Cruising RPM and Manual Trans Options

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Map63Vette

Map63Vette

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So I've been debating seriously looking into a later model 5/6 speed trans swap in my 5.7, but I'm not sure what all to look for. My current setup (a stock 833) cruises around 3200 doing 70 on the highway. I looked into a Gear Vendors, but the .78 ratio only drops the rpm to 2500-2600 cruising which still seems a little high for my taste. I've mainly looked into a T56, but I'm not sure which ones to look for. I think a later model 6060 is out of the picture since I'd like to keep my mechanical speedo (have a stock gauge cluster and don't want to replace all of it or have another gauge mounted somewhere). The Viper ones have the super low .5 overdrive, which would drop the cruise to around 1600, but would this drag the 5.7 down too hard? The other common T56 overdrive I've found is .62, which puts the cruise around 2000. What are you guys cruising at with your Hemi swaps?

Are there any other good transmissions to consider? If I understand right the TKO is a purely aftermarket unit that's based on something else, so it's not something I'd necessarily come across in a junkyard or cheap on Ebay or something like that. From what I hear a T5 is mostly junk, just doesn't take much power stock and by the time I build it up I could just buy something else. Don't know of many others off the top of my head.

One other concern I have regarding the newer style transmissions is the shifting on them. The old 833 actually shifts pretty good, though it does miss occassionally (probably more my fault). My mom has a 94 Viper I've driven, and if you try to bang it real quick into third it likes to catch between the gates (it's like there's a notch between 1st and 3rd where if you are pushing forward it won't slide sideways over into 3rd or 1st). If you don't put a little extra sideways pressure on it coming out of second it will do it pretty often, but if you push too hard you get 5th. Unfortunately pretty much every other stick car I've driven is a cable setup, so the gates are really sloppy and I don't have any other comparisons. How do the new transmissions with internal shift linkage feel compared to an old Hust Comp Plus? Can you shift them as hard or do they feel flimsy?
 
From what I've found, there may not be any great factory options available. The TR6060 used in the new camaro's and Challenger's are told to be very clunky and noisy but if you take it to the dealer they will say it's normal. You obviously have experience with the T56 in your mom's viper. The only other thing I could think of is you might look for a world class T5 or something similar that someone has pulled out of their mustang. Should hold up to more power than the stock T5, but being used it should be cheaper. It's always a crap shoot though because you never know what you're buying. I'll be interested to see what you decide on. I'm trying to work on acquiring a 5.7 and would love to have a 6 speed behind it for my Dart. I'll probably be picking your brain for info if the deal goes through.
 
Lower RPM does not always equal better mileage (ask a Jeep 4.0 owner). Keep in mind that the RPM which your engine develops peak torque is also the RPM where peak volumetric efficiency is achieved. So you want the cruise pretty close to this.
 
True enough, though I'm not necessarily it in for the gas mileage entirely. According to the specs my engine should make peak torque at 4400, but that might be a little high for cruising, lol. Some of the driving force behind it is just not having the engine racing going down the highway. We have a 99 Vette that is practically idling going down the highway doing 1500-1600 rpm at 70 and gets 30+ mpg. The Viper is similar, you can barely even get the thing in 6th unless you're doing 70 (can get low 20's for mpg though). Even with the monster torque of the V10 the car is pretty much worthless in 6th, same with the Vette, but if you plan to drive for an hour on the highway it's nice to have it just chugging away instead of screaming. It is fun to be in the powerband while cruising though, whack the gas doing 70 and it's doing 80 before you look down at the speedo.

The other question is which would I rather have first, heads and a cam for 450+ horsepower or a 6 speed trans with overdrive.
 
I have a Hurst 03 Cobra billet shifter for my t56 and it is spring loaded to center. Haven't driven it yet but it sure seems like it compensates for the 2-3 hiccup. Your moms car might be equipped with the skip shift solenoid which can cause headaches as well. I wouldn't be afraid of any t56 being solid even if it needs freshening.
 
Yeah, the Viper does have the skip shift still enabled as far as I know. It's actually pretty funny, I just looked up the transmission for the Vette and it's a T56 as well, same ratios as the Viper too (though it's on a rear axle on the Vette). They both have a skip shift feature, though the one in the Vette is disabled at the moment. The difference is in the conditions that enable the solenoid. The Vette used to turn on the skip shift light all the time, but you have to try pretty dang hard to get the Viper to light it. You have to be below a certain speed and throttle percentage or something like that. I think the boys at Dodge set them stupid low or something in the Viper, I almost never see the light, even when just putting around town. The Vette lights it all the time if you're just cruising around in town in traffic.

I've been following your build recently Swinger, kind of one of the reasons I've been looking into even considering the swap. I don't really have the welding abilities or equipment to do the swap like some I've seen, but it looks like you're doing it almost entirely bolt in to the stock crossmember. I think I can borrow a CNC plasma table at work to make some of the brackets too, which would be nice. The Viper has a centering spring as far as I know, but maybe it just needs to be beefed up some. That or I just need to look at the shifter and see if there's something funny with it.

Trying to get a feel for pricing at the moment. The trans seems to run more than I would have expected, but I could probably make some of that back if I sold my 833. The bellhousing is the other moderately big ticket item. And I'd have to do something about the clutch setup (one of the other reasons I'm even considering the swap). I'm not sure there's a single A body part in my current linkage, though it's working well enough. Since a new trans would have the slave already figured out for me I'd just have to come up with a master setup.
 
I've got a spreadsheet I made on excel that has the 833, viper t56, tko600, tko500, and 727 side by side. You input tire height and rear gear, and it gives just about all the info you need, including first gear final drive ratio, mph at redline in each gear (at the redline you set), rpm when shifting from prior gear redline, and cruising rpm at a cruising speed of your choice. I'll email it to ya.

What I found is that the t56 and t6060 really have an "extra gear". What I mean is with the tko600, I can get a 10:1 first gear ratio with a 2100 cruising rpm at 75 mph. With a t56, a 10:1 puts the cruising rpm at ~1770. That is with different rear gears, FYI. Anyway, if anyone else wants the excel, let me know an ill email it or post it to my site for download.

As far as price goes- tko's and t56's can be had on Craigslist or other car forums for ~1500.

As far as strength goes- a camaro/firebird t56 is rated to 450 ft lb flywheel. A viper t56 is rated to 550 ft lb. A t-6060 is rated to 600 I believe. And a Tko500 is 500 ft lb, and a tko 600 is 600 ft lb. The fastest Tko600's with all the possible work done run 9.0's @155 mph 3200 lbs. There are faster t56's.

Shifting- some of the Tko guys complain about not being able to shift fast over 6000 rpm. There are guys you can send it to to polish and hangs a few things that should allow up to 800 rpm shifts with factory synchros. I don't believe that is a potential problem with the t56.
 
Cool, I was sort of playing with something like that yesterday, but not quite as detailed. I was just looking at the final gear ratio cruising rpm for a set rear end. The full spreadsheet would be handy to do a better comparison across all the gears and check gear spreads. Since I need new rear gears anyway I may opt for a different ratio than what I have currently to move rpms around and take better advantage of an overdrive.

I don't really intend to ever make the car super fast on the strip, mainly because I just don't have the means or money to make everything to spec for NHRA rules. Realistically I'll probably just run it at the track every once in a while for fun, so I'm pretty much limiting myself to 11.5, otherwise I have to start getting pretty crazy with all the safety stuff and I'd essentially have to gut the car and start all over cutting stuff up.

TKO's don't come out of anything from the factory correct? I've sort of started keeping an eye out for a T56 around the place, trying to determine how low the price has to be before I consider it to be too good to pass up. I need to add up all the other costs as well like a bellhousing, clutch pieces, and material for a rear crossmember. I'll have to keep an eye out for a TKO as well. On Tremec's site they say that the TR6060 can have a speedo output of some sort, is it just the ones from Challengers that don't have one? I'd also like to try to keep my front driveshaft yoke, so that may rule out the 6060 because it looks like it has a larger seal diameter.

I'll just have to convince my mom to let me take the Viper out for a spin so I can do some "research" on the shifting, lol.
 
I can make a call to Omaha if you would like to see what's available. I gotta real good Viper trans hookup there.
 
I have a small amount to input but nothing concrete yet.

I am putting a NV3500 truck tranny behind my 5.7 into a 67 coronet. I am not sure how long it will hold up to the torque but one will only see with time.

I am using a dodge dakota master and slave cylinder out of a 01 and the clutch out of an 03 ram 2500 with the ram flywheel. I don't have all the parts assembled in the car yet but in theory it should all bolt together with nothing not currently in a parts store. with my 2.94 rear end it should run around 1800 on the highway which is about the same as my 6000lb Ram.
 
Yeah, a truck trans crossed my mind the other day. I know I've seen them behind plain small blocks, so there's no reason it wouldn't fit behind a 3G Hemi to my knowledge. Haven't looked into the truck options much though. Frankly my knowledge of late model manual transmissions is pretty limited, you don't really hear names anymore. In the day you'd hear M-22 rock crusher, 833, and the other fun famous models, but any more nowadays you just hear 5/6 speed manual. I had a hard time even finding what some of the newers ones are. I didn't even know the C5 Vette had a T56. Went to look up what was in one since I've driven one for some comparison and finally found it after looking around for a bit. A ZF is about the only other one I've seen, though they're generally not talked about much and sort of a weird mix of parts.
 
Map63Vette said:
Yeah, a truck trans crossed my mind the other day. I know I've seen them behind plain small blocks, so there's no reason it wouldn't fit behind a 3G Hemi to my knowledge. Haven't looked into the truck options much though. Frankly my knowledge of late model manual transmissions is pretty limited, you don't really hear names anymore. In the day you'd hear M-22 rock crusher, 833, and the other fun famous models, but any more nowadays you just hear 5/6 speed manual. I had a hard time even finding what some of the newers ones are. I didn't even know the C5 Vette had a T56. Went to look up what was in one since I've driven one for some comparison and finally found it after looking around for a bit. A ZF is about the only other one I've seen, though they're generally not talked about much and sort of a weird mix of parts.
Click to expand...

I agonized over this for quite some time before I broke down and bought some parts so I have some research here. Here is what I learned (condensed):

Late model 5 speed truck trannies:

AX-15 (~87-95 V6 and V8 Dakota) - ~300 lb-ft of torque, good trans but not super strong for this application, need the small block bell housing

NV-3500 - (96-04 dakota, light duty ram v8/v6) ~300 lb ft rating (slightly conservative) and a decent trans. Some hold up well to modded 360's some don't depending on how much you beat on them. Built-in bell housing and relatively inexpensive (I paid $440 for mine complete)

NV-4500 - Full size hd truck trans, HEAVY, cast iron case, HUGE..never work here and way too tall of 1st gear. Also expensive, around a grand.


Car Trannies -

T-56/TR-6060 - (Ram SRT-10, Challenger, Camaro, Corvette, Some Mustangs) - Excellent trannies, both models are very similar. Must use the late model LS chevy trans if swapping as the LT-1 trans uses a diff input shaft which offsets the difference in cost. Very good torque ratings but also a minimum of $1200-1500 for just the trans plus $500 for a bell housing not counting clutch linkages etc.

T-5...too weak

and not much else out there that works easily here. For me on my budget the best option was the NV-3500 but as I stated before the torque rating is suspect and its a crap shoot. But I am not running track duty nor a heavily modified hemi. I plan to nurse this along until I can afford a T-56.

For any heavy track duty, launching, or general stupidity I recommend a TR-6060 or T-56.
 
Yeah, I plan to see the track a few times and in general the car is just too fun to not romp on some. I don't plan to do 5 grand clutch dumps around town, but I don't want to have to worry about blowing a trans out if my foot is a little heavy one day. I think at this point I'll probably just be happy with my 833 and if a crazy good deal comes up on a T56 I may bite. I'm hesitant enough to cut a sizable hole in my floor, plus I really don't want the car on jackstands in the driveway for another few weeks like when I converted over to fuel injection. The closer I can get to bolt in the better, lol.
 
So I was just looking through Keisler's site and noticed something. They have the RS 5 speed plastered on their main page, but I can't find any info for it on their site. I suppose that could be a possible option since I may not have to cut up my crossmember or tunnel quite as bad. I wouldn't necessarily buy their whole kit either (not that they have one), maybe just a bare transmission and any other essentials and make my own lower crossmember and clutch setup to save some money, but I can't even find a price for it anywhere. Does anyone have any knowledge of the RS trans? I saw them put one in a B body on TV a while back, so I was pretty sure there was a Mopar application for it that might be able to use a stock bellhousing which would save a decent chunk of money. If the trans is similarly priced to a T56 it might be a reasonable option.

Edit: Nevermind, I think I found some pricing info. Looks like $1500 for a bare trans (think that may come with a shifter at least). Doesn't sound like too bad of an option, though I don't know that I'm a real big fan of the gear ratios. Sounds like it will bolt to a stock bellhousing though.
 
Why not hold out for the Passon 5-spd? It seems it's almost here, and will be a drop-in replacement for your 833.

Grant
 
That's crossed my mind too, but I think I can get a 6 speed done for half the price if I play my cards right. I don't necessarily mind modifying my car that much because it's not really worth anything anyway (/6 auto from the factory and about half the sheet metal has been replaced already). The big one for me is cutting up the torsion bar crossmember. I don't have subframe connectors (yet at least), so I can't tie into them for a new rear crossmember like a lot of the builds I've seen so far.
 
you would have to cut the floor pan first and then add some tube/boxing and then clearance before cutting to retain the shape. It can be done without subframe connectors. I intend to make a set for my car as well.

In my case as far as waiting its just not in the cards as it will be a few years before I get to a point where I can afford something like that. I've been putting this thing together on a shoe string budget so far and have been successful. So far I have ~3k invested and that paid for the car, parts car, torsion bar x member, floor pan, 03 5.7, nv3500 5 speed and some other random stuff.
 
I finally found the thread I was looking for. I was thinking 72BBSwinger's build had the bolt in crossmember, but that's not quite the case. He made it bolt in to his subframe connectors, but there was a guy here with a Barracuda that did a bolt in crossmember that used the stock piece for a T56 Magnum swap. I think he drilled an extra hole in the stock crossmember because you have to cut the inside holes out to fit the trans, but that would be doable for me. It looks like he was even planning to make the top piece of the setup bolt in. Something like that would be nice for me because I think I can get the pieces cut on a CNC plasma table at work, tack them up myself at home, then have a guy in the shop at work weld them solid for a 6 pack of beer. I don't trust my welds or welder enough for something structural like that.
 
I will more then likely have to do quite a bit of cutting but I am going to use box tube to make a new lower bolt in mount and I have poly suspension bushings I am using for motor mounts and a trans mount. So I have some fab work to do there. I did buy a good welder this year so I can truly burn these things in right.
 
Yeah, I the other thread I was talking about is http://www.forabodiesonly.com/mopar/showthread.php?t=183871. Tjfly4Pay was doing a T56 Magnum (TR-6060) and making a bolt in setup using the stock crossmember. I think I could tackle something like that. I just have a little cheapo flux wire welder, so I don't trust it or me to do anything structural, but I think I can tack together an upper and lower bolt in crossmember and have someone else burn them in the rest of the way. My welder would be fine for putting the sheet metal back in I think, really more what it's meant for since it's pretty low power and it doesn't matter as much if I screw them up. I'll just cover them in seam sealer, lol. I need to pick up some sheet metal and start practicing so I'll be ready when the time comes.
 
If I were going to have to cut the car, I'd use a T-56 /6060. The 6060 is being put in cars with 600 HP TODAY, with a warranty which means they have to hold up. Though the factory does a number of things that cushions the transmission from the motor. For example, when you let the clutch out, the factory hydraulic slave cylinder is valved in such a way that you can't slam the trans with the full torque instantly. Further, EVERY new cars can overload the tires so the tires break loose so you won't be putting the full torque of the motor through the trans instantly. Personally, I've seen VW transmission live behind Chevrolet V8s the key is to not shock the transmission. Overall, I'd love to have a 6060 in my car, though I might be a little concerned if I wanted to drag race with slicks, and had over 500 HP.

I have not read that many positive reviews of the TKO. I personally think their 600 FT/LB rating is extremely optimistic. I've yet to see anyone drag race one of those transmissions and not break it, even behind a 500 FT/LB small block. Remember the TKO is simply a beefed up T-5

As for the T-5, it's not a bad transmission and I think if you were going to run a small rear tire, like a 225, not power shift, and not drop the clutch, it would probably survive. A fresh rebuild with a few upgrades and it would probably hold up to a stock 5.7. The nice thing about the T-5 is that they are small and light. Personally, I'd probably spend the money on a used T-5 and upgrades over the TKO. Especially since you can find used T-5 for under 200 dollars.

I've always like the idea of a Jerico 5 speed either a drag or road race transmission, but with prices STARTING at 5K (OUCH), it is a fantasy at this point. But hey, since I'm spending your money I think you ought to do it and let us know how it turns out! ;)

The Passon is a 4200 dollar transmission which many think this puts it out of the question right off the bat. But if you've already got the rest of the 4-speed stuff that is all you need to spend. As far as strength, he claims it will hold up to 650 FT/LBS of torque. Since he bent the frame of a car in testing, I think he's being honest in his 650 rating. Further, the gears are about 20% thicker than 833 gears and are made from better steel, so IF YOU PLAN TO DRAG RACE and do clutch drops with sticky tires this might be well worth the wait.

A833 PLUS Gear Vendors. Not cheap, even if you have the 833, the overdrive unit is $2700.00. The good news is Gear Vendors claims that their overdrive unit will hold up to 1200 HP! Plus you can split gears, this might make finding just the right cruising RPM easier.

PS, does anyone have any info or update on the Passon. Heard he had some porosity issues with the castings, not a strength issue, simply caused some leaks, but creating some consternation on his part.

Regards,

Joe Dokes
 
As as I can I will let you guys know how a 12 flat BB abuses a T56. If things go south I know a guy.....
 
i sure hope that passon 5 speed unit comes out soon. i really want it. sure hope he can fix the porosity issue...
 
Yeah, the Passon is a pretty interesting idea. If you look at it one way, most full swap kits will run you about the same amount as the Passon trans, so in the long run you spend around the same amount for roughly the same final goal. The difference being that with the Passon you only get one part for all that money as opposed to a crate of parts, lol. In the long run I'm really hoping to keep this swap under $2500, hopefully even closer to $2000 if I can.

The reality is that there really isn't anything wrong with the 4 speed I have in the car now. I've recently rebuilt it and bought all new linkage and everything. It drives fine and really has pretty nice gear ratios when compared against all the other options. I don't really drive the car on long trips ever, but I don't know if part of the reason is because of the trans. If I want to drive an hour to a car show doing 70 with the engine screaming at 3300 rpm the whole way it might get a little old.

The gas mileage argument is also sort of silly. I laugh at people that buy new cars for gas mileage sometimes because they don't realize they'll never make up the money they spend on a new car in gas unless gas prices get ludicrously high. If I get a 5 mpg increase with an overdrive and drive it every single day to work and back it would take me over 2 years to offset the cost of the swap in gas if prices stay somewhat consistent (and I really only drive it maybe once a week to work, so who knows how long it would take). If I get an increase of 8-10 that would be frickin awesome, but it will still take a while to see the savings. Now go out and trade in your old car and pay $20k on top of that for a new one. Even if you double your gas mileage you may not even own the car long enough to see that money come back to you, though it does depend on how much you drive. In my case, if I cut my gas bill in half every month it would take 20 years to save $20k on gas.
 
IMOP, You're on the right track with the reasoning to have an OD transmission. I have a 71 Challenger with a mild 360, and it has a 727 that I installed a Gear Vendor OD on. It has 3.55 gears, and when I'm running down the interstate at 70 mph, the rpm's are 2200-2300. The car does get 20 mpg, but that doesn't matter so much to me as it not twisting it's guts out to run with traffic. I'm putting the 545rfe in the 5.7 Hemi Duster for the same reason. Good luck with your 6 speed swap, and I hope it turns out like you want. :thumblef:
 
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