Weights of Various M20 parts.

[backtrail69]

During my engine rebuild I had the opportunity to weigh many of the parts I pulled off old engines and my new parts. I thought I would show what I had found. Weights are given originally in oz on a food scale and converted to grams. These aren't 100% Accurate given that, but it gives a good idea.

Individual Weights

Rod (eagle) - 19.7 oz 558.485606 grams
Pin (JE) - 4 oz 113.398093 grams
piston (JE) - 12.13 oz 344 grams

i piston - 13.8 oz 391.223419 grams
i wrist pin - 3.8 oz 107.728188 grams
I rod - 23.6 oz 669.048746 grams

E piston - 14.6 oz 413.903038 grams
E Wrist Pin - 3.7 oz 104.893236 grams
E Rod - 21.7 oz 615.184652 grams

Assembled Weights

eta piston/rod - 40.1 oz 1136.81588 grams
i piston/rod - 41.5 oz 1176.50521 grams
JE piston/Eagle Rod - 35.8 oz 1 014.91293 grams

[nando]

hows it running?

[backtrail69]

Runs great, still pig rich, only have about 20 miles on it and had to go back to school. I am going to run back down in a few weekends for a tuning session pending weather. You are more than welcome to come.

[WillisE30]

Sounds like a party.

[nando]

I would decrease your req_fuel a bit then - mostly to get the extra resolution in the VE table. since it's way rich right now, that's a good chance to do so - if you tune the VE table and later decide you want more resolution you'll have a lot more pain.

[SamuraiSam]

hey chris. by now you probably know about 2-3 thousand times as much about Megasquirt as I do.. seeing as how im going to be behind the laptop for the next tuning session while Isaac drives, do you have any good websites with walkthroughs and info on datalogging (besides megasquirt.info) ?

[nando]

I don't know of any sites, but I pretty much only use Megalogviewer - it's pretty easy to use, but there are a few things that are very important:

-your O2 sensor must be calibrated properly in megatune and MLV
-a good AFR target table is GOLD - it should be smooth and even (14.7 in the low load crusing areas, and whatever you like for full load AFR in the higher areas).
-you will want datalogs of 20-30 minutes for a good VE analysis
-hand tune the idle, and change back anything VE analysis wants to redo (it will just destabalize it)
-start with "cell change" set to normal for 2-3 VE analysis, and move it up to "very hard" incrementally.
-you can leave all your corrections on (ego, etc) but overrfun fuel cut MUST be turned off
-throw away changes with a high weighting less than about 2-3 after your first couple VE analysis
-don't make any changes to the VE table while you're taking a datalog!

after 6-8 "iterations" and incrementally increasing "cell change" from normal to very hard, you should only have to do minor changes to the VE table on the dyno. if his VE table is rich with no lean spikes, and his O2 sensor calibration is good (I'd re-run the LC-1 calibration to make sure it's as accurate as possible), you can rely mostly on MLV only needing minor manual changes.

chris