Porsche 914 First drive... datalog

yarin · Post by **yarin** » Sat Apr 15, 2006 5:50 pm

I finally got the car running, fixed a few small issues. I attached my datalog and settings. A few questions:

What should my target AFR be for idle?

I see my minimum PW is around 2.0ms. I'm using stock 914 2.0 injectors which are very large for the applicaiton. I don't have any idling issues, nor do i have an off idle stumble. Do i leave it as is?

The car is unusually slow, acceleration is smooth but almost nonexistant. I checked the timing and its dead on. Any suggestions?

Someone please review my datalog and give me your first impressions.

MS II V.3.0. fuel only, stock dizzy with mechanical advance.

bertelli_1 · Post by **bertelli_1** » Sun Apr 16, 2006 7:00 am

I've had a quick look at your datalog - don't worry about your AFR at idle, just adjust the map in that area to acheive the lowest MAP reading. I think your PW is too small although on the datalog I couldn't see what it was doing at a steady idle. Check your AFR at full throttle and don't be scared to try it richer. Enjoy!

bluetrepidation · Post by **bluetrepidation** » Sun Apr 16, 2006 7:25 am

Do you have a CAT installed? I'm guessing not. If not you can run lean at idle to conserve fuel. What I did was tinker with the VE table in my driveway till I was happy enough to try and drive it. I set the high RPM and high MAP areas to run SUPER rich. Rich under load is better than lean so you don't overheat things. Then I set up autotune and found a friend to keep an eye on things. We went out starting slow then onto the highway for two hours. I would slowly increase the throttle till the engine started surging from too much fuel and let autotune drop these VE values down. After about an hour of tinkering I was pulling to 100 MPH. Now my VE table isn't to shabby. I'd also look at programs to help fine tune things like MSTweek 3000 or VexME. I haven't had any luck yet on those myself though.

Read this:

http://www.megasquirt.info/megatune.htm#autotune

A.J.

bluetrepidation · Post by **bluetrepidation** » Sun Apr 16, 2006 7:33 am

From what I can see looks like your accel enrichment needs some work but I wouldn't worry too much about that till you get the VE able buttoned up. Otherwise not to bad.

A.J.

yarin · Post by **yarin** » Sun Apr 16, 2006 7:31 pm

Just a quick update on whats going on...

I found out that two of my injectors are not firing. No idea why. I checked at the wiring harness end and i see +12V and continuity to the relay board. I switched to the other injector bank and the car still fired. I'm amazed the car ran with only two injectors working. Maybe its a bad connection to the injector. Who knows, i had these injectors cleaned and flow checked so i had assumed they came back good.