Deezler's 2003 Jetta TDI Build Thread

[Deezler]

Well, inspired by Daox and some others with build threads on the EcoModder forums I decided I would start up my own here. It will be a place to collectively document all my vehicle modifications and maybe serve as inspiration to keep the progress moving.

This is about as close to stock a picture as I could find. I had just swapped out the original 15" wheels for these heavy 17s.



Once I got the adjustable coilover suspension installed I cruised like this for some time:



Each winter I jack the car up and screw the coilover perches all the way back up for max ground clearance in the snowy months. The original 15" wheels got a set of Yoko Ice-Guard snow tires that have been holding up nicely (but are not too great for mileage).



Last summer I found the EcoModder site and began conjuring up mods for efficiency. 40-44 mpg in mixed driving just wasn't cutting it anymore. I know the EPA revised their procedures to better reflect typical mileage results, but I can't shake the original sticker ratings of 42 city and 49 hwy. I have never beat this highway rating, only coming close on two full highway tanks.

I WILL get 55 mpg on a full tank of mixed driving before I feel satisfied. Getting to the 60 mark would be really nice but I doubt I'll ever have the patience to drive that slow.

[Deezler]

The first steps I took towards improving FE were some light mods to the front end.

Stock:





Finished:



At this point I still had the top grill wide open like a parachute. That wasn't cool. So I took my "sport" style grill and just zip-tied some more coroplast behind it.



Had to leave the corner open for the engine air intake though. Hopefully it sucks enough air to lower the high pressure zone a bit there.



I installed an aluminum skid plate a while back to deal with the potential risks of running such low ground clearance. It's fun to watch my passenger's faces when I clank it hard off the pavement from time to time. Last weekend I snuck back under there and added some coroplast extensions to the sides to help further clean up the air flow. Looks like the skid plate design should be pretty good for aero.

[basjoos]

Originally Posted by Deezler

Getting to the 60 mark would be really nice but I doubt I'll ever have the patience to drive that slow.

If you aeromod your ride, you don't have to go slow to get good mileage. If you know what mileage increase you can get while drafting, that is amount of increased mileage potential you could get out of your car by aeromodding it. This last weekend, I chalked up a 61mpg run through the rain on wet roads while doing a 54 mile dash on the interstate at 70-80mph to get home ahead of a line of powerful thunderstorms. So no, you don't have to go slow to get good mileage.

[Electric Frenzy]

I have a 2004 Beetle TDi with the DSG automatic and we routinely get 48+ in mixed driving. My wife drives it like a race car but I baby it. If I'm driving I can get 50+ easily out of it and still pull 70+mph.

[Deezler]

basjoos with the first reply to my thread, nice! hehe. "If you aeromod your ride, you don't have to go slow to get good mileage". Exactly what I'm going for. However, I am not about to fabricate a boat tail, or nose cone, or ditch my wipers, or anything more extreme like that. I plan to delete my passenger side mirror, make rear wheel skirts, and maybe add VGs or a lip spoiler if I can convince myself that they will help. But thats about it, so I doubt I'll ever break into your FE realm. The highways I drive on put you in the ditch if you go much less than 70 mph, so that will be my normal speed. Most of the time I cruise between 70 and 75 mph.

Electric frenzy, I don't mean to doubt your claims at all, but are those actual tank fill or just dashboard read-out numbers? That is quite excellent mileage for a PD engine. Especially driving over 70 mph with the poor aerodynamic drag of the beetle shape.

Kudos to those pulling down phenomenal mileage. But my engine and vehicle is in top shape, I drive carefully, and this is what I'm getting. So all I can do is work from here.

[SVOboy]

Very nice looking car, keep up the good work

[Deezler]

Thanks svo.

Still going through past mods, just wait till I get some current pics up.

So a while back I performed one of the mandatory VW TDI mods, that being to delete the muffler and run a straight-pipe in its place. The stock muffler is 40 lbs of dead weight, and does little in terms of sound attenuation. After doing this and adding a small turn-down tip, my rear end looked like this for the last 1.5 years or so:



The turn down tip quickly grew ugly as it corroded, unfortunately.

Then right before Christmas some guy in a ranger was nice enough to stop paying attention in traffic and do this:



I really wasn't upset at all, as after a little internet searching I turned up an upgraded bumper, factory painted in my color, from a Jetta "GLI" model. Buying the bumper and a set of side-skirts, I still had $200 profit from my insurance. hehehehehehe.

New bumper fitted:



Had to do some aero tweaking while I had the car in the air.



3 panels and a clear view of the "mufflerectomy" :



I guess I'm rep'ing for Gibson now... oh well, the tip looks good.

[Deezler]

Well, eventually I grew tired of the weight penalty from the 17" OE alloys. Loved the look, but had to move on. The extra weight was really noticeable on acceleration and the tire width made the power steering feel very heavy as well.



Came across some very lightly used (~2-3k miles) Michelin Energy MXM4 S8's in a 205/55/16 size for a good price and snatched them up.
After a painfully long and disappointing search for super light and stylish 16" wheels I settled on these:



Ready to mount on the car:



Comparing weights:

17" setup:
Wheel: VW OEM Santa Monica 17x7 et38 - 24 lbs
Tire: Michelin Pilot HX MXM4, 225/45/17: 24 lbs
Total weight / corner : 48 lbs

New 16" setup:
Wheel: Nexo NT-05s 16x7 et40 - 18.5 lbs
Tire: Michelin Energy MXM4 S8, 205/55/16: 22 lbs
Total weight / corner : 40.5 lbs

Better, but not quite as dramatic a change as I was hoping for. Still keeping an eye out for my dream wheels.

Anyway, got them on the car this past easter weekend. Also cranked my coilovers down 1.25" front and 1" rear. Here they are on the car:



oops, that was a crappy p-shop.



There we go. Too early to tell, but at 45psi the new tires seem to coast much better than my snow tires did (duh).

[Electric Frenzy]

Originally Posted by Deezler

Electric frenzy, I don't mean to doubt your claims at all, but are those actual tank fill or just dashboard read-out numbers?

My dash doesn't have the mpg calculator like my audi does. We generate this number based on the miles driven divided by the number of gallons needed to fill the beetle up to the neck of the filler.

When my wife drives it she's on the turbo from every light. When I drive it I hardly EVER go above 2k rpms and can cruise at 63mph @ 2000rpms. I'm more concerned with keeping it out of boost and under 2k rpms. I get very high returns when I borrow the car for the week.

I should also mention we do very little highway travel but most tanks have at least 2-3 short interstate runs on them.


p.s. We are also fanatical about running Diesel Power injector cleaner w/ cetane booster in the car on regular intervals. I've actually noticed an additional 10-20miles per tank when using it but the cost is too high to justify it every tank.

[Deezler]

Well in that case, nice work!

I usually rev well over 2000 when accelerating, to keep the turbo and intake clean and happy. But 90% of my driving is steady state highway at more like 2500 rpms.

btw I have a 0.658 ratio 5th gear sitting on my work bench, hope to get it installed within a couple months.

You just reminded me to add some Diesel Power to my tank! I am terrible at remembering to add a dash each tank.