["Guy]

Has anybody swapped out a 5spd tremec tranny in a 4spd muncie '68 gto car? What does it take to do this? and what "used" tremec tranny holds the most torque, which do recomend?
Where would be a good place to buy a tremec in Mlps,mn?
Guy

["Guy]

Has anybody swapped out a 5spd tremec tranny in a 4spd muncie '68 gto car? What does it take to do this? and what "used" tremec tranny holds the most torque, which do recomend?
Where would be a good place to buy a tremec in Mlps,mn?
Guy

["Guy]

bump.

[BanditT/A]

I have found this on 5speedtransmissions.com in the A-body category. Although they only show a conversion on a 69 chevelle, it should be similar since it is an A-body between '68-'72

Here it is:

http://www.chevelles.com/techref/web...tallation.html

[matrix]

Im about to do the swap on my 70 gto. My car is an auto so it is a lot more involved than yours. You need a Tremec trans that is specific for the conversion. There are several available with different ratios and torque ratings. The trans will bolt right up in place of the muncie. You will need to change the clutch disc to a 26 spline unit if you currently have the 10 spline. 95% chance you will have to cut the trans tunnel and use a piece of sheetmetal to cover the hole. Ding the crossmember for clearance and move it rearward 1.8 inches and drill a couple new holes. Shorten driveshaft approx 1.5 inches and install new yoke. Away you go. I got the best price on my trans at a local speed shop. If yu dont mind spending a little cash Keisler auto has kits with the driveshaft,crossmember,sheetmtal for tunnel,etc so it is really abolt in. Depends on how much fiddling, cutting and hammering you want to do yourself.

[GS470]

Like matrix, I converted from an auto to a 5spd. He covered most of the issues I ran into including having to cut the top off the tunnel.


Besides having to cut the tunnel, my biggest challenges were finding the all the clutch linkage parts and then getting the clutch linkage adjusted properly. What a PITA, but I think my Lakewood scattershield was the primary problem there.

I bought my TKO II from Eric at Swarr Auto. They sell "kits" for GM installs and their prices seem to be competitive. The TKO II was the strongest 5spd available at the time, the TKO-500 and TKO-600 weren't out yet.

I wasn't aware of Keisler when I did my conversion and it does look like they offer some nice packages. They also offer hydraulic clutch kits. I don't know what the price tag is, but I'd love to convert to a hydraulic clutch some day.

There probably isn't much for you to look at, but since we're practically neighbors, you're certainly welcome to look at how things are installed in my car if you're interested.

["Guy]

GS470. I'm intrested. Please give me a call @763-422-2324. My car is a 4spd so I don't think i'll have cut the car up to much. I saw Keisler kits with the TKO with a 3:55 gear 26.5 tire...4:60 1st gear ratio, 2500rpm 83mph. My cam just starting to run @2500rpm...5800rpm in fifth would make State tropper Air patrol in Lake City rub their eyes in disbelieve.
I was thinkin old school route...John's Auto for that tranny?
Guy

[ed boersma]

GS470 I'm up in Fridley and would appreciate the chance to look your car over. I'm restoring a '72 GTO that I ordered new from Brookdale Pontiac. Transmission alternatives are of interest. My phone is 763-586-0700. Thanks!

[Tom McQueen]

Im doing this right now on my 70 GTO. Havent cut the floor yet, but thats the next step. You will need the 2" left offset shifter if you want the stick to come thru the factory console. I will post some pics of this shifter next weekend.

[6t7gto]

gs470,
what are the two switches beside your cigarette lighter for?
i just replaced my 70 lemans dash and there was a rear defroster switch there. i don't have it and was thinking of putting my nitrous switch in that slot.
what kind of switches are they?
part number?
thanks,
david

[6t7gto]

i have a 6 speed in my 70 lemans and my floor is cut up no where near as much as the one in the pic.
i did refab my rear tranny crossmember.
i lowered it 1 1/2 inches where the trans mount is located.
i also have the hydraulic clutch assembly.
nice neat install.
david

[ALLFAITH]

Is the tranny tunnel cut up so much b/c you went from auto to 5 speed ?

I plan to go 4 speed to 5 speed on a 69, but have heard there i only minimal cutting for a 4 to 5 speed conversion ? Anybody confirm this ?

Brad

[6t7gto]

check this out.
it really shows the crossmember refab.
http://forums.performanceyears.com/g...11&m=999100717
david

[GS470]

Guy/Ed - I'll give both of you a call w/in the next couple of days, probably in the evening.

Guy - I actually switched from 3.55 rear gears to 3.08s because of the tranny. Even the 3.08s give me about a 4.00 rear gear equivalent when in 1st gear, which is plenty steep for my 468 (I shift at about 5400/5500). This combo gives me a setup that works great for the driving I do. Sounds like you're anxious to give the guy on that 200mph bike a run for his money.

6t7gto - I installed the two rocker switches over 20 years ago, so I (obviously) don't remember what they are. One was for fog lights (it was the "in thing" way back then, and yes, they're still on the car ) and the other was for a rear defroster. The defroster is long gone, so I use that switch for my elect fuel pump now. Whose hydraulic clutch mechanism did you go with? What kind of price tag did it carry? That must be nice to have.

Regarding the tunnel, I don't know if tunnel size varies between AT and MT cars or not, but there was no way my TKO II was going to fit in mine w/o cutting the top off (or beating the hell out of it). If you're concerned about keeping your tunnel intact, it sounds like modifying the crossmember may be the way to go (I didn't alter my crossmember and I'm using a stock rubber tranny mount). My driveshaft angles were good on both ends, I have no drivetrain vibration and cutting the top off the tunnel didn't bother me, so this solution worked in my situation.

[Silver Judge]

The conversion to a Tremec is an awesome one.
I have a '70 GTO with a Muncie M22 but know a guy with the same basic horsepower, torque, and rear end gears in a '70 and he had no problem doing 155 mph

[6t7gto]

gs470,
my car had all this in it when i bought it two months ago.
i don't know the make of the hydraulic M/C.
i have had it out to rebush the clutch pedal but there is no mfg. name on it.
i do have the external slave cylinder on the clutch fork. it is a pull type throw out bearing on the pressure plate.
i have no problems with engagement or disengagment.
david

[6t7gto]

as far as me refabbing my crossmember, the previous owner had the trans crammed up tight against the floorboard.
i redid the crossmember after finding that other post i referred to.
now my car is vibration free.

david

[6t7gto]

my clutch M/C is similar to this...
http://www.stockcarproducts.com/clutch9.htm
david

[matrix]

I have been researching the hydraulic clutch setup a bit. Seems the throwout bearing style has a reputation for leaking but is the easiest and cleanest to install as opposed to the external slave cylinder style. The throwout bearings range from 150-350 dollars and the master cylinders 50-150 dollars. There are so many available that I managed to confuse myself slightly. Im concerned with getting the MC and Bearing matched properly with the correct pedal throw and bearing travel at the pressure plate.So for me the right choice will be the Keisler kit. They say it is a complete bolt on. The MC passes thru the firewall in the same hole the stock pushrod would and the throwout bearing is self adjusting. It was explained to me by one of their techs that the bearing is made by a european manufacturer and is OEM on Mercedes Trucks used in Europe. The bearing also rides on the pressure plate fingers constantly. Automatically retracts just enough like disc brakes do. And no the bearing wont wear out prematurely from constantly spinning. That is what it is supposed to do. Differnt style bearing than what most of us are used to. Supposed to be good for several million cycles. And I did notice tonight on "Rides" that the same bearing was being used on the Mega-dollar Mopar "Hammer". I will let you know how it goes in a couple weeks when i get around to it. Still working on the Vintage Air now.