STS Suspension setup questions

[benjpi]

So, I've got an AWR rear bar on the way, the big one. Plus, I've also just received my very own MP3 front bar. Seems I've got my winter projects all cut out for me.

Once again, my cheap gene is kicking in and I'm back to the 205/50-15's. I'm a NASA member, and the Konig Feather wheels are calling me, with that nice membership discount. If I'm going to eat a set of tires a year, I can't really afford much more.

I've got a decent deal, perhaps, on a set of 336# 8" springs, I'm considering them for the back. It seems all you hardcore FS folks have run higher rates in the back, do you think that would be a good idea? The stock GC coilovers ARE 250 in the back (xeldrex is right, of course).

Someone here posted a link to Grassroots Motorsports where they put a motorcycle battery in a miata for the weight savings. As luck would have it, I've a few of those laying around! Maybe that will be another part of the winter work.

And just to add further to my obvious illness, I've got my hands on a TIG welder. A few tubes from here & there, and custom header? Hmmm, right after I learn to WELD, I suppose...

In general, it seems the Philly region is a tough place to break into the STS game, there are MANY well prepared cars & drivers that go to the events. Just the same, tuning the car AND the driver is half the fun.

 

[dmitrik4]

the flip side to the tough competition, of course, is that your improvement will come much quicker, and there are plenty of talented drivers around to help you along.

 

[aMaff]

hmmmm... how light are said motorcycle batteries? (naughty)

 

[Auto-Xer]

hmmmm... how light are said motorcycle batteries? (naughty)

As I recall, the Hawker Genesis is about 10-11 pounds...there are others as well, some in the 7-8 pound range.

http://sccaforums.com/forums/thread/183189.aspx

 

[xelderx]

I ran an Auto Zone lawnmower battery in mine. Lasted 2 years and is still going strong.

 

[benjpi]

I'm with xelderx on this one: buy a cheap battery, and as long as it can turn the starter you should be fine. I use a YTX9 in the bike (11.5:1 twin, has a 1.4kW starter) and it will crank that for 30-40 seconds or so (its carbed, sometimes it doesn't cooperate). I was planning on trying the same YTX9-ish battery in the car. The battery weighs 9 lbs, and costs about $60. For my car, that would be about a 30 lb weight loss!

 

[aMaff]

that's a great idea justin. I'm in the same boat (as is pretty much anyone with a car...). Those batteries weigh a ton! Justin: do you have a part number or any other specifics on which to buy? Or is there only 1 "autozone lawnmower battery"? lol

 

[xelderx]

Justin: do you have a part number or any other specifics on which to buy? Or is there only 1 "autozone lawnmower battery"? lol

Mine cost around $25-$30. I think it had 300-330 CCAs. They had 3 different versions, but the only main difference was the CCAs. Get at least a 300 CCA one.

 

[aMaff]

Mine cost around $25-$30. I think it had 300-330 CCAs. They had 3 different versions, but the only main difference was the CCAs. Get at least a 300 CCA one.

much obliged sir, thanks
(rei)

 

[dmitrik4]

maff, i don't think there is much weight to be saved on the miata w/ a lighter battery...our batteries are already pretty small. hollis' build thread on GRM had a post on this.

 

[aMaff]

there's not a lot of weight to be saved in general, but every little bit helps... lose an ounce from 16 places and you've lost a pound

 

[apexlater]

Yeah, but getting the car as light as possible is not what you should be trying to do.

The right rear of the Miata is the lightest corner, so from a corner-weight standpoint you want to try to "move" weight to that corner. Granted, there are no minimum weight requirements in STS2.....so nevermind.

 

[aMaff]

Yeah, but getting the car as light as possible is not what you should be trying to do.

Crap, you mean I shouldn't be on the lookout for a manual steering rack!? I've wasted too much time on F/S / classifieds ads on forums (sad2)

The right rear of the Miata is the lightest corner, so from a corner-weight standpoint you want to try to "move" weight to that corner. Granted, there are no minimum weight requirements in STS2.....so nevermind.

I figure that taking the weight of the A/C and (eventually) power steering out of the front of the car can offset taking weight out of the diagonally opposite corner w/ the battery Ghetto corner weighting y0!

 

[apexlater]

Crap, you mean I shouldn't be on the lookout for a manual steering rack!? I've wasted too much time on F/S / classifieds ads on forums (sad2)

No, I think that a manual steering rack would help your car out alot.

Don't get me wrong. I don't think there is anything wrong with trying to get your car fully prepped, but unless you are willing to get a "built" motor, alot of things that can be done won't make a whole lot of difference getting your times down.

You would notice a different steering rack, I doubt you would notice a lighter battery.

That's all I'm sayin'.......yo.

 

[aMaff]

Oh I completely agree. I know for a fact that my car is far from fully prepped. But if I can get it as good as I can with the engine being the only limiting factor. Then... I'll drop a BP in and move to CSP

(maybe )

 

[benjpi]

Well, that was fun. My AWR rear swaybar was used. Well used. Really, really well used. By someone who worked in an acid factory where the roads were paved with salt.

So..... The bar arrived (as purchased) without the black aluminum standoff brackets from AWR. They are $25 each from AWR. Okay, so not to bad, used bar still a good deal. BUT, AWR had $50 for shipping & handling on their website. I had a hard time swallowing that: $50 in shipping for two 4-oz aluminum chunks that would fit in an envelope. So, no purchase. I decided to make them myself.

I looked at a few pictures, got the idea, and measured up a few stock items. Made myself a CAD drawing, and got ready to fabricate.

I got a chunk of 7/8" thick 6061 Aluminum scrap from work, and set to work. I did my "roughing" with a sawzall, and did my finishing work with a large selection of coarse-tooth files & rasps. From 5' away, they look just like the AWR parts.

On to challenge number two: The adjustable clamp brackets that hold onto the bar were seized solid. I tried tapping on the bolts, heat, liquid wrench, and so on. No dice, the bolts wouldn't budge. I bent the socket wrench trying to get them loose. Instead I cut through the two outside clamp bolts (and the clamp) along the split line of the clamp. That got the clamp / end link assemblies loose enough that I could get them off the bar.

Then I drilled & tapped one new hole between the two outside clamp bolt holes, 1/4"-20 fit just fine. Slid it back over the bar, but it won't go around the bend in the bar with just a single clamp bolt. This time I used a HEX head bolt, rather than a socket head bolt. When / if they seize up, you can put more leverage on a hex head than a socket head.

The adjustable tie rods are in rough shape too. Tomorrow I'll have to disassemble / wire brush / antisieze / reassemble them. Maybe, just maybe, I'll get it on the car.

Question to anyone with the AWR bar: can you run it with the adjuster INSIDE the curve?

 

[xelderx]

Question to anyone with the AWR bar: can you run it with the adjuster INSIDE the curve?

Yes you can, but I broke the mounting tab on one of my struts twice doing it that way. They were the J-spec Mazdaspeed adjustable struts at the time. Eventually I just got stiffer springs and backed the bar down.

 

[aMaff]

random question since you have experience with both: do the AWRs have stronger sway bar mounting tabs than the rest of the struts out there for the 3rd gen proteges?

 

[xelderx]

Not citing an engineering degree...they are stronger than any of the stock mounts. I haven't taken a good look at mine side by side with anything else in a long time, but I'm pretty sure the AWR mounts are thicker gauge metal.

 

[benjpi]

Thanks for the info, not so keen on broken brackets so I'll keep it just outside the curve for now.

Engineering degree or not, not broke is not broke. Usually, that means stronger....(although we'd of course need to run a double blind placebo trial with SPC & data acquisition fed through a Cray to really confirm that...)

Considering what you've done with a P5, I figure if it worked for you then its prolly ok.