Convert 4+3 to a ZF6?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
well... judging from your comment, you really have no clue what this is about!
I don't mean that in a bad way, just observationally speaking.
The ZF6 is a much more modern gearbox than the 4+3. Where the 4+3 has an external gear change and linkage, the ZF has an internal shifter.
The ZF and 4+3 are the same length, but none of the existing components, save the c-beam, will transfer.
As I understand it, you will need the ZF bell housing, hydraulics and clutch assembly.
I will warn you, the ZF is NOT a quiet gearbox. you will get idle rattles... but you might also get droning from the gearbox... it's a pain, really.
The person to talk to regarding this conversion is CentralCoaster. Infact, if you do a search on him here in C4 Tech, you will find his threads regarding this conversion.
Something to consider, Kiesler Engineering has the TKO 5spd available... the 5th gear OD is about the same ratio as 4th gear with OD engaged on the 4+3. The cost is about $3k, complete.
TKO is a part of Tremec.
I don't mean that in a bad way, just observationally speaking.
The ZF6 is a much more modern gearbox than the 4+3. Where the 4+3 has an external gear change and linkage, the ZF has an internal shifter.
The ZF and 4+3 are the same length, but none of the existing components, save the c-beam, will transfer.
As I understand it, you will need the ZF bell housing, hydraulics and clutch assembly.
I will warn you, the ZF is NOT a quiet gearbox. you will get idle rattles... but you might also get droning from the gearbox... it's a pain, really.
The person to talk to regarding this conversion is CentralCoaster. Infact, if you do a search on him here in C4 Tech, you will find his threads regarding this conversion.
Something to consider, Kiesler Engineering has the TKO 5spd available... the 5th gear OD is about the same ratio as 4th gear with OD engaged on the 4+3. The cost is about $3k, complete.
TKO is a part of Tremec.
Race Director
Joined: May 2003
Posts: 10,749
Likes: 41
I drove a ZF6 the other day. Yes the tranny is smoother, but its not that much smoother for me to spend $3000-$4000. There is something about the 4+3, It keeps it original, and there arent many out there. I can shift just as fast as a ZF6 with my 4+3. I installed the short throw linkage, I think it helped.
Last edited by 88BlackZ-51; Apr 16, 2006 at 08:21 AM.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by Siveck
What is involved with converting a 4+3 to a ZF6? Anything more than the actual tranny and shifter?
I put a zf in my 85, also have the 4+3 here sitting on the floor that I'm gonna rebuild in the next few weeks.
Le Mans Master
Joined: Sep 2000
Posts: 6,303
Likes: 714
From: Bartlett IL
Originally Posted by 88BlackZ-51
I drove a ZF6 the other day. Yes the tranny is smoother, but its not that much smoother for me to spend $3000-$4000. There is something about the 4+3, It keeps it original, and there arent many out there. I can shift just as fast as a ZF6 with my 4+3. I installed the short throw linkage, I think it helped.
Sorry. After having lived with a 4+3 for 20years, there's no comparison.
And the short throw linkage is a POS IMHO.
Thread Starter
Drifting
Joined: Aug 2002
Posts: 1,775
Likes: 125
From: Birmingham AL
Thanks everyone for the input. I'm just posing the question for a hypothetical situation. I looked at an '87 vert with the 4+3 last night. I was just wondering how difficult it would be to change to a ZF at some point if I bought a 4+3 car. It seems like it would be much easier to convert a 4+3 to a ZF than to convert an auto to a ZF. You would already have the pedals, console trim, hole in the floor, D44 and so on. I'm probably going to hold out for an '89 vert with a ZF. However, this could be useful information for anyone wanting to do the swap.
Team Owner
Joined: Jun 2001
Posts: 26,196
Likes: 0
From: Orlando FL
St. Jude Donor '08-'09
Originally Posted by bogus
I will warn you, the ZF is NOT a quiet gearbox. you will get idle rattles... but you might also get droning from the gearbox... it's a pain, really.
I had a dual mass for many miles and 2 clutches. I converted to a single mass (and clutch 4 now) and it chatters like crazy in neutral... I was told that even before I had it installed... it doesn't bother the car, but it's a bit embarrasing sometimes when the chatter is noisier than the nice cam lope sound ...and you have to explain to people "umm theres nothing wrong with it, its just the ZF6 and a single mass flywheel"
i love mine though, but NOBODY wants to work on them, much less has anyone know what they are...they have like 3x the parts as any of the other trannies from what I understand.
They are rock solid though.
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Dude, keep it a 4+3. I've gone from one to a Richmond 6spd and the gear noise made my vette sound like a diesel truck. This is something everyone failed to mention to me before the conversion. The richmond is more than rock solid but my car is a vette...not a racing car. I went back to the 4+3 (not an easy counter-conversion). Had the 4+3 rebuilt. Had the OD rebuilt. Now I enjoy the quiet of a sports car transmission. If and when I break it....I will have it rebuilt. Nothing lasts forever, and as most people willl bash this tranny, I PRAISE IT. Properly rebuilt, properly maintained, and most of all the linkage propertly lubed and ADJUSTED it will be a joy to drive. The 4 speed is basically the same as any other GM 4 speed out there. The OD should be disengaged when dueling.
Anybody want a a richmond 6spd with less than 150 miles on it? For sale. Whole kit.
Anybody want a a richmond 6spd with less than 150 miles on it? For sale. Whole kit.
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Safety Car
Joined: Oct 2002
Posts: 3,991
Likes: 0
From: Phoenix AZ
This is not a ZF but the before mentioned TKO swap KIT, check it out.
http://www.keislerauto.com/gm/transm...ette_84-88.asp
And if you really want a 6 speed I would recommend Richmonds T56 swap kit here.
http://store.summitracing.com/partde...5&autoview=sku
some more random info here
2nd item down
http://www.prostreetcustoms.net/CorvettePage.html
http://www.keislerauto.com/gm/transm...ette_84-88.asp
And if you really want a 6 speed I would recommend Richmonds T56 swap kit here.
http://store.summitracing.com/partde...5&autoview=sku
some more random info here
2nd item down
http://www.prostreetcustoms.net/CorvettePage.html
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by GIJoe
You only get rattles or "clutch chatter" if you convert to a single mass flywheel. If you have the stock dual mass, its as quiet as any other tranny.
I had a dual mass for many miles and 2 clutches. I converted to a single mass (and clutch 4 now) and it chatters like crazy in neutral... I was told that even before I had it installed... it doesn't bother the car, but it's a bit embarrasing sometimes when the chatter is noisier than the nice cam lope sound ...and you have to explain to people "umm theres nothing wrong with it, its just the ZF6 and a single mass flywheel"
i love mine though, but NOBODY wants to work on them, much less has anyone know what they are...they have like 3x the parts as any of the other trannies from what I understand.
They are rock solid though.
I had a dual mass for many miles and 2 clutches. I converted to a single mass (and clutch 4 now) and it chatters like crazy in neutral... I was told that even before I had it installed... it doesn't bother the car, but it's a bit embarrasing sometimes when the chatter is noisier than the nice cam lope sound ...and you have to explain to people "umm theres nothing wrong with it, its just the ZF6 and a single mass flywheel"
i love mine though, but NOBODY wants to work on them, much less has anyone know what they are...they have like 3x the parts as any of the other trannies from what I understand.
They are rock solid though.
Safety Car
Joined: Oct 2002
Posts: 3,991
Likes: 0
From: Phoenix AZ
Originally Posted by GRX
Dude, keep it a 4+3. I've gone from one to a Richmond 6spd and the gear noise made my vette sound like a diesel truck. This is something everyone failed to mention to me before the conversion. The richmond is more than rock solid but my car is a vette...not a racing car. I went back to the 4+3 (not an easy counter-conversion). Had the 4+3 rebuilt. Had the OD rebuilt. Now I enjoy the quiet of a sports car transmission. If and when I break it....I will have it rebuilt. Nothing lasts forever, and as most people willl bash this tranny, I PRAISE IT. Properly rebuilt, properly maintained, and most of all the linkage propertly lubed and ADJUSTED it will be a joy to drive. The 4 speed is basically the same as any other GM 4 speed out there. The OD should be disengaged when dueling.
Anybody want a a richmond 6spd with less than 150 miles on it? For sale. Whole kit.
Anybody want a a richmond 6spd with less than 150 miles on it? For sale. Whole kit.
Safety Car
Joined: Oct 2002
Posts: 3,991
Likes: 0
From: Phoenix AZ
Originally Posted by bogus
The Richmond 6spd is different from the T56...
he is referring to the old school Richmond 6spd. It's kinda like a Super T-10 with 2 more gears... the linkage is external and stuff.
he is referring to the old school Richmond 6spd. It's kinda like a Super T-10 with 2 more gears... the linkage is external and stuff.
Race Director
Joined: Jul 1999
Posts: 16,292
Likes: 104
From: Sun city CA
ZFs are noisy ?
Bogus said
I will warn you, the ZF is NOT a quiet gearbox. you will get idle rattles... but you might also get droning from the gearbox... it's a pain, really.
You may have had a noisy trans... it must be the exception, not the rule for the ZF box. My last 4 vettes have been black label ZFs ( the noisy ones as some have complained ) None of mine have ever been noisy till I ran an ORR with Redline in the trans... That made it noisy permanantly until it gets rebuilt !
I have replaced it with a blue label trans, the quieter of the 2 models due to gear angle... It sounds no different that my 100K mile 89 ZF daily driver...
BTW... I had a 4+3 back in 89... my only problem was losing the OD right after I bought it with 42K on it... Probably because the original owner never changed the fluid and filter.
IMHO the ZF is the better way to go if your motivated to work through the conversion process.
I will warn you, the ZF is NOT a quiet gearbox. you will get idle rattles... but you might also get droning from the gearbox... it's a pain, really.
You may have had a noisy trans... it must be the exception, not the rule for the ZF box. My last 4 vettes have been black label ZFs ( the noisy ones as some have complained ) None of mine have ever been noisy till I ran an ORR with Redline in the trans... That made it noisy permanantly until it gets rebuilt !
I have replaced it with a blue label trans, the quieter of the 2 models due to gear angle... It sounds no different that my 100K mile 89 ZF daily driver...
BTW... I had a 4+3 back in 89... my only problem was losing the OD right after I bought it with 42K on it... Probably because the original owner never changed the fluid and filter.
IMHO the ZF is the better way to go if your motivated to work through the conversion process.
