Flat Out At Daytona in a Karmann Ghia

VW underneath a classic Italian body design.

Moderator: FJCamper

User avatar
FJCamper
Moderator
Posts: 2690
Joined: Wed Nov 14, 2007 5:19 pm
Location: Birmingham AL

Flat Out At Daytona in a Karmann Ghia

Post by FJCamper » Sat Nov 18, 2017 8:51 pm

Image

Ghia in the infield "Horseshoe", 3rd gear, flat out. Front inside tire lift is classic to VW's and Porsches -- including 911's. The problem is too much front roll resistance. In this case we're on very sticky Hoosier "Speedster" 185/65x15 racing tires and no rear anti-roll bar.

Sun, Sea, and Speed ...

07Nov17; Tue. We arrive Daytona Beach well before noon. The weather is excellent, 80° F. and a light sea breeze. Barret, Jamrod, Jim
Allen, and I pass HSR registration, and get the Ghia through tech. No problems. We are given garage 34, Gold side.

As usual, the Ghia is a hit and a curiosity. One woman says it is too pretty to race. We get more passerby glances and attention than the crowd of 911's in the garage around us.

Image

Once a year, HSR takes over Daytona and runs its own sprint and enduro races for a week, filling the grid with original, famous and famously expensive sports cars. Normally, we'd have small under 2-lire sports cars (Brit, Italian, and German) competition, but not for Daytona. We were the only one in our class. So we treated the event as practice and development. Only at Daytona can you stand on it and see what you can do.

Image
Barret training at Talladega. Knowing how the NASCAR chassis feels, he commented: "The Ghia likes Daytona, it's steady in the groove and the aerodynamics are right."

08Nov17; Wed. We make the 0800 driver's meeting, change from the Falken rain tires to the Hoosier Speedsters, 185/65x15's (TP 24/26), check the oil, and fuel up on street pump premium we brought ourselves.

Image

In our garages, we're alone in a sea of Porsches.

Barret goes out for his first practice just before noon, and on his second lap, the engine falters but Barret is able to drive back to the garage. He says it feels like ignition. We quickly discover two problems. The brand new Ignitor III ignition module in the brand new Pertronix distributor is too hot to touch; and there is a minor air leak in the metal fuel line coupling off the fuel cell that is affecting fuel pressure. Retightening the fitting fixes the fuel pressure, bumping it up from a low 1.5 and 2 psi to the proper Weber 3.5 psi. But we get no spark from the new Pertronix Flamethrower coil.

I install a new Pertronix Ignitor II in a spare 009, buy a yellow Accel ignition coil from a local auto parts house, install it, and the engine starts properly. With a quick 10° advance retime, we are ready to go again. Barret reports the Speedster tires are excellent, even with just a few minutes to test them on the infield, and says while the engine was running right, it was strong.

Image

We are armed with an aluminum-cased 9:1 cr, 74mm stroke counterweighted crank, 85.5mm hypereutectic AA pistons, chromoly Unitech I-beam connecting rods, ARP bolts, straight-cut cam gears, and a Bugpack 4063-10 Cam with 1.25 rockers. Carbs are 40 IDF's with 36mm vents, and 160 mains, 190 airs and F11 emulsions. We turned almost 7000 RPM on the Road Atlanta back straight with this engine in the spring, just shy of 140mph.

Image

Good company. Just ahead of the Ghia is a V8 Sunbeam Tiger (inspiration for Shelby's Cobra), and a 914-6, and just behind, a 427 Cobra. We're not here to try and beat these cars with our 1.7 engine. We're here to push our limits farther.

Barret goes out for his second practice in midafternoon, GoPro recording. He notices that even on the banks, the Ghia will not exceed 6400 RPM, very similar to what we experienced at Road Atlanta at the 2017 Mitty. We have 36mm vents in the Weber 40's, and that might be the top-end limiter. The carbs are jetted the same as at the Mitty.

160 mains, 190 Air, .55 Idle, F11 Emulsion

The Speedster tires are proving themselves formidable. Barret is able to whiz through the infield Horseshoe in third gear on three wheels, the inside front tire dramatically inches off the ground. The Ghia follows the line, no classic tail-out sliding.

I had an excellent view of this from my spot at the fence looking into the infield. Jim Allen, our RetroRacing photographer, was positioned perfectly to catch it all on camera.

Then Barret stopped coming around.

From my position, all I could see was the flashing emergency vehicle lights across the track near the Bus Stop (a prime spot for spins and crashes) and the corner workers waving black and red flags.

Image
Above: Daytona Track map, locating both the Bus Stop and Horseshoe turn.

I had no idea what happened, and a distorted, echoing loudspeaker announcement didn't help, as the announcer said the race would resume as soon as cars 53 (us) and 48, a Mustang, "were cleared off the track."

This was one of those agonizing moments in racing where you don't know what has happened but it all points to bad. The first rule of racing is if you put it on the track, you have to be ready to lose it. That means car or driver.

It seemed like a very long time before the first tow truck appeared pulling in a blue '65 Mustang, seemingly with no body damage, and right behind it was the silver Ghia, riding atop a flat bed, also visibly unharmed.

In-Car Video
https://www.youtube.com/watch?v=Z5I436HEV9c&t=59s

What had happened was while on the banking going flat out, Barret felt a loss of power. The engine made broken parts noises, and the cabin filled for an instant with wispy white smoke.

Barret steered the Ghia to the side of the track and the yellow oil warning light came on only as the engine quit.

At almost exactly the same time, Mustang 48 had stormed into the bus stop, a chicane at the far end of the back straight, and spun and stalled in some way as to block traffic.

Once we got the Ghia into the garage and the engine lid off, we saw the hole in the top of our aluminum race-case. The Ghia had lost no oil on the track. The moment of smoke had came from crankcase pressure escaping. The failure seems to be from a broken connecting rod on cylinder #2. And the rod appears to have broken from pure stress, not an unoiled bearing, as there had been no oil pressure issues displayed on the gauge or warning light.

Without a spare engine, our race was quickly over on Day One. Qualifying wouldn't even start until tomorrow. All heroic ideas to get a spare engine here (one setting in our shop ten hours drive away) were cooled by reality. And we didn't even have a MG or Triumph to race against. To keep team spirits up, since we had a rented beach house for a week, we stayed on the barrier island and went to Margaritaville for the next few days.

LESSONS LEARNED

We really needed Weber 44's, which even with 36mm venturis (same as the 40's) would probably have given us that little more top end breathing to peg 7000 and hold it in 4th. We did bring 38mm vents, but never got to test them.

The Speedster tires are fantastic. With the exception of Avon racing radials, the Speedster's are the first true racing tires we're used on the Ghia. All of our other tires have been high performance street tires. An important difference between the Speedster's and all our other tires (including the Avons), is the Speedster tires want to track where you steer, and graceful, tail-out slides are not on the menu.

Our new nose-mounted oil cooler is excellent. Oil temps, even in the 80° F. plus central Florida weather, stayed at the 220° F. level. A nose-mounted oil cooler is a very vulnerable spot, but most of the Porsche RSR's there with us had the same arrangement.

Image
Above: Daytona is not new to RetroRacing, having run our Blitzwagen there a couple of times before. Bounty hunters and process servers, take note: Left Dr Steve (aka Slick) standing, Hawkeye kneeling. Right Jamrod kneeling, Barret standing behind him, and behind Barret, David Scott.

FJC

UKLuke72
Posts: 152
Joined: Fri Nov 25, 2011 8:28 pm

Re: Flat Out At Daytona in a Karmann Ghia

Post by UKLuke72 » Fri Nov 24, 2017 5:07 pm

Love reading these FJC, keep the updates :)

Hypereutectics holding up well then... Ever had any reason to use forged pistons instead? Are they the Chinese IDF copies or the real deal? How did the Chinese ones fair?

User avatar
FJCamper
Moderator
Posts: 2690
Joined: Wed Nov 14, 2007 5:19 pm
Location: Birmingham AL

Re: Flat Out At Daytona in a Karmann Ghia

Post by FJCamper » Fri Nov 24, 2017 6:02 pm

Hi Luke,

We have used them all, forged Wiseco, semi-forged (Mahle), and the hypereutectics AA brand. We balance our own pistons and rods, and the hypereutectic piston is heavier than its true-forged counterpart. The hypereutectic material is certainly holding up for us in 85.5mm and 94mm pistons, but I hear the 94's should be rev-limited to 6500 rpm.

If you've followed the market, you know forged 85.5mm pistons are rare and getting more rare. The Mahles are apparently "semi-forged" (which explains their medium price range) and are lighter than the AA's.

I'd recommend 85.5mm AA's to anybody for high-performance street use and to most racers for 7000 rpm.

FJC

User avatar
Jadewombat
Posts: 1245
Joined: Sat Jun 22, 2002 2:01 am
Location: Houston, TX

Re: Flat Out At Daytona in a Karmann Ghia

Post by Jadewombat » Sun Nov 26, 2017 8:47 pm

These guys said widening the track helps with the understeer.

https://www.6speedonline.com/articles/g ... gn=content

User avatar
FJCamper
Moderator
Posts: 2690
Joined: Wed Nov 14, 2007 5:19 pm
Location: Birmingham AL

Re: Flat Out At Daytona in a Karmann Ghia

Post by FJCamper » Mon Nov 27, 2017 2:36 pm

Is the Jade Wombat anything like the Maltese Falcon?

We set up our road race Ghia (IRS rear end) for mild, steady-state understeer and no snap oversteer or snap anything. In a real high-speed sweeper, you want understeer and predictability.

This of course depends on tires, but we were lucky and all the high-performance street tires we used acted about the same. These "Speedster" tires are different in that they allow no drifting, sliding, or looseness. They just track where you steer, and that means at the limit they will either suddenly break away or slide. We haven't reached that point yet, but we tried in the Daytona infield, pedal to the metal in third gear through the horseshoe.

We now think we can go back to using a rear sway bar.

FJC

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: Flat Out At Daytona in a Karmann Ghia

Post by H2OSB » Mon Nov 27, 2017 2:58 pm

Mr Camper, did you guys remove the rear sway bar to limit the lifting of the inside front wheel? If not, was that a secondary concern? Did the wheel go higher than current with the rear sway bar?

H2OSB

User avatar
FJCamper
Moderator
Posts: 2690
Joined: Wed Nov 14, 2007 5:19 pm
Location: Birmingham AL

Re: Flat Out At Daytona in a Karmann Ghia

Post by FJCamper » Mon Nov 27, 2017 6:03 pm

Hi H2OSB,

A rear sway bar resists front wheel lift. No rear bar encourages lift.

A rear bar also encourages oversteer, which is why we stopped using one once we got seriously fast in sweepers.

Our driver got accustomed to good steady-state understeer, and we left it like that. But now with more power and sticker tires, we're trying to corner on three wheels and that is not good.

We've got to retest now with a rear bar again (all we have is a nonadjustable 19mm) to see how it affects overall handling.

FJC

Ol'fogasaurus
Posts: 13266
Joined: Tue Nov 14, 2006 1:17 am
Location: Just north of Seattle

Re: Flat Out At Daytona in a Karmann Ghia

Post by Ol'fogasaurus » Mon Nov 27, 2017 6:52 pm

FJ, since I am not doing the racing thing and too old to get interested in it again, I got a question.

I seem to remember hearing that some cars have some kind of after market bracketry that allows the sway bar to be lowered, either in the center pivots or at the ends of the sway bar reducing some of their activity in cornering; am I right? The VW system is a bit different but could something like this allow some sway bar use vs. no sway bar at all?

Then I was into it (a SCCA rule change stopped that) the sway bar was about the size of a 100 year old cedar tree front and rear :roll: .

Lee

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: Flat Out At Daytona in a Karmann Ghia

Post by H2OSB » Mon Nov 27, 2017 7:15 pm

FJCamper wrote:
Mon Nov 27, 2017 6:03 pm
A rear sway bar resists front wheel lift. No rear bar encourages lift.
FJC
It's so hard for me to keep it straight. All my autoX experience is from a fwd ('86 Gti). I had 25mm F/28mm R bars on that car and it lifted the inside R.

As I set up the suspension on my 1303 for autoX, I'm going to run a 22mm front bar and a 14mm rear bar from a Porsche 944....that was the plan, anyway. Would it be better to go 19mm F&R? I want the wheels as planted as possible and fairly neutral handling. But then, don't we all.

H2OSB

User avatar
Jadewombat
Posts: 1245
Joined: Sat Jun 22, 2002 2:01 am
Location: Houston, TX

Re: Flat Out At Daytona in a Karmann Ghia

Post by Jadewombat » Mon Nov 27, 2017 9:29 pm

Cool.

Not sure about the rules, but the technology and control systems have finally come around to where race teams are using hydraulics and a control unit to correct sway.

Ol'fogasaurus
Posts: 13266
Joined: Tue Nov 14, 2006 1:17 am
Location: Just north of Seattle

Re: Flat Out At Daytona in a Karmann Ghia

Post by Ol'fogasaurus » Mon Nov 27, 2017 10:04 pm

Jadewombat wrote:
Mon Nov 27, 2017 9:29 pm
Cool.

Not sure about the rules, but the technology and control systems have finally come around to where race teams are using hydraulics and a control unit to correct sway.
Is that anything like the hyd. bump stops?

User avatar
FJCamper
Moderator
Posts: 2690
Joined: Wed Nov 14, 2007 5:19 pm
Location: Birmingham AL

Re: Flat Out At Daytona in a Karmann Ghia

Post by FJCamper » Tue Nov 28, 2017 11:34 am

Hi H20SB,

Yes, a 28mm front bar and a 14mm rear bar would be a good start. SB understeer like crazy stock, and the rear bar tends to compensate for that. In our case, I believe our 19mm rear bar is too much. Even the 911S cars had less.

And Jade! Hydraulic suspension control goes way back in the Citroen's and today is an integral part of their current systems.

FJC

Ol'fogasaurus
Posts: 13266
Joined: Tue Nov 14, 2006 1:17 am
Location: Just north of Seattle

Re: Flat Out At Daytona in a Karmann Ghia

Post by Ol'fogasaurus » Tue Nov 28, 2017 11:57 am

https://www.mathworks.com/help/robust/g ... n_loc_drop

Is this what you are talking about?

https://en.wikipedia.org/wiki/Active_suspension

something new I'm trying to understand.

User avatar
Jadewombat
Posts: 1245
Joined: Sat Jun 22, 2002 2:01 am
Location: Houston, TX

Re: Flat Out At Daytona in a Karmann Ghia

Post by Jadewombat » Tue Nov 28, 2017 10:48 pm

I'm trying to understand it as well. One of my contacts on LinkedIn showed a cut-away of a new car they're building. I couldn't quite see the suspension setup so I asked him about it and that's what he said. They've ditched the sway bars in favor of a new system.

Your guess is as good as mine how the hydraulics work. I don't know if they're integrated into each coilover, etc.

User avatar
Jadewombat
Posts: 1245
Joined: Sat Jun 22, 2002 2:01 am
Location: Houston, TX

Re: Flat Out At Daytona in a Karmann Ghia

Post by Jadewombat » Tue Nov 28, 2017 10:51 pm

Just the thought of keeping all four wheels on the ghia under all turns near instantaneously without having to crawl under the car and change out parts for different courses, whoooo, that'd be sweet.

Post Reply