This is a great site. I look forward to participating and learning. (I've already learned quite a bit just lurking for a few days.)
My project right now is trying to tune my 1.6L diesel Jetta for optimal fuel economy. I'm rebuilding a different 1.6 engine to swap in, and I'm going to get a taller geared tranny for it as well. I'm also going to put in a free-flowing exhaust, cold-air intake, loose the power steering, maybe do an alternatorectomy of some sort, and anything else I can think of.
I'd definitely like to hear from anyone else on the Front Range.
[QUOTE=SVOboy;39197]The exhaust question is a bit up in the air, but I think most will agree that a colder intake charge is not a good idea for FE.
I agree that this may be the case with Gasoline where greater throttle opening means better volumetric efficiency but on a diesel if you run less air or warmer air through the intake, you end up smoking more which means you are spewing unburnt fuel. I too drive a vw diesel and with more air volume and colder outside air, I am able to turn up the max fuel screw a little so that I can reach highway speeds easier, without sacrificing mileage. More power from more air+more fuel= lower shift points and less throttle, this means I can keep up with traffic better but still keep the gas mileage up. sacrificing too much power in these little diesels is just plain unsafe in the city.
Welcome! Those older diesel VWs are awesome for FE, especially cruising around 55mph. I know people who have got 60mpg or more on the highway with the rabbit (maybe that is a 1.3). I drove a few of the diesel golfs and rabbits when i lived in B.C., Canada, but I didnt know they sold the jetta that late here with the diesel engine.
Probably a grille block will help a lot with FE during the winter, those diesels run cold.
I used to live in boulder, i went to school there until 02. There are a lot of people doing the biodiesel thing there.
It looks like you have some good ideas in the works.
I agree with SVOboy on the colder intake charge, however. Intake air temps are tricky (and it might take some experimentation or fuel maps) to know the ideal temps for your application (especially in the Diesel department).
Regarding the exhaust, the market advertises free-flow, more-horsepower, better FE!!! ...but some backpressure is generally required to maintain low-RPM power (where better fuel economy generally resides). I've yet to do so, but I'll probably just replace my existing system with a stock one, for example.
Best of luck with the swap, and remember we're here to answer any questions you may have. A good bit of info can be found at in the "Busted and Confirmed Mods" thread as you customize your ride for FE.
Cold air intake on diesels is always good. Cold air is denser, and the more air going into the combustion chamber the better -- hence turbo chargers. Diesels run lean, so you can never have too much air, especially at this altitude.