TKO 3550 swap to TKO 600

kvonbehren · #1 (**permalink**) 11-11-2017, 06:30 AM

I'm new to Club Cobra and this is my first time on the forum so please forgive if this question has been asked a million times.
I just bought an 01 Superformance Mark 111 which has motor issues (460). Rather than rebuilding the 460 I'm going with a 545 that makes about 700hpand 650+ torque. The car currently has a tremec tko 3550 and I'm thinking of switching to a tko 600 to handle the power and torque. My question is will the 600 be a direct replacement for the 3550? Actually nothing wrong with the 3550 just afraid it may not hold up. No racing just street use but I do like to hammer once in a while. Also I read where some guys recommend cutting the trans crossmember and installing a removable one, is this an option for the Mark111. Thanks

blykins · #2 (**permalink**) 11-11-2017, 07:53 AM

It will require a different clutch disc, but will be a direct replacement.

I'd swap too if you're looking at that much power.

Mark IV · #3 (**permalink**) 11-11-2017, 08:26 AM

Do not cut the crossmember.

Remove the seats and the tunnel for unhindered access. It is easy to pull/install the engine and trans as a unit with the front of the car raised but if you want to split them, having the tunnel out makes it easy.

8 nuts for the seats and 12 or so screws for the tunnel. You will need to work a putty knife in the tunnel to floor joint to release the sealant. Cover the carpets before you do, it is messy, but once done you have easy access to the trans.

kvonbehren · #4 (**permalink**) 11-11-2017, 10:46 AM

Excellent Thanks for the help. One additional comment my trans is the model 2600708 tko 3550 2 which I read has a 26 spline input shaft. It should take the same clutch as the 600, correct? Would you recommend the .64 or the .82 fifth gear. Any idea where I can find a replacement dust boot that attaches to the top of the shifter box. on the 3550. I see the newer style but can't find the one I have. Getting it ready to sell.

blykins · #5 (**permalink**) 11-11-2017, 11:36 AM

If you're pushing for that much horsepower, the cam will pretty much necessitate that it be an .82 overdrive. Otherwise you can put the engine into a cruise rpm where it will buck.

Turret dust boots are no longer available from Tremec.

I'm a Tremec dealer, would be glad to help you out.

kvonbehren · #6 (**permalink**) 11-11-2017, 02:51 PM

Thanks. Could you get me a price on tko 600 with the .82 overdrive. As for the 3550 it has 17k miles is it worth anything. I can call you next week if we should discuss over the phone

blykins · #7 (**permalink**) 11-11-2017, 02:53 PM

Tremec works off of a minimum advertised pricing program. Every vender that sells a TKO 600 should sell them for $2450.

Shootnride · #8 (**permalink**) 11-12-2017, 06:52 AM

Quote:

Originally Posted by kvonbehren

Any idea where I can find a replacement dust boot that attaches to the top of the shifter box. on the 3550. I see the newer style but can't find the one I have. Getting it ready to sell.

I bought one from Joe Forte a few months ago. At that time he said he had quite a few of them.

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Ted

olddog · #9 (**permalink**) 11-12-2017, 08:12 AM

You have been given good advice. Go with the.82 5th or you will kick yourself every time you drive it.

I was told by a factory rep at a car show that the 3550 rebuild PDF that was online at the time works for the TKO 600 too. He said the case is almost the same. The TKO has stronger internals, but the design is very similar.

kvonbehren · #10 (**permalink**) 11-12-2017, 10:04 AM

Thanks for the guidance.

hinoonaz · #11 (**permalink**) 11-15-2017, 02:47 PM

I might be in the market . What HP rating is the 3550. Mine is350 at the wheels. Currently a T-5 beefed up.

olddog · #12 (**permalink**) 11-16-2017, 06:59 AM

They make the TKO 500 and the TKO 600. Those are rated 500 ft-lb and 600 ft-lb of torque respectively. Since the 3550 went into factory cars that made over 300 ft-lb of torque, I would guess it is good to 400 ft-lb.

Torque is what breaks parts. The RPM is not as important, unless you are concerned with oil temp. Cars spend little time a high hp, so torque is the important number.

Doggone · #13 (**permalink**) 11-16-2017, 07:33 AM

The 3550 is rated at 425 ft-lb

kvonbehren · #14 (**permalink**) 11-17-2017, 07:04 AM

hinoonaz
The torque rating for 3550 is 425Ft/lbs as Doggone states. My 3550 is the later one that has a 26 spline input/31 spline output shaft. I believe the early ones had a weaker input. I think I have a friend that has a terminator Cobra that wants this trans. If that deal falls through I will gladly let you know. Either way I will want to sell it.