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Is tieing the front pivots to the rear pivots really that necessary? I mean the strut rods are going to deflect no matter what with the double isolated bushings, I think just tieing the k member at the rear pivots to the unibody is all that's really necessary, why add more weight?

Just IMO though.
 

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Is tieing the front pivots to the rear pivots really that necessary? I mean the strut rods are going to deflect no matter what with the double isolated bushings, I think just tieing the k member at the rear pivots to the unibody is all that's really necessary, why add more weight?

Just IMO though.
That's a fair question. I don't know the answer to that really. All of the braces I see being made are tying it all together so I've just copied the general thought.
 

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Kenny Brown's didn't have the strut rod tie in

TCCoA/Kenny Brown

On an unrelated/related note, I wish someone would design a set of these where you don't need to weld a stupid plate or L bend to the frame rail. A C shaped piece of steel plate cupped over the frame rail with a through bolt/sleeve drilled through the frame would be much more DIY friendly to those of us without a MIG and equally effective. Having to go through the same hassle of weld on connectors with the drawbacks of bolt on connectors always made me stay away from this mod, even though it's the one brace I'm actually convinced makes a difference.
 

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Kenny Brown's didn't have the strut rod tie in

TCCoA/Kenny Brown

On an unrelated/related note, I wish someone would design a set of these where you don't need to weld a stupid plate or L bend to the frame rail. A C shaped piece of steel plate cupped over the frame rail with a through bolt/sleeve drilled through the frame would be much more DIY friendly to those of us without a MIG and equally effective. Having to go through the same hassle of weld on connectors with the drawbacks of bolt on connectors always made me stay away from this mod, even though it's the one brace I'm actually convinced makes a difference.
Other than a little weight, what does it really hurt?
 

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What does it solve? Add lightness bro :D

Seriously though, these are bolt in braces, their effectiveness isn't as great as welded anyway, so adding weight for mostly snake oil rigidity to improve handling is counterproductive. The K member is very rigid as it is but it to is bolted on so anything to further strengthen it's connection to the chassis would be more beneficial.
 

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What does it solve? Add lightness bro :D

Seriously though, these are bolt in braces, their effectiveness isn't as great as welded anyway, so adding weight for mostly snake oil rigidity to improve handling is counterproductive. The K member is very rigid as it is but it to is bolted on so anything to further strengthen it's connection to the chassis would be more beneficial.
I think that the ship of "lightness" has sailed.

I'll think on what you've said though.
 

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Hey a 2016 Mustang GT weighs about as much as a V8 MN12 these days, things are more balanced for us than ever if you have the power!
That's true. On paper I've got around 450hp assuming I get it dialed in the way I want. For the purposes I have for the car that power should be plenty with my suspension setup. Besides, when I slide it off the road into the tires on the road course it will be "just a Thunderbird". :laugh:
 

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Discussion Starter #29
I think that the ship of "lightness" has sailed.

I'll think on what you've said though.
Colin Chapman would not approve of my tbird as a track car.
I've pulled something like 800Lbs out of this car (I weighed all the tar and bits off the car) and there's not much I could strip off anymore; I've removed every extraneous wire I could trace in the harness inside the cabin and underneath the hood (when possible). Sure, I could do things like remove ABS but I know what kind of drivers I have on my team (myself included).

Bottom line is that she's still a porker (3150LB on corner scales the last time i checked -- with the V8, full fluids, but no driver). Car is still more 60/40 F/R even with the battery relocated to the passenger footwell.

I'm skeptical about the front brace (esp since i noticed that there are scuff marks on the bottom corner probably from the last offroad excursion) but the rear brake makes sense and is easy to implement. I may actually just build all four braces as I have the time but will make the front ones removable (already drilled the hole for the 3/8" bolt in the kmember).
 

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Interesting read!

I didn't see anyone reply to your question about your rear LCA bushings. I'd say they need to go! Replace them with poly bushings and this will increase her handling. If you haven't already done so, and while you're replacing the rear LCA bushings, also replace the rear LCAs themselves with MK8 rear LCAs. That'll save you some weight as well. While you're doing that, you can do the toe compensator delete mod, which while not much, it'll save you a tiny bit more of weight.

If you don't already have one, get a '93 (has to be '93) MK8 drive shaft. Or get a Denny's Drive Shaft for a bit more coin. You'll save weight, and since it's rotational weight you'll be saving, you'll also "make" more HP. And speaking of rotational weight, perhaps go even further and get some lightweight lug nuts? Of course, at that point, you're just trying to shave off thousandths of a second at that point.
 

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Discussion Starter #31
So I've removed my front driver's side strut assembly (it's the most worn) and my passenger rear shock so I can start upgrading my suspension.
1) I don't have the new front bilstein shocks yet but man, after 6 races (4 real ones) the front Sensatracs are blown. It does rebound (eventually) but it's clear that this is the second one of the pair I'm going to cut and use as a base for the Bilstein S6G-5555 units.
I wish I had access to one of these. Too bad they cost about 16 tbirds.

2) Its amazing what you find when you start going over your car in more detail. While I had probably another race left in my passenger side brake pads, when I went to remove my driver's side strut assembly I noticed that my driver side outside pad had less than 1mm left on them. This kind of makes sense since most of the time we are turning right at Sears Point but it's still annoying to spend more on a set of race pads than I paid for this car originally (Porterfield AP804-R4e pads are spendy). Oh well.
 

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Discussion Starter #32
Interesting read!

I didn't see anyone reply to your question about your rear LCA bushings. I'd say they need to go! Replace them with poly bushings and this will increase her handling. If you haven't already done so, and while you're replacing the rear LCA bushings, also replace the rear LCAs themselves with MK8 rear LCAs. That'll save you some weight as well. While you're doing that, you can do the toe compensator delete mod, which while not much, it'll save you a tiny bit more of weight.

If you don't already have one, get a '93 (has to be '93) MK8 drive shaft. Or get a Denny's Drive Shaft for a bit more coin. You'll save weight, and since it's rotational weight you'll be saving, you'll also "make" more HP. And speaking of rotational weight, perhaps go even further and get some lightweight lug nuts? Of course, at that point, you're just trying to shave off thousandths of a second at that point.
1) I spoke to Dan/ddubb about the rear LCAs I am inclined to agree with him that replacing them will be a giant PITA. The car isnt rusty (California) and has been in pretty mild weather so while the inner bushings seem worn, the side to side play seems pretty limited (stuck a pry bar in there and they move but only slightly -- few mm). It doesn't seem sloppy.
I probably would be more inclined to do it if I had a spare set of LCAs to do the swap on and just swap them out but I scrapped those years ago.

2) the Toe end compensators seem more worn and I bought two for $40 on special which I will swap out. Your

3) As far as upgrading the tbird with MK8 bits is concerned, I have thought about it (upper rear LCAs, rear LCAs, driveshaft, rear pumpkin) and the economics don't make sense (shipping + the value that people place on them here on TCCOA). I'm also a little concerned about the potential to crack a rear diff should the car go offroad or run over some piece of crap on the track (not unheard of).
- Bottom line: I'm unwilling to spend the cash to save a the tens of LBs nor do I have the time in the post-toddler world I live in to part out another car (by far the cheapest route to cheap MK8 parts).
- At this point, the cheapest way to save weight on the track will be to put all our drivers on diets and make sure my drivers take a crap before their stints.

4) Toe compensator delete: this is something I had never heard of before. I just read this discussion and IMO, it only makes sense if I replace my rear LCA inner bushings with poly. Otherwise, fresh toe comps will help keep the rear tires straight for minimal effort/cost (on special, they were $40/pair from pepboys).

-g
 

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Discussion Starter #33
So the Bilstein S6G-555 shocks came in today and the one thing I didn't realize was how small the body of these "circle track" shocks need to be in order to fit in this application. While this might not be an issue for the kind of races Paul/tbirdtess (20-30min of crazy up and down bumping) does OR for street uses, I'm not 100% confident that these will last in a lemons race where the car is going up and down hills (Sears point is pretty hilly) for 8-9 hours straight. While Sears Point is not like racing Baja (where every vehicle's shock has an external reservior)

FACTS
- This new bilstein shock has got less oil capacity compared to a stock tbird strut assembly. If I had to guess, probably 50-75% the capacity based on external volume.
- When hydraulic oil gets too hot, it starts breaking down seals. While the Bilsteins are rebuildable, the cost is similar to what these dampers cost new (Service)

UNKNOWN:
- Are bilsteins filled with some magical hydraulic fluid that is that much better than what you would find in a Sensatrac? Doubtful.
- Will these shocks overheat? potentially.

While I will finish building out these strut assemblies, a pair of Tokicos might be in my future.
I hope not. :)
-g
 

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So the Bilstein S6G-555 shocks came in today and the one thing I didn't realize was how small the body of these "circle track" shocks need to be in order to fit in this application. While this might not be an issue for the kind of races Paul/tbirdtess (20-30min of crazy up and down bumping) does OR for street uses, I'm not 100% confident that these will last in a lemons race where the car is going up and down hills (Sears point is pretty hilly) for 8-9 hours straight. While Sears Point is not like racing Baja (where every vehicle's shock has an external reservior)

FACTS
- This new bilstein shock has got less oil capacity compared to a stock tbird strut assembly. If I had to guess, probably 50-75% the capacity based on external volume.
- When hydraulic oil gets too hot, it starts breaking down seals. While the Bilsteins are rebuildable, the cost is similar to what these dampers cost new (Service)

UNKNOWN:
- Are bilsteins filled with some magical hydraulic fluid that is that much better than what you would find in a Sensatrac? Doubtful.
- Will these shocks overheat? potentially.

While I will finish building out these strut assemblies, a pair of Tokicos might be in my future.
I hope not. :)
-g
Is their a reason that you're not interested in trying the route I went?
 

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Discussion Starter #35 (Edited)
Is their a reason that you're not interested in trying the route I went?
Bilstein S6G-5555 aka F4-BE3-A213-M6 - $79/ea
Bilstein 34-050224 / inserts from 91-99 Mitsubishi 3000GT - $131/ea (Tirerack closeout)


At that price, I might as well consider the Tokico Illumina 2s (#EU3689) @ $146/ea


Seeing as how the S6Gs are also bolted in where yours are inserted (and maybe forced/fit), I could always return the S6G-5555 if I decide they won't work for my needs.
The body itself is 9" long and 1.56" inches in diameter.
Even if it's 100% full of fluid (it's not - the shaft has to go somewhere and there needs to be space for gas to add pressure), we are only talking about 17.2 square inches or 9.5 fluid ounces of oil. This is a physics issue so I don't believe the Koni inserts will fare much better.

I'll update this thread with the sizing of a stock monroe Sensatrac #71845
Regards,
-g
 

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Bilstein S6G-5555 aka F4-BE3-A213-M6 - $79/ea
Bilstein 34-050224 / inserts from 91-99 Mitsubishi 3000GT - $131/ea (Tirerack closeout)


At that price, I might as well consider the Tokico Illumina 2s (#EU3689) @ $146/ea


Seeing as how the S6Gs are also bolted in where yours are inserted (and maybe forced/fit), I could always return the S6G-5555 if I decide they won't work for my needs.
The body itself is 9" long and 1.56" inches in diameter.
Even if it's 100% full of fluid (it's not - the shaft has to go somewhere and there needs to be space for gas to add pressure), we are only talking about 17.2 square inches or 9.5 fluid ounces of oil.


I'll update this thread with the sizing of a stock monroe Sensatrac #71845
Regards,
-g
OK, I see. I was looking at this purely from a performance aspect since anything decent isn't available without customization.
 

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Discussion Starter #37
So I took a deeper look at the S6G-5555 shocks I purchased today with the cut down strut assemblies and compared them to a stock SC strut.

The short answer is that I need to look in a different direction as Paul's instructions + pics didn't make things totally clear.

1) it appears that the S6G-5555 struts are too short compared to the S7G-5555 unless you want to bolt the bottom of the strut higher up the cut down strut assembly -- above the bottom bracket tabs instead of 1/2" lower from the top.
This means that there will be a thinner piece of metal (just the strut body) supporting the 1/2" bolt going through the bottom of the Bilstein. Running the bolt through the bottom bracket tabs means the metal will be over 2x thicker on each side.

2) I could remove the top eyebolt but I don't see an easy way to remove the lower nut without potentially marring up the shock shaft. Even with an impact gun, the shaft just spins before the nut comes off. The challenge here is that while the shaft can fit through a stock top mount, the shaft+nut won't go through. BOTTOM LINE: Unless you remove this nut, you will need to fabricate a custom top mount.

http://forums.tccoa.com/44-suspension/140125-bilstein-racing-shocks-front-shock-custom-design.html

NEXT STEPS:
I have a decision to make:
A) Swap the S6G-5555 for S7G-5555 struts (thanks Summit Racing) and figure out how to remove this blasted nut
B) Go with the Bilstein 3000GT inserts and fabricate a top mount with a bigger hole (customized top mount)
C) Go with Tokicos Illumina 2s and figure out how to manually switch the shocks from hard to soft.

Right now I'm leaning towards 'C'.

Questions
1) Any ideas on how to remove this damned nut? if so, I might just swap for S7G-555 shocks
2) With Tokico ARC shocks, is there a way to manually switch from hard to soft modes? Meaning, can I just use some pliers (or a specific tool) or do I need to rig up an ARC actuator to switch them?
- In a perfect world, my newly painted to look like crap ARC shocks will be soft when needed but can be switched to full FIRM mode when I get ready to roll off onto the track.
3) With ARC shocks set to hard but no actuator in place, will it stay in FIRM damper mode or do I need to wire an ARC actuator in place with the right voltage setting to keep them set?
 

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A way to get that nut off may be to take a few of those sheets of rubber you use to remove lids off of jars and wrap it around the shaft and then use a pipe wrench to hold the shaft over that (so you don't mar the shaft) and then use an impact gun. If that doesn't quite do it, put a torch on that nut and then use an impact gun. If none of that works then maybe think about cutting the nut off while being careful not to mar the shaft or the threads.

You're in full on science project at this point. Racing is expensive.
 

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Discussion Starter #39
A way to get that nut off may be to take a few of those sheets of rubber you use to remove lids off of jars and wrap it around the shaft and then use a pipe wrench to hold the shaft over that (so you don't mar the shaft) and then use an impact gun. If that doesn't quite do it, put a torch on that nut and then use an impact gun. If none of that works then maybe think about cutting the nut off while being careful not to mar the shaft or the threads.

You're in full on science project at this point. Racing is expensive.
Your suggestion on removing the nut makes sense and I'd try it -- except that I already confirmed that the S6G-5555 are too short (will require the horizontal bolt to go through just the body of the cut strut vs. the body+lower brackets). There's no sense in risking marring up a shaft for a strut I'm going to return anyway.

I now need to decide between Tokico, S7G-5555, or go with your 3000GT bilstein route.

I was leaning towards the Tokico's for the larger size (more oil internally) but after reading some more reviews on TCCOA/SCCOA (esp the guy that commented that SC shocks with 60K mi were stiffer than Tokico Illumina 2s set to firm), I'm skeptical about them being a good match for the Bilstein rears I already have installed.

One other reason to go down the 3000GT Bilstein route you chose is that they were designed as inserts -- the body looks larger (therefore hopefully there's more fluid to heat up) and the piston shaft portion (the piece that moves back and forth) is significantly beefier. I guess that's where the extra $50-60 bucks/ea goes.

Compare my pic (attached) with this one I found showing a Koni vs Bilstein insert. This guy used the same one you picked for a Nissan application (for autocrossing)


Need to ponder this further.
-g
 

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Your suggestion on removing the nut makes sense a.....
Well, the guy that had the original idea of the 3000GT solution had done his homework on the specs of that shock insert so it sure seems like it's about the perfect substitute. The only concern I have my setup is the durability of the top mount but I think I've done as much as is reasonable to make sure that it lasts. A better top mount would be nice but I need some assistance in determining the kind of components for the top mount.
 
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