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Where to find odd wheel sizes and offsets

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Old Apr 2, 2019, 11:44 AM
  #31  
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Originally Posted by kaj
The pistons help that much? Bends around the ACD are okay for the ducts? I use SRF fluid. I was advised Ti shields keeps too much heat in the pad, but I guess that's better than the caliper; remedied by a different pad.
This is all good news because I actually like my setup and have quite a bit of $$$ tied up in it.
Yes, stainless conducts heat MUCH less than mild steel does.

Ducting works best with minimal deviations from straight. So if it curves around the acd stuff yea it'll still work, but not as well.

Ti shields definitely help. You want heat in the pads, if it doesn't stay in the pad it goes to the fluid. If you're overheating pads you absolutely should move to a more aggressive compound. If you're braking hard enough to warrant stainless pistons or ducting you should be running pretty aggressive pads.

More aggressive pads are safer on track. Pad fade is seriously dangerous, it doesn't come on like fluid fade. There's no advanced notice like you get with fluid fade. The brake pedal will not feel any different or squishy like fluid fade but the car will not stop, it's scary stuff.

I recenty saw this, it's a good read: https://www.essexparts.com/news-blog...d-owners-guide
Old Apr 2, 2019, 01:34 PM
  #32  
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The stock pistons are aluminum, not mild steel, so they transmit a lot of heat to the fluid.
Old Apr 2, 2019, 02:00 PM
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Even worse. Aluminum is a bit over 15 times more thermally conductive than stainless steel.
Old Apr 2, 2019, 02:24 PM
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Should make them out of wood, I hear that stuff is pretty isolating.
Old Apr 2, 2019, 02:33 PM
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Or burn the wood and make them out of the leftover carbon
Old Apr 2, 2019, 04:40 PM
  #36  
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Originally Posted by ayoustin
Yes, stainless conducts heat MUCH less than mild steel does.

Ducting works best with minimal deviations from straight. So if it curves around the acd stuff yea it'll still work, but not as well.

Ti shields definitely help. You want heat in the pads, if it doesn't stay in the pad it goes to the fluid. If you're overheating pads you absolutely should move to a more aggressive compound. If you're braking hard enough to warrant stainless pistons or ducting you should be running pretty aggressive pads.

More aggressive pads are safer on track. Pad fade is seriously dangerous, it doesn't come on like fluid fade. There's no advanced notice like you get with fluid fade. The brake pedal will not feel any different or squishy like fluid fade but the car will not stop, it's scary stuff.

I recenty saw this, it's a good read: https://www.essexparts.com/news-blog...d-owners-guide
I'm not quite that noob I wouldn't run insufficient pads. I like to live dangerously...to a point LOL
I've had pads overheat on a mountain drive. It was less than fun LOL
Nice article!

Originally Posted by Dallas J
Should make them out of wood, I hear that stuff is pretty isolating.
Done. Stay tuned...
Old Apr 3, 2019, 09:31 AM
  #37  
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Originally Posted by ayoustin
The 10.5 number is the distance between the bead sealing surfaces. The actual width of the rim itself is a bit over 11". 315 can fit without looking absolutely obnoxious but the actualy benefit of going that wide on a 10.5 is debatable.

Haha and if you want to brag, lots of manufacturers list section width at 300mm for their 295s.
we went from a 285 a7 to 315 a7 both on a 10.5" rim and it was a noticeable improvement in corner grip. You can tell a difference in the weight and effective gearing but i think its a benefit overall on most courses with the 315.
Old Apr 3, 2019, 10:48 AM
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Originally Posted by Meathooker
we went from a 285 a7 to 315 a7 both on a 10.5" rim and it was a noticeable improvement in corner grip. You can tell a difference in the weight and effective gearing but i think its a benefit overall on most courses with the 315.
Interesting, thanks for sharing! To date I only know of you and Andy S that have run 315 hohos on 10.5" wheels.
Old Apr 8, 2019, 08:53 AM
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Originally Posted by Meathooker
we went from a 285 a7 to 315 a7 both on a 10.5" rim and it was a noticeable improvement in corner grip. You can tell a difference in the weight and effective gearing but i think its a benefit overall on most courses with the 315.
Any recent pics? I'll post up later but I placed 2nd both days this weekend at Roebling which is HELL on tires. My idea for 275 R1S's seems to be...up in smoke lol. Amb temp was only about 80, and I lost the tires on lap ~5.....of 27. The vid will show they did great, but ya, need more tire lol. The leader was on 315's. The obvious downside is the straights, which the south has lots of. I was neck and neck there so loosing that much hp (and drag due to lager tire) isn't ideal either. Sigh. The 25/64 Mich's are looking mighty good haha.

Last edited by Balrok; Apr 8, 2019 at 08:59 AM.
Old Apr 8, 2019, 11:14 AM
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Would an R1 not help much vs the R1s?
Old Apr 8, 2019, 01:08 PM
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It would, but it's a give and take like an R7 vs A7. Most of em are running A compounds because the initial green flag is "it" on a narrow course like Roebling and the normal R1's take a couple laps to come in and are on average 1-2 seconds slower. The only real place to pace there is the straight if you don't have more grip then the M3 guys on 315's. Enough strategy to make your head hurt lol.
Old Apr 8, 2019, 05:40 PM
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Yeah... kinda makes it not sound fun any more That's when I'm out
Old Apr 8, 2019, 05:53 PM
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Originally Posted by Balrok
Any recent pics? I'll post up later but I placed 2nd both days this weekend at Roebling which is HELL on tires. My idea for 275 R1S's seems to be...up in smoke lol. Amb temp was only about 80, and I lost the tires on lap ~5.....of 27. The vid will show they did great, but ya, need more tire lol. The leader was on 315's. The obvious downside is the straights, which the south has lots of. I was neck and neck there so loosing that much hp (and drag due to lager tire) isn't ideal either. Sigh. The 25/64 Mich's are looking mighty good haha.
Ronnie @ RS Motors posted a photo of the Falken 315s on a 10.5" wheel:
View this post on Instagram

Doesn't look like an easy fit, but they made it work. That front fender and side skirt are spaced out farther than I expected.
Old Apr 8, 2019, 06:10 PM
  #44  
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That 315 looks really narrow.
Old Apr 8, 2019, 06:18 PM
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Ive beat around under the rear of the Evo now enough to get a good feel for what would be needed to fit the 315s and its not a simple path. Trailing arms, relocate/modify fuel filler, cut and message front area on inner fender well, make sure spring perch is above tire or custom control arm (I may be making one of these for myself). Then you can get the +38 offset to fit without any spacers. Now, you still have to pull the outside probably on the order of an inch from factory and run enough camber to get the top to tuck.

Not impossible, but at the end of the day you'll compromise stuff getting there. You wont be able to run as low as you could doing it the right way and you'll probably still have locations you rub.

I know cutting is painful and hard to reverse, so I would highly recommend stopping at 295s with un-cut fenders.



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