Stock MM, Dyno Chart, 234.4 HP 263TQ

[Thomas C Potter]

Thought yall might like to see, hopefully you can read. If not, I'll darken with a pen.

What is interesting is the apparent Air/Fuel ratio change that occurred after 1st run. The faint yellow/green line on the right is the 1st pull. Any insight wrt A/F change??

(tires are 26.9" dia, stock was 28.5)

TP

[ghost]

That's great! Now you have a baseline from which to work!

No insight on the A/F changes, perhaps Dennis can help with that one.

Eric

[TAF]

Thomas,

Much more expertise here than me on the A/F ratio...but, those #s are pretty much in line with what everyone else had as a baseline. If you haven't yet...go here to see my base and progression...http://www.mercurymarauder.net/forums/showthread.php?s=&threadid=2645&highlight=Atlanta+Dyno

BTW...the title of the thread is cheating yourself out of some HP...I see 241-243 RWHP listed.

[RF Overlord]

Thomas:

I'd be more concerned about the change in A/F at around 5000 rpm...

Looks like you're going from a very lean 15 up through 4400 to a very rich 11.5 at 5300 and up...my A/F was almost ruler flat at 13 from 3800 up through 6000...

I don't like the fact that your A/F is 15+ throughout the lower rpm range...that seems WAY too lean...

[MAD-3R]

The apparent lean readings on the AF mix is caused by not letting the computer have time to settle out the Air Fuel from a start up.
I had a dyno pull made that had great HP and TQ numbers, but the AF was off the chart, two weeks later, had another set done, and they came back clean and clear.

When I get home, I will try and find my puls and post them.

[SergntMac]

You're getting top notch advice, Tom, hope it's helping.

I'm not surprised to see such high AFR reads on a bone stock MM, but they are still too high. ECM must be pulling timing back with such high nubmers. Ideal "sweet spot" is 12.5. This can be fixed. If you want to stay bone stock, you can still sign up for a Team Form power tune near you and have your ECM flashed, or, send your ECM out to Dennis. Just bringing the AFR down in the lower end of the pull may get you a few more ponies. Your TQ number are great for bone stock...IMHO.

Two quick questions...What octane are you burining and how many miles on the motor?