NikwoaC's "Commitment Issues" Engine Build

Nice upgrades... I think you are misremembering what is and is not advised when it comes to the 4 link rear and binding. If you had uppers and lowers with all poly bushings that WILL cause bind on the 4 link rear. However you said you used spherical on the housing end of the uppers which eliminates the binding that would be there with poly bushings.

Technically, all the pivot points in a triangulated 4-link must both pivot and twist as the suspension goes through its travel, forcing the bushings to deform somewhat. So, anywhere you have a poly or rubber bushing, you are creating some "binding" in that sense. Spherical bearings on one end of the control arm doesn't remove this reality from occurring on the other end. Although, since spherical bearings can articulate multi-axially freely (unlike a poly bushing), they don't artificially contribute to spring rate and do allow the suspension to travel more freely. Of course, you can't really run spherical bearings at both ends of a control arm- not only because it would rattle your teeth out, but also because you need something to prevent the control arm from rotating about its longitudinal axis. IMHO, the Steeda 3-piece urethane bushing is a pretty clever approach to make a poly bushing behave somewhat like a spherical bearing, while still preventing the control arm from rotating about its longitudinal axis.

To be fair, there are probably some cheaper and/or older aftermarket control arm bushing designs that probably didn't allow sufficient off-axis flex (binding), which is maybe where this urban legend came from.

If you're not already familiar, @Warhorse Racing on YouTube has a pretty comprehensive video on running Steeda control arms with all poly bushings in an autocross application. His delivery is slightly cheesy, but so am I, so I dig it.
 
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Nice upgrades. 8.8" rears can be out of alignment from the factory, and racers will often have them straightened and then the tubes welded & braced. I wonder if there's an issue with yours. I wouldn't overthink it, unless you're getting inexplicably strange tire wear patterns.
This was brought up in my discussions with Steeda. The car has never been in an accident and has never showed any symptoms of having something wrong with the rear end geometry, but I suppose it's possible. I lean toward it being more of an issue with Steeda's bulky and squared-off flange geometry, though. Their aluminum arms are larger in this area than any of their other arms.

This photo from Motor Trend (NOT mine) kind of perfectly shows the half-octagonal shape of the Steeda flange, VS the factory arm that is rounded in that area. The Steeda arm ends of being about 3/16" larger radially about the bolt CL, on top of not being rounded.

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Here you can see where the interference was on my car (yes, the axle is crusty, no the rust isn't causing the interference :rolleyes: Also, yes, I replaced that brake line.

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Here's what the arm looked like after I "reshaped" it.

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Anyway, this brings me to where I am today. As you guys can see from this thread, I built this engine 14 years and about 35K miles of hard use ago. It has held up (surprisingly) very well, but at this point the timing cover gasket and rear main seal have started leaving so much coolant and oil on the garage floor that I can't take it any more. Also, the leaky rear main (and my driving habits) has basically completely trashed the clutch.

It's kind of unfortunate, because I was planning on finally doing the 351 swap next year, but the I wasn't going to get another season out of this engine without changing these seals.

Also, my T5 died. For the 4th time. So, I'm going to use this opportunity to swap in the TKO that I built something like 5-6 years ago. It's a 500 that I bought used, probably around 2015, and fully rebuilt with carbon fiber blocker rings and a modified selector finger. That was back when I did all my transmission business with Astro Performance, which, as I understand it, has since closed their doors. I'm pretty sure I have photos of the full rebuild process around somewhere, but until I find them please enjoy this after photo of the TKO on my workbench. :D

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Senseless advice.
There is always something better out there and if his engine is NA he's not going to break a TKO.
Be no different than telling a guy with a TKX to buy a t56 magnum.
While I’d usually agree , the tko will never shift like a tkx. I had a 600 with all the upgrades and it still shifted horrible compared to a t5 or 56 at the time.

After installing a tkx in a customers car
I’m a firm believer in it. It’s the closest thing to shifting as smooth as a t5 with the tko strength now.
 
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While I’d usually agree , the tko will never shift like a tkx. I had a 600 with all the upgrades and it still shifted horrible compared to a t5 or 56 at the time.

After installing a tkx in a customers car
I’m a firm believer in it. It’s the closest thing to shifting as smooth as a t5 with the tko strength now.
I don't doubt the smoothness.
But if you are going from one directly to another, obviously you may notice.
I went from a T5z to the TKO and it never really bothered me.
Besides, if i'm selling my TKO, it's for a t56 magnum at that point.

Now if you had nothing and starting new, that would change things.
In that case you buy the best you can afford.
But he has the trans and it's rebuilt. The secondary market most likely wouldn't be all that friendly to sell one and buy the other.

I don't think the debate is about which trans is better, it's the TKX, but as i said, there is always something better you can buy.
 
Nic, when you blew your T5s, were you always on a DR or stickier tire? What clutch? Do you have any quarter mile times since the old days?

After I blew my first T5 at only ~320 rwhp, I went to TKOs (2x 3550s and 1x TKO), and subsequently to T56s. I agree with the comments that I never liked the way they shifted, whereas the T56s have always shifted very well. My current daily driver, Black Jack, was on a T5 making ~270 rwhp and I beat the utter dog:poo: out of it, getting a best of 12.63@108mph. The reason I believe that trans lived was because I kept the car on 225/50/16 all-seasons with no more aggressive than a King Cobra clutch. It's still on my garage floor waiting to go back into Black Jack before I eventually sell the car (if ever).

I'm just curious if you ever experienced failure while making the clutch and tires 'the fuse'? FWIW, I am an advocate, in a street fox with a short rear gear, of the wide-ratio T56s (2.95 1st, .5 6th), or T56 Magnums. I hear ya on not wanting to spend more. I guess the important thing is to stop snapping transmissions for the time being, and hopefully you get along with the way yours shifts. With the upgrades, maybe it'll be a better experience than any of mine were.
 
My comment was more about the fit of the TKX in cars... The TKO requires some cutting on the tunnel on some cars due to its size, and there can be some driveline alignment problems again due to its size.... NOT sure if the Fox bodies have this but Mopars and Camaro's do.....
As to the Magnum 6 speed, I see no reason for a double overdrive my self......
LOTS of complaints with TKO's... Its not made anymore for a reason
 
Nic, when you blew your T5s, were you always on a DR or stickier tire? What clutch? Do you have any quarter mile times since the old days?

After I blew my first T5 at only ~320 rwhp, I went to TKOs (2x 3550s and 1x TKO), and subsequently to T56s. I agree with the comments that I never liked the way they shifted, whereas the T56s have always shifted very well. My current daily driver, Black Jack, was on a T5 making ~270 rwhp and I beat the utter dog:poo: out of it, getting a best of 12.63@108mph. The reason I believe that trans lived was because I kept the car on 225/50/16 all-seasons with no more aggressive than a King Cobra clutch. It's still on my garage floor waiting to go back into Black Jack before I eventually sell the car (if ever).

I'm just curious if you ever experienced failure while making the clutch and tires 'the fuse'? FWIW, I am an advocate, in a street fox with a short rear gear, of the wide-ratio T56s (2.95 1st, .5 6th), or T56 Magnums. I hear ya on not wanting to spend more. I guess the important thing is to stop snapping transmissions for the time being, and hopefully you get along with the way yours shifts. With the upgrades, maybe it'll be a better experience than any of mine were.

The car has only ever been on summer-type street tires, never been flat-foot shifted, and no, I haven't been to the drag strip since I clocked that 12.9 run a million years ago. To be fair though, I only ever sheared teeth off gears once. 2 of the 4 failures were related to the synchro assemblies. While I haven't pulled it apart yet, this last failure was a weird one. It never made any noise, the lever just doesn't want to move. I imagine something in the internal gear selector assembly is either galling or a detent somewhere came loose and is seized.

This trans also has a cracked case from an over-tightened drain plug, so it's just very tired and ready for retirement.
 
Off topic but since you mentioned Astro Performance not being in business anymore. I saw GForce sells a rebuild kit for the T5's thats supposed to handle quite a bit of power. I think its for $1,900? Is that kit any good? Just thinking out loud, i don't have a need to upgrade my transmission or anything at this time.
 
Off topic but since you mentioned Astro Performance not being in business anymore. I saw GForce sells a rebuild kit for the T5's thats supposed to handle quite a bit of power. I think its for $1,900? Is that kit any good? Just thinking out loud, i don't have a need to upgrade my transmission or anything at this time.
Much better options than sinking $1,900 into a T5
 
Off topic but since you mentioned Astro Performance not being in business anymore. I saw GForce sells a rebuild kit for the T5's thats supposed to handle quite a bit of power. I think its for $1,900? Is that kit any good? Just thinking out loud, i don't have a need to upgrade my transmission or anything at this time.

If I were to do it over again, I'd probably either pony up for a TKX or try to find a good deal on a used T56. I probably wouldn't go with a T5 platform.
 
Here are some shots of the teardown.

Oil soaked bellhousing.

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Roasted flywheel.

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The pressure plate looks pretty rough too. I'm going to have the flywheel resurfaced and just try to clean up the pressure plate and squeeze another season or two out of it, with a new friction disc. The old friction disc was almost down to the rivets. This is a Ram HDX, BTW.

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