I filled the tank last night after driving it 175 miles over the previous two weeks. It took 8.9 gllons of gas, which works out to about 19MPG. I spent at least on hour of that operation time with the car idling in the garage tuning, so the car probably is currently getting 21-22 MPG. I feel good about this. I have not tuned for power yet, as general wisdom seems to be to get baseline drivability issues worked out first. The goal with the turbo thing was to build a reasonably fast car that is also economical. While it is not as economical as my Toyota, I feel like I am headied towards reasonable economy now. The project is looking like it can be a considered a success. And, there is alot of room for improvement through tuning yet.

The car still needs to warm up a minute or so before it is completely drivable, as it goes instanly lean and stumbles when you touch the throttle at an idle when it is dead cold. I have played with the warm up acceledration enrichment trim tables, and improved it some, but noticed as I was derving around yesterday that when cruising at 1200RPM in fourth gear, and open the throttle a little it will also go way lean at that point. This would indicate that the VE table at low RPM and lower map readings need to be enrichened somewhat. I know this would improve the drivability, but also would improve this cold start thing as well. The warm up trim talbles apply their math to the base VE table, and if the base VE table is too lean, then it stands to reason that the warm up trim table is going to be too lean also.

The general approach right now is to change things just a little at a time, and then evaluate the change for awhile.

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Sounds like progress! Keep up the good work.

Lou

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Home of Slant6-powered fun machines since 1988

Glad somebody turned a corner this week!

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Yeah....Im the one who destroyed this rare, vintage automobile.....

good to see your doing well, is this with the MS ecu. My dad got one for me, but he needs a new motor in his 49' GMC more, so this summer I'm building him a 250 and wanting to use this computer to control the efi. Thanks for the info.

I started with MS, and then switched to Accel. The ACcel is a very, very good unit, but the instructions are very poor, and factory support was not so hot. The MS stuff has so much support that you will absolutely be able to get it to work if you apply yourself some.

I mentioned the MS site as just a place to go for tuning tips.

Sam

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Sam It's good to read that your build up is going your way. I've enjoyed watching your progress via this forum, and look forward to reading more about your build. I must also say that I have a picture of your car on my laptop at work and everybody stops when the slide-show gets to your car. What I'm getting at is this, great car and keep chipping away at getting the timing curve set.

Sean

Thanks! That was kind of you to share that little bit of information. You know, I have had fun with this car whether anybody else thinks it's cool or not, but the success I am experiencing now is in large part due to the collective wisdom of this forum. It's been a joint project in many ways. Pretty much every thing on the car, with the possible exception of the plastic front clip, and body work, has been discussed on this forum or in personal e-mails to members of it. If you go back to the early years of the forum, I was posting as Dartvader. I have asked some pretty dumb-dumb questions over the years.

So in a real sense it is your car to enjoy too, or at least take some pride in on your computer. It is nice to have the wisdom of my keeping it affirmed by others, but the car kind of does that as well, all by itself.

Right now I am getting the cooling system squared away, which hs been an awkward combination of technologies. You can see the thread about that on the engine section.
Sam

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