Muncie to T56 swap

[deckofficer]

Well, today the hydralic throw out bearing actuator puked and left me without being able to disengage the clutch. No problem as I can easily shift without using the clutch and if I get caught at a stop light, just slide to neutral, stop, turn off engine, put in 1st gear, and when the light turns green, hit the starter. But since the future upgrade to the T56 Magnum 6 speed would require a new hydralic clutch servo, the time has come NOW to swap the trans, so this failure won't cost me any additional bucks over the cost of the swap. First issue was measuring the driveshaft that will have to shortened to accomadate the longer T56. My yoke to driveshaft angles are already a little larger than preferred and shortening the driveshaft will increase those angles. I'm researching going to a CV joint to replace either or both of my u-joints. Does anyone have any thoughts on this?

Thanks,
Bob

 

[2old2fast]

D.O. ,obviously I can't tell what your driveshaft angles are now [fromthe picture] ,but you can operate succesfully w/ up to 3* w/ no problem. how much are you expecting to have w/ the new tranny setup?
dave

 

[Ted Brown]

Bob, Your drive shaft looks plenty long to me, mine is only 71/2" C to C of U joints and my rear end moves up and down a total of 4 inches... So I would think yours should be fine... as your rear end does not move up or down...

 

[deckofficer]

It's over 3 degrees now and will be greater with the need to shorten the drive shaft. I'm looking into what the 4X4 crowd is doing when they jack up their suspension as much as they do. I think a double cardine type CV joint should work on my Track T, but I am looking forward to input on this before I start spending money. Check this out and comment please.

Bob

http://www.4xshaft.com/index.html

 

[old round fart]

Bob, It looks to me if you contacted Tom and told him your concerns you would get better info than any of us could give you. You can't beat a man at his own game!

 

[deckofficer]

I'll be calling him tomorrow. Just wanted to know if anyone has needed to do this for the same reason.

Bob

 

[deckofficer]

I feel like I'm 20 again, trying to put a square peg into a round hole. The T56 is 4" longer and with my drive shaft to yoke angles already at the max of +3%, I thought maybe a CV joint would work. Problem is a CV should not be used on a splined yoke, so the experts tell me. Ironically, since there is no change in distance durng suspension travel with a Jag IRS, I don't even need it to be splined. A TKO 600 5 speed trans will bolt up to my bell housing (saving $500.00) and is only 1.5" longer. Also this trans costs $600.00 less than T56 for a total savings of $1100.00. Kind of a strong incentive to go with a 5 speed and give up on my dream of a 0.5 overdrive ratio. I can get a 0.64 overdrive in the 5 speed and because I don't need to center on the tranny output splines (remember, no travel) I might get away without having to shorten the driveshaft. If I have to shorten, might only need to trim about 0.75" which on a 18" drive shaft will not increase my angles much at all. Still looking for input from folks that have "been there, done that".

Thanks,
Bob

 

[2old2fast]

$1100, that's REAL incentive !!!!! more'n enough for me . dave

 

[Screaming Metal]

http://www.driveshaftsuperstore.com/transmission_and_transfer_case_slip_yokes.htm

Well, I've been sitting on the sidelines, playing paddle-ball and am wondering....What trans do YOU want to run? If your not going with the trans you want, just because you a few degrees out on your drive-shaft angle, drop the rear of your trans. You can tweak your crossmember either at your frame attachment points or your trans mount or both. You can do that just a touch and then raise your pinion, just a touch.
From what I've heard, you can shim things that much to get the right angle. Maybe I'm reading your problem wrong, but that 5 speed is what you want, correct? If the 5 speed will do it for you for alot less...go with it.
Remember, your pinion angle is there for when your suspension is under total load....your crankshaft, driveshaft and your pinionwill form a straight line. Theres nothing is the cosmos that says that the world and your bucket is gonna fly apart at the seams the first time on a bounce in your suspension that all the angles aren't perfect.
Look at the Monster trucks.... Theres one in particular that I'm very familiar with and they have mucho, mega over-angle on the front and rear pinions and with the driveshafts and CV type of joints they have....the driveshaft itself telescopes (internal and external spline type)....this fella is throwing a few thousand horses to the puppies and they don't pop them but on occassions when the bolts usually shear or something twist intwo.
Get it close....it doesn't have to go into orbit. You are allowed some tolerance!
You have at least 1/2 a degree of play in just your motormount/trans mount and the bushings on your leaf springs.
If your running a jag, you can heat your brackets and bend them to come within spec....
It ain't nothin a cuttin torch, a plybar and a welder won't cure!

 

[Screaming Metal]

Your rear doesn't move, ( I re-read the post) so, evidently your running a IRS. Ted Brown knows his cars and rods, if he says you'll be OK, you'll be OK. He's built more ground up cars than most folks have had prs. of socks....Not to mention the supercharged race cars he and a few others used to build....

 

[409T]

Still looking for input from folks that have "been there, done that".

Thanks,
Bob

I just measured the drive shaft on my 409 T, and it angles to the right 5.2 deg. and down 7.5 deg. when at rest. At least that is what I get with a tape measure and a little trig. Going over bumps who knows how much it deflects. Just looking at my 4 X pick-up I would guess that it's drive shaft angles down about 15 degrees (truck is heavily raised) and it has 89,000 miles on the u-joints, lots of that off road, with no problems. In Ted's example where he has a 7.5" drive shaft that goes up and down 2" for a total travel of 4", his angle at 2" up or down is 15.5 deg. if it starts at 0 when at rest. That is if my math doesn't fail me, your mileage may vary.

Jeff

 

[deckofficer]

RPM First Gear Second Gear Third Gear
75 2.0 3.1 3.9
150 3.9 6.1 7.8
225 5.9 9.2 11.7
300 7.8 12.2 15.6
375 9.8 15.3 19.5
450 11.7 18.3 23.4
525 13.7 21.4 27.4
600 15.6 24.4 31.3
675 17.6 27.5 35.2
750 19.5 30.5 39.1
825 21.5 33.6 43.0
900 23.4 36.6 46.9
975 25.4 39.7 50.8
1050 27.4 42.7 54.7
1125 29.3 45.8 58.6
1200 31.3 48.8 62.5
1275 33.2 51.9 66.4
1350 35.2 55.0 70.3
1425 37.1 58.0 74.2
1500 39.1 61.1 78.2
1575 41.0 64.1 82.1
1650 43.0 67.2 86.0
1725 44.9 70.2 89.9
1800 46.9 73.3 93.8
1875 48.8 76.3 97.7
1950 50.8 79.4 101.6
2025 52.8 82.4 105.5
2100 54.7 85.5 109.4
2175 56.7 88.5 113.3
2250 58.6 91.6 117.2
2325 60.6 94.6 121.1
2400 62.5 97.7 125.1
2475 64.5 100.7 129.0
2550 66.4 103.8 132.9
2625 68.4 106.9 136.8
2700 70.3 109.9 140.7
2775 72.3 113.0 144.6
2850 74.2 116.0 148.5
2925 76.2 119.1 152.4
3000 78.2 122.1 156.3

This is the main reason why I still want the 6 spped. The first speeds are with my current 1 to 1 Muncie. The second would be with the 0.64 overdrive of the TKO 600 5 speed, The last numbers (far right) are the T56 with the 0.50 overdrive. I really want to cruise at 60 mph at just 1250 rpms. The light and slow exhaust rumble would be just perfect. I have done the old "pros and cons" with each choice.

Pros of the TKO 600 5 speed
1.) $1100.00 cheaper
2.) No or little drive shaft/couplers issues
3.) Easier to feel, wider shift gates.

Pros of the T56 6 speed
1.) 0.50 overdrive. But this is where Screaming Metal has a point, I do want that tall of gear.

 

[deckofficer]

If I can find the 2.88 Jag rear gears, the 5 speed (middle colum) will give the cruising rpms I'm looking for.


1050 33.6 52.5 67.2
1125 36.0 56.3 72.1
1200 38.4 60.0 76.9
1275 40.8 63.8 81.7
1350 43.2 67.5 86.5
1425 45.6 71.3 91.3
1500 48.0 75.1 96.1
1575 50.4 78.8 100.9
1650 52.8 82.6 105.7
1725 55.2 86.3 110.5
1800 57.6 90.1 115.3
1875 60.0 93.8 120.1
1950 62.4 97.6 124.9
2025 64.8 101.3 129.7
2100 67.2 105.1 134.5
2175 69.6 108.8 139.3
2250 72.1 112.6 144.1
2325 74.5 116.3 148.9
2400 76.9 120.1 153.7
2475 79.3 123.8 158.5
2550 81.7 127.6 163.3
2625 84.1 131.3 168.1
2700 86.5 135.1 172.9
2775 88.9 138.8 177.7
2850 91.3 142.6 182.5
2925 93.7 146.4 187.3
3000 96.1 150.1 192.1

 

[Screaming Metal]

If I can find the 2.88 Jag rear gears, the 5 speed (middle colum) will give the cruising rpms I'm looking for.


1050 33.6 52.5 67.2
1125 36.0 56.3 72.1
1200 38.4 60.0 76.9
1275 40.8 63.8 81.7
1350 43.2 67.5 86.5
1425 45.6 71.3 91.3
1500 48.0 75.1 96.1
1575 50.4 78.8 100.9
1650 52.8 82.6 105.7
1725 55.2 86.3 110.5
1800 57.6 90.1 115.3
1875 60.0 93.8 120.1
1950 62.4 97.6 124.9
2025 64.8 101.3 129.7
2100 67.2 105.1 134.5
2175 69.6 108.8 139.3
2250 72.1 112.6 144.1
2325 74.5 116.3 148.9
2400 76.9 120.1 153.7
2475 79.3 123.8 158.5
2550 81.7 127.6 163.3
2625 84.1 131.3 168.1
2700 86.5 135.1 172.9
2775 88.9 138.8 177.7
2850 91.3 142.6 182.5
2925 93.7 146.4 187.3
3000 96.1 150.1 192.1

Looks to me you've got your answer. If you can't find those gears you want....the 6 speed is a good choice.

If you put a 5 speed in there, then gonna change your rear gears, too....just drop in the 6 speed and be done. Less work less mods....just my 2 pecos....

 

[Differen T]

The torque curve of your engine should determine the RPM's at cruising speed. Just as lower gears multiply torque, overdrives reduce torque. A .50 overdrive reduces torque by half and most engines don't make a huge amount of torque at 1250 RPM. This also rough on clutch disc hubs. An additional consideration is what happens in first gear with the six speed? If your Muncie is a close ration it has a 2.20 to 1 st gear and six speeds are generally closer to 3 to 1. Compare your current setup in every gear to the five and six speed. The five speed may turn out to be the more drivable solution. Without knowing the specifics I like the 5 spd, unless you have a radical beast you should begin to make good torque at about 1500 RPM's and 61 MPH and you won't have to down shift to get over bumps in the road.

Your posts show you like to drive your great looking T, Be careful not to create a vibration monster or one with useless gears because they are either too high or too low.

Al

RPM First Gear Second Gear Third Gear
75 2.0 3.1 3.9
150 3.9 6.1 7.8
225 5.9 9.2 11.7
300 7.8 12.2 15.6
375 9.8 15.3 19.5
450 11.7 18.3 23.4
525 13.7 21.4 27.4
600 15.6 24.4 31.3
675 17.6 27.5 35.2
750 19.5 30.5 39.1
825 21.5 33.6 43.0
900 23.4 36.6 46.9
975 25.4 39.7 50.8
1050 27.4 42.7 54.7
1125 29.3 45.8 58.6
1200 31.3 48.8 62.5
1275 33.2 51.9 66.4
1350 35.2 55.0 70.3
1425 37.1 58.0 74.2
1500 39.1 61.1 78.2
1575 41.0 64.1 82.1
1650 43.0 67.2 86.0
1725 44.9 70.2 89.9
1800 46.9 73.3 93.8
1875 48.8 76.3 97.7
1950 50.8 79.4 101.6
2025 52.8 82.4 105.5
2100 54.7 85.5 109.4
2175 56.7 88.5 113.3
2250 58.6 91.6 117.2
2325 60.6 94.6 121.1
2400 62.5 97.7 125.1
2475 64.5 100.7 129.0
2550 66.4 103.8 132.9
2625 68.4 106.9 136.8
2700 70.3 109.9 140.7
2775 72.3 113.0 144.6
2850 74.2 116.0 148.5
2925 76.2 119.1 152.4
3000 78.2 122.1 156.3

This is the main reason why I still want the 6 spped. The first speeds are with my current 1 to 1 Muncie. The second would be with the 0.64 overdrive of the TKO 600 5 speed, The last numbers (far right) are the T56 with the 0.50 overdrive. I really want to cruise at 60 mph at just 1250 rpms. The light and slow exhaust rumble would be just perfect. I have done the old "pros and cons" with each choice.

Pros of the TKO 600 5 speed
1.) $1100.00 cheaper
2.) No or little drive shaft/couplers issues
3.) Easier to feel, wider shift gates.

Pros of the T56 6 speed
1.) 0.50 overdrive. But this is where Screaming Metal has a point, I do want that tall of gear.

 

[deckofficer]

Differan T,

What you have said is very valid. The 383 stroker I just had built, I gave up a lot of horsepower at higher rpms so that it would be a torque monster at low rpms. Peak HP is a modest 320 at a low 4050 rpms. Torque is 516 lb/ft @ 2800 rpms. Car weighs 1790 lbs, so if I'm not totally nuts, a perfect canidate for gears that tall. As it stands now, I can climb out of steep mountain canyons with slow to 25 mph curves in top geat at 1000 rpms and pull decently and smoothly up the grades. I have checked the other gears of each transmission, 1st gear is still low enough, 62 mph @ 5500 rpms with 2.88 rear gears, 31" tires, and 0.64 OD.

Bob

 

[Screaming Metal]

I'm just thinking out loud here now....the diff. between the 6 speed and the 5 speed....$1100. Doing the 5-speed....mods to drive-shaft($80-150), mods to cross-member, possible shifter change(45-100), rear gears, gaskets, lube(200-350)....that 1100 is starting to drop rapidly, not to mention, all the extra time....

 

[Ted Brown]

Bob, Well my friend, like I told you when you were here in Bakersfield, if you like the low end grunt, you have got to choke that exhaust down... (that 2 1/2" pipe is for top RPM running) And if you want a taller gear, put taller tires on that critter, I run 33X12.50 BFGood... on mine, and it is plenty tall... final is 272 but driving at 60 MPH, I would never want to be at 1250 rpm, that would drive the bearings right out of my engine or the little man with the big hammer inside would do a lot of damage to my pistons I do believe, even if I am hard of hearing, I know it is still happening, that dreaded ping thing... Put a good vacuum gauge with at least 1/4" line to it, and that should tell you at what RPM to cruise... ya think?

 

[deckofficer]

Ted,

I have used tires in the past to attain a more favorable gear ratio for my needs. Back 20+ years I had an old tired Ford van that by DMV rules needed to be tagged commerical. I also have a CDL, and believe it or not was within the rules towing triples behind that van. An 18' flat bottom boat, a tent trailer, and then a little 10' shovel nose hydro boat. Just needed to be under 65' overall. The 351W in the van was a bit tired for pulling all of these over the summit to Tahoe and I needed new tires, so went to 50 series radials. Problem cured. If I go from 30" to 33" when I need rear tires, that will get me a little closer and will also give me a much needed 1 1/2" more clearance for my oil pan. I will probably go with the 5 speed and take things in steps. You and I have talked about restricting the exhaust, my question is with the way this engine was built, will it still increase my torque and/or lower the rpm the torque peaks at? Also, as you know, I'm not running any kind of tuned exhaust and wonder if an H pipe (cross over pipe) would be a good thing to add? The V10 Viper is geared the way I would like to gear, do you think at its weight it is a better canidate to cruise 65 mph @ 1250 rpms?

 

[Mike]

...and wonder if an H pipe (cross over pipe) would be a good thing to add?

Well, I'm not Ted (and Ted is doggone happy about that, too! :winkn, but the H-pipe would be a great thing to add. You will notice an improvement in the bottom end and it will also attenuate resonance. If you can squeeze it into your system, go for an X-pipe, instead.

People tend to think the exhaust is bolted onto an engine to get the smelly stuff dumped to the back of the vehicle. But anything you can do to help one exhaust pulse along the way, with the low pressure of the previous pulse, the better your cylinder fill will be. Remember, we are trying to use low pressure to signal that pressure-differential, air/fuel metering device atop the intake manifold. The formula to build race car headers is every bit as critical as the formula to build intake manifolds.