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4+3 trans swaps

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Old 03-29-2007, 09:45 AM
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joseph farrell
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Default 4+3 trans swaps

i have an 86 4+3 car w/ missing trans, wich transmisions are swappable? i was thinking about a 5 speed from an 82-92 f body. if i remember correctly those cars use a simiular tourqe arm. anyone ever tried a regular rear trans crossmember?
Old 03-29-2007, 10:02 AM
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anesthes
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Originally Posted by joseph farrell
i have an 86 4+3 car w/ missing trans, wich transmisions are swappable? i was thinking about a 5 speed from an 82-92 f body. if i remember correctly those cars use a simiular tourqe arm. anyone ever tried a regular rear trans crossmember?
welllll..

I considered that, but bailed due to time.

The T5 out of an fbody uses the same clutch, same flywheel.

Question I couldn't get answered was bellhousing. If you mate a T5 to a Fbody bellhousing you get the same length as a 700R4, so you can use an auto/dana36 driveshaft + cbeam.. I don't know if the T5 will make to the 4+3 bellhousing. If you can solve the bell housing mystery, then on to the next step.

As far as the Cbeam / torque arm goes that should be VERY straight forward. Infact, the fbody tail shaft has bolt holes for a torque arm mount. You should be able to mill out of a block of aluminum a Cbeam mount that will bolt right to the tail shaft.

Now once you have the bolt pattern/bellhousing issue, and Cbeam issue resolved we are left with only 1 remaining problem. The T5 shifter is in the dead center of the tranny, and might not be where your 4+3 hole is. (could be too far forward or back, and most likely to the right). That you're gonna have to figure out on your own. Now you can probably cut the shifter in 1/2, and weld a offset plate to it to correct that issue.

If you want to measure your 4+3 bellhousing (if you have one) distance from block surface, and bolt pattern spacing, i'll get T5/fbody measurements and we can at least determine if the T5 will bolt up.

-- Joe
Old 03-29-2007, 10:15 AM
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88BlackZ-51
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Go with a ZF6, It will bolt up with minor adjustments.
Old 03-29-2007, 10:37 AM
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JLeatherman
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If you just wanna get the car on the road, there's a 4+3 for sale with everything attached to it still in the for sale section of this site for $800.

If you really wanna swap a trans in the question becomes how much money you got? I personally wouldn't go with the ZF swap. They're really expensive to rebuild and if you buy a rebuilt one by the time you're done getting the other parts for the swap you've spent as much as swapping in a Keisler. The Keisler trans is my favorite choice for going into the vette. Check out their website at www.keislerauto.com for details. It's pricey, but it is a direct bolt in and their trans's are always first-rate quality.

If you really want to have a go at some custom work (either you can't afford a Keisler or you have a lot of time on your hands) there is an adapter for sale at www.prostreetcustoms.net for bolting a C-beam to a T56. The T56 from an LT1 Camaro has the shifter the right distance from the bellhousing, but you need to make a custom coverplate because it sits to the right an inch or two.

For the T-5 and anesthes other questions, I'm pretty sure the T-5 will bolt up to a 4+3 bellhousing.

Here's a T-5 Bellhousing:
http://www.fbodymotorsports.com/inc/sdetail/8098

And here's a 4+3:
http://www.vetteweb.com/tech/vemp_05.../photo_11.html

Bolt pattern look the same, as were most GM transmissions for many years. The shifter should be in about the right place as far as distance from the bellhousing because you can swap an LT1 T56 into an f-body and the shifter is in the right place, and you can swap that same T56 into a C4 and the shifter is in the right place except side-to-side.

If you have some time on your hands and/or access to a cheap T-5 (there are lots of them) I'd say give it a shot. Know that you will definitely need a custom shifter cover cause the shifter will be half-way into the cupholder. I would likewise be interested if you go ahead with this.
Old 03-29-2007, 10:56 AM
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anesthes
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Originally Posted by 88BlackZ-51
Go with a ZF6, It will bolt up with minor adjustments.
Lots of money for a one off, not very good transmission. Big money flywheel and clutch. Big money tranny that was only used a few years.. I say T5, or T56 is the best route.

And before some expert chimes in with power handling figures, I've run faster times in a boosted bird than a majority of CF members with a T5 setup with no problems. T56 would be slick for the 6th gear though.

-- Joe
Old 03-29-2007, 11:40 AM
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CentralCoaster
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Originally Posted by anesthes
Lots of money for a one off, not very good transmission. Big money flywheel and clutch. Big money tranny that was only used a few years.. I say T5, or T56 is the best route.
Untrue. This swap will cost you about $2400 with a new tranny or $1500 with a used one, including the new clutch and bell and hydraulics.

There is very little clutch selection though and I don't like the clutch design. But compared to the other "bolt-on" options, Rich6 and TKO, you have to consider it for the price.

Whoever told you the trans is "not very good" is full of
Old 03-29-2007, 11:58 AM
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Thrak
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Originally Posted by anesthes
Lots of money for a one off, not very good transmission. Big money flywheel and clutch. Big money tranny that was only used a few years..
I didnt spend very much for my 4+3 to ZF swap... used the 85 flywheel, so it wasnt big money, and the clutch came with the trans...

So far, I love it... the gear clatter isnt that bad either.

Last edited by Thrak; 02-06-2008 at 08:11 PM.
Old 03-29-2007, 11:58 AM
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anesthes
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Originally Posted by CentralCoaster
Untrue. This swap will cost you about $2400 with a new tranny or $1500 with a used one, including the new clutch and bell and hydraulics.

There is very little clutch selection though and I don't like the clutch design. But compared to the other "bolt-on" options, Rich6 and TKO, you have to consider it for the price.

Whoever told you the trans is "not very good" is full of
I've driven them. They are not a good trans. Compared to a T5 or modern T56, they just drive silly. The shifter is weird, the whole thing just doesn't feel good. My opinion. Plus if you brake one, good luck getting it fixed cheap.

$1500 for a used manual transmission setup is insane. You can buy numerous 5spd's for that price. I really think corvette owners need to start thinking out of the box. I see a HUGE difference between thirdgen.org and this place.

Just my 2cents.


-- Joe
Old 03-29-2007, 01:17 PM
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CentralCoaster
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It "drives silly"? You sound like you're talking out of your ***.
Originally Posted by anesthes
$1500 for a used manual transmission setup is insane. You can buy numerous 5spd's for that price. I really think corvette owners need to start thinking out of the box. I see a HUGE difference between thirdgen.org and this place.


A used ZF goes for $750-$1000. Read carefully, the $1500 includes a NEW clutch set, NEW clutch master & slave, hose, used bell and driveshaft.

I don't appreciate your insults. I guess nobody is using the T56 because we're all ignorant.

Or maybe its because the T5/T56 won't work easily in the vette due to shifter location. So until you or someone makes it work with a new shifter or tailhousing, or a new console, you're pissing into the wind.
Old 03-29-2007, 01:32 PM
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anesthes
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Originally Posted by CentralCoaster
It "drives silly"? You sound like you're talking out of your ***.




A used ZF goes for $750-$1000. Read carefully, the $1500 includes a NEW clutch set, NEW clutch master & slave, hose, used bell and driveshaft.

I don't appreciate your insults. I guess nobody is using the T56 because we're all ignorant.

Or maybe its because the T5/T56 won't work easily in the vette due to shifter location. So until you or someone makes it work with a new shifter or tailhousing, or a new console, you're pissing into the wind.

First off, I've never insulted you. Infact, i've backed you up in another thread when someone else was stomping on you. I'm not sure how you could possibly take my post as an insult.

I don't like the way the ZF drives. I feel like your getting insulted because I don't like the thing. I think it feels goofy. I've built and driven a ton of non ZF cars. This is the first tranny I've hated.

Perhaps I'm 'pissing into the wind'. I didn't do the swap. But i've done numerous auto to stick swaps on other cars. If you want to check thirdgen.org, you'll find posts as far back as '99 of me doing stuff that others say couldn't be done. I just don't understand why nobody wants to try anything new around here. I stated how I think it could be done. I don't have the time to try it right now.

-- Joe
Old 03-29-2007, 02:03 PM
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Sorry, I don't own stock in ZF Industries or care what he decides to put in his car. I just don't like seeing people spread BS information. The ZF is a legitimate (and cheaper) choice and by saying otherwise you are limiting this guy's options.

Since you are apparently sold on the T56 and are so talented at doing these swaps, then why don't you do it? If it's so much better and cheaper, you won't have a problem selling custom parts for the conversion to make it worth your while. But you act as if you're the first guy to think of it.
Old 03-29-2007, 02:29 PM
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anesthes
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Originally Posted by CentralCoaster
Sorry, I don't own stock in ZF Industries or care what he decides to put in his car. I just don't like seeing people spread BS information. The ZF is a legitimate (and cheaper) choice and by saying otherwise you are limiting this guy's options.

Since you are apparently sold on the T56 and are so talented at doing these swaps, then why don't you do it? If it's so much better and cheaper, you won't have a problem selling custom parts for the conversion to make it worth your while. But you act as if you're the first guy to think of it.
Whatever. I'm trying to help. the guy asked about using a T5. I answered him. Seems like the only acceptable solutions around here are the easy ones. I dissagree with your point on cost, but you don't seem to welcome any other opinion. So I'm done with this thread. I hope the original poster got the answers he was looking for.

-- Joe
Old 03-29-2007, 02:36 PM
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You also have another option; you can replace the 4+3 with the Richmond 6 speed.

Here's the product description:
According to Corvette Fever Magazine, this transmission is the best replacement for the original equipment 4+3 transmission. Unlike the 4+3 which in practical use is a four speed with an overdrive, the Richmond gives you five gears plus an overdrive. Sold as a kit with everything needed to install, we have equipped this transmission with the ideal gear ratio set for the best possible street performance. Includes transmission with shifter.

Just an FYI, a lot of people say the gears are noisy with this tranny. I personally don't know because I'm still running with the 4+3. I only threw this tranny on here to give you one more option to look at.
Old 03-29-2007, 05:51 PM
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Joe,
We are not supposed to post ebay links here from what I understand but.....I have a complete and working Doug Nash 4+3 set up listed for $300 that ends in a couple days. Just thought I would throw that out for another option. I'm doing the ZF swap and I'm in for 3 grand w/ mostly new parts + used bellhousing / clutchfork / master...etc
Old 03-29-2007, 06:09 PM
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3K sounds a little steep. How much did you pay for the trans?



Joe, I also have a 4+3 for sale, it needs a new overdrive front seal though. I'll probably just put one in if nobody wants it as is.
Old 03-29-2007, 06:28 PM
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Hi Central,
1450 +150 s/h for the new tranny then add the Ram conversion (clutch/pp/al FW and hyd.throwout bearing)=1100, used bellhousing,master cyl,pinion yoke=330. Add a longacre ss line@ $30..........
Old 03-29-2007, 06:28 PM
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T5's are really weak- GM wouldnt even put them behind L98's in the camaro, so steer clear of that- any of the other trannys are good, though (no matter what some people are trying to tell you)

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Old 03-29-2007, 06:38 PM
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I have a paper weight on my desk that is an old T5 3rd gear. I had a mustang running in the 12's and blew 3 of them up. You can call Liberty gears and ask them. I was thinking of the ZF6 swap but they guy that we buy or trans stuff from just told us to rebuild the 4+3 as it would be as strong,lighter,and a whole lot less complicated. He's got 30 years experience so we a rebuilding the 4+3. Just my .02


AL
Old 03-29-2007, 07:00 PM
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CentralCoaster
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mrc, I missed the part about the RAM conversion clutch. With that setup, you've got the weakest link taken care of, IMO (and are still under the cost of a bolt-in TKO or Richmond kit.)

Originally Posted by AUTO_X_AL
I was thinking of the ZF6 swap but they guy that we buy or trans stuff from just told us to rebuild the 4+3 as it would be as strong,lighter,and a whole lot less complicated. He's got 30 years experience so we a rebuilding the 4+3. Just my .02
I'm guessing had you swapped to the ZF this guy wouldn't be making any money on the deal. The 4-speed is very stout though, I'm not sure why so many people knock it for power handling. Of course it won't hold up being abused in overdrive, but which trans does?
Old 03-29-2007, 10:06 PM
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Default trans

imho
normal driving, use the overdrive
non normal driving.........don't touch that button until it's almost wound out and the torque is almost gone


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