Tremec TKO vs 3550

luke-44 · #1 (**permalink**) 08-30-2003, 10:22 AM

Hi Bob - I am building a 302 - 325/350 HP.

As I understand it, the 3550 is a bit less expensive, the TKO is more $$, but heavier duty.

Is the 3550 sufficient for my application?

I also understand the input shafts are different splined - the TKO using a 28 spline GM input and the 3550 using a Ford input shaft - I am unsure of the # of splines. Is this correct?

If so, how does the GM spline with a GM clutch disk mate up to a ford flywheel? Which pressure plate would you use with this combo with the TKO?

My motor came from an auto trans car. Can you confirm I would need this piece? -

http://cgi.ebay.com/ebaymotors/ws/eB...category=33733

Thanks in advance...luke-44

aumoore · #2 (**permalink**) 08-30-2003, 01:07 PM

The 3550 should be more tranny than your motor can throw at it. IMHO the TKO is not needed unless you are doing one of the following: using a strong Big Block, running a power adder like turbos, Supercharger or N2O, planning on a lot of drag strip duty using slicks. The TKO costs more and needs a special clutch setup. I have heard the TKO is a little harder to shift than a 3550.

I upgraded to a 3550 from a SD T-5 that did not like my mild 5.0. I called Forte's and they said for under 450 HP the 3550 is plenty.

If you go with either transmission get the McLeod bellhousing, the proper GM syncromesh and a pro 5.0 shifter. Both Tremec transmissions come with a shifter that most people say is junk.

luke-44 · #3 (**permalink**) 08-30-2003, 01:23 PM

Thanks for comments. Just to confirm , I would need this plate, right?

http://cgi.ebay.com/ebaymotors/ws/e...&category=33733

Also, would this style of bellhousing work with the 3550?

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2429774478

luke-44 · #4 (**permalink**) 08-30-2003, 01:28 PM

oops, I miised the full url. Should be -
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2429607247

aumoore · #5 (**permalink**) 08-30-2003, 02:17 PM

Yes they are goth required for a Tremec but I do recommend using a Scatershield like the McLoed if you plan to "play" in the Cobra. If you just plan on street driving and the occasional run thru the gears the aluminum bellhousing is ok but for any type of racing you need a scatershield or Kevlar Levis.

The reason being is in a Cobra the flywheel is parallel to the Calf of your leg and there is only a little fiberglass seperating it from you leg. Spend a little more and get a good Scatershield.

I ran a stock bell housing on my T-5 but I was always thinking of the potential of it taking my leg off so I would never do any speed shifting or droping of the clutch on take-off. Most Production cars are built so that the flywheel is ahead of your foot so the potential for disaster is not as great as in a Cobra.

aumoore · #6 (**permalink**) 08-30-2003, 02:21 PM

here is a good supplier of Tremec parts

http://www.fortesparts.com/tremec/index.html

NeedAntiVenom · #7 (**permalink**) 08-31-2003, 08:13 AM

Luke,

You should use a blowproof bellhousing, lakewood, etc. because of where the flywheel sits relative to the footboxes - a blown clutch or flywheel can be a disaster.

The belhousing may need to be trimmed on the bottom to fit the frame - if you haven't gotten a manual from Peter yet you should probably do that before gathering up parts - it has a lot of detailed parts information in it - including some parts modification info. Also, there is also a spacer required for the Tremec.

The 3550 is rated at 350 ft-lbs, the TKO is 425 ft-lbs. If you're using very sticky tires you might consider the TKO, but either should be plenty strong enough. I'm using the TKO, for my 320 HP 302, and a Lakewood - insurance in case I upgrade the motor at some point. A 3:54 rear is a nice match for a TKO.

Fifth gear is a very big jump (.68:1) on the 3550 and TKO - hard to pull at high speeds with a small block - but great for cruising (~1800 at highway speeds). The 3550-II and the TKO-II both have a .82:1 fifth as an alternative.

Best of Luck,
Jim