Shift kit for Switch pitch Turbo 400?

I'll get to the point first, so you don't have to read all the background to figure it out: does anyone make a shift improver kit for a '67 Switch Pitch Super Turbine?

I have a '67 Riviera GS. It's got 114,000 miles on it. It looks like someone maintained it well and the trans fluid looks good. It's bone stock and the switch pitch works fine. Transmission shifts well, but as you know, the factory shifts leave a little to be desired. I'd like to leave the trans in the car and just do a shift kit, fluid change, and add an oil cooler. I'm not looking for drag strip style shifts, just what we used to call the "heavy duty" setting. I'm hoping to get another 100k out of the trans and I think firmer shifts would help.

In the past, I've had cars with Turbo 350s. I'd just get a $35.00 shift kit, drop the pan and valve body, follow the directions, and put it back together. Worked great. Finding someone who can tell me what kit to get is not as easy for this car as I thought. I've read some SP articles on-line and seen what looks to be a minor difference in the valve body. Sure would be nice to know what I'm getting into before I have it apart.

I called up TransGo and he said that due to the valve body differences between the SP and the normal Turbo 400, that there wasn't a kit for it, but that pieces from two kits could be used along with some hole-drilling. He said he'd have to "walk me through it". When I asked if it would give me firmer shifts, he said that it would "clean-up" the shift, but stopped short of saying it would be firmer.

Being somewhat dissatisfied with how coy TransGo was being, I called B&M. I got what sounded like a very young guy on the phone. He read from the catalog that they make a shift kit for a '67 Riviera. When I started asking him about variable-pitch torque converters and corresponding valve bodies, he got nervous and said they don't make anything for that. I might call back in a couple of days and see if I get someone else.

Can anyone tell if there is a "shift kit" for my trans and which one it is? Thanks in advance...

 

The dude from Trans go is right - the "kit" is generally just a new valve body plate with larger clutch apply feeds, etc...then some instructions to remove checkballs, etc...some common gaskets...I think the most critical part of any kit is the instructions and "map".

So that said, I'd think you could do the same thing on your ST400 with no kit at all, basically. Just check fluid routing in a shop manual.

If you really wanted to change shift quality, you'd need to change the clutch and plate configuration.....more clutches (6-7?), quality parts (Red Eagle, Kolene, etc..) That's one common approach anyway. You could also modify line pressure by shimming the pump relief valve. While you're in there, replace the OEM sprag with a quality aftermarket unit.

One idea that I haven't played with yet is a later style valve body from a 71-76 B-Body....read about that here:http://www.buickperformanceclub.com/SPTrans.htm Be sure to find a 90's chevy truck deep pan and pickup!

So when you're done with all that, wire in a Bruce Roe electronic control unit set up the way you like it (mine is modified to default to low stall after brake release, unless full throttle timer is engaged)

I am not a transmission guy, but I do have two good running switch pitch cars, so this is a good starting point to build a trans that will amaze you every day. Don't try to just limp this one along... be bold!

Guys - am I missing anything?

 

agree 100%. honestly when I read "I am not a transmission guy,but..." I was expecting a " but I did stay at a holiday inn express last night. I used the trans go HD2 and red eagle clutches on my 4L80e. My professional builder agreed with many here on the board. Trans go is a quality product.

 

OK - thanks for all the input. Between what you guys have said and what I've been reading it's all starting to make sense.

I thought I was clear with the TransGo guy that I had a '67, but he sent me an extra file (attached) that's for the '64-only trans.

 

I like the way you think, and I'm prone to tearing stuff apart to do it right, but I've got two other projects going right now and I just want to be able to cruiser around in the Riv next summer.

The engine has 114k and runs pretty good. It'll probably need a rebuild soon enough. At that time the trans would come out for a good going over.

So, in the meantime, I just want to throw the shift kit in. And fix the gaping cracks in the exhaust manifolds (thanks for the headers TA!). And maybe get the mouse smell out...

 

I read the Switch Pitch transmissions are missing a downshift valve that you may or may not
have noticed. You could just put on a valve body & plate from a car with good shifting, say a
Pontiac which never had SWP. Then the shift kit of your choice has no issue. Of course the
SWP function isn't tied to the valve body.

I wouldn't ever rebuild an engine till it shows signs of wear: blow by, oil use, or bad sounds.
Do replace the timing chain. Most of the trouble I have with engines is from rebuilts. An
original trans though could be ready to blow some seals and burn up; some of the rubber I
remove is so hard that it cracks when bent. Some is shredding. good luck, Bruce Roe

 

Indeed. Thanks for the tip on the timing chain. Maybe I'll do that, put in electronic ignition, and give the carb a good going through and leave it alone until something goes bad.

Hmmmm.I'll have to look at the xmsn more closely. Maybe put a new rear seal in too.

 

+2 on the rebuild - in your case check oil pressure too, hook up a gauge and drive around. if it's not where it needs to be, at least the pump is external. Run some GM Top Engine Cleaner through it and check compression. I'd be willing to bet that engine has another 50k in it...

Good luck!

 

Where's the best place to hook the gauge in? Is the stock one mechanical and I just "T" in?

If the stock gauge is any indication, the oil pressure isumquestionable. Takes a little while to come up when starting too.

 

The Trans Go 400 1-2 kit is what you want. It has a special dual passage separator plate in it, which utilizes both apply areas of the direct clutch, which is the weak point in the 400 friction system.

You tailor the clutch apply hole sizes in the plate for your application, and I would be glad to suggest some sizes for you. Also, you can alter the 1/2 accumulator operation via springs included in the kit.

I have a complete recipe for the 400 for your application, that I have built many times. I would be glad to share it with you.

As long as the rubber seals in your trans are still serviceable, you should be able to achieve satisfactory results with a shift kit.

If the trans has "morning sickness" in which it takes a longer than normal time to shift into gear, especially when it's colder out, then you should just consider a trans rebuild, the seals need to be replaced, and the shift kit/modifications can be done at that time.

I do also recommend upgrading that trans to the later valve body/oil pan/filter-pickup tube style, to gain the 3-2 modulated part throttle downshift, as well as make parts easier to find for normal filter maintenance.

 

Stock sender location is fine for testing.

You can simply temporarily substitute a mechanical gauge, for the stock electric one, to verify the stock gauge readings.

Although what your describing is absolutely normal for a BBB with over 100K on it. They were only designed when new to have 45psi oil pressure, and vitually all of them have low oil pressure at idle. This is very common, and not necessarily a huge cause for concern. I might recommend calling TA performance, and getting a new timing cover/oil pump assembly, to install when you do your timing chain maintenance. In face, you can get all the parts from them, for one stop shopping.

This will insure that your have a good oil pump on the motor, you will see improved driving and idling oil pressures, and it will help prolong the life of your stock engine.

Good luck with it.

JW

 

Wow - that would be great. Yes please and thank you. (I have a 3.42 rear if that factors in at all).

It shifts into gear promptly, even when cold out. Part-throttle shifts are excellent, but the full-throttle 2-3 shift is "vague".

I have an aluminum pan coming so I can upgrade to the later filter when I do the shift kit. I will probably stick with the current valve body for now and keep my eyes peeled for a newer valve body. Will any later valve body work?

 

You guys on this forum are dangerous and will have me rebuilding the engine around the block while I keep it in the chassis! :grin:

 

Yep, but you won't get better advise anywhere else in the world. Folks here are the best there is. :TU:

 

You make it sound like ordering wine. "Garcon - bring me something special. Perhaps a valve body from the Oldsmobile vineyard, of the '71 vintage." :grin:

 

Thanks Larry. I found that article when I first started searching the net about switch-pitch transmissions. It's what got me questioning how to shift kit one. :TU: