11 inch switch pitch

does any one have or know were i can buy a 11 inch switch pitch converter. they were in the small V8 and 6cyl

 

You'd be looking for one from an ST300.

Try the ususal ebay, craigslist, etc. or contact a transmission shop and see what their parts suppliers have.

 

the ST300 must have a 11 inch in the smaller engines and 12 inch in the 401-425, the 13 inch came in the 400 tranny, is this right ?

 

There were only two variable pitch converters I've ever heard of...the ST300 got the 12", the ST400, 13".

Devon

 

My information has it that the ST400 has the 12" converter and the ST300 has the 11" converter.

 

Well if it helps, I have a 12" converter from a '67 ST300 in my modified TH400 now. I have two 13" converters from '67 ST400's under the bench.

To see the actual measurements, check out http://www.v8buick.com/showthread.php?t=143723 .

Devon

 

Contact Jim Weise. Doesn't he build SP converters at TSP?

 

thanks, i do have the 12 inch now. thought there was a 11 inch out there

 

Thanks for the info Larry!

 

looking at the thread you posted there all the same size on the out side, great info thanks

 

Take another look...the 13" measures a bit over 13", the 12" is just a bit over 12". There's still an inch of difference between the two outside diameters.

Viewing at an angle is confusing, that's why Jim set up straight edges for the tape measure.

Devon

 

sorry i ment to say the 12 inch V6 and the 12 inch V8 are both the same size.

 

Gotcha.

Devon

 

I actually had a guy from out west bring me about 10 cores here last summer.. I probably have about half a dozen left. I try to keep one built and ready to go all the time here.

As far as the v-6 and V-8 12" converters, it does not matter which one we start with, as the only difference between the two was the stator fin angle, the factory altered the hi stall stop to make the V-6 one stall higher.

We take that modification to it's max, while still maintaining converter function, this typically provides a 3000 to 3200 stall in high, behind a big block in a heavy car.

We don't fuss with the low stall blade angle, as 16-1800 is about right for most street type performance cams, allows just enough looseness to soak up cam lope.

We do hand braze the fins in the pump and turbine. The converters are actually very strong as designed by GM, and I can honestly say I have never had one of mine fail, that I am aware of.

I got a call just yesterday from a guy who had gone thru a couple Poston units, and was questioning if they were strong enough to go behind a 550 HP motor in a GS.

The answer of course is yes, I have serveral running around in that type of car.

JW

 

got a whole st300 from a 66 for sale in