I have a stock 66 Skylark with 300/2 and the stock two speed switch pitch transmission. I cannot get this thing to kickdown unless it is manually pulled down into low. Starts out in low, upshifts fine, but then won't kickdown, no passing gear at all. Also, if the two speed torque converter is working, I can't feel it. To date I have adjusted the transmission linkage on the carb/manifold per the Buick repair manual, with no results. Other than this car being "dog" slow it runs great and I would like to find out how to get a little more peppy performance. I'm still new to this Buick thing, so bear with me if I have mis-named some off the technical items. Thanks
Check fuses. If they're ok, check for presence of 12V at the trans when the switch next to the carb (left side) is engaged...2/3 throttle should get high stall, around 3/4 should get detent (downshift). It may be as simple as a fuse or loose electrical connector...and don't dismiss the smaller connector on the pedal linage near the firewall. http://home.comcast.net/~shinzan/ST300_linkage.jpg Devon
Excellent! I'll start looking tonight. I've got a few of those old car electrical problems, like dash lights come on when shifting into reverse, so it just might turn out to be gremlins or fuses. Thank you for the help.
If I remember correctly, there are two wires going down to transmission connector. One is kickdown, the other switch pitch. Check with 12V trouble light to see if both come on, kickdown at near full throttle, switch pitch at 60% (2/3) throttle. :3gears:
No, no invisible font, just thought he might check at actual connector on transmission. No harm done.:spank: Dude has enough issues with dash lights coming on in reverse. Maybe FOMOCO wired it! (They used to have backup lights only come on with taillights on. At least you had to be in reverse.) Hey could his problem be bad grounds in the taillight/backup light assemblies that feed the headlight switch from the backup light wires, through the backup light filaments to taillight wires to the dash lights? Hmmm, no charge for the free diagnosis. :beer
daWildcat and d2willys really know their stuff about the SP transmission. I got to work on it last night, and guess what I found halfway down on the bellhousing was a plug. You guessed it, the plug had pulled out somehow eons ago and was just hanging there looking for something to do. I tested the contacts for juice at 2/3 and full throttle and sure enough, there was power. I hooked it up and will road test it this weekend. Maybe this pooch will run a little peppier after that. Also, the wiper fuse does control the power to the kickdown switch. Fellows, thanks again, this old Buick is always a surprise! Now all I have to do is find out why the dash light come on when I shift into reverse. Many thanks
Hey could the problem be bad grounds in the taillight/backup light assemblies that feed the headlight switch from the backup light wires, through the backup light filaments to taillight wires to the dash lights? Hmmm, no charge for the free diagnosis.:sleep: BTW: Thanks for the compliment. Have fun with the SP, it will definitely be different than a standard pitch automatic.
Ok, here's the up date--sea trialed the car (road test) Sunday morning. I got downshift for passing gears, never had that before and it seems a little better off the line. One question, at 70 she's still in passing, I got out of it over age concerns of the gear, then it upshifted fine. How fast will this critter go in passing? Lastly, as to the faulty wiring, well if you plug in the license plate light into the reverse light socket (they fit), and plug that reverse light socket into the license plate socket, you get automatic dash lights in reverse! Changed things back the way they should be and all is well. Thanks again.
Depending on the rear axle's gear ratio, it's not surprising that it's staying in 1st gear while your foot is in it at 70 mph. The service manual says you'll likely get passing gear (1st) when you floor it below 60 mph. Do you have a tachometer installed? It would be good to know the rpm at 70 so I can get a feel for when your WOT upshift should occur. Devon
Nice job on both the trans wiring and the light issue. But don't you like your dash lights coming on in reverse, a new twist.o No: Some older Powerglides would go over 70 before upshifting to drive. I would think the ST300 could do that too. If you have a numerically low back end then 70 would come pretty fast and the engine might still have something left.:beer
I'm sleepless in Seattle right now, so I can't get to the spec sheet for the car, but seems like it has a 2.67:1 rear. My wife gave me a brand new Sun tach, in the box, original from the 70's that she found during one of her frequent trips to Goodwill. I just haven't has the heart to take it out of the box and put it on. It's such a time trip to look at it all original and everything. One thing, at 70 in low it does have a sort of drumming noise that it doesn't have at 70-80 in drive. Could be the start of something bad and that's why I got out of it. Thanks again
Dont want to hi-jack this but I've been looking at this issue in advance of using a SP in my Range Rover http://www.buickperformance.com/SPTrans.htm Think this explains why you have the problem with no kick-down. Basically the SP is not designed to allow that. On the back of this I assume that a shift kit would solve this issue???
The problem has been corrected, see the posts above!:spank: You may have to either raise the rear end ratio up a bit, which will give you more get up and go, but reduce the max upshift speed, or change the governor weights a tad. When adjusting the governor weights you may have to play with the vacuum modulator adjustement for desired mid throttle shifts.:Brow:
Rossco: I am sorry if I hurt your feelings, but the information in the quote is not accurate, particularly the part about "Basically the SP is not designed to allow that." This sounds as if any SP transmission is not designed to be kicked down, it is. Now the SP400 transmissions did not have a 3-2 shift valve and this would not allow part throttle 3-2 downshifts, but had no affect on wot kickdowns. This is why using newer valve bodies are better as they have the 3-2 valve and circuits.:rant: The article mentioned is very good!:gp: Again, sorry!
That is correct. Read the article Rossco. The SP valvebody only allows a full throttle downshift. It will also short shift 2-3 regardless of governor modification. I learned this the hard way.
