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  #31 (permalink)  
Old 10-30-2013, 06:28 PM
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Thanks again dwwl, The pressures I posted were before, during and after a 15 mile road test. I did verify pressures before the drive last night, then again this morning. I got on line today and spoke with people at B&M and TCI. B&M wont sell their high rate PR spring without the whole $80+ kit. TCI does sell their purple spring separate and says that it will raise base pressure 15-20psi over the Transgo green spring. That is a step in the right direction at least. I'm also going to go with the .570 boost and .400 low/rev boost valves from TCI. If the trans shifts a little hard, I don't care. It is a Beasty hotrod after all not a luxury sedan.

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  #32 (permalink)  
Old 10-31-2013, 06:40 AM
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I either need a new old laptop or to fix this one. I tried to watch virtual dash on my ACCEL DFI on the way home last night for clues to why my TCC isn't working but the backlight on my old Gateway laptop has bit the dust and I can hardly see the screen. It was a $50 CL buy three years ago so I guess I got my $ worth. The thing that sucks about technology is that as it progresses, the old gets left behind. The software for my early DFI has to run on a laptop running Windows 98 or 95. That means old laptop. These suckers are getting hard to find and they are generally beat when I find them. Maybe I can fix this one. Could just be a capacitor. I hate to buy a new DFI system just because this one isn't supported well anymore. The gen 6 is old school and it works fine.

In any case, my TCC is not working. I have the parameters set as follows. Minimum throttle-15%, minimum rpm- 1,500, TBD(torque before disengage, think vacuum switch)- .70 bar. I know that my engine idles at .72 because of the big cam but it's got to be getting below .70 at cruise. Guess I could try setting TBD at .75 bar to see if it makes a difference. I think I saw .72 as I was driving last night but not sure.

For now I am letting it sit (warm and safe in my garage) to spend some time at home before my wife and dogs forget who I am. I don't want to get bit or shot coming in late one night. It's so hard to put the car to bed when everything isn't perfect. Next week or whenever I get a free day, I'll connect my Power Probe to the power and ground circuits of the solenoid and verify control signal. I can measure resistance of the solenoid coil through the circuit from the connector also. It almost has to be either a bad solenoid or a crappy connection since it doesn't work at all, either in 3rd with the selector switch on or in 4th. I did verify ground at pin D with my selector switch on.

I will not again make the mistake of driving it for any distance without the TCC working. I know now that it was heat from the converter not locking, the poor cooler system I used to have, and rush hour traffic on a 95 degree July day that smoked the trans last time.
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Old 10-31-2013, 10:14 AM
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I read somewhere, (and it may of been for the 200 4r and not the 700 r4) that if you use to big of valves, you can have a problem with the second gear band not fully releasing. I know I read that someone had used the bigger valves and had the felling that something was dragging. They contributed their second gear band failure was caused by it. the cure was to shim up the second gear servo piston spring a few thousands because the spring wasn't designed strong enough. I don't know if that makes sense to you. It had something to do with the pressures being to high and the spring not capable of overcoming that much added pressure. Though I would mention it to you, incase you would get that felling something is holding or dragging. I would give it a shot and see.
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  #34 (permalink)  
Old 10-31-2013, 11:06 AM
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Thanks for the tip on the big boost valves. Just have to see how they work I guess. The one thing I have heard from people running the large valves is that they produce very firm shifts. One guy said he wouldn't be sure about running them with any less than 3,500 stall. I'm right there now. He was running them with a 4,500 stall and seeing 300psi full TV. I suppose if my head gets ripped loose from my shoulders from 1st to 2nd, I'll just need to wear a neck brace from now on. It seems like 250 max pressure that I'm getting now is fine. 270 or 280 would be better. I'm really just looking for more base line pressure from the spring change. I figure the larger valves will also give quicker line rise which can't hurt. I really like that there is no leveling off or drop at high throttle opening with the line bias valve blocked. Thank you Crosley.

Right now I'm reeling a little over the price of the .400 low/rev valve. I thought maybe there was an error or something that Summit had it listed for $53 and change. Then I looked for it at Jeg's and they have it for $75. That thing must be made of unobtanium at that price. I am still going to get the whole set of spring and both valves to try out. I mean it's only money and what's money when it comes to satisfying my obsession.
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  #35 (permalink)  
Old 10-31-2013, 11:17 AM
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I was going to say that I've actually noticed the 1-2 shift is a little softer with the shift kit. I run the wide band and big Superior 2nd servo. Before the kit, the shift wasn't harsh at low throttle just firm and at full throttle it was very firm. Now it is more like a normal trans at light throttle, low speed, then at more than half throttle it is good and firm. I don't know if I like the soft shift at light throttle. I suppose it won't hurt anything and it could also just be the high stall converter absorbing the shift shock. Plus this converter is the lighter 9.5" which is sure to create less gear train shock than the 12" did. The big valves and stiffer PR spring will probably firm it up anyway. We'll see.
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  #36 (permalink)  
Old 10-31-2013, 11:49 AM
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I'm thinking your right on the shift feeling softer at light throttle with the higher stall because the torque convertor is now absorbing some of it. Have fun with your toy. And your right, you might as well spend it. My kids told me to, or they would after i'm gone.
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  #37 (permalink)  
Old 10-31-2013, 01:39 PM
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Lol! Yeah. My son gets the car when I kick it, so this is kind of an investment for his sake too.
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  #38 (permalink)  
Old 11-06-2013, 01:47 PM
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I was thinking about the soft 1-2 shift I'm getting at light throttle. There is nothing I did in the shift kit that should have affected the 1-2 shift. I didn't do the Transgo 2nd accumulator spring change that came with the kit. It's the same setup as used with the 700Jr shift kit. I like the 1-2 shift Ive had since the build last year so I just used the same heavy brown spring I had in there before. What I did change though was the 2nd accumulator itself. Pro Built includes a new small pin 2nd accumulator with the kit so I used it. This morning I was looking at the left over seals(factory 2nd servo seal kit that my unit no longer takes). I noticed the 2nd accumulator piston seal in the bag. I bet that Dana just put the piston in the housing for shipping without the seal installed. That would certainly cause a soft shift at light throttle. Duh. I still have my old accumulator too and it's in fine shape. Either way, I'll install the seal or just swap back to the old piece when I do the PR spring and boost valve swap in the next month or so. I still have to get the TCC working too. I'll test the circuit in the next few weeks for an open and verify voltage and ground to the solenoid. It may just be a junk solenoid. I'll have one on hand when I drop the pan if things look that way after testing.

I also got in touch with Chris at Oregon Torque Converter about the pump I used in this build. Ken who does the pumps is off at SEMA but I can talk to him next week. Chris is pretty sure that Ken sets clearances in the pumps before he ships them. It will be nice to know that I'm good on the pump.

Raining now so the car is in the garage and probably will stay there until spring, aside from a trip or two to the the shop while I dial in the trans. I am anxious to get the trans all squared away so it will be solid for next season.
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  #39 (permalink)  
Old 11-06-2013, 03:54 PM
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Aren't these tranny so much fun.?!!?. Just got my problem resolved with my tranny fluid being low while hot, and high after sitting a few days. My problem was that If I had the fluid at the full mark when running hot, when shut of, the fluid from my two external coolers would bleed back into the pan. I solved the problem by lowering the two coolers so they are the same height as the top of my pan.
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  #40 (permalink)  
Old 11-07-2013, 02:33 PM
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I've noticed before that the fluid level in most automatics rises quite a bit when sitting. Try sometime, on any automatic trans, replacing the fill tube seal without first draining the fluid. You get a good three or so quarts draining out of the tube hole. This is way above the running full mark. I understand this to be caused by fluid draining back from the converter, clutches, and gear train. I suppose having the cooler above the trans makes it more of an issue.

On trucks that tow heavy loads, we used to install large fluid coolers with fans just under the front of the bed. This is higher than the transmission. It never caused a problem. As long as fluid doesn't run out the vent, I think you're fine.
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  #41 (permalink)  
Old 11-10-2013, 04:32 AM
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Originally Posted by ASE Doc View Post
Thanks again dwwl, The pressures I posted were before, during and after a 15 mile road test. I did verify pressures before the drive last night, then again this morning. I got on line today and spoke with people at B&M and TCI. B&M wont sell their high rate PR spring without the whole $80+ kit. TCI does sell their purple spring separate and says that it will raise base pressure 15-20psi over the Transgo green spring. That is a step in the right direction at least. I'm also going to go with the .570 boost and .400 low/rev boost valves from TCI. If the trans shifts a little hard, I don't care. It is a Beasty hotrod after all not a luxury sedan.
700R4 Performance Transmission from PATC, 700 Raptor 700R4

Scroll down the page. There are a lot of choices of springs n valves.
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  #42 (permalink)  
Old 11-11-2013, 01:17 PM
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Thanks Texas T for the link.
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  #43 (permalink)  
Old 11-11-2013, 02:12 PM
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I just got off the phone with the guy who built the pump I just put in my 700R4. He sets clearance at .0015" I talked to him about base line pressure. he says that line drop at cruise is an issue on the 700R4. His solution is to shore up the TV spring with extra shims. I told him that I have two of the shims from the Transgo kit in there now with the Sonnax high rate spring and I'm getting about 95psi base line pressure. He said try another shim or two. He agrees that a higher rate PR spring should also help.
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  #44 (permalink)  
Old 11-12-2013, 05:43 PM
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I made up a bushing this morning to shore up the TV spring. I bored a hole in it to allow the Transgo spring shim to fit inside it so that it will increase compression of the spring while still letting the shim do its job. I will also need to be sure that the spring doesn't coil bind at full throttle. I compared coil bind of the Transgo red spring with that of the Sonnax high rate spring. The Sonnax spring hits coil bind about 1/16" before the Transgo spring. The Transgo spring is slightly shorter but may actually be a stiffer spring. I'll experiment with the springs to see which one works best. My goal is to increase pressure on the TV valve at minimum throttle so that base line pressure is increased but still allow the TV plunger to make its full stroke.

Ken from Oregon Torque Converter(the guy who built my front pump) agreed with Dana from Pro Built that the .500 and .296 valves I have are plenty for my application. I get 260psi at full grunt now and may get a hair more with the TCI high rate PR spring. At least I hope the stiffer spring will raise base pressure as that is my main goal in using it. I read yesterday that higher line pressure eats horsepower by increasing parasitic load in the transmission. Maybe some of you more experienced trans guys can comment on this. While I want to be sure I have plenty of pressure to prevent slippage, maybe added pressure beyond that isn't really desirable. I guess I'll go with the TCI spring but forgo the bigger boost valves for now. When I build my new motor in 3 or 4 years and start moving towards 600hp, I may go to the larger valves.
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Old 11-12-2013, 07:45 PM
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Like it when you talk dirty?!. Not many people have any idea what you are talking about except us tranny guys. Like reading about the problems the 700 has because there a lot like the 200 4r problems. My 200 has good pressures, but like yours, mine should have more in fourth, but i'm good to go because I shaved done the piston by 80 thousands and added the third clutch for an additional holding power. When you get it done, let me know how that worked out. I might try something to my spare tranny. I've upgraded it ALOT just for the fun of playing with it.
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