New TKO 600 install clutch questions

[igozumn]

Posted this on moparts, but figured I'd ask here too.  So, I'm thinking about pulling the trigger on a TKO 600 setup, probably from Silver Sport Transmission. Their initial bid/quote included a basic organic replacement 11" disc to fit the Tremec. I've had an 11" Centerforce Dual Friction in the car (69 Charger) for 15+ years that I've been pretty happy with. I don't race the car, just a street machine. My current flywheel is a resurfaced original from Brewers that I put in along with the clutch way back when. I'd thought I would just replace everything, including the bellhousing if I was swapping transmissions. I'm betting the stock style aluminum bellhousing they have is the same one everyone else has. I.e. Brewers, American Powertrain, etc.

So, I have a couple questions on clutches and mechanical vs. hydraulic.

Since the flywheel would need resurfacing to go along with the new disc, the pressure plate should be replaced too. And I would just get a new flywheel, so it's all new stuff.

Should I stick with the Centerforce Dual Friction line of product, or is there something else that is better, or go with stock/organic, or ?  Going to try and call Silver Sport this week, but have been absolutely buried at work. I stumbled upon their clutch listings and it appears they have a dual friction clutch available. Want to ask them about the clutch options and the carbon upgrades.


The initial quote/bid is to go with stock mechanical, but there is a hydraulic option. I do like the idea of the hydraulic operation pushing the throwout bearing straight out, vs the lever action of the stock fork.

Anybody running either the stock fork/pivot or the hydraulic?  I was going to get a new fork and fork pivot, since all my current stuff is pieced together from who knows what and I actually made the pivot I've been running for the last 25 years, LOL. Once I started adding additional parts, I thought I should just give consideration to the hydraulic setup. I don't have headers installed, but have them at the ready whenever I get around to buying new heads. Not having to mess around with the mechanical linkage (and body flex/driveline movent issues) would be cured with the hydraulic setup also.


Oh, should I go ahead and spring for the carbon syncros? Again, not a race car. Shifting rarely hit's 6,000, but wondering if that isn't something that I should just invest in.

Car is currently running 3.91 with N50 27-28"tall tires. I'm thinking I want the .64 overdrive for quiet-er freeway hustle-ing.

Just kind of asking for general feedback. Free shipping until the end of the month, but not in any real hurry either.

[INTMD8]

I have a TKO600 with hydraulic clutch. Definitely recommend that (hydraulic). Pedal feel is perfect.

My trans has the .64 overdrive.  Would much prefer the .82 myself. As it is, feels like driving a 6 speed with a missing 5th gear.  (too much rpm drop 4th to 5th).

Just my opinion.  Not sure on the rest.

[igozumn]

What rear axle ratio are you running?  

[Challenger340]

How much Camshaft size-wise(Lift and .050 duration), and cruise rpm are you targeting ?
just say'in...
any Engine running a Camshaft that still makes power up around 6,000 rpm ? may not much like 1,800-2,000 rpm, let be very efficient down there ?

remember,
ALL Cam manufacturers LIE through their teeth when it comes to rpm ranges for their Cams ?
just because the "book" says 3,000-6,000 rpm range for a Cam, they are usually all done by 5,000-5,200 rpm and well into the downside of the power curve, meaning:
1.) why are you shifting even rarely at 6,000 rpm
and,
2.) how efficient do you believe the engine will be at 1,800 rpm ?  (What cam ?)

[Mike DC]

I have a TKO600 with hydraulic clutch. Definitely recommend that (hydraulic). Pedal feel is perfect.

My trans has the .64 overdrive.  Would much prefer the .82 myself. As it is, feels like driving a 6 speed with a missing 5th gear.  (too much rpm drop 4th to 5th).

Just my opinion.  Not sure on the rest

Not long ago I talked to Liberty's Gears (a trans shop in Michigan) about the feasibility of custom-making an overdrive ratio for a TKO.  They said they had done it before.  IIRC they said it would run around $1000 installed (but that was not a firm quote).

I was thinking of something in the range of 0.75.

[c00nhunterjoe]

If i were to pay the money to go with an overdrive, i would get the steepest gear possible, the .64 and then run more rear gear to fit the package.

[igozumn]

How much Camshaft size-wise(Lift and .050 duration), and cruise rpm are you targeting ?  One cam below the .509/292.....it specs at .484 & .241 @ .050.  2100-ish at 65-70 mph
just say'in...
any Engine running a Camshaft that still makes power up around 6,000 rpm ? may not much like 1,800-2,000 rpm, let be very efficient down there ?

remember,
ALL Cam manufacturers LIE through their teeth when it comes to rpm ranges for their Cams ?
just because the "book" says 3,000-6,000 rpm range for a Cam, they are usually all done by 5,000-5,200 rpm and well into the downside of the power curve, meaning:
1.) why are you shifting even rarely at 6,000 rpm  When I had the .509/.292 cam in it, it pulled hard to 6k.  When I put the smaller cam in, it lost the top end. It's now mostly done by 5500, hence, rarely shifting at 6k.
6K seems to be the magic line where the Tremec has issues with shifting.  I may put a bigger cam and/or stroker engine in at some point, and wondering if I should just go ahead and upgrade to the carbon syncro blockers in.
and,
2.) how efficient do you believe the engine will be at 1,800 rpm ?  (What cam ?)  I have no intention of cruising down the highway at only 1800 rpm, lol. 

[igozumn]

The main reason for going with the .64 is for future highway cruising with the A/C on while running current legal interstate (75mph+) speeds.  The first 4 gears would work around town, just as the 833 has for 25 years.  I'm not concerned about equal spacing between all 5 gears.  Or, not concerned today, LOL. 

[XH29N0G]

I'm running the 0.64 and 4.30 rear 5th is nice at 70.  Using online calculators of RPM vs tire and rear, I think a 3.91 would also work in my case.  A lot depends on where the engine smooths out. 

I am using a mechanical dual friction centerforce and have no complaints.  I have been using it for about 8K miles so it is relatively new.  Pedal travel is basically the same as the original. 

I have no experience with hydraulic clutch cannot comment on pedal feel.  I have no experience with other clutches. 

I have not pounded on the car, but have run at the track in the low 13 range (someone who could drive better would be in the 12s) running 255 M/T street ET.  I include to give an idea of the set up.

Please keep us posted on what you find out and your experience with your choice.

[Mike DC]

  
The "shorter" overdrive ratios work better with the (wide ratio) TKO-500. 

The first couple gears in that tranny are so low that you can keep the axle gears pretty moderate.  (Comparing 1st gear ratios:  TKO-500 with a 3.55 rearend = stock 4spd with a 4.30 rearend.  How low do you really want the 1st gear to be?) 

When the axle gear is moderate then the 4th gear is still moderately high.  That setup isn't asking for a super-high 5th overdrive.

 

[Mike DC]

  
BTW, Tremec has an easy/convenient online calculator for their tranny options:


http://www.tremec.com/calculadora.php

[igozumn]

I'm running the 0.64 and 4.30 rear 5th is nice at 70.  Using online calculators of RPM vs tire and rear, I think a 3.91 would also work in my case.  A lot depends on where the engine smooths out.  

I am using a mechanical dual friction centerforce and have no complaints.  I have been using it for about 8K miles so it is relatively new.  Pedal travel is basically the same as the original.  Are you still running the overcenter spring?  I am and my friend's '70 Bee with the same clutch is also.  I do like the idea of having basically the exact same clutch feel, as I have come to like the way mine is set up.  Going hydraulic, I know would change that.  I do worry just a tad about firewall flex with hydraulic, but I guess it's not something to worry about.  Decisions, decisions....  

Please keep us posted on what you find out and your experience with your choice.  Will do!

Thanks to everyone for the feedback so far.   I appreciate all of it.  I've been playing around with all the ratios for about 2 weeks now.  Checking out the 3.91 vs. my old 3.55 and the .64 vs. the .82 and highway speed vs. take-off speed.  If I was running my old 3.55 (which I could put back in), I'd probably be leaning towards the .82.  But with my 3" Flowmasters and 3.91, I'm still thinking I would be happier with the .64 for highway driving.

[Mike DC]

 

The 0.82 overdrive would get along with a 3.23 or a 2.94* gear.  

3.91 with a 0.82 overdrive?  No way.  You're gonna wish you had gotten a 0.68 overdrive with that rearend gear.

The Gear Vendors overdrives are 0.78 ratio.  Plenty of guys combine those with rearends like 3.55 or 4.10 and end up disappointed that the GV didn't bring down the revs enough.



* Yes, I would still like an overdrive gear with a 2.94 axle.  The OEMs all would.  

Muscle car guys have funny ideas about what is tolerable cruising revs.  You hear discussions about "RPM @ 60 mph" - WTF?  In many places the AVERAGE traffic speed is nearly 80 these days.  The minivans & Corollas are going that fast.

[igozumn]

3.91 with a 0.82 overdrive?  No way.  You're gonna wish you had gotten a 0.68 overdrive with that rearend gear.

Muscle car guys have funny ideas about what is tolerable cruising revs.  You hear discussions about "RPM @ 60 mph" - WTF?  In many places the AVERAGE traffic speed is nearly 80 these days.  The minivans & Corollas are going that fast.[/i]

Just got off the phone with a friend of mine.  Told him the same thing, but worded it differently.  I'm not going to spend $6000 to only drop my RPMs down to 2500, LOL.


I have a couple friends that run to one or two of the shows we bring the cars to, that can't maintain 55mph.  Absolutely maddening having to wait for them.  No excuse in this day and age to not be able to run 70.

[XH29N0G]

I run the overcenter spring.   

Since I haven't tried the hydraulic, I don't know if I would notice the difference between hydraulic and mechanical.  If the hydraulic is like the clutches in other cars I have driven (mostly European cars) then yes I would notice a difference.  I might prefer the change, BUT since I have never driven one, I am not a good gauge for knowing whether there is a difference. 

Can anyone else give a more detailed description of the difference in feel, pedal travel, etc.... between hydraulic and mechanical linkages?

[John_Kunkel]

I am using a mechanical dual friction centerforce and have no complaints.  I have been using it for about 8K miles so it is relatively new.    I've been playing around with all the ratios for about 2 weeks now.  Checking out the 3.91 vs. my old 3.55 and the .64 vs. the .82 and highway speed vs. take-off speed.  If I was running my old 3.55 (which I could put back in), I'd probably be leaning towards the .82.  But with my 3" Flowmasters and 3.91, I'm still thinking I would be happier with the .64 for highway driving.

I'm running the .64 Tremec with 3.55 gears in my '56 Plymouth. The 360 LA has a choppy cam of unknown specs and it rolls out from a stop easily in normal driving. I went with an external slave for the hydraulic clutch, heard too many stories of the hydraulic TO bearing leaking.

[igozumn]

Well, took a big plunge today.  .64 5th, Silver Sport Dual friction, carbon syncro blocker upgrade and hydraulic setup.  Should ship out tomorrow or Friday.  

[Lennard]

Well, took a big plunge today.  .62 5th, Silver Sport Dual friction, carbon syncro blocker upgrade and hydraulic setup.  Should ship out tomorrow or Friday. 

You mean... your bank account took a big plunge today.

[igozumn]

Yes.  That too!

[igozumn]

Ordered Wednesday. 

Shipped out today (Friday).

Scheduled delivery for Tuesday.


That's.........quick.

[Rolling_Thunder]

Congrats on the purchase - I ran a TKO trans in my 68 before I swapped to a T-56

I had the older style - 3.27 first gear and .68 5th gear...    was quite fun - I ended up running 3.55's with a 28" tall tire - 1st gear was pretty short and it was cruising at 1900rpm at 65mph...      now I'm running 3.91s and at 64mph I'm only turning 1500rpm with the T-56