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Woods247 BrokeFiST Build

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I am surprised you have issues with your Falkens. I haven't had any issue with two sets of mine.
I'm also on 2 sets now with no issues, and many friends also with no issues. I have seen multiple posts about delaminating, but I've seen lots of people either get new tires or some sort of resolution. I'm really curious how Gridlife is going to continue with Falken. I believe they have 2 or 3 classes where the RT660 is the spec tire. It'll be interesting to see if that changes for next year.
 


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Woods247

Woods247

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Is the ST200 clutch different from regular? AP Racing makes our clutches too.
The st200 clutch is an AP Racing clutch. Supposedly it can handle more power than the stock one but I don’t particularly trust anyone’s opinion in this industry. 😂 I just went with my gut and decided to “upgrade”. My intentions of adding more power to this car have been tabled until I achieve maximum grip and the aero is also maximized. I have no need for power if I can’t put it down but when I do build the next engine I’d like to use the trans I’m buying now.

The Gripper LSD should resolve wheelspin with minimal additional maintenance. I don’t know of anyone using it in the US but I’m sure it’ll be superior to the MFactory. I spoke by phone with Tony at Pumaspeed and we discussed their race cars and time trial setups. They use the clutch style diff exclusively and now I understand why.

I went with the ST200 AP Racing clutch and OEM flywheel for reliability. After we lower my splitter, build splitter tunnels and add a flat floor the aero should be significantly improved. I figure the new diff will shave 2-3 seconds per lap at Road Atlanta with the existing aero. I should be at least 5 seconds faster with completed aero and 100TW tires.

Financially, I’m being more reserved with my car budget. I don’t suspect I’ll have the aero resolved until late 2024 or 2025 unless someone fascinated by my goals wants to help out. The good thing is, I have hundreds of hours of seat time in this car so I can definitely recognize the smallest change. The Gripper will probably be the best upgrade to date and I hope to get longer life out of the ST200 clutch. The OEM has been fantastic so OEM+ should be just as good and maybe last several more years. I still love this car and have no desire to ever sell it so I wanted to build the new transmission with that in mind. Well, that and hauling ass through corners.
 


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Woods247

Woods247

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I'm also on 2 sets now with no issues, and many friends also with no issues. I have seen multiple posts about delaminating, but I've seen lots of people either get new tires or some sort of resolution. I'm really curious how Gridlife is going to continue with Falken. I believe they have 2 or 3 classes where the RT660 is the spec tire. It'll be interesting to see if that changes for next year.
I’ve had more RT660s than I care to count and never had a problem until this year. Eight tires (all heat cycled) cracked all the way across the tread. Some even delaminated. My buddy’s Golf R absolutely ate them at GTA and GL this year.
 


Dialcaliper

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Is the ST200 clutch different from regular? AP Racing makes our clutches too.
Both clutches were made by AP Racing - the “special edition” ST200 was given a clutch with a stiffer pressure plate that wasn’t carried over to the ST180 or US ST models. As far as I can tell the friction disc and diameters are basically identical and only the pressure plate is slightly modified - probably similar to most “stage 1” aftermarket clutches which change the cover to move the pivot point of a stiffer diaphram spring, resulting in a higher clamping force, similar pedal pressure but a slightly longer clutch throw.

Automotive single-disc dry clutches (both OEM and aftermarket) are basically all built from the same catalog of fairly standard mix-and-match parts in fairly standard sizes.

The only real difference from one manual transmission car to another is the choice of clutch diameter and whether it’s a “pull” or “push” style diaphram. The rest is just things like mounting holes and flywheel step height, which is why all the different “aftermarket clutch kits” look remarkably indistinguishable from eachother. It’s only when you get to twin/triple disc clutches that the hardware starts to become different and more custom/proprietary

It also means if you really want to you can go to one of the main clutch whilsesaler companies that supplies every aftermarket outfit and have a “custom” clutch of any flavor combination built.

Two examples are Clutches Unlimited (formerly Clutchnet) and California Custom Clutch - both out of LA.

AP racing was formerly a similar type of company based out of the UK selling “high end” clutch and brake kits prior to being acquired by Brembo.
 


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M-Sport fan

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The Gripper LSD should resolve wheelspin with minimal additional maintenance. I don’t know of anyone using it in the US but I’m sure it’ll be superior to the MFactory. I spoke by phone with Tony at Pumaspeed and we discussed their race cars and time trial setups. They use the clutch style diff exclusively and now I understand why.
Does the Gripper require any special/bespoke transaxle fluid, or additives, like the OS Giken, KAAZ and Cusco diffs do??
 


TDavis

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The st200 clutch is an AP Racing clutch. Supposedly it can handle more power than the stock one but I don’t particularly trust anyone’s opinion in this industry. 😂 I just went with my gut and decided to “upgrade”. My intentions of adding more power to this car have been tabled until I achieve maximum grip and the aero is also maximized. I have no need for power if I can’t put it down but when I do build the next engine I’d like to use the trans I’m buying now.
Interesting. I wonder what is different because the stock US model FiST clutch/pressure plate is AP Racing too lol

EDIT: Nvm it was answered
 


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I’ve had more RT660s than I care to count and never had a problem until this year. Eight tires (all heat cycled) cracked all the way across the tread. Some even delaminated. My buddy’s Golf R absolutely ate them at GTA and GL this year.
I checked my tires last night and they were late 2022 production. so I probably haven't gotten to experience any recently produced ones yet then with these issues. I wonder what changed in the production side
 


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Woods247

Woods247

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Does the Gripper require any special/bespoke transaxle fluid, or additives, like the OS Giken, KAAZ and Cusco diffs do??
I was told anything with “LS” but plan to confirm with Gripper. Ideally I’d run Motul Gear 300 LS but I will make sure to use whatever they recommend.
 


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Woods247

Woods247

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I checked my tires last night and they were late 2022 production. so I probably haven't gotten to experience any recently produced ones yet then with these issues. I wonder what changed in the production side
Not sure. It could be me pushing them harder than I have before. It seems most cars running my pace with RT660s have this problem but typically those cars are significantly heavier than mine. Aero adds weight but nothing that should cause a tire failure. It’s a bummer because I really love the tire.
 


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Woods247

Woods247

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Does the Gripper require any special/bespoke transaxle fluid, or additives, like the OS Giken, KAAZ and Cusco diffs do??
Can you please help me interpret this? 75w90 Motul Gear 300 LS should work right?

IMG_3454.jpeg
 


M-Sport fan

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Yes, the Motul should be fine, except it is a bit viscous for our IB6 boxes, which should not be a problem for you in your locale, and the high temp/very hard use you will put that transaxle through.

I am just wondering how the limited slip additive in the Motul will effect the synchro/blocker ring engagement, if at all. [dunno]

I would contact Gripper, if at all possible, and ask all of these questions, as well as just how much additive is necessary for proper clutch pack function.

(On RWD/separate from the gearbox axle apps, most usually run as little limited slip additive as they can in order to achieve full locking, and only enough to allow for no chatter if street driven, and in order to save the clutch plates from excessive wear.)
 


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Woods247

Woods247

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Yes, the Motul should be fine, except it is a bit viscous for our IB6 boxes, which should not be a problem for you in your locale, and the high temp/very hard use you will put that transaxle through.

I am just wondering how the limited slip additive in the Motul will effect the synchro/blocker ring engagement, if at all. [dunno]

I would contact Gripper, if at all possible, and ask all of these questions, as well as just how much additive is necessary for proper clutch pack function.

(On RWD/separate from the gearbox axle apps, most usually run as little as they can in order to achieve full locking, and only enough to allow for no chatter if street driven, and in order to save the clutch plates from excessive wear.)
I wonder if switching to the carbon sycros is a better option. I’ll reach out to them in the morning. Thanks!!
 


Dialcaliper

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I would interpret that statement from Gripper as our gearbox falling under 1.A - Syncromesh gear kits require particular oil for their application

In other words, I would not change to a LS oil unless you've already had good luck running one in our IB6, and in fact not change from whatever transmission oil you're running currently if its working well (Motul?). You might get a little less torque transfer action from the Gripper LSD but it's not going to damage it, and the 6-speed will still shift properly. You might find that its a non-issue

I'd talk to Synchrotech - If the Carbon synchros are more tolerant of friction modifiers than the OEM synchros, you might be able to get improved torque transfer from the LSD by using an LS oil with friction modifiers, but I wouldn't sacrifice the rest of the transmission and shift quality to do it, especially if Synchrotech also recommends against it.
 


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Woods247

Woods247

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Transmission is in route from Pumaspeed. In the meantime I bought a shift knob from a fellow member, tapped it and installed it on the Coolerworx. Looks awesome and feels awesome. I always missed my carbon ST shift knob after upgrading to this shifter with a monster m12x1.5 thread pitch.

IMG_3788.jpeg
 


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