It looks like i wont be able to use the switch pitch set up in my car as it wont fit in the ultra bell trans. The 11" converter that i am not pleased with fits, the 12" wont fit. I have to go with a dreaded fixed pitch converter. I'm thinking about selling it all to help fund the fixed pitch setup? Any suggestions?
GM never made an 11" SP converter, only 12" or 13" The 11" i am using now is rated 2000/4400. I i do get 2100 on the foot brake and 4000 on the transbrake in high mode. However it seems that once i turn up the boost the 4000 turns into 5000, and the car feels like its out of its torque band and just reving, unless i have some othere issue inside the trans its too hard to tell , without swaping to another converter. I really need to try a 1800/3200 or so,but i need to find one in a custom made 11" core. I am working with PAE to sort it all out, but summer is short and want to drive the car also, so time is of the essence. I could see my combo making 560+ RWHP easliy.
That sucks bro...........I would try one more time with a restall on the current converter before swapping it out. If not contact Coan/ATI/BTE and tell them what you have. I know BTE makes an 9.5" Turbo/Supercharger converter thats supposed to be pretty nice. Said to be flash about 4200-4500 but pretty tight on cruise.
I am trying to get another ultrabell, maybe the newer ones are made bigger, im waiting for JW to get back to me. I really don;t want to loose the SP just yet.
My suggestion as a former BTE customer and transmission builder is to not buy BTE. If they can't get the stall right(or even close) on a mild street 427 BBC in a Chevelle, they probably aren't going to get it right on a boosted application. ATI and Coan are good suggestions, I recommend PTC to most of my customers. One friend of mine uses Edge converters and they seem to work well also.
I have the front pump all apart and preparing to put in a stock th350 converter. ANyone know what would be the diamter the converter would be from a turbo 350 a few years before the lockup 350 came out? This is really alot of hard work on the floor with the gear vendors attached, in and out all the time. I hope no one else has to go through this...
Well, not really given up but, i wonder if my valvebody in my tranny has some mod in it that is causing the sp not to work correctly. Since that 12" t350 converter won;t fit i have no way of testing the sp again, unless i find another BOP 400 around. I found a used PTC 9.5" converter i am giong to try and see how that one works.
My info and Kenne-Bell's is that the SP-300 and SP400(Big block) used 13" but the small block version of the SP-300 used an 11".
Here is the one file I have with that info, but I do know that the Jetaway (SP-300) in 66 330 V8 Oldsmobiles ran 11".
GM made three S/P converters. Two 12" units and a 13" unit. The 12" units were called GM-1 & GM-2. The GM-1 was for V-6 applications, the GM-2 was for the 300/340 V-8 applications, all with the ST-300 2 speed trans. The GM-4 was the 13" for any of the full size cars using the ST-400 trans. The GM-3 was a fixed pitch converter using the TH-400 trans. The quoted article was incorrect.
Interesting. I took a look in my parts book and found four distinct part numbers for ST300 VP converters for whatever reason: '64-'67 V6 '64-'66 V8 except GS '65-'66 GS '67 V8 The PAE units may be Frankensteins like the KB units, so I wouldn't count on them representing stock applications... o No: Devon
The st 300 converter is a 12" unit and will not fit in a JW ultrabell period. I have heard many good things about the PTC converter. Slippage under 5% at wot is proven by a few datalogs from a friends 9 sec car. Art carr 9" converter range 8-10% slip im told.
