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Your advice

Your advice

  • Leave it original

    Votes: 5 31.3%
  • The swap would not hurt the value

    Votes: 0 0.0%
  • Richmond 6 speed

    Votes: 1 6.3%
  • ZF 6 speed

    Votes: 10 62.5%

  • Total voters
    16

8388

Well-known member
Joined
Jan 2, 2003
Messages
808
Location
Texas
Corvette
(2) Callaway's (2) ZR1 (1) supercharged 35th
Like to know what you guys think. The overdrive in my 88 Callaway TT has failed. The 4+3 is really not designed for the power a TT makes. You can baby drive the car, but eventually with enough power it will fail again.

My poll question is : who thinks that by swapping in a Richmond 6 speed or a ZF 6 speed on a Callaway, would eventually cause the value of the car to drop. These are collectables cars, and sometimes, if everything is not original the value suffers. Do you guys think this would be the case here ? Would this be a turn off when considering to buy a Callaway ?

The Richmond requires some tunnel modifications and the shifter area will look slightly different, but on the other hand 5th is 1 to 1 and 6th is a slight overdrive, this might improve how quick the car can achieve top speed.
 
If you REALLY want to re-sell it for the appreciated value, you'll need to put the 4+3 back on, but you know it will fail....

If you're going to drive it and enjoy it, put on something that you'll enjoy.

Try to get one that you can swap back for a 4+3 before you sell the car so it will be in "original condition" or whatever makes it worth more $$$. I think that'll work.

Mike
 
ediconu said:
If you REALLY want to re-sell it for the appreciated value, you'll need to put the 4+3 back on, but you know it will fail....

If you're going to drive it and enjoy it, put on something that you'll enjoy.

Try to get one that you can swap back for a 4+3 before you sell the car so it will be in "original condition" or whatever makes it worth more $$$. I think that'll work.

Mike

Ditto. Drive it with a ZF6 and be able to "retreat" to the 4+3 to sell.

HoldHard
 
A future owner would probably appreciate a ZF6 upgrade. The trans tunnel area where the 4+3 shifter is located gets heavily modified when the ZF goes in... so, putting the 4+3 back in is do-able.. but the area surrounding some of the 4+3 linkage is going to be ugly!
 
Sam,

If you are not condidering keeping this car stock and want it to literally kick the pants off everything that comes its way from a stop to 180+....... TH400 with a Gear Vendors OD on your current 3.07 rear will do it.. Use a good converter with a manual lock up and a stall about 2400, like that Vigalante.. If they make it for the 400. You would probably create the quickest callaway around this way. I know my 89 would gain a second+ in a drag race if I did not have to shift it and the car could be lanched under boost and the car could stay under boost between shifts... The biggest loss of the race is having to let off the major power, go to the next gear, and then let it build up again.. This setup will eliminate that for you and if I remember right, these are 10 second cars with these automatics and very basic things done to them.....

I know you will lose a bit on the top and from certain speeds, but for a thing like the flying mile... This combination would rule and be 100% consistant and easier on everthing including the driver..... It would be easier than a 6 speed swap, it would also be correct for a callaway of that year as callaway took 4+3 cars and made them TH400/OD automatics... They never used the automatic car as it was too little hardware in them as you are aware and they wanted to start with the good stuff.......

To tell you what I would do... If I have any trouble with my 88 4+3 callaway, that I never drive, I will probably put a TH400/OD setup in it as it would make the car so much more fun and I would do it like the car was built that way originally from callaway.. This was a 10K option on these cars as you know to have the TH400/OD and I think its a good addition to the car over a ZF swap.... Now I would not do this on my 89 as it is a 6 speed already.

If not, I would keep it all original 4+3 and rebuld the OD as its a whole lot less headache than swapping anything and the OD's are bulletproof once SK does them.... Even the sledghammer has a 4+3 OD unit behing a DNE 5 speed at one point in its life. The trans is more than strong enough for your power if the OD is built right. I have never had an issue with an SK built OD. The 6 speed is nice an definatly a better driving trans over a 4+3, but its a bunch of different things to change and is not correct for that year.... It will also not make you any faster than the 4+3 no matter what you think, and at certains speeds slower do the the messed up OD ratios. You will definatly have to change the rear gears on the car to at least a 3:31-3:45 also due to the gearing of the ZF or you will have a messed up wide ratio of shifting. One thing for sure is will definatly have to spend a bunch of money on a clutch as the ZF clutches suck, and even my high dollar Spec4 on my 89 has issues... Aftermarket BS. The 4+3 clutches are no problem.... If you keep it original, just have that OD built with the .68 Z51 ratio, not the .60 like you have now when you send it to SK.
 
Well, I spoke with Brian at S-K Speed, and they recently started to offer some bronze clutches, which are by far much stronger than the previous clutches. You have to modify a few other things inside the unit, but the word is these will take a lot more punishment. I need to tear into the unit I currently have to see if it has ever received the upgraded clutch pack, before I can order all the parts for rebuilding.

I was always interested in keeping this car original, so I think for now I'm gonna go with these new clutches and see how it works out. What scares me of course, is the fact that I may end up discovering a new weak link. The super T10 along the ZF, T56, and Richmond 6 speed are all rated about the same, 450 ft. lbs of torque. I plan on re-doing the cooler lines aswell as adding another cooler inline, this should help with the much needed cooling of the OD unit.

The Th400 with a gear vendors OD unit is not a bad idea, but I enjoy manually shifting these cars too much.
 
as I am sure you would do anyways, save all original parts...

Im my opinion, changing (upgrading) to a ZF6, if done in a professional manner - again, I am sure you would :) that would be a benefit to yourslf while owning it and a "plus" for a potential buyer as many wish for a 6 speed -vs- the 4+3 DN od unit found in 87 / 88 B2K's.

Let us know what you decide :beer
 
Sam,

I agree with Ultra. Despite the it not being original for that year car, there is value in an upgrade especially in this case where it enhances the Callaway mods (reliability & performance).

However, if you go the route of the ZF6 then you have the added benefit of claiming that the 90+ Callaway Twin Turbo's had a ZF6 and that you merely were bringing up to current specs. Heck, I see it the same as getting the 475HP upgrade, Center exhaust, Aerobody, etc.

Good Luck and Best Wishes!

-Luigi
:cool
 
*89x2* said:
would be a benefit to yourslf while owning it and a "plus" for a potential buyer as many wish for a 6 speed -vs- the 4+3 DN od unit found in 87 / 88 B2K's.


I agree completely.
 
8388 said:
Well, I spoke with Brian at S-K Speed, and they recently started to offer some bronze clutches, which are by far much stronger than the previous clutches. You have to modify a few other things inside the unit, but the word is these will take a lot more punishment. I need to tear into the unit I currently have to see if it has ever received the upgraded clutch pack, before I can order all the parts for rebuilding.

I was always interested in keeping this car original, so I think for now I'm gonna go with these new clutches and see how it works out. What scares me of course, is the fact that I may end up discovering a new weak link. The super T10 along the ZF, T56, and Richmond 6 speed are all rated about the same, 450 ft. lbs of torque. I plan on re-doing the cooler lines aswell as adding another cooler inline, this should help with the much needed cooling of the OD unit.

The Th400 with a gear vendors OD unit is not a bad idea, but I enjoy manually shifting these cars too much.

Why not just send the whole unit to SK and let them do it, since they seem to have lots of experience with these trannys. That way you can be pretty sure that it's done right, and everything is put in correctly.. Sounds like it will save a lot of headache in the future of removing/replacing because something isn't right... I'd crate that thing up and send it over instead of having some local fly by night do it.

jmho
 
929RR said:
I'd crate that thing up and send it over instead of having some local fly by night do it.

jmho

If this was a car I was planning on selling, I would send it in, but I plan on keeping this car a long time and this will probably not be the last time I'll have to rebuild it.

Only reason I may send it in, is if I can't convert this .60 to a .68 overdrive, otherwise this overdrive aint going anywhere. This is a piece of cake compared to a 700 r4. I think I can handle it ;)


BTW the best way to learn is to do it yourself:)
 
I appreciate all the advice given, but I have decided to keep it a 4+3. Converting to a ZF is definitely the way to go, and if cutting up the tunnel weren't necessary it would be a done deal. I don't mind modifying a collectable car so long as the modifications could be undone and the car brought back to it's original state. Cutting up the tunnel would be too permanent, and I'm afraid years from now having it all original will make all the difference in the world. We can see that, by looking at the history of collectable cars.

Luckily for me, my 91 Callaway is a 6 speed.

This type of conversation is very useful as we try to figure out what mods may or may not help the value of our cars.:beer
 
8388 said:
This type of conversation is very useful as we try to figure out what mods may or may not help the value of our cars.:beer

Sam, I agree 110% Although I think the ZF swap is beneficial to you and any future owner (when done right) I can name dozens of things I have seen that were just plain wrong on Callaways - Most have to do w/ exterior - Wheel chioces and such...


This one here has to be one of the worst... :(

It's bad:


Would the Richmond 6 spd fit right in???
 
The richmond would go in, but after having one in on of my cars, its best suited for a total race car as its a noisy hard shifting trans... If you think the 4+3 is clunky add 50% more to it and you have the richmond 6 speed. If he wanted to make a hot rod out of it, that would be a great choice and the richmond is a great total hot rod trans with no reguard for integrity or creature comfort... Its pretty damn annoying if you get my point....

I also dont think the ZF would hurt the value of the car as a whole and would be a great and logical swap.... I have raced 4+3's possibly harder than most having two 88 cars with them, and also a brand new spare in the attic... I have pulled them and worked on them more times that I care to count. both SK modified. Once you build the OD right, there is no problem and for racing top speed... The 4+3 puts the car in more desirable ratios with the 3:08 rear and the .68 over anything the ZF offers... The Sledghammer made its record run with a 4+3 OD behind a DNE 5 speed... It would have done the same had the transmission been a 4+3 4 speed as th e DND 5 speed is a 1:1 5th.

I much rather cruise around town with a ZF over a 4+3 and a ZF is definatly easier to race... The 4+3 is not bad though once you understand it and is unfortunatly original to the cars. I think Sams few miles that he puts on his car, fixing the 4+3 is really the right choice and keeping the car original as possible...

Now for racing... Make that sucker a TH400 with an OD, and he would own just about everything from a stop to 150+. This combo would also be correct for the car too and there are no "RPO" codes that would ever tell different as the autos were 4+3 cars... The only way to tell that it was not an original automatic is with callaways documentation, and we all know that is not perfect.

The biggest killer of a turbo car in acceleration is the loss of boost between shifts... Especially one like the callaway that takes a bit to spool up..
 
Sam,

Please tell me about these bronze clutches for the overdrive that SK is offering now. What else has to be modified?

I have the original T10 being rebuilt right now. 1st gear and the countershaft lost a few teeth as well as the 2nd synchro being burned up. I also have a 0.60 overdrive with burned clutch packs being rebuilt immediately after it. If putting these in is something that can be done other than by SK I'd like to look at that option.

Once that tranny is redone I'm putting it into the car with a Mcleod street twin clutch and will then rebuild the current one in the car (popping out of 2nd) which has the 0.68 overdrive.

FWIW the 'CC' ratios in the T10 are only rated to 300 ft/lb I believe.

Thank you.
 
Hey Scorp. I talked to Brian at SK last Tuesday, and he mentioned the bronze clutches. I'm not sure what all is needed to be modified yet, but he let me to believe thats it's not that difficult. If you have experience rebuilding auto tranny it's no biggy from what he tells me. I will find out more about what's involved once I get ready to order. He did say that once this mod is applied, one has to be careful how they shift cause it's brutal.

When you talk to SK they do mention that they are not too pleased with the ZF 6 speed, infact he claims to see more of them with repair issues, and as some of us know they are not cheap to rebuild. I guess it depends on who you talk to about the torque ratings. Years ago I built a pretty strong pontiac 400 for a 79 10th anniversary T/A which used the super T-10 and never had any problems and this was even with some juice, and that was an easy 3800 lbs car that was punished racing back in the hay day in Dallas when racing was almost on a nitely basis.

I'll keep posting more info as I learn a bit more about what all is involved.
Good luck with your project.
-SAM-
 
Thanks, Sam, I look forward to the updates. I'll never fully understand how these torque ratings work when we're all making more than they "say" should be given to them. :)
 
I have decided to keep it a 4+3.

I think you made a good decesion. I had a 4+3 in my 86 and actually liked it. However once I added the NOS:_rock I had many problems with it. This is one of the reasons I looked for a 6speed Callaway. I may be in the minority, but I would have less of a problem buying a Callaway with a NASH then I would buying one that was changed over to something that was not correct of the car.

Cross
 

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