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wheel/tire choice for FC track car

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Old 01-23-17, 02:11 PM
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I don't have a problem with the slots, the bolt heads hit the side of the sheet metal of the strut tower and still not enough camber
Old 01-23-17, 08:48 PM
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Originally Posted by Lavitzlegend
I don't have a problem with the slots, the bolt heads hit the side of the sheet metal of the strut tower and still not enough camber
How close are you? If you have S4 lower arms loosen your ball joints from the arm, pull outward and retighten them.
Old 01-25-17, 09:56 AM
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That's an interesting idea I might have to try. I was considering even buying extended ball joints but putting a custom made wear part on my car is not very appealing... It's already hard enough to get simple wear parts locally for these things. The camber plate bolts are as far inward as they can be right now (touching the circle on the shock tower). I have seen some people remove one of the bolts since really it is only 1 that is hitting but I would rather leave them all in tact.

Ideally I would like to get around -2.5 deg in front but it would be nice to get more than that so I can tilt the wheel away from the coilover a bit to get back to 2.5 and gain some clearance there.

Last edited by Lavitzlegend; 01-25-17 at 09:59 AM.
Old 01-25-17, 10:22 AM
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Oh, the camber plate bolts hitting the body first?
I thought you meant the big nut on the end of the shock shaft hitting the body- that is your limit.

Yeah, most top hats have a row of holes for the bolts so you move the bolts to other boles to get more movement.

This wasn't quite enough on my Stance so I used button head hex head bolts so the rounded edge of the bolt head was under the flared lip of the hole in the body.
Old 01-25-17, 11:12 AM
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I'll have to look at it in more detail when I get home tonight. Haven't had the Pettit coilovers on the car for very long but was just having trouble getting enough camber when I tried to set my alignment specs
Old 01-25-17, 05:44 PM
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Is there is meat on the strut top/spring perch you could drill and tap new holes to get more movement.
Old 01-26-17, 10:01 AM
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I would be more inclined to cut slots in the shock tower before going that route. I have a Mazdatrix 3-point strut bar anyway so there is plenty of support up there. Didn't get a look at the coilovers yesterday to see if there were any additional holes to move the lock screws to. Even when the car is in my attached garage it's hard to get motivated to do anything in the garage when it's cold out lol
Old 01-26-17, 10:32 AM
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Just as long as you realize how modifying the unibody may affect classing if you decide you want to race later.
Old 01-31-17, 06:10 PM
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What J9FD3s and rocklobster said
Buy the smallest diameter wheel to fit the brakes.
Race rubber is cheapest in the 15" or 16" diameter trim. I have 4 starspecs for under 550.
I have seen people match the straight way end speeds based on your gearing if you are running NA. You want 15 20 mph left over in the tallest gear...
I feel like tire width is function of your hp/weight as that determines how much traction you need. Putting super wide tires and having 100 hp or ultra light Miata doesn't really help!
Old 01-31-17, 07:12 PM
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Originally Posted by roadtripRX7
Putting super wide tires and having 100 hp or ultra light Miata doesn't really help!
BUT IT LOOKS COOL #RACECAR
Old 01-31-17, 09:26 PM
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275s all around are barely enough on my car. I have to run 17s at a minimum
because I needed bigger brakes.
Old 02-01-17, 12:17 PM
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Quote:
Originally Posted by roadtripRX7 View Post
Putting super wide tires and having 100 hp or ultra light Miata doesn't really help!


Doesn't help if you are behind slow cars in the corners...

There are plenty of 100hp Miatas and Hondas on 275/35-15 tires on 15x10 wheels proving you wrong on the track.

I personally race a 108rwhp RX-8 on 295/30-18 DOT-Rs on 18x11 wheels (from my FD) - though not on a "real track".
You just learn to not slow down for the corners and when you do have to drop your speed so low for a corner that you aren't up to the limit of cornering (kinda feels like you momentarily stopped racing...) you just work on your line and back-siding that apex to set you up for the upcoming corners.

I understand it might be a different story if you are on a track like the the old LeSarthe with the 3 mile long Mulsanne straight...

But my point is don't worry about over tiring a car till you have actually done it and know what that limit is. If there is any corner on the course where you are up to the limit of traction, you might be faster with more grip.

If there isn't any corner on the course where you are up to the limit of traction... well I don't know, why are you out there?
Old 02-02-17, 10:57 AM
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BLUE_TII
I agree with what you are saying. It is a balancing act. A larger diameter/ wider isn't the best solution. I have seen tiny Honda Civic and Geo metro on super fat tires well made suspension handle like they are on rails. Its fun to watch how fast they can go in the corner!
Everything has to work with each other, if the suspension is taller like on a street/track setup, I am not sure a wide tire would help as much. Also consider the rain aspect if its a not trailer-ed car.
The track layout definitely plays an important role.
Old 02-02-17, 11:20 PM
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Originally Posted by roadtripRX7
What J9FD3s and rocklobster said
Rocklobster beat us at the nationals, he knows what he's talking about.

actually in PTE, his FC and our miata were on the same tires, 205-45-15 Hoosiers. it was an interesting race, because the miata was 134hp/2380lbs, and he dynoed high (our dyno, is infamous, its more like a random number generator) so he was like 170hp/2900lbs.

in the qualifying sessions, he had an easy pole, he could pull like 6 car lengths on the straight.

the race was different though, it was 40 minutes, so suddenly the 2900lbs was the thing. 40 minutes at race pace in a 2900lbs car is a lot to ask from 205s!

we broke a wheel stud, and had a few more come loose, so its a good thing we had extended studs, and he easily won.

highlight reel https://www.youtube.com/watch?v=xQI9Q_6AQ04
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