5 speed upgrade

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   hi, this winters project will be a drivetrain restification of my 77 Hornet AMX. Currently it's a 258/2bbl, 4 speed SR-4, with 2:73 open diff. Car runs and drives well, but...you know...can't leave well enough alone:)I would like to upgrade to a five speed trans. Choices are: WC T-5, or, Tremec TKO 500.
I am KEEPING the 258, though it will be "restified." I LIKE 258s! Shooting for 150-175 hp. Streetable.
I understand that the Tremec TKO is overkill for a 258, and about twice as expensive, but I found a used one locally for about the same price as a rebuilt T5. 
Question: does the TKO require trans tunnel modification?, I believe the T5 does not.
I do NOT want to cut up the car, so this will be the deciding factor for me.
Question: I understand that any 5 speed swap will need better gears, does 3:55 sound OK? w/.68 overdrive? and... who does good rear axle rebuilds? Axle is the stock AMC 15. thanks, gz

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amcfool1 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jun/18/2011 Location: roanoke va Status: Offline Points: 1075	Post Options Post Reply Quote amcfool1 Report Post Thanks(0) Quote Reply Topic: 5 speed upgrade Posted: Sep/17/2016 at 1:22pm
	hi, this winters project will be a drivetrain restification of my 77 Hornet AMX. Currently it's a 258/2bbl, 4 speed SR-4, with 2:73 open diff. Car runs and drives well, but...you know...can't leave well enough alone:) I would like to upgrade to a five speed trans. Choices are: WC T-5, or, Tremec TKO 500. I am KEEPING the 258, though it will be "restified." I LIKE 258s! Shooting for 150-175 hp. Streetable. I understand that the Tremec TKO is overkill for a 258, and about twice as expensive, but I found a used one locally for about the same price as a rebuilt T5. Question: does the TKO require trans tunnel modification?, I believe the T5 does not. I do NOT want to cut up the car, so this will be the deciding factor for me. Question: I understand that any 5 speed swap will need better gears, does 3:55 sound OK? w/.68 overdrive? and... who does good rear axle rebuilds? Axle is the stock AMC 15. thanks, gz
	george z

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Sep/17/2016 at 4:32pm
	Glad to see someone else wanting to keep an I6! I'd go with the T5. It'll fit right in and you already have the correct bellhousing for it. The TKO will require a bellhousing change, unless I'm mistaken... I'm not sure about the overall design of the SR4, but, if it's close to the T5 you won't have to relocate the shifter. If it's nearly the same length (again, don't know much about the SR4) then you won't have to touch the driveshaft's length; although, you may have to get the slip yoke to fit in the trans (Summit). Also, I have heard from several people that say the TKO shifts like a "truck trans". Don't know how true that is. The T5 is known to shift well and your 258 isn't going to kill it. As to gears, I'd go no deeper then the 3.55. A stock T5 uses a 3.34:1 first gear and has a big leap to a 1.99 second. First gear will be super, super short with a 3.55. I'd shoot for something in the 3.31 range. First gear will be more usable then the 3.55 and your cruising rpm at 60mph will be around 1800rpm, depending on tire size. I've got a 3.31 behind a T5 bolted to my Javelin's 232, and, according to my gearing calculator, will turn 1880rpm at 60mph with the 25" tires I have on it. You're other option for a rear would be to install a Ford 8.8 unit. Look around an you might find one with a posi unit and the gear ratio that'll suit your needs.

amcfool1 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jun/18/2011 Location: roanoke va Status: Offline Points: 1075	Post Options Post Reply Quote amcfool1 Report Post Thanks(0) Quote Reply Posted: Sep/17/2016 at 7:59pm
	hi, thanks for your response. I have looked at gearing options. Seems like the 3:07 is available, then the 3:55. If you know of a place that sells a 3:31, let me know. Oh, yeah! I love my 258s. Just spent countless, I mean countless, (in that I'm afraid to count up all the receipts, over 3 lbs! of receipts) for my latest car. 84 Eagle 4dr Sedan, with, (not so stock) anymore 258. If I can ever figure out how to work a computer properly, I will post a couple pics. thanks again, gz
	george z

DaemonForce Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/05/2012 Location: Olympia, WA Status: Offline Points: 1070	Post Options Post Reply Quote DaemonForce Report Post Thanks(0) Quote Reply Posted: Sep/18/2016 at 3:25am
	I'm doing a 285(Exotic overbuild)with a T-5 and future NP229 swap. I still have odds and ends with the clutch pedal and brake system eating most of my planning. The shift action on the T-5 feels a bit clunky but natural and I haven't even fired it all up yet. Would a Hurst shifter smooth out this dissonant feeling of mid-quality action?

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Sep/18/2016 at 8:06am
	I think a lot of that "clunky" feeling comes from the stock shifter itself. I've gotten to drive my Javelin down my road and back (gas can strapped to fender, haha) and the shifts themselves are nice. I have a friend that really likes his Fox body Mustangs and one thing he swears by is the Pro 5.0 shifter. It has a positive stop and is a "tighter" unit with a shorter throw.

DaemonForce Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/05/2012 Location: Olympia, WA Status: Offline Points: 1070	Post Options Post Reply Quote DaemonForce Report Post Thanks(0) Quote Reply Posted: Sep/18/2016 at 12:47pm
	It looks like those of us with decent options for swapping shifters have a base with the 4 bolt pattern. I have the 5 bolt pattern. Looks like Hurst is going to be the only viable option for a different feel.

amcfool1 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jun/18/2011 Location: roanoke va Status: Offline Points: 1075	Post Options Post Reply Quote amcfool1 Report Post Thanks(0) Quote Reply Posted: Sep/18/2016 at 1:07pm
	hey Mr. 232jav, where in VA are you? i'm in Roanoke. gz, and where can i get 3:31 gears?
	george z

amcfool1 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jun/18/2011 Location: roanoke va Status: Offline Points: 1075	Post Options Post Reply Quote amcfool1 Report Post Thanks(0) Quote Reply Posted: Sep/18/2016 at 1:09pm
	again, Does the TKO need tunnel modification? Looks like I'll go with T5, just want to be sure, thanks, gz
	george z

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Sep/18/2016 at 3:50pm
	I'm in Keysville, Va. and work in Farmville. I've not seen a TKO in person, but it does look taller and wider then a T5. I would suspect it would be a tight fit without modifying the trans tunnel. Galvin's lists a 3.31 for the AMC 15 (looked it up under a '69 Rambler) and it's listed for an astonishing $435! I'd put a wanted add out there on the forum to see what other's have. I have a 3.08 on the floor if that would interest you. Would be better then what you have. Again, you probably have the option of using a Ford 8.8. I would suspect it would require the same modifications to fit your car as it would for use in an American. Maybe someone would chime in on that... Edited by 232jav3sp - Sep/18/2016 at 3:55pm

scott Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/10/2007 Location: Wildwood Pa. Status: Offline Points: 3502	Post Options Post Reply Quote scott Report Post Thanks(0) Quote Reply Posted: Sep/18/2016 at 4:55pm
	I've seen one TKO installation in an American. They lopped off the entire top of the transmission tunnel to make it fit & fabbed a new one. The guy that owned it told me he probably went a little overboard, but not my much. I've tried a few different shifters on my T5 Z. It was new when I installed it a few years back. The factory shifter is OK, but looked like it would wear & become sloppy. I ended up with a Hurst Billet Plus, seems like a decent shifter. The big thing that improved feel for me was the shifter lever. I started with the short one that came with the Hurst. It was only a couple of inches to move from gear to gear, super short throws, but the feel was horrible. No leverage due to the short handle made for high effort & a really notchy feel. A longer lever made for longer throws but a much better feel.