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Great pics of the tour. Looks like a ton of fun. Love the luggage rack (as well as the car in general).

Looks good. Where did you source the parts for that front swaybar?

Did you go with the zero offset Aeros? (I noticed they were not available with negative offsets) Can you tell that the increased scrub radius causes any ill effects?

_________________
He is a wise man who does not grieve for the things which he has not, but rejoices for those which he has.

Thanks for the comments.

The fronts are 4" BS 7" wide, so that makes...uh...1.5" more scrub radius than I have with the street wheels. I definitely did notice this, but mostly in the pits. On the track it didn't seem to matter at all. Hoosiers rock, BTW, they made me look like a decent driver.

The sway uses Speedway 5/8" poly rod ends and a bunch of odds and ends from McMaster-Carr, including 1/2" steel rod stock ("stressproof" alloy FWTW).

The basic idea is the poly rod ends mount to the ends of the wishbone pivot bolts using coupler nuts, and the outboard ends of the sway bar go thru regular rod ends mounted on the wishbones. I can get a better picture and a parts list, if interested. I think it'll only work with +2" hgt McSorleys, because of the space under the nose cone.

I also don't guarantee it's actually doing anything, 1/2" is pretty light

ok, i was bored, so I went ahead and compiled a sway bar parts list:

McMaster:

1 90977A210 2 Each Grade 5 Zinc-plated Steel Coupling Nut, 5/8"-18 Screw Size, 2-1/8" Length, 13/16" Width
2 94165A471 2 Packs 18-8 Ss Threaded Insert With Nylon Patch, 1/2"-20 Int Thread, 5/8"-18 Ext Thread, 19/32"l
3 6436K71 4 Each Two-piece Clamp-on Shaft Collar, Aluminum, 1/2" Bore, 1-1/8" Od, 13/32" Width
5 6628K28 1 Each 1144 Medium Carbon Steel Rod, 1/2" Diameter, 6’ Length

Speedway:

91008051-STR STAINLESS STEEL ROD ENDS 2 each
1750115 PRECISION ROD ENDS 2 each

Harbor Freight:

44094-0VGA rod bender

+ misc washers/bolts/nuts

Thanks!

_________________
He is a wise man who does not grieve for the things which he has not, but rejoices for those which he has.

I was wondering if you were sharing your Autocad files? I'm getting ready to start and would love to follow your example of layout on a full-size set of frame drawings. Thx.

[/quote]I was wondering if you were sharing your Autocad files?[/quote]

FWIW. Remember to check your printer scales, they will drift around a bit. I had to print out top and bottom in two halves, and the printer scaling (or paper feed) had drifted enough so there was about 1/8" mismatch in the long direction.

Thank you VERY much. This will help my frame build considerably. I'll check the printouts for errors - thank you for the tip.

Happy New Year

Back from the PacNor08, so that makes another couple thousand trouble-free miles. That makes roughly 6-7k total, don't know exactly, because the odo in my electronic dash thingy doesn't work right. Another minor annoyance is the Kirkey seat upholstery is completely shot already, so I guess I'm going to have to spend $100 on one of those every 5-6kmi.

I was going to rave about my RA1 tires and how treadlife is decent, the grip is amazing and they have less tramlining than most street tires, but since they recently discontinued production that would be pointless:(

Caution: Shaky camera, take Dramamine.

An upgrade!

The GTS arms have always bothered me. They do not give wide enough track with a 442, especially with my spiffy new 11.5" Caterham rear fenders. They are also somewhat unattractive due to the substantial gusseting I added after bending them. There is also not a whole lot of caster.

So over Christmas holiday I made new ones. If anybody wants specifics, just let me know.
Also, if anybody wants the old arms, LBJs, and coilovers, let me know!

BTW, once I've tested them out for a while, I WILL take things apart and have the arms plated. I'm partial to the yellow zinc.

Great looking set of arms! I like the camber adjustment being separate from everything else.

I'm sure a lot of people would like some specifics on them.

Seeing such a good view of them raises one niggling little thing that always worries me about some A arms. You have 2 pivot points on the top arm and while intellectually I know that most of the force goes thru the bottom arm, it just seems like it would allow for some movement under pressures. Is the really NO movement whatsoever on the upper arm?

_________________
mobilito ergo sum
I drive therefore I am

I can explain it to you,
but I can't understand it for you.

Good call. It did allow far too much movement unless the bolts were good and tight. So once I got the camber/caster roughly dialed in, I welded the rear bushings to the tabs.

OK, I'll post specifics as I retrieve them...

Uppers:

FK hjmx8t REs with miscellaneous spacers.
Legs are .75x.095 4130, directly tapped to 5/8-18, then McMaster 94165A471 screwed in to provide 1/2-20 threads. .875x.156 DOM for the outer bushes.

Outboard is 1.25x.188 DOM to fit the slick aluminum TRE adjusters I was using before. They are available from the UK, but I can't remember where. They use the Euro Ford Transit joint, RockAuto p/n QD1117RHT. The Miata spindles were previously retapered for this.

Lowers:

1.0x.095 4130 legs with the standard Locost urethane bushings in 1.375x.12 DOM

AFCO #921-20043 screw-in BJ cup

QA1 1210-505 & 9029-201 (Trick aluminum ball joint with 1" longer stud, which lowers the front an inch and gives some more camber gain. Otherwise it's similar to Moog K772) Taper matches stock Miata; length is a bit excessive so I had to use a small bushing under the BJ nut.

QA1 82 series coilovers, 6" stroke (!), of which I use about half. Custom 3/8 valving suggested and modified by Naake.com
4" bump/3.5" droop.
Caution: Due to the weird angled Miata spindle and the flat arm construction, the lower BJ maxes out it's angle at ~4.2" droop, which is not much margin and will decrease with more caster/camber. In future I may have to reduce C/O extension by putting in internal washers.

Arm length came out at 20.9", spring base of 17.8", leverage ratio on coilover at 2.1:1
(Important Note: I actually measured the leverage ratio by moving the suspension up and down and measuring the shock travel. It did not quite match the spreadsheet-calculated leverage ratio and had a significant effect on spring rate choice.)
Caster currently at about 8.5°. I think I have at least ±2° range of adjustment.