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Technical T5 swap for highway rpm

Discussion in 'The Hokey Ass Message Board' started by Mr.Falcon64, Mar 27, 2019.

  1. Hey everyone. I just was writing has anyone ever attempted a t5 swap into a late model 64 falcon. My reason being right now with my 1:1 high gear and 3.10:1 final drive and 24.2 inch tires I’m doing 3,000 to go 70 on the highway. I just personally don’t feel comfortable with that rpm for hours on end plus I’m losing a lot of fuel economy. I can’t go to much higher tires because I need the small tires for the acceleration (144 is so gutless it won’t pull big tires). So I was thinking a 5spd manual would boost fuel economy and performance with the extra gears for closer ratios. Has anyone ever done this for a falcon. What can I expect besides obvious clutch linkage and driveshaft and speedo cable.
     
  2. nickleone
    Joined: Jun 14, 2007
    Posts: 331

    nickleone
    Member

  3. Baumi
    Joined: Jan 28, 2003
    Posts: 2,737

    Baumi
    ALLIANCE MEMBER

    With a T5 you will end up at about a third less rpm in high gear than now, depending on what OD T5 you find. My guess is with about 2000 rpm at 70 mph you will be logging that gutless 144 sixxer so badly it will drink even more... small engines need rpm to make torque. The most efficient spot in its rpm curve is where the most torque is. On my 235 chevy this sweet spot is at about 2500-2800rpm. I have tried 3.08 gears instead of 3.55s and it drank like a seasoned sailor.
     
  4. Baumi
    Joined: Jan 28, 2003
    Posts: 2,737

    Baumi
    ALLIANCE MEMBER

    ....it cruised at 1800- 2000 rpm, which was way too low...
     
    Hnstray likes this.

  5. Hnstray
    Joined: Aug 23, 2009
    Posts: 11,967

    Hnstray
    ALLIANCE MEMBER
    from Quincy, IL

    Yes, the lack of engine power is the greater ‘problem’.......consider swapping in a 250 Ford six along with the 5 speed.
     
    Montana1 and firstinsteele like this.
  6. The 250 is essentially a stroked 200, so even a 170 or 200 is an improvement over the anemic 144. The 250 was offered in Monarchs & Granadas IIRC.
     
  7. whiskerz
    Joined: Jul 7, 2011
    Posts: 148

    whiskerz
    Member
    from Ga.

    I have to agree with the other guys a 200 or 250 would be a good swap option. The 250 is taller so it may run in to issues in that aspect.
     
  8. Consider a 5.0 with a T-5. Much better!
     
    Buddy Palumbo and ffr1222k like this.
  9. pkhammer
    Joined: Jan 28, 2012
    Posts: 602

    pkhammer
    Member

    I have a T5 front shift from Modern Driveline for sale. Unused. PM if interested.
     
    MIKE STEWART likes this.
  10. Buddy Palumbo
    Joined: Mar 30, 2008
    Posts: 3,870

    Buddy Palumbo
    Member

    I like this idea, LOL !
     
    Montana1 likes this.
  11. 200 swap is in the probable eventual plans. For right now then is 3,000 ok as long as temp and oil pressure are good? It’s only a 2.5 inch stroke. And as for the v8 I don’t have the $$$ to swap everything needed for a v8 plus I’ll keep the HO block for another build
     
  12. Baumi
    Joined: Jan 28, 2003
    Posts: 2,737

    Baumi
    ALLIANCE MEMBER

    3k is not very much for such a small engine. .. I had a 10.5: 1 cr 355 chevy with a healthy cam (234*/244*@.050) that had its sweet spot @ 3500 RPM. I put a lot of miles on that engine at 3-4 k or more. .. ... it was pretty good on gas if I stayed under 4500rpm / 110 mph. Like 14,5mpg. Cruising at 65mph I got about 20mpg. Fuel economy really depends on how well a setup is working together
     
    Hnstray likes this.
  13. Hnstray
    Joined: Aug 23, 2009
    Posts: 11,967

    Hnstray
    ALLIANCE MEMBER
    from Quincy, IL

    Over the decades most vehicles were geared in such a way that 3000 plus was common cruising rpm. Of course, engines were given shop overhauls (ring job and valve grind, maybe bearings) as early as 50,000 miles. But other contributing factors were less accurate production tolerances, metallurgy and lubricant quality and filtration.

    3000 on your short stroke 6 banger is not really much of a strain. Years ago I read about piston speed in terms of feet per minute. 2500 fpm was the suggested upper limit for longevity. Just ran the math on your 2.5” stroke.....if my reasoning was correct, your engine would have to turn 6000 rpm to reach 2500 fpm piston speed.
     
    norms30a likes this.
  14. seb fontana
    Joined: Sep 1, 2005
    Posts: 6,924

    seb fontana
    Member
    from ct

    A five speed with the .8/.83 fifth gear would be what you need for an rpm of around 2400 at 70 mph..T5 from a 4cyl mustang or bird would have the around .8 fifth gear and a 4.0 or so first gear so you'd get some snap off the start..It would be a Non World Class but if in decent condition to start with should hold up fine..If you get a World Class [v8-87 up] it will have a first of 3.35 so still a little better at the start but fifth will be .63/.68 and bring rpm at 70 down to around 1900 which would be a lug fest..You could change fifth gear to a .8 but the set costs around $270...
     
    Hnstray likes this.
  15. sdluck
    Joined: Sep 19, 2006
    Posts: 2,703

    sdluck
    Member

    Correct me but isn't that dist vacuum only,wouldn't a dist with mech and vacuum advance help it
     
  16. 2OLD2FAST
    Joined: Feb 3, 2010
    Posts: 3,230

    2OLD2FAST
    Member
    from illinois

    I don't know how well your 144 does on mileage , but consider this .,I had a long WB 79 ford e100 van with a 300 inch 6 ,c6 ,2.9 rear gear , used it to haul stuff up to my family's cottage , 700 miles round trip , if my wife drove , wed average 24 mpg , no OD no EFI , that 6 wasn't fast , but it ran 130k miles without a problem and would pull stumps while getting good gas mileage !!
     
  17. Thanks for the reply. That should be no problem seeing as even in neutral gear she doesn’t rev past 5K because of valve float. I guess it was my own superstition. I will hold on a 5spd until I get a 200 thanks for the info about lugging and gear ratios. Your right it’s a gutless turd but peak 90HP is at 3,400 rpm so 3,000 pretty close. Looks like it’s gonna be pedal down and gas station bound (I know it’s a butchered reference). Now the real problem controlling 70 mph with 1” slack in steering and then slowing down from 70. Definitely going to discs soon. I just hope manual disc brakes won’t be super hard to stop with
     
    Hnstray likes this.
  18. I run manual front discs on my '59 Ford and it stops well. I had a 3.56 rear in it and with the big cam, it lugged horribly around town, not good on engine bearings too. I had to run it in 3rd gear (4-speed) at 30 mph. Went to a 3.89 rear and it was like night and day. You can plug tranny gear ratios, tire sizes, rear end ratios into an online calculator and see what your RPM will be. With the 5-speed you can run a pretty steep rear like a 3.73 to 4.11 or so.
     
  19. Mike51Merc
    Joined: Dec 5, 2008
    Posts: 3,856

    Mike51Merc
    Member

    Manual discs (Granada style) on a Falcon stop just fine with little pedal effort.
    A T5 will also require a bellhousing adapter plate and modification of the crossmember.
     
  20. Blues4U
    Joined: Oct 1, 2015
    Posts: 5,493

    Blues4U
    Member
    from So Cal

    I was taught early on that engines don't like to be revved up to max rpm when unloaded, not a good practice. Save the max rpm's for when you're actually running down the road.
     
    seadog likes this.
  21. Oh of course your right I know it’s not best for it at all it was really dumb to do. I know it’s bad for bearings and stuff. Don’t plan on doing it again lol. Thanks for the help everyone. You’ll probably see more posts from me as time goes on and I work on it some more
     
    Blues4U likes this.

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