So since it seems like we lose a few motors every winter to the cold, I was wondering if you get a cold weather tune dialed in for a really cold day, wouldn't it be okay to get on it year round? Wouldn't it be less of a chance to have weather-induced detonation?

How's that affect 1/4 mi. times when you run it in the summer time? Would it just be too rich and hence less power?

I did a search and there are just so many people saying "oh don't get on it when its cold out..." and it just seems pretty stupid not to be able to jump on it anytime you get the feeling you want to.

Thoughts/Feelings?

 

Specifically I don't know....

However, Paul at REM made my "race" side of the chip for bone cold days. (35 degrees is what I told him)

In the last two years I've noticed that with a hot motor on a warm-to-hot (above 65deg) day it'll run quicker on the street side. No matter what fuel I'm running too.

Rich

 

It was 44deg this morning on my overhead console when I left the house, I am running a very rich conservative tune becuase it is getting colder.

On this tune in warm (70deg) air my truck makes 14.5 psi and A/F is in the high 10's low 11's. I have very accurate peak hold guages and wideband A/F meter in my truck at all times do I have good idea whats going on.

Well this morning I saw peak boost 15.5 and A/F ratio's in the high 11's, The truck was running a .7 leaner in the cold air. Now if I was tuned for a 12.0 A/F ratio I might be seeing nearly 13 to 1 in really cold air under boost.

13.0 air fuels, 15psi of boost, and pump gas is recipe for ventilated block even with low timing.

Bob

 

I agree with what you guys are saying about the a/f ratios, but I think that timing has alot more to do with it. In most cases if you run less timing, or more fuel, you will lose hp, depending on how much extra fuel you run, and how much timing you are running you could probably lose around 15hp or more.

 

 

Just get a flip chip or a couple tunes tunes made for the Predator or SCT 9100 and take advantage of the weather year round.

With a "safe winter tune" in 45* weather I run about the same as my "summer tune" in 80* weather. Now my summer tune runs 2 tenths and 2-3mph faster in any given weather. That translates into a 20-30hp and tq difference between the tune. The only difference between the tune is 3* in the timing and splash of fuel :santa:

 

Great post Bob Tompkins. I've always wondered this.

Now, I'm wondering what the most timing at WOT people are running in 40-50 degree weather and NOT blowing up their motors?

I'm also wondering, is the 10% that the Predator can add probably enough to add for a 40-50 degree winter air?

 

You know me. 16* is all I can run in the winter, and that's pushing it IMHO. I run 18* untill it drops below 50* or so then it's the old 15* tune.
I can't wait untill summer/spring. After the supercooler install I'm going to push the timing up to 20* and she how she reacts!! I figure 18* now in 50* degree weather...why not not 20* in 70*+ weather?

 

This is pretty good information...


Thanks!

 

Think about it for 2 seconds.
you have a $30,000 truck, go to a MAJOR tuner and have it dyno tuned. It's well worth the money.

BTW: I drove my truck 4 months this year. Michigan had a Rainy summer.

 

Actually, I've paid for custom tunes since the day I got the Predator... 3 different tuners...then it went BOOM... and then I had a new motor built. So I definitely know the importance of having a tuner.

I just think that since a tuner can't be with me tweaking my tune a little here and there since I don't live close to one that I'd rather make sure they leave some power on the table and put some reliability back in.

I'd rather have a 650 hp capable motor put out only 600 hp or even 575 hp and live to go WOT another day!

 

I couldn't agree more.
I told my tuner I wanted dependabilty and longevity, especially if I left some power on the table.

Exactly what I got and I'm still at 435/522. crap.. it might be 422/535....

Doh... Oh yeah it's in my sig

 

I agree

 

I tried 18* recently, and I can't even get away with THAT!

I'm at 17* right now.

Going to the track tonight, hoping to nibble some ET off my previous 12.92 (F1's).