Help for a newbie

[Slo74]

Hello,

I'm looking for some help in getting my car ready for the track for the 2004 season but am really lost ... :(

My car is a 74 VW beetle with the following mods:

Porsche/VW 914 (Type 4) 2.0l engine (FI originally) now with header and carbs, modified (extremely) Porsche 911 cooling system, external oil cooler with ducting
(originally came with a 1.6l engine), but the 914 block has a VW symbol on it, VW manufactured the block but Porsche modified the heads.

Stock 4 speed transmission

Front and rear swaybars
(car came with front swaybar stock)

Stock shocks front and rear

2" wider fenders front and rear

18x8.5 w/ 235/35 on front
18x10.0 w/265/35 on rear
(car originally came with 15"x4.5" with 165/80 tires)

322mmx32mm front rotors with 4 piston calipers front
309mmx28mm rear rotors with 4 piston calipers rear
(Car originally came with drum brakes from the factory)

This is how the car will be in the next month.

How do I determine where I would be running, or are the mods I have too much ? I could tone down the brakes and wheels if I had to.

Any help is greatly appreciated, I'll add more details if you need them.

Thanks again.

[Dave]

neat car!

In order to classify your Bug, we need a factory curb weight and horsepower rating (for the Porsche engine you're using) as well as some info on the factory suspension design so we can assign it a handling rating (in stock form, not how you've modified the suspension). If you can provide me with this info, it'll make my job a lot easier and then we can proceed to add up all the prep points for the mods you've made and determine what class your car will run in.

Cheers,
Dave

Solo 1 Car Classification Guy

[Slo74]

Wow !

That was quick !

Here are the details you need:

Factory curb weight for 1974 standard beetle = 880kg/1936lbs dry

Factory HP/Torque for 1974 Porsche 914 'GA' series engine, 4 cylinder FI = 95HP/105 ftlbs

Rear Suspension (1974 Beetle):

The rear suspension is IRS (independant rear suspension) that is identical to the Porsche 944 N/A (1983 to 1985). The components are a bolton between the 944 and beetle. The trailing arms, torsion bars are identical. Hope this helps describe the rear suspension. The 944 rear suspension components even have the VW symbol cast on them.

Front Suspension:

Two parrallel beams with a trailing arm attached to each end, with a torsion bar insyide the beam. This suspension is also used on a Porsche 356.

I can change the fenders back to stock and use a smaller disk brake system as well as smaller 15" wheels.

BTW, there are about 10 others in our VW club that would be interested in the outcome. www.boxerautogruppe.ca

Thanks for the help ! :D

[Dave]

great info! That'll make it much easier for me to come up with a fair and accurate suspension rating for your car.

FYI, I believe curb weight is meant to include fluids (ie. brake, tranny, engine oil, etc). The dry weight you've provided isn't going to work for our system of classification. If you can find a true curb weight that includes fluids, let me know and I'll see if I can find an old car magazine that lists the needed data. Once I've got this last piece of info, I can get you a starting PI (performance index) which we'll use to determine what class your car will run in.

Definitely a cool track car you've got there. Looking forward to seeing it out with us next year!

Cheers,
Dave

[AirCooln]

It’s going to be excellent to see air-cooled VW's boot around the track. I have had a couple my self. A 72 Super and a 78 bus with a 2L swap. You can guess where my NIC came from.

Looks like the friendly Mini vs. Beetle rivalry that is rampant in the UK can live in Solo1 next year. Make sure you post up what class you end up in so I can try to make sure my Mini is there too. :p

[Slo74]

Hi,

I think I made a mistake. My shop manual lists the curb weight at 880Kg/1936lbs. I shouldn't have added dry to the statement.

Hope this helps.

Thanks

[Slo74]

ah yes .. the mini vs bug battle ...

I'm pretty sure the mini is a go-kart with 2 doors :D

I remember watching a race a while ago that had a mini in it ... everyone was laughing at the car in the paddock but wouldn't you know it .. it ended up 3rd overall.

[Dave]

Ok Slo74, here's what we've got for a Starting PI for your Beetle.

I've tentatively assigned the car a suspension rating of 45%, compared to the 83-85 Porsche 944 which we have at 55%. I dropped it 5% for the older front suspension design and another 5% under the assumption that the chassis stiffness isn't up to par with the 944.

Using this suspension rating along with the 95 hp and 1936 lbs you've supplied, your car starts off with a PI of 48.7% which puts in squarely in Touring 3.

The header upgrade costs 2 prep points (or PIPs as we call them), the addition of carbs costs 3 PIPs, the rear swaybar is 1 PIP and if the front swaybar is larger than the original stock one then that's another 1 PIP. The fender flares are a free or 'authorized' mod once your car moves up 4 classes from it's starting point, which it will given the engine swap and other upgrades. So no worries there. The large rotors and upgraded calipers are also free or authorized mods once you've moved 1 class, so no worries there either. Same with the wheels/tires.


So based on this list, you've got 6-7 PIPs to add to your starting PI of 48.7%, which would bring your final PI up to 54.7-55.7%. This would bump your car up to Touring 2 (50-54.9%) or Touring 1 (55-59.9%). However, I do have a few questions for you before we assume this is where your car will be classed.

Have you upgraded the springs?
Will you be running alignment settings within the factory specs or having you added camber/caster/toe outside the OE specs?
Have you upgraded the cam(s) or any other valvetrain components?
Has the cylinder head been modified in any way (ie. porting or polishing)?
Has the engine block been modified in any way (ie. overbored, higher compression pistons, different stroke)?
Is the engine equipped with a lightened flywheel, crankshaft or crank pulley?
Have you modified any suspension components such as a-arms, control arms, trailing arms or bushings?

If you answer yes to any of these, we'll have to assign a PIP value to them before declaring a final PI and class for your car.

Cheers,
Dave

[Slo74]

Hi Dave,

Thanks so much for the help with this. Here are the answers you need:

Have you upgraded the springs?

No. Stock rear torsion bars and stock front torsion bars for a '74 standard beetle

Will you be running alignment settings within the factory specs or having you added camber/caster/toe outside the OE specs?

I'll be running the standard alignment specs, but the car has been lowered 1" in the rear and 2" in the front. Due to the design of the front suspension, I can keep factory settings at the front, and the rear is within factory specs.

Have you upgraded the cam(s) or any other valvetrain components?

No, using stock FI cam and stock valvetrain

Has the cylinder head been modified in any way (ie. porting or polishing)?

No, the only modification to the cylinder head was to make a small notch in one of the cooling fins so my cylinder head temp gauge would fit correctly.

Has the engine block been modified in any way (ie. overbored, higher compression pistons, different stroke)?

No, stock block, pistons and stock stroke.

Is the engine equipped with a lightened flywheel, crankshaft or crank pulley?

Stock crank, stock pulley. The stock flywheel for this engine is 13lbs but to do the engine conversion into a beetle, you have to use a VW bus flywheel, which is 18lbs. I can get a custom flywheel that would bring the weight back down to 13lbs. What are your thoughts on this ?

Have you modified any suspension components such as a-arms, control arms, trailing arms or bushings?

No. I was going to install new OE bushings everywhere because the stock items are almost 30 yrs old :D I'm assuming I can do this.

On another note, I've added carbs to this engine because it was way too expensive to rebuild the stock FI, and parts are very difficult to find (30 yrs old). I'm not sure if this makes a difference or not but I can try to find the missing components.

Thanks again !

[Dave]

a heavier flywheel! That's a first ;) There's no reason for us to require you to declare a PIP for the heavier flywheel, but if you lighten it to less than 13 lbs then you'd have to declare 1 PIP.

You can indeed put in fresh OE bushings without having to declare any PIPs. This holds true for any other OE replacement parts you've used on the car as well.

The FI to carb interchange: I was actually mistaken on my earlier PIP number. We charge 6 PIPs under section 6.1.A.4 for this mod, but normally this is done as a performance enhancement rather than a cost cutting measure on a 'vintage' car. Are you using factory VW carbs or are you using a high performance carb system? If you've gone with a stock VW/Porsche carb that doesn't enhance performance then I see no reason why we'd require you to declare the 6 PIPs. To be safe, I would ask you to send me an e-mail explaining why you've gone to carbs so that I can clear this PIP exemption with the rest of the Car Classification Committee (CCC) and the Solo 1 Director.

Anyway, it's certainly looking like your car will run in Touring 2 with a PI of 51.7% (assuming we don't charge you for the FI to carb interchange). With this final PI, you'll actually have 3 PIPs to spend without getting bumped up a class, so if you have some minor upgrades in mind you should have room to do so. I would suggest you download the rulebook and browse the PIP schedule to see what your options are for 3 PIPs or less if you want to bring the car right up to the cut-off for Touring 2.

Cheers,
Dave

[Slo74]

Thank you for all of your help in this matter. I will send you the email explaining the carbs right away.

[Dave]

happy to help :)

[Slo74]

Thanks for the return email Dave.

I'd like to keep the webers so this means I have 6 PIP to add to my 51.7% to make 57.7%

So this means I would be in touring 1 correct ?

Can I make the addition of a proper cam for the carbs and still be in touring 1 ? I beleive a cam change is 3 PIP so that would make it 60.7% ?

Thanks

[Dave]

yes, the carb would take you up to 57.7%. However, we do have a 'Vintage Vehicle PIP Allowance' (section 7.5 of the rulebook) that gives your car 3 free PIPs once it's moved up 4 or more classes from it's starting class (which your car has, since it would start in Touring 5 with the original VW Beetle engine I suspect). This means you could do the cam without moving up a class. So you'd stay in Touring 1, which still seems a little too high a class for an older vehicle like yours on a predominantly stock suspension. I think perhaps we've got the suspension rating too high on your car, even though it shares some elements with the 83-85 Porsche. Let me take this issue to the rest of the CCC and I'll get back to you on it via e-mail, ok?

Cheers,
Dave