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Discussion Starter #1
Guys. New to the forums since I just picked up a beautiful 1965 Lemans. Pretty clean with no rust!

Previous owner swapped in a 350 SBC motor with MSD distributor and ignition and a B&M mini blower. I plan on installing the MSD Atomic kit soon to improve drivability.

It has ab3 speed auto tranny in it (TH350 maybe?) and it's boring as shit to drive. ? I'm looking to swap in a 4 speed or 5 speed, if possible.

Tremec T56's are readily available around here. Pedal assembly is easy to find. The bell housing, crossmember,flywheel, driveshaft, clutch and pressure plate can come from American Powertrain, since they sound like they can provide those easily.

My question is, has anyone done this? Some threads I've read suggested floorpan/ sheetmetal work is required. I really DON'T want to get into any sheetmetal work. I want a bolt-in installation.

Any other comments or suggestions are welcomed.

Thanks in advance!
 

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A Tremec swap will require tunnel modications. Doug Nash/ Richmond 5 speed can be installed w/o extensive tunnel mods. As the '65 has a SBC in it, an affordable bell housing, z bar, frametab, & pedals oughtto be avail locally. All will be same as early Malibu/Chevelle/Elco.. Your choice will basically be 10 1/2" clutch, flywheel, & matching bell housing or 11" clutch, flywheel, & bell housing. I'd prob go with the latter, so if any later engine upgrades, will already have an 11" clutch.
 

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Tunnel mods (extensive cutting) will be required. Have 3 customers with A-bodys ('65 & two '69's) that I've built performance rearends. Each installed Tremecs with the profiled cases to give more tunnel clearance. All had to hack up the trans tunnel & form pieces to close up the tunnel. 2nd Gen Birds & Camaros can get away without all the cutting, much taller bigger transmission tunnel. Have several friends that have done TKO swaps in their T/A's.

the Richmond 5 spd/ Doug Nash 5 speed Ive r/r'ed in a '70 GTO & a '78 T/A were the same size as a big output shaft ('71-74) Muncie . In a '70 GTO swap, had to have stock 4spd driveshaft shortened 5/8" to stock '71-72 GTO driveshaft length. Two of my 455HO cars have original M22's. have prev owned 3 others with M22's, one with a fresh big output shaft M21. having shifted many well setup Muncie 4spds, several DN 5 speeds & a few TKO's, I prefer the smoothness of a well shifted Muncie 4spd. Another irritating factor... with 500 -560ft lbs of torque, many of the Tremecs & most of the DN street 5 spd/Richmond 5 spds have an annoying low 3.27 1st gear. In the street DN 5 speeds, the 3.27 first gear is followed by a huge drop in ratio to 2nd gear. In the 90's a good friend swapped 3 different ratio rears in his '69 GTO which had a RAV headed 434 & street DN 5 spd. The 3.27 first gear was basically useless & his RAV combo basically lacked quite a bit of torque down low compared to other Pontiac builds .
 

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Discussion Starter #6
So the Muncie 4 speed would bolt right in? Are there any other manual transmissions that would not require no sheetmetal work? I'm open to other suggestions as well.
 

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following were used by GM in the 60's & '70's, all but the T-10's we're installed in GM A-body's.
all of the below fit, shifters & shifter linkage will differ for several styles.

- early Borg Warner T-10 4speed w GM input shaft
- early Muncie 4 spd w 7/8 cluster pin
- Saginaw 3spd, Saginaw 3spd w OD, Saginaw 4 spd
- Muncie 4spd w 1" pin, used through '70
- Ford toploader HD 3speed used by Pontiac '66-69
- '71-74 big output shaft Muncie 4spd
- 2nd design BW T-10, often mistakenly called a Super T-10

other direct fit transmissions that have been installed in GM 60's & 70's A & F, typically for drag racing

- BW Super T-10, the real deal, bought through '70's Speedshops, has high nickel gear set.
(small output shaft is common style)
- Nash 4 speed, basically an aftermarket Super T-10, high nickel gear set
- modified Chrysler 833...usually the Hemi ratio 4spd, has aftermarket input shaft.
chysler 833... require some shift porch mods, it's been 25 years since I've examined one.
 

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Got a quote for a complete 5 speed kit from American Powertrain for a Tremec TR600 complete kit for $5000! Man, that's steep! I mean, it's complete down to the pedal assembly and clutch but still...

Wish there was a way to get a 5 speed in for around $2k-3k...
 

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Got a quote for a complete 5 speed kit from American Powertrain for a Tremec TR600 complete kit for $5000! Man, that's steep! I mean, it's complete down to the pedal assembly and clutch but still...

Wish there was a way to get a 5 speed in for around $2k-3k...
What you want to pay and what it really costs are always 2 different things. A 5-speed, or even a 4-speed conversion is not inexpensive. Most 5-speed transmissions will start around $2300-$2400. Then you have to consider all the other parts to make it work. 5K for a turn key kit is not out of line.

The TKO is not one for spinning high RPM's in its factory form. I got the TKO-600 knowing it will not shift cleanly if at all, past 6,000 RPM's unless it is upgraded - which is more money. I don't plan on spinning my 455 past 5,800 RPM's so it fit my needs. Things may have changed since I purchased mine, so check if the TKO will shift cleanly at higher RPM's in factory form.

If you want to make your automatic less "boring," then put a manual shift kit in it.
 
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