Newbie Questions - IT VW

[NWIT]

The recent GRM articles are the Golf MK III have inspired me to build an IT VW. I've raced a Pro-7 Mazda and also a Volvo 240 in teh past but want to try my hand at putting together my own race car. Based on teh article, the VW seems to be a pretty straight forward build, probably suitable to my limited mechanical skills, certainly a good starting point to improve them.

I am just beginning to explore this idea and have a number of questions:

(1) The article focuses on the MK III, but is there a preference or recommendation as to the model or year for ITB? Mk II vs. MK III or GTI vs. non-GTI? I am looking to build a competative car but have no plans to sink my life's savings into it!!

(2) Am I correct that the IT rules allow 15" wheels for the Golf/Rabbit series? If so, is that preferred or our the standards spec series (13" or 14") a better choice?

(3) Are there any tire preference and/or sizes? I've had good luck with the Proxes RA-1 on my Mazda.

Thanks in advance - I know I'll have a lot more questions in teh futre!

Racerdog

[Bill Miller]

I'm sure Kirk (and others) will chime in on this one. If you're looking at an A3 chassis car, make sure to check for rust! While those that have been here a while know I'm a fan of the A1 cars, they're getting much harder to find, not to mention more expensive. The open VIN rule makes it a bit easier, but not much. Not to mention that the Rabbit GTI got boned w/ the weight.

Others here (chois) run A2 cars, but again, getting harder to find. Youngest one is 20+ years old.

As Kirk mentioned in another thread, the A4 chassis is probably what I would look at if I were to build a new VW for ITB.

As far as the 13" or 14" wheels go, no reason to go that route unless you've already got an investment in inventory. LOTS of choices in 15 x 6 wheels out there. As far as tires, go for the purple crack!

[NWIT]

Thanks for the info. You can find rust free versions of the A3 chassis in the NW for $1500 +/-. The older ones are certainly getting up in age and becoming harder to find. My last two race cars qualified for vintage in the Oregon Region SCCA, so a car built in the 1990s is going to seem real new to me!

[Knestis]

I picked the MkIII for exactly that reason but i started the effort 6 years ago so the chassis is feeling older every day. Rust free - even in the NW, where I used to live - may not be completely rust free in some places that really count (i.e., where rollcages get welded in) so look very closely. I keep looking for the MkIVs to come down in price but they seem stubborn to do so.

If you go that route, all of the 2.0 cars have the same driveline, the only difference being drums vs. disks in the rear. I think disks are easier to deal with but if I were building a sprint car, I'd go with drums for the zero drag ability. There's no reason that I know of that you couldn't start with a VR6 tub, either, if you were to find a good one plus a wrecked 2.0 or some such...

Different years/models have different standard wheel diameters in the ITCS. We went with 14" because the +1 allowance didn't happen until after I'd started buying wheels. That said, you're limited to 6" width which makes 15s a little tough to find.

We run Hoosiers, having discovered that if you take care of them they last as long as shaved Toyos, and are a lot faster. There are other good options out there, I think. Contact Phil Phillips at philstireservice.com for ideas, including the new Nitto that I understand he thinks highly of for budget use. We use 225s on the front and 205s on the back. It's difficult to explain how the smaller tires feel different on the back. It's like they are working better than the wider ones did - which NEVER got up to temperature and were substantially LARGER in diameter from pick-up at the end of each session - but they don't stick as WELL so the balance is better. If that makes any sense...? We emphasize endurance racing but if I were focusing on sprints, I'd look at the 205 all the way 'round. (Note that Hoosiers are wider for any given size than Toyos.)

A few other thoughts...

** Particularly if you're on a budget, don't be seduced by super-low final drives. We've tried them all and have decided that the car really goes best if you drive it like a truck - 3000-6000 rpm.

** We've ended up with 500# springs and no bar in front, and 700# springs and three bars in back - the a modified stock on, the Shine "race" bar, and a custom unit from Cameron Conover (now at RennGruppe Motorsports in Lexington, NC). Different people will have different opinions on this subject, of course...

** We have a lot of cage, a big fuel cell, and scraped all of the undercoating off the car; and are within about 40# of the ITB minimum with a 190# driver. You CAN get to the minimum if you work at it. I don't think there's enough of a weight penalty in the 4-door to prevent a person from using one, particularly if it means getting a cleaner tub.

** Conover will tell you that there's a lot to be gained with programming. We use a custom chip in the OE ECU but he's agitated for Megasquirt for the past three years...

If you have any specific questions, get in touch.

Kirk

http://www.it2.evaluand.com/gti/index.php

[NWIT]

Thanks for the input. The more I check Craigslist the more I am leaning toward an A3. I checked out your website and pics of your car before posting my questions. you have one good looking rig!

Not let me ask a few more potentially ignorant questions:

(1) What do you mean by super-low drive? Is this the same thing as an LSD? If not, what type of LSD would you recommend?

(2) Did you use front and rear strut tower bar?

(3) Any general comments about the GRM articles? Would you feel comfortable installing the equipment they mentioned? (I do know the wheels are too big - 15x6 is basically the limit.)

Thanks again.

[Knestis]

1. I'm talking final drive gear ratio. The stock one is a 3.67. We've tried a 4.25 ("lower" ratio so the engine is turning more revs at any given road speed) and there are other fancy-pants "Motorsports" ratios that are even lower. We've settled on the 3.89 as the best answer but that's influenced by track speeds. In terms of differentials, I've used an open diff, clutch-type (Kaaz), gear type, and welded (now a real spool in the one that's going together currently). I prefer the spool diff for sprint racing and the gear diff for enduros with renters.

2. Front = no. Too crowded under the hood and on the strut tops to worry about it. Rear = kind of. We have a transverse element in the cage between the rear downtubes.

3. I haven't seen the GRM article but am interested. I am a huge KONI fan, use Recaro seats pretty much exclusively, and really like MOMO steering wheels. We use a Race Technology DL1 data system and Dash 3 display. Springs? Who cares. There are several good brands. We like Hoosier tires but I know there are other good options, depending on budget and sizes available. What other equipment would be branded...?

K

[Flyinglizard]

13in wheels dont fit the brakes of the Mk 3. The Mk3 covers the weight better than the Mk 2, but be ready to megasquirt it right off the bat. Cheap tires are SM size ,but the shorter the tire the faster the car in the VW world. The stock gear box, welded or a good locking diff works best. If you are new to FWD, try is stock trans and diff for a year. If you have lots of races,welded is usually fastest and the most fun to drive, IMHO.
Running the legal stock cam and valve springs limits the rpm to about 6200. If anyone goes by you with the 4.22 diff at 7000rpm, those parts are suspect.. HTH, MM

[shwah]

As Mike says 13" wheels won't fit over the 10.1" front brakes, thus they were never offered from VW on the car so not only don't they fit, they are not legal...

The A2 can be competitive in real life if fully developed, but is classed at a disadvantage. The A3 classing equates to an assumed 22-23% gain over stock hp in IT trim, the A2 classing is based on an assumed 30% gain (my experience is that 25-27% may be possible, but I do not have 'actual' stock numbers to validate gains). Note that the A3 has a better flowing air flow sensor, thin stem valves, a better flowing head and bigger brakes. The negatives are a bit more frontal area and less good gearing compared to the A2. In apples to apples builds the A3 will be faster.

Also, as noted the youngest A2 is old at 18yrs.

[Tim Dugan]

Now if i was building a new race car i would try to find a 4 door mk3. I like touring car look and i think they handel a little better longer wheel base unless u like to hang it sideways build a 2 door. Parts are easyer to come buy and cars are way more available. they are very easy to work on and need minor maintenance between races. Billstein struts work great with the cars i use 650 lbs springs up front 500 in the rear no bar up front and nothing in the rear either. building a tranny with a wave trac diff right now. Tires and wheels very old wheels that are as light as u can find them i run 225 hoosiers and run them till these nothing left they seem to hold on till the end i turned the fastest laps( 1.20.1) at nh all season as they were getting ready to show cord. And drive the snot out of it they love it. Hope your car building goes well post pics i alwasys love to see a buid

[JoshS]

Now if i was building a new race car i would try to find a 4 door mk3. I like touring car look and i think they handel a little better longer wheel base unless u like to hang it sideways build a 2 door.

4-door Golfs have a longer wheelbase than the 2-door?

[shwah]

No. They don't. All A3 chassis cars have the same wheelbase.

[Bill Miller]

4-door Golfs have a longer wheelbase than the 2-door?

What Chris said. Doesn't matter if it's a 2dr or 4dr Golf or a Jetta, it's the same chassis. A3 Cabrios too.

[NWIT]

I appreciate everyone's comments; a very supportive community here.

It appears a A3 Golf is probably the best choice value-wise. I am in the car search mode right now, found a few 4-doors, but I like the extra width a 2-dr gives - easier entry and exit for a big guy.

Out of curiousity, any comments out there on the GRM articles? Except for wheel widths, it appears the improvemetns are following IT rules.

Thanks again.

[shwah]

Yes he was following IT rules. Actually consulted the IT VW racing "community" before and during the build.

General comments/suggestions:
As Kirk noted there are real gains in the ECU.

One of the tricks to getting down to wieght is building the cage the right way, such that it requires the removal of the heavy reinforcement beam under the dash.

The motors, just like the 1.8 before them, are pretty much tractor motors. Shift points of around 5800-6000 seem to work best.

Welded differential is cheapest, and no other solution has been proven faster to me. Go with VERY aggressive front brake pads if you go this route.

Techtonics makes a pretty good off the shelf header for these cars, though you may find slight gains in area under the curve with a fancy schmancy custom header. This should not be needed with the favorable power to weight ratio.

The floor boards of 99% of A3 cars have rust around the side and rear edges - even if you can't see it. The undercoating and sound deadening disguises it. Don't let this scare you though. My car has holes in the floor too. I keep putting "patch the floors" on my to do list, but it keeps not getting done.

The earliest versions of this motor had forged cranks, but honesty this does not matter for our prep level. Don't get too caught up in trying to get one - unless you find that they are a lot lighter or something (which I don't know).

If you are able to - go find one that has been built already. You will save big $$$ in this economy.

[NWIT]

Chris

I know, I know I really should buy one.

But I've always been on the sidelines, have had two race cars, but other people did all or most of the work on them. I do not anticipate building the cage - I'd leave that to the pros - but the suspension, brakes, tuning, exhaust are the things I need to learn, if for no other reason than my own satisfaction.

You need to do it once and I want to be proud of the finished car.

Still Chris, I know you are right!

Walt

[Knestis]

...One of the tricks to getting down to wieght is building the cage the right way, such that it requires the removal of the heavy reinforcement beam under the dash. ...

Negatory, good buddy. I left said piece in because I was confident that the chassis would be stronger with it bolted in place (massive hardware!) than it would be with a cage tube in there instead.

Forged crank is substantially heavier than the "weak" one. Remember that it's diesel approved so it's not going anywhere.

Obi-schwah speaks the truth, young Jedi. Look into your heart. If you are fibbing to yourself because you think it will eventually be cheaper, or if you don't have the $$$ saved up right now to buy a car so figure you can sneak up on it over time, you're setting yourself up for disappointment.

I haven't seen this alleged article but if they say ANYTHING about cost, they lie.

K

[NWIT]

To build or not to build, that is the question . . . . whether 'tis nobler in the mind to suffer the slings and arrows of someone elses mess or create your own . . .

Master "Kirk" Yoda, I fully concur. However, even after I purchased a prepared Pro-7 car I still had to sink $1500 into to fix a myriad of problems that emerged (or were not fully disclosed).

My plan is for a 2-year build, following the guidelines you established on your "Recipe" on the IT2 Initiative. this will give me time to work with the car and improve my mechanics.

But I'll still look at the classifieds . . . .

[Flyinglizard]

The Mk 3 is about a $10K build, doing most of your own labor.And not restoring the car first.
You can buy many Mk 1or Mk 2 for $3K that already work and have plenty of good stuff. It will take you a long time before you get the Mk 3 up to speed. Dont bother with the stock computer. Go right to the Megasquirt and stand alone ignition. Convert the Mk3 dist to the 4 window Mk 2 wheel. Wire around the ECU to an old style box and coil.
I have a perfect MK 3 Jetta smoothtop shell for 300$, no rolling parts. 34604/6812 FL.

[Conover]

Yes he was following IT rules. Actually consulted the IT VW racing "community" before and during the build.

Except for the short shifter, and the urethane motormounts, and this and that. . . .

He's building it for autocross, unfortunately. . .

[Conover]

Actually, with the right chip the stock ECU is pretty damn good.

The cast crank on the mk3 is about 3lbs lighter than the forged crank, and the OBD2 camshaft is just a touch better slightly more lift and a better lobe center.

The OBD2 engine has just a touch more potential because of that, either OBD1 or OBD2 engine management is fine, with the OBD1 being somewhat more persnickety about what it likes.