Tranny and rear end options for 427W stroker

[SMV]

Hi
I have a Ford Racing 427W long block M-6007-Z427FRT spec'd at 535 hp at 5,600 rpm, as well as 545 ft.-lbs. of torque at 4,500 rpm.
I am looking to put in a TKO 600 bout don't know which way I should go on the OD gear. Right now, I have a 3.73 geared rear end with 3-link. I live on an acreage and drive mostly 60-65 mph around the countryside, and make a couple of longer distance highway drives at higher speeds. Of course there will be some city driving. Rare, if any track days.

I've been told the 3.27 rear with .82 OD would be good for the engine. I'm concerned about excessive noise on longer trips and am leaning towards the .64OD to keep the noise down on the highway but don't want to lug the engine. I will try the 3.73 rear end as is and eventually swap out the gears to 3.27 or 3.55, if needed. Any thoughts? I know this topic has been asked many times but I want to make the right decision. Thanks
Steve

[stacked33]

Hi
I have a Ford Racing 427W long block M-6007-Z427FRT spec'd at 535 hp at 5,600 rpm, as well as 545 ft.-lbs. of torque at 4,500 rpm.
I am looking to put in a TKO 600 bout don't know which way I should go on the OD gear. Right now, I have a 3.73 geared rear end with 3-link. I live on an acreage and drive mostly 60-65 mph around the countryside, and make a couple of longer distance highway drives at higher speeds. Of course there will be some city driving. Rare, if any track days.
I've been told the 3.27 rear with .82 OD would be good for the engine. I'm concerned about excessive noise on longer trips and am leaning towards the .64OD to keep the noise down on the highway but don't want to lug the engine. I will try the 3.73 rear end as is and eventually swap out the gears to 3.27 or 3.55, if needed. Any thoughts? I know this topic has been asked many times but I want to make the right decision. Thanks
Steve

I have that exact long block and I put an OD automatic with .7 OD ratio and a 3.54 rear end ,and 26.5 tall tires in my 33 Hot Rod. Almost perfect, but if I could not control my converter lock up and hold it off until 65 MPH I would go with 3.73 rear. That motor doesn't like to run much under 2000 RPM. 70 MPH =2000 RPM.

Stacked33

[SMV]

I have that exact long block and I put an OD automatic with .7 OD ratio and a 3.54 rear end ,and 26.5 tall tires in my 33 Hot Rod. Almost perfect, but if I could not control my converter lock up and hold it off until 65 MPH I would go with 3.73 rear. That motor doesn't like to run much under 2000 RPM. 70 MPH =2000 RPM.

Stacked33

Which TKO OD gearing would you suggest (.64 or .82)? With the 3.73 gears, my understanding is that first gear would be useless, or burn rubber. I have the 17" Hallibrand rear wheel (~25.5") and a Mk4 roadster.

[Gordon Levy]

.64 if you don't plan on tracking it.

[stacked33]

Which TKO OD gearing would you suggest (.64 or .82)? With the 3.73 gears, my understanding is that first gear would be useless, or burn rubber. I have the 17" Hallibrand rear wheel (~25.5") and a Mk4 roadster.
Sent private message.

[CraigS]

Another way to approach this is try to figure out how happy your engine is at say 1500 in 5th. You can get a good idea w/ your current 373 but realize that a 331 will have you 1600 =55mph and 2000= 70mph. The 1600 at 55 is the downside of the .64 5th gear. W/ your hp and tq I could make a pretty good case for a 308 diff and the .82 5th. After analyzing all the numbers there is one more thing- that .64 5th makes for a rather unnatural feeling when you make the 4th to 5th shift- it's a big drop in rpm.

[pc12cvs]

Steve,

I have a similar motor (427W, ~538hp at sea level built by The Engine Factory), with 3.27 rear end, TKO 600 with the .64 OD gear (TCET 5008), ceramic headers from FFR and the stainless pipes from FFR. This observation is based purely on go-karting. I only recently put the body on. But even with the body off, and all the wind noise, I like the .64 OD for cruising. Ends up spinning around 1900 rpm doing 70mph, and it's quiet enough to hear my radio and talk to the person next to me. Does ok down around 55mph as well. No gear noise that I can tell, only wind and road noise. 5th gear obviously isn't as responsive as a downshift to 4th, but it still doesn't bog down when you accelerate in 5th (even up here at 4300ft MSL).

I'm building the car for running around town and road trip cruising, so I'm happy with the setup. If I catch the track bug later down the road, I'll reassess. That's my .02 based on my limited experience with the car so far.

Noel

[Takis31gk]

If you're interested in going as close to period correct as possible, Gforce Transmissions makes a T-5 that has similar torque ratings as the TKO's and has quite similar gear ratios as the original cars (2.42, 1.53, 1.23, 1.00, with options for 5th gear vs. 2.20, 1.66, 1.31, 1.00 in the original BW T-10). Combine this with 3.55's and you're nearly on point with the originals (3.54:1 rear end).