91 jetta versus 2002 wrx

[jstaton]

Okay guys, I joined the TDI-IDI forum because I just acquired a 91 IDI in need of a head gasket (help! I need a head gasket). Part of the reason I am pursuing the diesel is because of the cost of gas. The amount of gas I use in my other car (a 2002 WRX wagon) runs about $2400 a year with a weekly 300-mile commute. The wrx has a chip and a turbo back exhaust and is making around 300 hp at the flywheel, (does 0-60 in 4.6 consistently and a 13.6sec 106 1/4 mile).  If I drive conservatively in mixed city and highway I can get 25 mpg. (I once got 15 mpg driving 400 miles in 5 hours but that is another story) usally if I am driving normally (fast) i get 20
If I drive conservatively in the wrx on the highway (65mph) The best I have gotten 29 mpg. The car now has 88,000 miles on it and I was hoping the diesel will help with the expenses and the mileage on the wrx.
I am looking for 50 mpg with the diesel, and maybe run SVO, but I now I see that you guys are a bunch of speed freaks and i am getting sucked in.
How much power can you get from diesel? how much does the fuel consumption drop? I can squeeze 29 mpg and still run in the 13s in the wrx- what can my 91 jetta with a diesel do?

[SMOKEYDUB]

usually you can keep your fuel mielage with pretty well any mods you do. i have my car done up pretty decently with a 1.6 and still get 780 kms to a tank. i am never easy on my car and i would think with slicks it would do around a 15.7 quarter mile.

[RabbitJockey]

when you fix them up, you can get exactly as good of mileage, or better if you can keep your foot out of it.  which is really hard for me to do haha  :roll: but i'm sure since you drive a wrx, you won't really be impressed by these cars to much

[jstaton]

usually you can keep your fuel mielage with pretty well any mods you do. i have my car done up pretty decently with a 1.6 and still get 780 kms to a tank. i am never easy on my car and i would think with slicks it would do around a 15.7 quarter mile.

First of all a 15.7 1/4 mile is really unbeivable for a diesel car, I think. Honestly no matter how fast your car is there is always a faster one. i am so used to the wrx that i don't even notice the acceleration so that is another reason to have the Jetta.
what have you done to your 1.6? is it  turbo? 780 kms is 484.66 miles that must be around 40 miles per gallon? that is pretty decent.

[RabbitJockey]

i did a 16.5(my first and only run) in hotter weather with a full tank of gas and a bunch of junk in my trunk.

then on another day i went back to try and do better with an empty trunk and half a tank, the weather was perfect for a turbo diesel. cool very damp air and i dunno if it was cause of the xtra power from the cool air or what but now  need a new clutch haha  :roll:,  and 16.5 isn't anything amazing, but i don't really have anything done to my car...

[jstaton]

when you fix them up, you can get exactly as good of mileage, or better if you can keep your foot out of it.  which is really hard for me to do haha  :roll: but i'm sure since you drive a wrx, you won't really be impressed by these cars to much

The mileage and the fact they are so simple impresses me. i am a total gear head and even if they are slower, they are pretty cool. look, no matter how fast your car is, there is always someone that has a faster one. I had never considered a diesel as a speed performer and am intrigued by it all.

so what do you need to do to make them faster? I have a idi, no turbo. what do you do raise the compression? help it breath better? the advantage of turbo cars is the cost per hp. with the wrx for $500 you can reprogram the ecu and get 40 hp, then add an exhaust ($1000) and intake and you get another 35hp. for the money you can't beat it. any more power in the wrx requires more investment for smaller gains (such as adding a bigger turbo, bigger injectors, and a larger fuel pump. this sets you back atleast $2500 for only another 15-20 hp)
Is the biggest bag for the buck with diesel the same? add a turbo?

[Kudagra]

Well I had a 2002 WRX sedan that stock the best I squeezed out of it was 14.0 and yes I got about 22mpg driving like an ass and 29-30 being nice. (BTW dont ever get rid of your WRX. Biggest regret of my life) I do wonder what chip and turbo back you have to get 300hp at the FW. :?  
Ive always been into VWs and Ive come back. Just enjoy it.

[malone]

I like your attitude on cars, jstation

This thread may give you some ideas.
http://vwdiesel.net/phpBB/viewtopic.php?t=4391

A good fuel pump upgrade will definitely make a noticeable difference in a N/A IDI's performance.

Turbos and diesels are almost made for each other.. the TDs are better to start with for power enhancements, but a N/A IDI can still be fun to drive. If you drive nice 50 US mpg isn't impossible, but at least 40-45 MPG may be more realistic. My last NA 1.6 IDI with 250,000 unrebuilt miles consistently made 43 US MPG with harsh city driving and fueling turned up for some power. WVO will definitely do good for fuel savings. Personally I'm considering www.frybrid.com. Greasecar.com's kit looks good (as does their website) but I've heard of some issues with them.

[SMOKEYDUB]

http://media.putfile.com/diesel-jetta

theres my car

[jstaton]

Well I had a 2002 WRX sedan that stock the best I squeezed out of it was 14.0 and yes I got about 22mpg driving like an ass and 29-30 being nice. (BTW dont ever get rid of your WRX. Biggest regret of my life) I do wonder what chip and turbo back you have to get 300hp at the FW. :?  
Ive always been into VWs and Ive come back. Just enjoy it.

I have a cobb ap stage 2, with a helix downpipe, invidia exhaust (280hp) plus an helix uppipe (10hp), (no cats on the uppipe, the aftermarket versions never do) and no cats on the downpipe (this adds 5hp I don't care what cobb claims) plus another 5 for the samco turbo inlet hose) I was seeing 230 hp at the wheels with a g-tech. it was the same as my friends 2004 STI. honestly I didn't beleive the cobb tunning 0-60 times they claim on their web site, but the car runs 4.6 consistanly and a 14.6 quarter. what I have notice after 50,000 miles of this mod is that the gear box doesn't like hard launches above 4000 rpm. i launched a couple of weeks ago at 4000 rpm and it won't shift into second on the run. then wouldn't shift into first for about 15 miles (i thought the gear box was toast)  then it was notch in first, then it went away. don't ask me what happened. I think it bent the rod the gears sit on or mauled a syncro. either way it "repaired" itself, and I have been able to drive it normally. i won't be launching so hard again. the car has 88k on it and I plan on keeping

[jstaton]

Mark M
thanks for the info- very interesting. I need to do the head gasket, i have some oil in the coolant, and the timing belt has never been changed. The car has 146,000 miles on it and I am very impressed by the longevity of these cars, not only do the engines go 400-500k but the rest of the car keeps going and going. I have ridden in allot of VW track and auto-x cars with 200K or 300K miles and they felt like new.
the previous owner of this car was getting 54 mpg (driving at 55mph) I am hoping to have the repairs I am making pay for themselves with the increase in mileage compared to the WRX. (I was given the car for free, it has sat for 2 years before I put a battery and drove it 300 miles to my house)
who knows, maybe I will take it to watkins glen instead of the wrx next year

[RabbitJockey]

definetly go turbo.

[jtanguay]

http://media.putfile.com/diesel-jetta

theres my car

I want my car to be able to do that!!!  :shock:   What kind of turbo is in there? I could hear it spool down on the video... real nice and loud!!!

[SMOKEYDUB]

k24 with no exhaust. mk3 golf downpipe. :twisted:

[veeman]

JStaton...

This might sound odd, but if you'd like your car to be more fun to drive "as is" you might consider upgrading the suspension first.  Mk2 Jetta's handle pretty well out of the box, but if your car has 140k + miles, it probably needs some struts at least.

I'd put something like H&R lowering springs / Bilsteins on it (nothing too harsh for day-to-day driving), replace worn components like tie rod ends and ball joints then get some reasonable tires.  Even with your stock HP, this will make your Jetta a LOT more fun.  The torque of the diesel is ok for zipping around and the suspension really wakes up the car.

For more power, I'd say you should really look around for a true TD engine.  It's a direct swap and you can instantly gain 16 hp or so.  From there, you can up the boost, add a bit more fuel and an intercooler and have some fun.  You'll find this out soon, but TD's were made to handle turbocharging when compared to the NA's...