Okay, so I went drag racing on Saturday. I made one pass, first thing in the morning. A crappy one, too -- 13.99 @ 104. Considering that it was only 40 degrees out, that's especially crappy.

Anyway, I only made one run because at the end of that run, my shifter wouldn't come out of 4th gear. The clutch still worked fine, so I was able to get back to the pits. Lucky for me, launching in 4th isn't too hard, and the car can handle 3200rpm (75mph in 4th) without breaking a sweat, so I was even able to drive it the 70 miles home.

People who claim that they know what they're talking about have told me that I bent a shift fork. Others making the same claim have told me that I broke a shift pin. Either way, I figure the T56 needs to come out and get taken apart so we can figure out what's broken.

Since it's almost time to put the car away for the winter and since it's on my long to-do list to upgrade the trans anyway, this seems to me to be the ideal time to throw in some better parts.

So, I know that steel shift forks and Viper output shafts are popular upgrades. What else can be upgraded? Can I tweak gear ratios? If so, what are my options? What kind of parts costs am I looking at?

A friend of mine has access to cryo-treatment equipment and says he can get pretty much anything that's not too big cryo-treated on the cheap. What should I cryo-treat? Everything? Is there anything that specifically shouldn't be treated?

One more question -- about removal. Is it practical to remove the trans only, or is it easier to remove the engine and trans together? If the engine has to come out, that seems like an ideal time to do a set of headers, change the spark plugs, and maybe even throw a cam in there.

The car is pretty much stock now (mods in sig). Eventually, I hope to install a supercharger and run in the 450-500 rwhp range. I drag race occasionally and autocross once or twice a year, but the car is primarily a daily driver.

Go ahead, throw as much information at me as you can. Try to overwhelm me. I can take it!

 

Bump.

 

You probably are having issues with the 3/4 shift fork and even broke or bent the factory syncro keys located under the slider in the 3/4 hub . Its very common and now would be a good time to upgrade .

 

As far as removal the trans can come out easily with the engine in the car. Disconnect it from the bellhousing then pull the bellhousing from the engine. I've got pulling the trans down to about a 2 hour job.

 

Yup, tranny comes away from the engine easily. You don't even have to pull the bell-housing if you don't want, although this "may" be the time you want to upgrade your clutch? (if you haven't already).

Re-building the tranny "can" be a do-it-yourself job, with a couple of the right tools (gear pullers, namely) and a couple other odds & sods. Or, send it to one of the reputable builders, ie: T56rebuilds, or D&D performance (and I'm sure there are others).

I had mine apart last winter because of a really bad 2nd gear issue (the gear itself was screwed, where the synchro hub engages onto the gear) ... so I replaced that, along with all of the synchro rings. Tried to do it on a "budget", although it still got expensive, and the tranny still doesn't shift "perfect" in/between some gears . (however, I think I have unresolved clutch issues that are a factor ).

As far as changing individual ratios, 1st - 4th use a solid countershaft, so if you want to change one of them, you get them all (ie: C5 Z06 / Z51 gear ratios). 5th/6th are shared, and also have lower available ratios than stock. 4th gear will always be 1:1 though.

Based on my experience, I would have to say don't cheap out on parts. I don't think you have to get "Viper" internals, but get the best stock replacement components you can (ie: billet steel shift fork, carbon-fibre synchro rings, etc).

Hope that helps?

 

I'd like to do the clutch, but I'm not sure I can swing the extra cash. My stock clutch is still holding just fine, so I guess we'll see. I suppose that if I wait until January to start putting stuff back together (and I'm not going to have the car fixed before it gets stored for the winter anyway, so it's not like that makes a difference), I could put my annual bonus towards a clutch....

I'm definitely not the kind of guy to cheap out on parts. However, I'm also not the kind of guy that has lots of extra money I can spend upgrading the trans. The steel fork and the CF synchros I think are for sure. Viper output shaft -- maybe. What's the difference between the Viper shaft and the one I have?

I'd be interested in lower ratios for 1st-3rd. You're sure I can't change 4th too? Seems like I'd be setting myself up for a big ratio jump between 3rd and 4th. I really like the idea of improving low-gear acceleration without affecting 6th gear cruising RPM. That way I could stick with 3.42 rear gears.

 

if it only runs 104 in the 1/4 I would not dump big bucks in the trans.......

Find out whats wrong when it gets torn down and fix it......I would not upgrade a whole lot b/c its a waste of money at your power level(no offence) but money can be spent better else where

 

i would leave the clutch for now, after doing it once it really should not take you more than an hour in the future when you get money for a clutch

and if you plan to rebuild it yourself go to borge warner or tremecs site and email them and ask for the manual, it is very detailed and has pictures for just about every step and i have gotten them a few times

as far as tools you can get by with not very much, a shop press is prolly a must though

 

My best MPH, as you can see, is 108.9.

If you read the whole post, you'll note that I have plans to upgrade to a bit more power. Do you disagree that it's best to just do it while I have it apart?

 

Maybe other transmissions are different, but in the T56, 4th "gear" actually occurs by sliding a synchro hub over a "gear" (the gear that simply spins the counter-shaft) which makes a direct connection from the input shaft to the output shaft ..... basically, they "become one". So now it's a direct drive, 1:1 (whatever the motor is spinning, that's what's coming out the back of the tranny too). 1st-3rd can be changed, 5/6th can be changed, and heck, I think REVERSE could be changed, but I don't see any means of changing 4th to anything other than 1:1 .

I never even bothered pricing it out ... I'm sure it would be at least ~a few hundred bucks ... but I think the Z06/Z51 gearing (gives you lower 1st-3rd) would be a worth-while upgrade . That way you preserve your 3.42 ratio (as the 'Vettes do) which ultimately gives you good all-around "economy" and performance, yet you increase the acceleration potential of your car off the line. Best of both worlds, really .

 

I didn't know that! That's pretty cool.

That's exactly what I was thinking!

Plus, that couple hundred is money I wouldn't have to spend on a set of 3.73s.

 

Bump for some more questions!

I get an annual profit sharing bonus from work at the beginning of the year. I'm not sure how much it's going to be, but I'm expecting around $1500.

I'm trying to educate myself on how my money would best be spent. I have the means and time to do the rebuild myself (in a friend's garage; he has an input shaft hole in his workbench for this very purpose), and I have access to a T56 service manual.

SixSpeedsInc (formerly T56Rebuilds) has a bunch of rebuild kits available online. I emailed them a while ago, and Amber recommended their 2A kit. That kit costs $695 and contains the following:

1-2 Slider Assembly
3-4 Slider Assembly
5-6 Slider Assembly
Carbon Blocker Rings
Steel 3-4 Fork
Billet 3-4 Slider Keys
Bronze 1-4 Fork Pads

Interestingly, if I order the same parts a-la-carte, it comes to $670.

Other rebuild kits also include the following:
Reverse Slider Assembly
Front Input Shaft Seal
Tailshaft Housing Seal
New Bearings
New Snap Rings
New Shifter Cup
New gears and input shaft

Having not yet opened up the trans, I have no idea if I need new seals, bearings, or snap rings. I've determined that I can't afford to change the gear ratios. I have no idea what benefit there is in replacing slider assemblies, and I'm not even sure what a shifter cup is. Is it the little box on the end that the shifter mounts to? Or is it the little socket (as in ball-in-socket) that the shifter ball goes in?

Is a blocker ring the same as a synchro? Part of the synchro assembly?

Finally, there are several upgrade items that are only available a-la-carte. Among those, here are some I'm curious about:

Faceplated 1-2 or 3-4 Sliders (an extra $85 each)
Triple-coned synchros for 1st-3rd (but not 4th-6th?) (an extra $95)

What is faceplating? What's the benefit?

Here's something that is throwing me off: All of the kits are rated for 700hp/700lb-ft. Given that, what benefit is there in going with the more expensive kits?

Finally, should I be considering any shifter other than the Pro 5.0?

 

The reverse slider assembly only contacts one gear (the rest engage 2) and therefore can be flipped around, so you don't need to replace it until the next rebuild.

If you have a relatively low mileage tranny (under 100k) you probably don't need new bearings, snap rings, or a shifter cup. Seals may be a good investment though. The shifter cup is the rubber piece that the ball end of the shifter sits in.

The slider assemblies are the main thing you are replacing, they are the major part of the "synchro assembly." You'll understand better when you pull the tranny apart but basically there are teeth on the "face" of the gear called dog teeth. There is a matching set on the slider. The gear spins freely on the mainshaft while the slider is attached to the mainshaft via splines. When you shift you push the slider into contact with the gear, the blocker ring sits inbetween and serves to speed the gear up (or slow it down) to the same speed as the slider before they engage.

Faceplating changes all of the synchro stuff I just told you about. Instead of a couple dozen dog teeth they are replaced with half a dozen big teeth. Drag racers use them because they are strong and you can basically "shift without lift," or keep your foot in the gas while shifting (you still need a little clutch action). It's not the most streetable thing in the world though. And that extra $85 each is just the sliders, the gears need to be faceplated as well. Go ahead and put away $1500 if you want to do that to your tranny.

The triple cone sliders are for the Z06 vettes. If you did want to swap gears you would need those, along with the $500 blocker ring set. I'm still not entirely sure that it's possible. The easiest way to get better low gear ratios is to use the '93 gearset, but I don't know if there are any differences between the main and counter shafts. The 1-4 countershaft drives the 5-6 mainshaft, and vice versa. So if there is a difference in either you won't be able to keep your 5-6 ratios. Not to mention gears are expensive!

Most of the more expensive kits are just replacing more things in the tranny, not necessarily upgrading.

Hope that helps.

Jeremy

 

what are your future plans as far as power? exact plans

need to know where and how it makes the power.......

 

My intent is to build an all-around, reliable performer. Handling, acceleration, braking, etc. I'd like it to run high 11's in the quarter at full weight on drag radials. Tires will be the only drag-specific item on the car. I intend to beef up the whole driveline. I didn't think I'd do the trans first, but hey -- as long as it's apart, right?

I suspect that the best/easiest way to reach those goals is with a Procharger. Target is in the 450-500rwhp range. However, having recently discovered that $10,000 will get me a Katech LS2-based 427 long block with fully forged internals and L92 heads (550+ at the flywheel, depending on the cam), I'm starting to wonder if something like that wouldn't make me happier. When all is said and done, that's not much more expensive than it would be to build up my engine to be relatively reliable on boost.

Reliability and streetability are key. I want to be able to hand the keys to my wife and send her off with the car on a reasonably long trip and not worry about her getting stranded or it being too much car for the street. Peak power is not particularly important to me -- I want a nice fat torque curve. I've seen a dyno graph for that Katech engine -- it made 450 lb-ft at 2500 rpm (this was a version with ported heads and a hotter-than-normal cam).