WTH Spider Rear Racing Suspension!

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ST3Racer
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Re: WTH Spider Rear Racing Suspension!

Post by ST3Racer » Thu Aug 01, 2019 12:26 am

Csaba,
If there was a prize for this thread, it would go to you. The Tri-Link is the answer in a racing 124 Spider (Coupe too). No Panhard (track) Bar. A Tri-Link with the Panhard bar will give the same wonky movement and bind as the stock configuration with a Panhard bar. The short upper trailing arms are horrible for bind! Go thru a set of esses hard and then go for a ride off the track - horrible. A Tri-Link with the "Wishbone Locator" will not bind. A car with both the Panhard and Wishbone however, is like holding your pants up using a belt AND suspenders....

The exact configuration of this rear suspension is confidential (per Jim S. ;), but if anyone is really interested, please contact me.

I couldn't do this without you Csaba, and Autoricambi - Thanks for doing what you do! Now, if you could get some 131 gearbox rear mounts, that would be perfect. I haven't seen them in 8-10 years.
Bill McMahan
Parker, Colorado
'69 124 Spider 2L ex EP racer, ex Volumex NASA ST3 Racecar - retired
'69 rebodied with '79 backdated chassis as '72 DP 1.8L Vintage Racer
'74 124 Abarth Stradale Replica
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ST3Racer
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Re: WTH Spider Rear Racing Suspension!

Post by ST3Racer » Thu Aug 01, 2019 12:33 am

Slipcased - Ronald,
Your looks like a '75-'78 CS1. Nice car, get it going. The information you get here will help you get running right and keep it that way. I will post as time allows and have updates soon. The Vendors are key as well. Use the ones that specialize in the Classic FIAT 124.
Bill McMahan
Parker, Colorado
'69 124 Spider 2L ex EP racer, ex Volumex NASA ST3 Racecar - retired
'69 rebodied with '79 backdated chassis as '72 DP 1.8L Vintage Racer
'74 124 Abarth Stradale Replica
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friedman
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Re: WTH Spider Rear Racing Suspension!

Post by friedman » Thu Aug 01, 2019 9:12 am

Bill, I assumed as much, that your old racer was probably too tired to repurpose. I helped a friend remove a front fender from a spider and we were both exhausted from trying to remove it as it was welded to the body in many areas we had no clue about.
Carl in Virginia
75 spider
83 Bertone
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Re: WTH Spider Rear Racing Suspension!

Post by ST3Racer » Thu Aug 01, 2019 2:37 pm

Carl,
For the $500 I spent for the '79 chassis, which had been stripped by the P.O. for a race build that never really got started, it was money well spent, and an opportunity to revisit the original build in a fresh light and make multiple improvements from the original build. Stiffer, straighter, better. Plus, I didn't have to strip the car, which is a PITA! I got exactly what I needed to immediately start the build, and precious little crap to dispose of.

I don't even regret that this would now be a "Garage Sale" item at Aspen - I could get it now for half price! But, I would be 8 month further behind on the build....
Bill McMahan
Parker, Colorado
'69 124 Spider 2L ex EP racer, ex Volumex NASA ST3 Racecar - retired
'69 rebodied with '79 backdated chassis as '72 DP 1.8L Vintage Racer
'74 124 Abarth Stradale Replica
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cgranju
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Re: WTH Spider Rear Racing Suspension!

Post by cgranju » Fri Aug 02, 2019 11:06 am

I would venture a guess many of us who may not have a lot at the moment to add are still quite interested in this & other racing threads. With the proper filtering for practicality, what you guys who race the cars figure out & do is good information to make many of these cars more fun to drive. So for that, thanks! (I guess I need to send an email about how this rig is applied to the rear)
Chris Granju
sunny East TN
owner of a number of Fiats built prior to 1986
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friedman
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Re: WTH Spider Rear Racing Suspension!

Post by friedman » Sat Aug 03, 2019 8:23 am

I find it amusing that "production" racers are allowed such a radical change in rear suspension configuration, no wonder it costs a fortune to go racing.

I recall a few years ago threads about doubling up the rear large trailing arms to act as an alternative to a rear sway bar, I guess taking advantage of the binding effect. This was for street 124s, I don't think anyone was doing it for race cars.
Carl in Virginia
75 spider
83 Bertone
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Re: WTH Spider Rear Racing Suspension!

Post by ST3Racer » Sat Aug 03, 2019 4:48 pm

Chris,
PM me and I will send some pictures of the install.

Carl,
There has always been a cost for "Production Racing", but it can reward those that can figure out what needs to be done to go faster, and clever or talented enough to make the needed stuff. The cost varies by how much skill that racer has, to make it themselves. Other wise, spend a LOT more to have someone else think it up and make it for you. It never stops. Humans are clever creatures... Just remember the three rules of racing: There's not enough time. There's not enough money. Nothing fits.

Time is the most important. The substitute for money it to think it up and make it yourself. Oh, and MAKE it fit...

Go to YouTube and look up the 2015 SCCA Runoffs at Daytona. Watch Gary Baucom in his FP 124 Spider 1756 in the F Production race. Start at about the 9 minute mark, and you will see: First, a properly built and tuned full-race 1756cc FIAT Twin Cam engine can be a rocket. Second, it takes the very best rear suspension geometry to go fast enough. Third, Miata drivers are reckless, and don't mind having to do bodywork, or have to have anyone else do bodywork. Fourth, time never stands still in racecar preparation, which is why I'm going to Vintage, where time still doesn't stand still, but advances in prep aren't so hectic.
Bill McMahan
Parker, Colorado
'69 124 Spider 2L ex EP racer, ex Volumex NASA ST3 Racecar - retired
'69 rebodied with '79 backdated chassis as '72 DP 1.8L Vintage Racer
'74 124 Abarth Stradale Replica
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friedman
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Re: WTH Spider Rear Racing Suspension!

Post by friedman » Sun Aug 04, 2019 7:34 am

It will be interesting to see your feelings about vintage racing. I have been hearing that it's becoming just as cutthroat as "real" racing.
Carl in Virginia
75 spider
83 Bertone
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Re: WTH Spider Rear Racing Suspension!

Post by ST3Racer » Mon Aug 05, 2019 4:27 pm

Carl,
If Vintage Racing is becoming more competitive from a Driver's standpoint, and less about the Cars, then I would welcome that. I want to compete - pass for position, and win. I don't believe that Vintage is to the stage of becoming "cutthroat", but I guess I'll see firsthand. To better explain, it's not a matter of what Vintage Racing is becoming, but the overall changing state of what "Motorsport" is becoming.

When I began Roadracing, out of a strong desire to do so, the only practical option was to build, or borrow, a competition car. I borrowed one for my first SCCA Driver's school at Road America, courtesy of my brother Mark. A handshake before we left the track that weekend sealed the deal for me to purchase that '72 ITC FIAT 124 Spider 1608, which I raced for more than 12 years and more than 60 races in SCCA. There were no other practical options in 1985 to get on an SCCA sanctioned track. There was no such thing as "track days". At ANY track, period. The concept hadn't been invented. One had to be committed (crazy?) to move forward from Autocross, which is what I did. At the time, there were only about 2000 to 2500 individuals world wide who could consider themselves "Racing Drivers". True fact, look it up.

Starting maybe about 15-18 years ago, "Country Club" track started to be built, and they supplemented their costs by allowing non-members to use their tracks for limited times, and only in logbooked competition cars. The business model worked, and now even inexperienced drivers with or without credentials can drive either competition cars, or personal vehicles, at speed, at what seems to be a majority of tracks nationwide, and abroad. Case in point - I have taken my street Abarth Stradale replica to track days, and HPDE days....

That has given birth to "Track Day Machines" like the Ariel Atom, and the tiny Lotuses, and other cars, and "Time Trial" events, and so on and on. A veritable explosion of cars on track on any given day these days. This has effectively culled the motorsports herd into two, (more?) groups. Door-handle-to-door-handle racing, and "NO-Touch" variants for those who won't or can't take the risks involved in all-out (cutthroat?) racing. Don't get me wrong, I believe that this trend is a good thing, but don't confuse the Time Trialer, or Drifters, or other groups as being either racing drivers, or their machines to be racecars.

Off the soapbox, back to the shop. I have a racecar to build.
Bill McMahan
Parker, Colorado
'69 124 Spider 2L ex EP racer, ex Volumex NASA ST3 Racecar - retired
'69 rebodied with '79 backdated chassis as '72 DP 1.8L Vintage Racer
'74 124 Abarth Stradale Replica
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davedecker4
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Re: WTH Spider Rear Racing Suspension!

Post by davedecker4 » Mon Aug 05, 2019 6:29 pm

Bill,

Great explanation as well as history lesson. Thank you!
Any thoughts on racing the 1608cc engine versus the later 1.8 and 2L? Just wondering if its all power and torque, or did you find significant differences in engine characteristics. Also when did you make the switch?
Dave Decker
a 'couple' Fiats and Lancia's
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