Zink Formula Vee

Will you be splitting the sway bar to tune it side to side or is that not legal in vintage?

Bob was kind enough to drop his car at Eclectic for a little while so we can get some ideas as we go into the home stretch.  It's an earlier car than ours and he's been running it for about 15 years.

Meanwhile, I've been painting wheels. 

We started with 10 wheels and used the best 8 as we'll have two sets of tires.  My understanding is that these are 1966 only wheels as they have the wide five pattern and the slots.  Earlier wheels don't have the slots, which should reduce weight and cool the drums better.  I have a 1966 Beetle with these same wheels.  Do I have this trivia correct?  Anyway, I had them sandblasted ($40 each) as it would take forever in our cabinets.  I primed them with PPG DP48LF white epoxy primer, again 2:1:1 with DP 401LF and DT 870. 

Then, our paint supplier let us down on the silver paint.  I ordered some modern Nason economy stuff, but they supplier didn't send the activator and kept promising it for the next day.  Supply chain and labor shortages I guess.  Fortunately, I had some DuPont Centari 5580A (1975 Ford Silver) that I've used for wheels forever and love it (no longer available, though).  I had just barely enough to do the wheels and they came out looking very nice.

The chrome wheels that Bob runs (as do many other FVs) are aftermarket 4.5" wheels and the stock ones we're running are 4".  We'll probably try the wider wheel back to back with the stock ones at some point.  They're on backorder from just about everyone right now, so we'll wait until later for that.

Wheels.....1966 and 67 are the same with slots , 

but they also use a different flatter hubcap ,

that is not what you have !

see the rectangular indents with the drilled hole , these are used to mount hubcap clips , which the hubcap pushes over.

The solid wheels will have the same indents,

the slotted wheels you have are like 356 Porsche rims , or the Brazilian chrome rim copies.

Probably too late but can you see any date codes on the face , or a company name ?

In reply to californiamilleghia :

I figured you'd chime in.  Thanks!  You know your trivia.  There are date codes and I can still probably read a few of them.  I put the paint on really thin as I want to be able to watch for cracks. 

I was wondering about reproductions or other things as some have holes for the hubcap clips and some don't.  I'll report back.

I should have known some of this as my 1966 Beetle has those flat hubcaps and no clips, I just haven't looked that closely at the wheels.

Of course, this old photo doesn't show the wheels or hubcaps, but trust me, they are there.

Looking at your photo I think you have 2 and 2

the front left rim is a 66-67 rim with the dimples that hold on the hubcap 

vwcorvette (Forum Supporter) said:

Will you be splitting the sway bar to tune it side to side or is that not legal in vintage?

I haven't thought about it.  I doubt it's legal. I'll report back.

The original 4" steel wheels are the desirable ones.  The chrome 4.5" wheels are significantly heavier and the fast folks don't run them.  The really desirable version doesn't have the raised lip which blocks the brake inspection/adjustment hole in the drum and makes brake adjustments (which you have to do after every couple of sessions) easier with the wheels on.  You can run with some pretty significantly bent wheels as long as you put the really bent ones on the back.  I have managed to actually warp a drum with a bent wheel, so don't go crazy.

In reply to Berck :

I was wondering about weight with the chrome wheels.  Aftermarket steel wheels tend to be heavy and chrome ones even more. 

Here's a photo dump of some of the stampings on the wheels:

Only two of them have VW stamped on them, and those don't have any other numbers or codes except 4Jx15 on them.  The other ones have the other symbol or nothing, but do have some things that look like date codes.

So I think I have 6 repops and 2 VW wheels.  Doesn't matter much as long as their straight enough to use, which they are.

Maybe californiamilleghia can interpret so the trivia pool gets a little more filled?

californiamilleghia said:

Berck said:

I highly recommend some sort of system to detect when you've lost the fan belt.  If you're running a CHT gauge you might notice it in time, but you'll have roasted a cylinder by the time you notice an increase in oil temp.  I run a universal pressure sensor tapped into the fan shroud calibrated to about 1" of Hg.  I think.  Unless it was 1" of H20.  Piped to a giant warning light on the dash. It flickers at idle .......

Do you have a picture of how the sensor mounts .? And how you  wired it ?

Sounds like a great idea for any air cooled VW - Porsche - Corvair etc
 

Thanks

So, here's a photo of the silicon tube tapped into the fan shroud.  The beetle has the throttle cable going through the fan shroud, so I just shoved a rubber grommet and barbed fitting into one of the existing holes.

I put the actual pressure sensor on the driver side of the firewall to protect it from heat.  It's a completely generic piece made with HVAC in mind.  It has both a pressure and a vacuum side, and allows for either NO or NC wiring.  I wired a light through the NC side, and when the pressure trips high enough it disconnects the light.

In reply to Berck :

Thanks , it would be interesting to hook up one of the motorcycle vacuum carb testers at a few spots on the fan shroud  and see  what different areas of the shroud are pulling vacuum.

The tester I had was for a Honda 750 with 4 carbs

In reply to Berck :

Cool, thanks for sharing.  As I said before, we'll have a big generator light on the dash, but if we ever gut the generator, your setup is cool.

The car will be at Gingerman in nine days.  We think we're in good shape and plan to have it "done" this weekend so we're not doing any last minute work.  Here are some updates.

Since I'm the advisor for Hope College's Formula SAE Team and Theo and Jack are former team members and captains, we thought it would be good for the team to see an alumni car at their practice a few nights ago.  Of course, we also used it to make some shakedown runs on the car.  We'll use our enclosed trailer for racing, but the open Zink trailer is great for local runs like this.

It was 40 degrees and windy, so we didn't get any heat into the tires.

The team had their first drive of the year in their 2018 car (shown) and their 2021 car (not shown).  

After the shakedown, which went well except the engine was running fat and loading up, we went to set the ride height. While it's pretty easy to put adjusters in a VW beam, they're not legal. 

As a result, ride height is adjusted by using a spare trailing arm mounted backward, a pipe wrench, and a long piece of tubing.  We bent the torsion pack past its elastic limit so that it would take a set, then checked ride height.  After three iterations, we had the front end where we wanted it. Maybe someone will chime in about why adjusters aren't allowed.

The fuel issue ended up being a bad needle and seat and the carb was occasionally flooding. Easy fix, fortunately.

No pictures, but we took the car to a chassis dyno yesterday (DynoJet 248) and had a good session.  We made 12 pulls and tried some minor tweaks.  We also tested a spare carb and some other bits.  Since we hear these engines make 50-60 HP at the crank, I was expecting high 30s at the wheels.  I know a lot of people say 15-20% driveline loss, but I find with a lot of small HP cars it's more like 25-30HP off the peaks as opposed to a percentage.  I've made thousands of chassis dyno pulls and a few times had engine dyno numbers too which backed up my 25-30HP theory.  However, I was pleasantly surprised when we made more than 40 WHP at the wheel with very high repeatability.   I'll take more WHP than original rated flywheel HP any day.

Bob said we could weigh his wheels, so here's a rear, chrome reproduction vs our rear wheel.  Bob's tires were maybe half used and ours are new, so his tires may be a little lighter.

27.50

27.5-25.85=1.65 difference.  The other wheels/tires were in that same range.

I planned to wire the car up with all VW color codes and ordered the wire to do so.  Then the supply chain finally did us in and the wire isn't going to be here on time.  So I'm making up a loom out of more standard colors for now. It will probably stay in the car until we blow it apart for paint and other cosmetics.

We're not loving this master kill switch (Longacre, usually very good stuff), so we may change it.  It's just a little rubbery feeling, not as precise as other ones.

Generator and engine wiring.

Starter and rain light.

Voltage regulator.  It's harder to find the old-style coil-type regulators.  Most of the VW suppliers sell fully electronic ones that seem reliable, but we figured this looks the part and will be repairable if it gets zapped or wet (plus we'll carry a spare).  We got it from NAPA, believe it or not.

Not quite done here, but we've made a little switch panel with the starter button, ignition toggle, rain light toggle, and remote brake bias.  We'll have two fuses--one for ignition all by itself, one for everything else.  We don't want anything else on the ignition fuse that could stop the car from running.  I'll post pictures of this all finished, plus the gauge wiring, in the next few days (should be done tomorrow).

And here's a detail. I have a friend that worked on the LeMans Viper program for Roush back in the day.  He taught me many things, including this trick for tying wiring up.

You use two zip ties and make sort-of an 8. The little distance from the mounting surface resists chafing or other potential damage to the wiring.  It also makes troubleshooting and service a little easier.

Here's a closeup.

The "rubbery" feel of the kill switch might be a good thing.  There are a lot of vibrations in the chassis, and some say the flex helps keep the vibes away from the contact surfaces inside.

A tech inspector might tell you that you need to insulate the terminals on the back of that switch.

YMMV

I don’t have a definitive answer for the adjuster question but I have a saying that may cover it. Sometimes your greatest strength is your greatest weakness. Strength is a rule set that dates back 60 years and very slowly evolves, the weakness is the rule set doesn’t evolve.

Purple Frog (Forum Supporter) said:

The "rubbery" feel of the kill switch might be a good thing.  There are a lot of vibrations in the chassis, and some say the flex helps keep the vibes away from the contact surfaces inside.

A tech inspector might tell you that you need to insulate the terminals on the back of that switch.

YMMV

We're going to insulate all of those bare terminals.  I just have them uncovered now for testing/troubleshooting.  Good point on the kill switch, too.  Thanks.

The punch list continues to shrink.

Added a low oil pressure warning light and a generator light.

Wiring is pretty neat, maybe needs a little more tidying.

Of course, since the wiring is done, the wires in VW colors showed up. It will get used in the future. 

Theo and Jack added nerf bars to the rear trailing arms.

Back on the scales as we move to final alignment and setup.  We're six pounds over the minimum weight.

The punch list is nearly punched.

Jack mounted the mirrors from Pegasus Racing.

Theo mounted the catch tank, also from Pegasus.

I sewed up this little 4x4x1" headrest.  We're mounting it with Velcro but I put a tether on it that we'll screw to the firewall in case the Velcro lets loose.

 Jack and Theo aligned it and dialed in the bump steer.  We don't love the big spacers, but that's how everyone does it because the tie rods would hit the frame rails on full bump if they were higher. We put a long bolt through the hollow spindle with a double nut and a locknut. It has a little bit of freeplay.  The idea is that we check it and if the freeplay is gone, there is an issue.  And hopefully, if the spindle does break, the bolt will keep it from coming off the car. Apparently some guys use leftover head studs, but we didn't have any so we used the long bolt.

Very close to done, so we won't need to thrash in the few remaining days. That will give us plenty of time to organize tools and spares.

The exhaust looks a little long--not sure about monoposto, but at least the SCCA GCRs say it can't extend past the bodywork, and the body length is specified as well.  You might be fine; I can't tell from here:)

In reply to Berck :

I think you're right that it's a bit long.  Hopefully, they won't make us cut it back for the first event.  We plan to make a new one that goes 2-2-1 and will be shorter.

Nick came over tonight to put the numbers on. 

He said that the supply chain has made it hard to get black or white vinyl.  His vinyl guy had to borrow from another shop.

We kept it basic for now as we plan to paint the body a different color in the future.  It's just black gel coat right now. Jack and Theo wanted to use "1" or "11" or a variation of "7" since those numbers would weigh less, but they weren't available.  So they went with "66" as they figured the weight was at least down low.

Meanwhile, I dealt with a charging issue that turned out to be a bad brand new voltage regulator.  I called a friend who had a couple of good used ones.  I tested both and they worked, so we now have a spare. 

No good deed goes unpunished as the now-working charging system was giving us feedback so the master shut off switch didn't master shut off anymore.  We switched to one with the extra connectors to isolate the charging and ignition system and all is good.  Plus it just feels better. And we taped it so it's ready for tech on Thursday.

And we're off...

We packed all the spares and tools last night and loaded mid-day today.  Jack and Theo headed out to Gingerman (about 45 minutes South) today to get the car through tech (it passed).  I'm heading down in the morning.  Jack's in driver school tomorrow and his first session is at 8:00am.  It's going to be 45 degrees in the morning with a high of 60. Spring is sort of starting.

Jack and the car did well at the VSCDA driver school today. 

We had to tighten the right rear axle nut a couple of times, had a flooding issue on left turns solved by greasing the top carb gasket to get it to seal better, and had to add a couple of shims to the generator pulley to stop a rattle.  Very happy to have so few issues.Hopefully the car will stay this reliable.

Tomorrow starts the racing with an 80% chance of rain. Sunday's forecast is more promising.