T5 or T56 swap?
 

With a 355, with around 340-375HP, that is not strip driven, only street(maybe 1-2 times a week, if that). Would I be able to use a T5? And would Hedman LTs fit without hitting anything? Or would and I have to use a T56? And would the LTs fit?

What about crossmembers? Are there any, fairly cheap, ones out there, that would be suited for dual exhaust? I know that Skulte Performance has one, but it costs as much as the T5 that I plan to purchase if I could get away with using one. :S

If you purchase a used T-5 try and get a later year, I believe 87 and up? Thats when they went to the World Class T-5's, much stronger than an early one. I had a World Class T-5 behind a fairly streetable 355 TPI motor. And it lasted about 6-8 months before I started hearing synchro problems. The T-56 is much stronger than a T-5 from a stock 3rd gen and can take a bunch more torque. I upgraded my motor to a 383 miniram motor and have a D&D Performance Viper/GM T56 retro fit tranny capable of handling approx 650ftlbs of torque. I scored the tranny for 2500bucks and its the same price as one from a 4th gen would be. I used a Skulte Performance crossmember and it cost 150bucks so it really didnt break the bank. You do know that a T-5 tranny bolts onto the automatic 700R4 crossmember right....some people say they dont but trust me they do. If you buy a T56 you'll need the crossmember not for the T5.

Check this link for more info:

https://www.thirdgen.org/forums/hist...ss-member.html

I run a T-5 in a 350/330 without issues (with Hooker 2055's), BUT I'm not a hotrodder. Safest bet in the longrun, perhaps, is the T56. By the way, IIRC, the so-called World Class T-5 arrived in 88. There are many members on this site who would scoff at the idea of this transmission's being called "World Class." If you decide to go the T-5 route, remember that two versions exist, one with a .63 fifth gear (low perf such as the LG4) and one with a .73 (high perf such as the L69).

JamesC

88 and up are the world class ones if you plan on using a t-5 which for you I don't think it would be a bad idea.

I was doing some research little while back about Hedman LT's and from what I gathered was they fit the t-56 but not the t-5 very good but I think I seen one pic of a guy that just dimpled the driver header some and it worked out for him but that is something you should look up yourself to make sure.

what if he just got the tko 500 from D&D. there a direct replacement for the t5. i dont know if it would clear the LTs thou.

Well I have sometime to find a tranny, if I find a fairly cheap T56, I'll most likely buy it, but I have time to think about it. How much do they usually run for used in junkyard?

$1500 is about the average going rate for a used T56 from the boneyards. If you look around a lot, you can usually find one closer to $1000-$1200.

Last one I saw at a swapmeet was $1200.

JamesC

How much of a direct replacement is it? New bellhousing? New Trans crossmember? It seems like verytime I see one of those for sale it is marketed to a ford product, will it bolt to the chevy stuff?

to be honest i dont know the answers to all of those questions. but D&D performace says that it is a direct replacement for the t5. thats what i will be going with when i switch to a 5 speed.

I tried the 3550 swap (a cheaper model of the tko 500) the kit contained a bellhousing adapter, (it wouldnt bolt to the stocker chevy bellhousing. it think it is a ford bolt pattern but dont quote me) brackets to relocate the stock bellhousing. You will need a new shifter because the trans it something like 17* clockwise, possibly a new yolk.. point is ask ALOT of ?'s before you buy one of these as it has the potential to turn into a pain in the ***

When you buy the Tremec trans they sell to replace the T5, they give you the adapter plate, which enables you to bolt it up to a stock T5 bellhousing. The 3550 model does have a Ford bolt pattern, but the newer TKO 500 and 600 have the GM pattern when you order them that way. The adapter plate rotates the trans to the proper offset angle for the thirdgens. They also include a 31 spline slip yoke when you purchase the trans. You have to get an adapter u-joint to mate it up to your factory driveshaft, unless they include that too. Your factory driveshaft is the correct length for the swap, just need the conversion u-joint. Spohn sells the correct conversion crossmember for the Tremec. You'll also need a speedo conversion part. Fortes parts connection sells the proper speedo adapter for either cable driven or electrical speedos. The only other issue is proper shifter location. All you have to do for this is make a plate out of flat steel with two sets of holes in it so you can move the shifter stick back about 2 inches, which will center it perfectly in the factory opening, or you can spend the extra for a custom fit shifter or stick. The GM spec TKO's also work with your original 26 spline, 10.5" T5 clutch assembly as well.

i just got done with the t56 swap and the headman longtubes with the ball type connection will not clear the slave i had to do major mods, but with some some basic fab skills its not to bad. i also ran dual 3" with dynomax bullets ill try to get some pics up.

in my opinion if you can find a good deal on a t56 there is no reason to buy a t5 the install is easy and basically bolt in. the only hard thing is the clutch master cylnder but you will have to do that anyway.

Yeah I would love to see some pic's, also what heads do you run?

How about the Hooker LTs? Do they hit on the T5s? I got a cheap t5, so thats what I'm using for now, until I can save some money to get a T56.

Since I don't have enough money to pay for a 9"/12 bolt rear right now, should I buy parts to build up the 10 bolt I have now? It'll be at least a year or two til I can gather the money to pay for another rear, and I cant seem to find a rear anywhere with decent gears, right now I have a one with 2.73 gears, and I could probably get a 3.23 or 3.43 non-posi for $100-200, but I'd rather spend my money toward the 12 bolt or at least spend that money for new gears to put in the 10 bolt I have now. I don't know what to do really, because I doubt the rear I have now will hold up against the motor til I get enough money to buy more parts.

The only way it would be cost effective to put new gears into your existing 10 bolt would be if you happen to have a buddy that'll set up the new gears for free, unless you know how to do it yourself. Otherwise you might as well snag a 3.42 or 3.23 non-posi rear from a 6 cylinder car, since those ratios are easy to find in the 6 cylinders. You'll hate running a manual trans with 2.73 gears. That's way too high for a standard trans. You'll end up smoking the clutch pretty easily. I wouldn't run anything less than 3.23's with a standard. The factory 10 bolt will actually hold up to quite a bit of abuse as long as you're not running slicks. Solid traction is what kills them, so as long as you spin the tires some, it'll live for quite a while usually. Just make sure to get the 9" or 12 bolt before seriously hooking up with slicks at the track!

Ok, that answer my question, thanks. Now I'm just wondering if the Hooker LTs hit anything on the T5, or if there is a way around putting a dent(how big exactly?) in the Hedman since they are quite a bit cheaper.