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Old 08-11-2020, 10:52 AM   #2226
subydude
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Swapping to spherical bearings will actually add to the wear on other systems in the car because it directly transfers forces. Poly acts like a spring and can bind, so it effectively ups the spring rate of whatever system it's in. It can deflect for sure, but I would bet that going spherical (which reduces overall spring rate) will have the same, if not more tire wear. Wheel bearings go out on those cars on r-comps. Swap to the 5x114 knuckles to solve this. It's not the poly that's hurting those.

I have run sphericals in the rear suspension for years without wallowing out any holes. I recently sphericaled the OEM arms up front but expect the same results of "I need a tad more spring rate".

Like Ham said, there's a lot of common issues in SM, and until you spend some time massaging the inner and outer fenders you'll rub, and even then you'll want more grip so you'll go to a bigger tire, which will rub again, so you'll modify again
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Old 08-11-2020, 06:15 PM   #2227
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Thanks for the help guys! To be clear, my tires have about 1/2" clearance from the inside edge of the tire to the unibody at the height of the center of the axle, but it is flexing the lateral link bushings enough that I'm rubbing pretty aggressively there. Also, due to budget concerns I'm running a 255/40/17 BFG Rival (yes, 200TW) and having these issues. Can't imagine how it would be with some purple crack of modest size.

5x114.3 knuckle conversion is in the plans, but it will be a big expenditure so for now I'm getting good at pressing wheelbearings. haha.
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Old 08-11-2020, 10:03 PM   #2228
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I run a 335 on a 18x12 +20 wheel with a 5mm spacer our back and don't rub on the inner unibody. That's what's possible in SM.
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Old 08-11-2020, 11:56 PM   #2229
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I run a 335 on a 18x12 +20 wheel with a 5mm spacer our back and don’t rub on the inner unibody. That’s what’s possible in SM.


Yeah! I love the crazy.
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Old 08-12-2020, 08:39 AM   #2230
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Slight detour... Do any of you do anything to protect or shield your sphericals from dirt / salt / etc? I get tempted to add more sphericals, but my car also pulls winter duty (only about a dozen outings a year though).
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Old 08-12-2020, 09:09 AM   #2231
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Slight detour... Do any of you do anything to protect or shield your sphericals from dirt / salt / etc? I get tempted to add more sphericals, but my car also pulls winter duty (only about a dozen outings a year though).
A lot of higher end sphericals come with wipers and a high level of corrosion resistance.

Used to deal a lot with spherical when I was doing custom suspension work for the military.

The RBC Duralube bearings were insanely impressive in testing. Problem is that they tend to run in large sizes. Always nagged the rep that they needed to make motorsport sizes...then again sphericals are consumables on pro level cars.

Those spherical boot covers can easily trap humidity/water and accelerate corrosion.


As for the fear of wallowing holes, for the rear lateral links, the clamp load should be what's holding everything in place, not the hole through the subframe.
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Old 08-12-2020, 09:59 AM   #2232
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I have actually sprayed mine with clear coat before. Not the greatest idea, but it keeps them looking reasonable. I also buy the ones that self lubricate and say they resist corrosion.
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Old 08-12-2020, 12:30 PM   #2233
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Originally Posted by tsrapophis View Post
Thanks for the help guys! To be clear, my tires have about 1/2" clearance from the inside edge of the tire to the unibody at the height of the center of the axle, but it is flexing the lateral link bushings enough that I'm rubbing pretty aggressively there. Also, due to budget concerns I'm running a 255/40/17 BFG Rival (yes, 200TW) and having these issues. Can't imagine how it would be with some purple crack of modest size.

5x114.3 knuckle conversion is in the plans, but it will be a big expenditure so for now I'm getting good at pressing wheelbearings. haha.
I'm using Voodoo13 lateral links and sti pink trailing arms, so only the rear Lateral link bushing (at the knuckle) and the rear trailing arm bushing (at the knuckle) are still rubber/poly. Also on street tires.

The only wallowing out I've experienced is my trunk hinge pins that are creaking and popping as the body flexes.

As for wheel bearings, you can switch to 08-14 front knuckles for bolt on wheel bearings (they seem to be stronger than the press-in bearings so far.)

http://bbs.22b.com/forums/showthread...avy-Track-use&
(it's a bit of a lengthy thread, but there's some useful info in there)

Nothing for the rear knuckle yet though
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Old 08-12-2020, 12:50 PM   #2234
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The 05-07 are bolt in front wheel bearings, and I think they're the same as the 08-14. I ran 07 front knuckles on my autox car for years without issue on big hoosiers.
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Old 08-12-2020, 01:25 PM   #2235
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08-14 5x100, it's a cheaper interim solution vs buying axles, coilovers and wheels. Substantially cheaper than LIC as well. The bearings are a different bolt hole pattern (into the knuckle) vs the 5x114 bearing. 08-14 knuckles move the tie rod as well, so check bump steer.
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Old 08-12-2020, 01:55 PM   #2236
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Ah, I didn't think about the WRX stuff. Although I feel like it's a bandaid solution that will cost you more in the long run. It makes way more sense to just buy the 5x114.3 stuff and do it all at once vs spending money and time swapping to another 5x100 knuckle....just to swap to 5x114.3 later.
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Old 08-12-2020, 03:08 PM   #2237
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Probably true, but it's paying for itself with bearing longevity so far.
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Old 08-14-2020, 04:28 PM   #2238
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Quote:
Originally Posted by T-37 View Post
08-14 5x100, it's a cheaper interim solution vs buying axles, coilovers and wheels. Substantially cheaper than LIC as well. The bearings are a different bolt hole pattern (into the knuckle) vs the 5x114 bearing. 08-14 knuckles move the tie rod as well, so check bump steer.
Thanks for the info, I didn't know about the 08-14 conversion. Most of my problems seem to come from the rears lately though. I might just have to deal with the bearing situation for awhile until I can do a 5x114.3 conversion.
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Old 09-08-2020, 01:30 PM   #2239
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Working on a prototype to improve cooling of my A2W system.
Any issues with the SM rules looking at this?
I'll test it out in the next few days, do you think I'll get good airflow at this spot?


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Old 09-08-2020, 02:34 PM   #2240
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It will get more air flow than if it were in the trunk simply because it's out in mostly free air. Are you planning on putting a wing above it?

I don't see any rules issues with that location. What temps were you seeing that made you want to move it there vs running a bigger cooler core?
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Old 09-08-2020, 03:21 PM   #2241
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Quote:
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It will get more air flow than if it were in the trunk simply because it's out in mostly free air. Are you planning on putting a wing above it?
I don't see any rules issues with that location. What temps were you seeing that made you want to move it there vs running a bigger cooler core?
Wing might come in a few years, but not yet. You see issues with both?

For temp I'm seeing IAT temp around 155-170 at the end of the course with current setup (12x24x1 rad in the car where the backseat is with 2 fans, no rad in front) and it takes about 10min. of cool down between runs with trunk and door open, ice can help if I get a rerun. With the US border closed I'm back on pump gaz for local events, these temps are a bit too much, I pull 6 degrees of timing and reduce boost a few psi to make it safe at these IAT level.

I'd also like to be able to lap the car a bit on pump gaz, which is not at all possible with current cooling performance.

I also suspect a bit of heat soaking at the intercooler since IAT rise faster than water temp and get back rapidly after the end of the run to the normal range compare to water temp.
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Old 09-08-2020, 03:43 PM   #2242
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This sounds like there are issues other than water core location that need to be solved first. Namely, a more efficient heat intercooler along with a bigger radiator. 155-170 IAT under load isn't that bad on pump gas if you have forged pistons. Not optimal, but not horrible either. I see 145-150 in my pump gas STi when I come out from grocery shopping or what not in the SE and it's fine.

Lapping it is definitely more taxing, and you're going to need a much bigger core to deal with that. Finding the equilibrium point of the system will be key to hot lapping or track day performance. You'll find that you keep upsizing until things are big enough to deal with the heat produced most likely.

Heat soaking the IC can be two things (generally). First is an undersized core, which is common due to packaging issues. If you can up size it, that's a good path for track driving. Second is too slow, or too quick of water circulation. Too slow and the water is absorbing excessive heat and can't cool any more. Too fast and the water is passing through the IC before it can absorb enough heat. I would lean toward the undersized core being the bigger issue.

As always, grain of salt since my experience with AWIC is limited. I've dabbled, but nothing excessive personally. I have watched a lot of other people deal with it and they generally all start small and then go big on cores and coolers. When it's working, it's great and you can shed some incredible heat. When it's not it's super frustrating.
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Old 09-10-2020, 11:53 AM   #2243
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Jimminy Cricket!! Did you ever get the logged data for your set up? I recall going rather in depth on it in here, or it was probably in your build thread.

At minimum I still want to see water temp in and out of the intercooler and then in and out of the exchanger. If I recall, you were running two exchangers...right?
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Old 09-10-2020, 03:00 PM   #2244
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Jimminy Cricket!! Did you ever get the logged data for your set up? I recall going rather in depth on it in here, or it was probably in your build thread.
At minimum I still want to see water temp in and out of the intercooler and then in and out of the exchanger. If I recall, you were running two exchangers...right?

Did not have lot of time to spend on the car lately, still running only 1 temp sensor on the system and I can monitor IAT during the run with the linkecu. I'll probably add an extra sensor during winter season for better understanding what is going on and plug into the ECU. Trunk radiator is working quite well, it's able to cool down at 2C per minute for 15 liter of water from 20C over ambient to 10C over ambient at 30mph. In similar condition the radiator in the car with 2 fan is cooling around 0.5-1C per minute. I could easily double the size of the trunk rad if required. I now know there is a good flow of fresh air in that spot and I'm not stacking stuff in front, which is really good. The A2W project is now 2 years old!
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Old 09-14-2020, 07:52 PM   #2245
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I'm loving the trunk mount. If you don't currently have a wing, why not make the mount out of Lexan and make it like a Nascar wing?

I always figured that an A2W setup for autocross would involve a cooler full of ice water that gets dumped and refilled between runs.
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Old 09-21-2020, 01:25 PM   #2246
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I always figured that an A2W setup for autocross would involve a cooler full of ice water that gets dumped and refilled between runs.
Frozen water bottles works really well for keeping a quick swap without draining.

Using a bunch of 20 oz soda bottles is better than one large milk jug, for instance, as you have more surface area.


When the run is over, just grab the bottles and swap with frozen ones.
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Old 09-21-2020, 02:29 PM   #2247
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Frozen water bottles works really well for keeping a quick swap without draining.
Using a bunch of 20 oz soda bottles is better than one large milk jug, for instance, as you have more surface area.
When the run is over, just grab the bottles and swap with frozen ones.

+1. Ice is not that efficient and it takes a lot of ice, almost a full bag between runs and if you get staged more than a few minutes your back to water over ambient to start with. It's almost impossible to keep water under ambient. Frozen water bottle works better and helps keep it close to ambient while staged.



First autocross with the new rad prototype. The trunk mount rad is working relatively well. I used to see 10-12C water temperature increase over a 1min. run, it's now 5-6C for a run. ECU logging was not working so I couldn't see the IAT graph, but I was definitely keeping more power at the end. I could easily fit a bigger rad if needed, but that's a very good start.
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Old 09-21-2020, 02:44 PM   #2248
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Something a lot of people don't consider using bagged ice is how your neighbors will feel in grid having a bunch of water constantly dumped on the ground with tools, helmets, whatever sitting on the ground next to you.

Also, 3 bags of ice is $6ish, which isn't a ton, but it's just another expense and logistic to track.

I'm honestly surprised by the number of people who are worried about inlet temps. As long as you're below like 180ish on E85 and 150ish on pump gas (assuming forged internals) it's fine. Don't worry about it and just keep going. Even above that it's fine for short stints.
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Old 09-21-2020, 03:23 PM   #2249
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Something a lot of people don't consider using bagged ice is how your neighbors will feel in grid having a bunch of water constantly dumped on the ground with tools, helmets, whatever sitting on the ground next to you.
Also, 3 bags of ice is $6ish, which isn't a ton, but it's just another expense and logistic to track.
I'm honestly surprised by the number of people who are worried about inlet temps. As long as you're below like 180ish on E85 and 150ish on pump gas (assuming forged internals) it's fine. Don't worry about it and just keep going. Even above that it's fine for short stints.

Yep the extra logistic of ice is a bit annoying, especially if you drive your car to the event like me most of the time. Running pump this year so I need to reduce IAT by 20-30F on very hot day to keep it safe, getting there slowly. On E85 current setup would already be good enough, but I like a little safety margin!
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Old 10-05-2020, 10:04 PM   #2250
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Something a lot of people don't consider using bagged ice is how your neighbors will feel in grid having a bunch of water constantly dumped on the ground with tools, helmets, whatever sitting on the ground next to you.
Yup, thus the bottles suggestions. Lessons learned from cool suits and endurance racing.
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