oh colder air, let's drop pullies. that is stupid.

the colder air causes you to make more boost with more timing, which creates more knock. my car knocks a lot more in the winter.

Originally Posted by SyntheticShield

First, dont worry about posting questions often, thats why this community is here.

Secondly, I would think colder weather would lower KR some since air intake temps would be lower.

Thanx.
Reason is i just came back from scaning the car, and still have kr max of
3-4*.
I was seeing 10.4-10.5 afr@wot with the 3.2", tried to lean it out still kr present.
And i read somewhere that colder weather causes more kr.
Pullied up to the 3.4" kr went down to blips up tp 1* with stock timing.
Thats why i was asking for the perf diference bewteen 3.2-3.4"
Will post the scan as soon as i can.

Originally Posted by Bio248

wrong syn. completely wrong. everyone and their mom is always like, oh colder air, let's drop pullies. that is stupid.

the colder air causes you to make more boost with more timing, which creates more knock. my car knocks a lot more in the winter.

There u go!
Another member that posts the same response i read.

Originally Posted by Bio248

wrong syn. completely wrong. everyone and their mom is always like, oh colder air, let's drop pullies. that is stupid.

Well first, I did say I thought it would drop the KR. Secondly I didnt say anything to the dropping of the pulley sizes. I do understand physics enough to know that would cause higher temps. And I do understand that colder air is denser, however, as stated I was working from the premise that the drastic drop in air intake temps would in turn reduce the overall temps of the boosting and thus less chance of KR.

eh, youd think that way but it's really the other way around for the most part. i thought that too until i scanned my car last winter and it was knocking more than it usually was with the same pulley size.

From what i have been taught, winter is the time for less boost and more timing. that cold air is more dense and shoving more air into it is going to be overload. best thing is to put a few inches on the pulley and toss the timing up.


good luck and make sure you start a slew of cold weather tunes for next year.

Yeah, I guess I misunderstood things a bit, and owe Bio an apology for that.

there are a few tables in the pcm that add timing based on engine coolant temp and intake air temp. i dont know how to get a screen shot of them

How are you tuning your car? I know I just about completely retune my car for the winter. I have to redo the VE tune, MAF tune, and timing gets changed.

Did you start with a stock tune or are you basing it off a DHP file?

My suggestion is to start over with your tune. You have more than enough mods to support a 3.4 pulley. So I suggest that you wipe the slate clean and start over.

Get a stock tune for your car, and make the necessary change the things you need to for your TB/MAF and cam, and injectors if other than stock. You can just copy over your tranny section if you want to, and code section. But start with a VE tune using a stock VE table. Then when that is complete, tune your MAF table. Then work on fueling and WOT fueling. Then increase your timing where you are able.

Originally Posted by Zef_66

How are you tuning your car? I know I just about completely retune my car for the winter. I have to redo the VE tune, MAF tune, and timing gets changed.

Did you start with a stock tune or are you basing it off a DHP file?

My suggestion is to start over with your tune. You have more than enough mods to support a 3.4 pulley. So I suggest that you wipe the slate clean and start over.

Get a stock tune for your car, and make the necessary change the things you need to for your TB/MAF and cam, and injectors if other than stock. You can just copy over your tranny section if you want to, and code section. But start with a VE tune using a stock VE table. Then when that is complete, tune your MAF table. Then work on fueling and WOT fueling. Then increase your timing where you are able.

I can't find my stock bin file.
And my dhp 1.0 was erased with the rest of my info.
I was thinking of buying a zz p bin file and go from there.

Originally Posted by GTP4

I can't find my stock bin file.
And my dhp 1.0 was erased with the rest of my info.
I was thinking of buying a zz p bin file and go from there.

Okay, still not sure what file you are using to tune with then? The tune that is in your car right now, what did it start out as before you started messing with it?

As for a stock tune, they can be downloaded from the DHP forum website (PM JeffsGTP if you don't have access). Or, you can read the file that is in your car now, and get the stock file from that. Do a complete read of your bin in your PCM. Save that and don't delete it, erase it, or write over it. Now, there is an option in the DHP PT to revert everything back to a stock file. Do that and save as a different file name. Now, you can start tuning using your stock file you just created.

Tuning isn't hard if you read over everything (all the guides) and know what you are doing. And it is a lot of careful file management so you can keep track of all your bins, stock file, MAF tables, VE tables, timing tables, etc. But careful file management and naming can keep things straight.

We are tuning with a pt.
I ended up buying a zz p bin file with xp cam and LQ4 tables.
With the 3.2", where i was seeing 6*kr it went down to .5-1*.
The wideband was reading 10.4, so i know i'm running rich.
We are going to scan and send it back to zzp with the bin file.
So they can do the proper adjustments.
Its a progress!