Installed a Tremec Magnum XL in my S550

[db252]

No issue with the flywheel, couple thou interference fit same as OE, bores mic’d exactly the same and the flywheel pulled down square with the OE bolts without issue. Only issue so far is they put the wrong ARP flywheel bolts in the box so I’m just gonna order the right ones off Amazon.

Awesome! Except for the ARP part. Are you by chance able to get me the bore diameter that the flywheel goes over in mm? I’m curious if they corrected it or it never changed.

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[aleccolin]

Awesome! Except for the ARP part. Are you by chance able to get me the bore diameter that the flywheel goes over in mm? I’m curious if they corrected it or it never changed.

Both flywheel bores were about 1.745-1.747” and the register on the crank is right about 1.75”, plus or minus a few tenths. That’s approx equivalent to 44.5mm, so idk if that’s the intended bore, but if so it’s pretty much right on. I’ve had this clutch set for several months already, so I’m not sure where it lands in the manufacturing history, but it isn’t very recent.

 

[db252]

Both flywheel bores were about 1.745-1.747” and the register on the crank is right about 1.75”, plus or minus a few tenths. That’s approx equivalent to 44.5mm, so idk if that’s the intended bore, but if so it’s pretty much right on. I’ve had this clutch set for several months already, so I’m not sure where it lands in the manufacturing history, but it isn’t very recent.

Thanks for that info and 44.5mm is what was here on this end and went with two flywheels that weren’t close. He ended up going a different route. Looking forward to your experience with the clutch.

 

[aleccolin]

The Tilton hydraulic release bearing part number correct for this application is 60-6105 ($382 from Summit). Before ordering from Summit I asked Tilton and was told 60-6104 ($335 from Summit) which is wrong, being a pilot tube mount style. The mounting plate and hardware by itself is part number 62-899 which is $128 from Summit. I'm not paying that when there's only a $50 difference between those two to begin with.

The correct part number for ARP flywheel bolts is 156-2108. These are not TTY like the OE flywheel bolts, and are installed with Loctite on the threads and ARP lube under the heads when torquing down. I'm not sure I prefer this over the OE TTY bolts, but since all the Ford dealers within a 100 mile radius of me are retarded and don't stock these common, single use bolts, I might as well just order the ARP bolts because I can get them faster and that is what comes with the clutch set anyway. If only they had put the right ones in the box.

I never intended to hijack this thread, but hopefully someone is saved some time/money/headache from all of this.

 

[aleccolin]

Called Tilton, they're currently corona-closed, but have a guy coming in Thursday for some small shipments so they're sending me the correct flywheel bolts.

They're also selling me the HRB adapter plate for dealer price which is $98, so I'm still spending more than I should, but I also don't have to wait 2-3 weeks. I was about to say fuck it last night and just bolt up the OE throwout, but the bolt holes didn't line up - @db252 how are you making those work?

I feel better about the flat face Tilton HRB regardless, the contact point of the clutch fingers is at the very outer edge of the flat face of the Ford bearing, which is also constant-contact. It hits right in the sweet spot on the face of the Tilton bearing, which uses a 0.125" air gap.

I fully assembled the clutch to the flywheel and used my shop press to take tension off so I could center the captured disc. Not a big deal, but not everyone has a press. I get the feeling they were still working the bugs out of their ST-246 line when I ordered mine back in August.

I'm going to need an adapter fitting from the -4AN female fitting on the HRB to the male QD fitting, fortunately Earl's makes one P/N 652504ERL for $15. I'll use the OE clutch line and the OE elbow and some sort of Adel clamp or something to secure everything to the bellhousing.

Spent some time last night with an India stone hitting all the flat mating surfaces of the flywheel, block plate, bellhousing, and the Bowler indicator plate. I'm tempted to throw the flywheel back on with the original bolts just to get the flywheel and bellhousing indicated in. Yeah, I think I'll do that.

 

[db252]

@aleccolin
Never had an issue with the slave bolting up perfectly. My third Tremec install is completed and on the road and all have stock slave cylinders. Three different clutch setups and no issue.

You got lots going on there and keep the updates coming.

 

[aleccolin]

You're right, I don't know what I did or didn't do, but yesterday I was convinced it wouldn't work and today it pops right on. WTF, guess I was tired.

Thanks

 

[aleccolin]

So, the plot thickens...

I've been talking with Paul at Modern Driveline (good dude, knows his shit) and my best option is to stick with the Tilton HRB. Let me explain.

The OE master cylinder is a 3/4" bore and produces a full throw of approximately 7/16" with the OE slave/throwout bearing, matched to the range of actuation for the OE clutch, fully engaged to fully disengaged.

The ST-246 twin disc doesn't require as much throw to function, only about 1/4" to fully disengage. I will attest, having actuated the clutch on my shop press, I was surprised how little movement it took to release tension on the discs. Because of the compact nature of this clutch with the short stack height, Paul said there's a chance that the OE constant-contact throwout bearing could over-travel the ST-246 clutch, causing the fingers to touch the hub of the first disc. He recommended I fully reassemble the clutch to the flywheel on the bench and take some measurements, so I did. Sure enough, the distance between the back of the fingers and the hub face of the first disc is only about 0.024" more than 7/16". It should still work with the OE throwout (and obviously does based on what db has said), but the clutch takeup would be closer to the top of the pedal travel and and even if the fingers didn't contact the disc, you'd might be routinely over-actuating the clutch if you go to the floor every time like most people do.

So back to the 3/4" bore master. Tilton typically recommends a 7/8" bore master with the 6000 series HRB with a pedal stop set to limit over-travel. Maximum travel on the 6000 series HRB is 0.700". With the factory 3/4 clutch master, the amount of travel you get out of the 6000 HRB is about 3/8". The air gap is 1/8" so that's a little bit of takeup and then 1/4" operational travel. You can tune the takekup point little a bit by adjusting the air gap, but they recommend just sticking to the normal 1/8" gap to account for clutch disc wear over time. 3/8" travel is just over half of the maximum stroke for the 6000 series HRB, so there's no risk of overtravel or need for a pedal stop.

The only variable remaining is if there is enough adjustment in the threaded adapter to set the Tilton HRB to the right height. If not, MDL has spacers available. Based on some quick measurements I think it'll be good.

I'm looking for a good source for some split machine shims for the bellhousing should I need them to correct for parallelism. I need a 7/16" slot size. A set from McMaster is about $27 plus shipping, but I'd like to get them local. Fastenal has them starting at 5/8", I'd rather stick closer to the 10mm bolt diameter.

 

[aleccolin]

I'm also replacing the pilot bearing with a "high-load" pilot from FRPP, part number M-7600-C, which appears to be what the OE pilot bearing is in my 2016 GT. My guess is the standard pilot bearing M-7600-B is used in the V6? Whatever the case, at least it's not a downgrade, and even with low miles the pilot bearing is one of those always replace components.

 

[aleccolin]

@db252 did your MGW shifter come with this extra bag of hardware? Two grub screws, lock nuts and lock washers? No clue what these could be for.

 

[aleccolin]

Okay I think I found it, positive fore/aft stops for the gate? Sorry this thing didn’t come with any instructions, not sure if I should just set these for 3 & 4 and call it good or what

 

[aleccolin]

NVM the Magnum has internal positive stops, don’t need them on the shifter.

 

[erikkire18]

Just received my Tremec today from Modern Drive Line!! shipped in 2 days!! cant wait to drive it

 

[db252]

@db252 did your MGW shifter come with this extra bag of hardware? Two grub screws, lock nuts and lock washers? No clue what these could be for.

I don’t think I got that extra hardware at all. I feel like I would have remembered that and I’m sure I added nothing to the MGW. Looks like you figured it out.

 

[db252]

Just received my Tremec today from Modern Drive Line!! shipped in 2 days!! cant wait to drive it

Congrats and let us know how it goes or if any issues come up.

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