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Lightening for racing
Posted by: BobV66Vair ()
Date: December 22, 2017 07:08AM

I am getting ready to do all the metal work on my race car to be. A 66 that has a 140 engine. I am looking seriously at removing metal from the unibody in a number of places. I am thinking of round holes, ala aircraft metal lightening. I can see a number of places that can happen. Anyone done this and in which locations? I think I saw the Sunoco race car done with holes/dimples in the upper door steel but I don't recall seeing much else.

Anyone done some major lightening on the horse collar? Replaced it with something better/lighter?

I do need to stay within the FIA Homologation for the Yenko stinger but we have come a long way since then!

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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Re: Lightening for racing
Date: December 22, 2017 07:32AM

I don't have a photo of it, but I made an aluminum cross member to replace the horse collar. It was made of square tubing with end plates that pivoted on the Corvair chassis. The rear sway bar was also mounted on this cross member. The drive train was hard mounted to the cross member, and because the cross member pivoted on the chassis, I could unbolt the solid rear motor mount and remove the drivetrain as a unit by swinging it down.

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Re: Lightening for racing
Date: December 22, 2017 07:35AM

I should add that once I went to a vertical fan assembly, I could no longer just pivot the drive train down to remove it; but the aluminum cross member still made it easier to remove the drive train.

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Re: Lightening for racing
Posted by: Jim Stukenborg ()
Date: December 22, 2017 08:21AM

Bob, here is a copy of the methods that Jim Schardt used to get his Stinger ready for SCCA racing in 1973 and 74. This is just the weight reduction page. There are 13 more pages to the complete preparation process. Jim

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Re: Lightening for racing
Posted by: 19sixty5 ()
Date: December 22, 2017 04:51PM

The general "rule" in drag racing is every 100 lbs removed the car is a tenth of a second faster...

65 Crown Hardtop

Huntsville, AL

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Re: Lightening for racing
Posted by: Mike Stillwell ()
Date: December 22, 2017 04:58PM

If you read Schardt's list, He doesn't talk about cutting up the body. Brakke's car is not hacked apart. It still has full front inner fenders. You start losing a lot of rigidity for a few pounds of weight pretty quickly.

Mike
YS-117

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Re: Lightening for racing
Posted by: yenkomark ()
Date: December 22, 2017 07:05PM

We had to add 35 lbs of ballast to YS 037 at the Brickyard Vintage event to make legal weight

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Re: Lightening for racing
Posted by: American Mel ()
Date: December 22, 2017 07:35PM

But, the beauty of adding "ballast" is that YOU get to decide just WHERE that add weight goes!thumbs up

.
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
'66 Monza Coupe - 4spd, 140 Daily driver beater
'67 Monza Vert. - PG, 140 Daily driver beater
'67 A/C Moredoor Monza - 140 4-spd. driver

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Re: Lightening for racing
Posted by: yenkomark ()
Date: December 22, 2017 08:45PM

Quite right ! Worked out well...lowered the Stinger lap record by .5

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Re: Lightening for racing
Posted by: v8vair ()
Date: December 23, 2017 04:19AM

Ive done no cutting on the 64 Racer and very little on the V8 except for cooling and i skinned the doors and lids.Unless your roll cage is tied onto the A and B pillars (most cages miss that by mile) or your rules allow you to run tubing all the way to the back and front keep that unibody in tact.
The Front bumper on a Late Model(and maybe an early) is a major structural component of the front end but seems to get tossed on alot of Racers. Without the front bumper,especially on a Crown, watch the front frame rails flex back and forth with wide sticky tires on a hot day as you steer it back and forth. We saw this as Kids on the McIntosh racer and ever Notice YS 005 always ran a front bumper and now YS 095 now has one? The same two cars Always got or get scaled and aligned before EVERY race.My V8 gets aligned every race and should be put on the scales more often as the Bondo and my fat ass keep growing. Plus you need to keep getting the car faster to offset OLD Age so your lap times dont fall off !!! And Yes 037 was flying at Indy with Michael and good Ole Drum Brakes !!!

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Re: Lightening for racing
Posted by: dryenko ()
Date: December 23, 2017 06:26AM

I would add that is you still have steel body panels, and make the rear panel removable for easy engine removal, the rear bumper can also add body stiffness, as Mike mentions regarding the front unibody stiffness.
It is also "some" protection if any "rubbing" occurs.
With all fiberglass panels, a different approach is needed, since attaching a bumper to flexing fiberglass is not productive.

Bob C aka Dryenko
Dobson, NC 27017

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Re: Lightening for racing
Posted by: isucorvair ()
Date: December 23, 2017 06:40AM

I want to say that bob D. Took 27 lbs of so out of the roof of the Flexi-Flyer.

Then....he cut the whole roof off and put another back on, too much.


Eric P
DeWitt, IA

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Re: Lightening for racing
Posted by: BobV66Vair ()
Date: December 23, 2017 10:59AM

Thanks for all the information. My current brain problem is that I plan to run in Conference racing (ICSCC) here in the Northwest and they seem to refer to the CCA rules on most things. I am confused about many of the items since the SCCA rules are a maze f cross references and differing rules only noted in classes. My goal is to run in E Production so many of the really extreme changes are not available. No replacing body panels, no roll cage other than for safety, glass must all stay, etc.

I think I need to talk to the people who run my conference and find out just what they allow to stay in my class. Up here, I may be the only car in E-pro! Easy way to win. grinning smiley

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

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