What Is The Best Manual Transmission for a 455 TH400 Conversion???

Discussion in 'U-shift em' started by haganlee, Jan 20, 2016.

  1. knucklebusted

    knucklebusted Well-Known Member

    Indeed, my car at 3500 in OD locked up would get me locked up at 107 MPH!
  2. oldsmobiledave

    oldsmobiledave Well-Known Member

    I agree. Have the same in my 65 442 behind a mild 455. I run mine with a 2.73 12 bolt posi.
  3. wkillgs

    wkillgs Gold Level Contributor

    I've got two of them, one in my Special with 300 and 2.79 rear, the other in a GS with 2.93 rear.
    Wish it had a wider ratio spread, The close ratio means shifting often.

    They are a good value, used ones can be found in the $1500 range.
  4. Dadrider

    Dadrider Silver Level contributor

    Did the Doug Nash/Richmond require any tunnel modifications? I would expect a crossmember relocate and driveshaft length change, Was there much more than that?

    When I was a teenager Borg Warner with a gearset for the Super T-10, they called it a Ultra Low gear set with a first gear of 3.44 : 1, and 4th being 1 :1 It was marketed for cars with the 2.5 to 3.08 axle ratios, to emulate a " 3:90 to 4.10 with a 3 speed" with 4th gear being, well like a over drive in a sense. It was tested in either Hotrod or Popular Hotrodding in a Big Block Corvette, with the drive test going pretty well. Has anyone ever heard of or used a Super T-10 built out like that?

  5. stickshift

    stickshift Silver Level contributor

    No tunnel mods needed. It has been so long I don't remember if the driveshaft needed any modification.
  6. boe

    boe Well-Known Member

    R.O.D. is nice with 2.73 2-series 12-bolt. But for how often or not) I drive the convertible on the interstate, I'd be happy with the 5-sp richmond/nash.

    NOTNSS Gold Level Contributor


    Did mine a couple years ago with pedal, bell housing, shifter, etc. from Dave Kleiner. Jim Goodlad at Hurst in San Diego has been great to work with as well as one of their authorized dealers in Caldwell, ID.. Modern Driveline.

    Trans has been flawless except for 2 self-inflicted problems. First was warrantied even though it was human error caused and the second was a couple years out of warranty but handled very professionally and quickly by the Idaho dealer. In fact, the trans will arrive back tomorrow. A buddy went from 5th - N - R looking to downshift to 4th (old school 4spd guy) at 90+mph. Minimal damage and only $50 in parts and $300ish labor.

    Love the 5spd. There are a few pictures of the tunnel mods on my car somewhere in here. A bit of a writeup there but interest in what we had to say seemed low at the time so quit posting it. Not that big a deal when you get the right parts from Hurst. The 70 car used the tunnel same as 67 chevelle BTW.

    Here's the thread: http://www.v8buick.com/showthread.php?219185-Keisler-Tremec-RS600&highlight=hurst+drivelines

    I should have taken pics of the tunnel when finished. Looks really good as a matter of fact.
    Last edited: Feb 29, 2016
  8. 69GS430/TKX

    69GS430/TKX Silver Level contributor

    Gary, thanks for the info on Hurst and their Tremecs. It will help me decide what to buy to replace my Muncie. I was close to buying a Keisler when they went under, and now I have another option.

    STAGE III Lost Experimental Block. Platinum Member.

    So is the general consensus that the Richmond 5 speed would be best (other than the Muncie with gear vendors) for the least amount of additional modifications,lower rpm's and price?

    Anyone know the model of the Doug Nash to look for?

    Mine has a M-20 currently in it but the floor was hack jobbed. Will the consolette work with the Doug Nash? Went through too much not to get to use that:3gears:
  10. 70 gsconvt

    70 gsconvt Silver Level contributor

    While I like rowing the gears as much as anyone, I did put a 200-4R trans in my car. Total for one that will live behind a stout 455 will be @$3500-4000 for everything including converter, TV cable, trans, driveshaft work, etc.

    I did do a thread on the installation with pics of the entire process. Good luck.

    STAGE III Lost Experimental Block. Platinum Member.

    Sounds nice Phillip, had one of those too but going after the man pedal on this one.

    So is the Richmond 5 speed the best option other than the Muncie for least modifications needed?
  12. staged70

    staged70 RIP

    Why not just run the Muncie Who needs a 455 that lumbers along at low rpms thats why we all have extra engines stashed away:) If you plan on a long road trip just get a set of 15X7 cheapies and put on a 215-75-15 that way you can run your 373 or 342 gears and still cruise. I remember a fellow at BG one year in a restored 70 stage car with a bit more compression and he drove the car like 800 miles to get there, His rear tires looked silly but it kept the rpms to a manageable level. Then he swapped on some low profiles and ripped up the strip
    If your buying all new parts then a richmond with a .87 5th gear would be a welcome addition

    STAGE III Lost Experimental Block. Platinum Member.

    I am glad you brought that angle up John. Seems like forever since I had my non a/c 3:64 posi M-21 Muncie Stage 1. Come to think of it that is exactly what I did on road trips to GS Nats and all.Real tall tires for the trip and normal one's in the trunk (and back seat).

    With the plans for this car I am going to still need to ultimately get this M-20 out of it though and of course the stinkin single track. For the cost of a Doug Nash I could probably get a rebuilt M-21 AND a complete posi rear though. Time for another wanted ad! Lol Thank ya Sir:TU:
  14. NOTNSS

    NOTNSS Gold Level Contributor


    The little bit I looked it seems the Richmond is no less money than the Tremec. Also Richmond I see in the above article is 1.0 5th gear so why bother if no OD? IMO the mods for the Tremec are not that big a deal and un-noticible when finished and carpeted. Torque ratings are equal. If you really want OD (I did) then go for it! Hard to beat 80mph at low rpm when you cruise the wide open spaces in the West.
  15. 69GS430/TKX

    69GS430/TKX Silver Level contributor

    That is my thinking as well. I don't enjoy my engine RPM at 3300 for hundreds of highway miles. Overdrive can pay for itself in gas savings and longer engine life. I spent too much time and money and patience rebuilding my engine. I don't want to ever have to take it out and tear it apart again.
  16. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    I've driven my Buick with 3.42 and 3.89 gears practically across the country and back a few times with a TKO-600 with cruising rpms between 2300-2600 depending on gear and speed limit (80mph through Utah and Wyoming). Probably have over 100,000 miles on it by now and three completed Drag Weeks.

    The Richmond would probably cruise about the same with ~2.73 gears and a 28"+ tall tire. To me, putting in any gears higher than 3.08 behind the Richmond is just extra shifting and expense over a 4-spd unless you are seriously drag racing.
  17. boe

    boe Well-Known Member


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