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  #46 (permalink)  
Old 11-13-2013, 03:28 PM
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Thank you dwwl for reassuring me that I'm not the only one out here playing with these things. I know that we're supposed to either have a pro do the trans, or follow the instructions in the shift kit, and just live with the results. I have great respect for Dana at Probuilt Automatics who got me this far, and I highly recommend his services, but I still feel like I want more pressure at less throttle and Dana thinks I'm OCD. Of course he's right about me being OCD but I still want more pressure at less throttle. It was cool to speak with Ken at Oregon Torque Converter. He's a 35 year Trans building veteran and he has a great depth of knowledge on these units and their issues. Like Crosley who turned me onto blocking the line bias valve for higher max pressure at full throttle. Ken was right on track with me trying to boost base line pressure.

I know that part of maintaining good pressure at low pump volume is curing internal leaks. I'm sure that my valve body at 30K miles of performance driving and lots of manual shifting probably bleeds pressure around the manual valve at least. At some point I will probably talk to Ken about one of the valve bodies that he also builds for OTC. For now though, the trans is so close to perfect I really think I can get it there with just minor tweaks. I'll post what I come up with after I get done with it, as well as any further brain storming ideas I come up with along the way.

For now, I'm going to install the TCI high rate PR spring. At $16 with shipping, it's a cheap thing to try. I'll play with the TV valve train and the bushing I made up to see how that works. I'm going to pinpoint the issue with my TCC controls to get that working the way I want, and I'm going to address the soft 1-2 shift at light throttle that started with the new shift kit install. I'm thinking I left the 2nd accumulator piston seal out of the new accumulator. Dana says the shift is meant to be mild at light throttle and get progressively firmer with throttle. That's pretty much what I've got now but I liked the shift I had before-firm but not harsh at light throttle and neck snapping at hard throttle-and want to get it back. I left everything affecting the 2nd gear shift the way it was while doing the rest of the Transgo shift kit. All I did was install the new accumulator. I still have the old one which is in fine shape. Think I'll just swap it back in.

I guess as long as I don't wear the threads off of the fasteners in the transmission pulling it apart and putting it back together, I'm okay.

P.S. I need to close the book on this transmission at some point and start saving in earnest for my new engine project. That should certainly put my OCD in high gear.

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  #47 (permalink)  
Old 11-14-2013, 07:39 AM
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Dana put together my kit after I told him what I wanted. Everything was in the kit for a total rebuild. I've have about 2000 miles on my 700, then I decided to paint my Camaro, that was a year ago. In the last year I've only driven it about 10 miles, up & down the drive way an a few runs down the street, no fenders, hood, glass. The last thing I did to it before paint was I found a governor in a 700 that someone elas had torn apart at the pick n pull, don't know what the 700 was in before but the weights on it were a lot thinner than mine were. All I did to it was clean it up an put it in, it made a big difference shift points were higher. Here's a question my torque converter is 2800 stall when I'm in 4th an TCC is locked up, going 70 mph my rpms are at 1900 to 2000 how much slipage is going on in the torque converter or is there any at all since its locked up. Maybe I answered my question, since its locked up there is no slipage. Am I right on that?
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  #48 (permalink)  
Old 11-14-2013, 11:26 AM
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You are right that with the converter locked there should be no slippage in the converter. There would have to be low pressure at the converter clutch circuit or a damaged converter clutch for it to slip. With Dana's kit(dual feel check valve and increased line pressure), you should feel the TCC engage, not like a hard shift but you should feel it lock, and see the revs drop a little. One clue to the converter clutch being engaged is drivetrain harmonics transferred through the chassis. It's hard to describe but you feel it in the floorpan and seat, even on a stock vehicle without PWM TCC. If you pay attention as the TCC engages, you'll see what I mean. It feels like the rear wheels are solidly connected to the crankshaft, which in effect, they are.

I love the trans with Dana's upgrades. With the Transgo shift kit mods he had me do, I can shift between 2nd and 3rd at any speed and with the boost valves I am running, the FT 1-2 shift hits at 6,300 anyway so I have no shift point issues. I am only trying to raise base line pressure from the normal 90psi to maybe 110 or so. This is strictly to increase clutch apply pressure at cruise(1,500rpm). I don't spend much time at that low rev but on a summer day if I decide to go on a leasurely highway cruise with the TCC locked up, I want to be sure that my 3-4 clutches are tightly applied. This is probably completely unnecessary as I'm sure that 90psi, especially with the brutus 3-4 clutch set up Dana helped me put together, there is plenty of force on the clutches. Last summer though, with the build being much less ideal, I did smoke a really tall 3-4 clutch stack in the very same driving conditions. That's why I'm being so OCD about it this time.

Dana and ProBuilt is the first place I will ever go for trans parts and upgrades. I will continue to recommend him to anyone looking for help with a transmission. I am very pleased with the results of Dana's kit and enjoyed working with him on this. The fine tuning I'm doing on it is just because I think I can perhaps make the trans a little more to my liking. If this doesn't work out, lesson learned. It's all just me learning more and more about these units as I go.
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  #49 (permalink)  
Old 11-14-2013, 11:59 AM
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I said I would post any new brainstorm ideas I had through this process. This morning I was looking through the growing collection of valves, springs and other goodies I have the for the 700R4. I keep bagging them up and then I keep pouring the bags back out on my table looking for things(OCD is so much fun). I found an extra Transgo no stick TV set, including an extra spacer I didn't know I had. With the spacer on hand, I was able to test my shim and spring setup for coil bind before the spacer engages the plunger and valve. This would be the max compression of the spring in operation. The test confirmed that the spacer engages about 1/8" before coil bind of the spring with the spacer. So, it looks like my shim will work.

The test got me thinking that a tubular spacer may be better than the thin metal Transgo piece. Dana provides two spacers in his kit to ensure the spacer doesn't buckle. I was thinking that a tubular spacer might not only be stronger, but it will also help support the TV spring as it's so close to coil bind. I found a piece of old 5/16" tube and precision sized a piece to the exact length of the spacer. The tube fits my shim and the spring very well and will replace the spacers very nicely.
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  #50 (permalink)  
Old 11-14-2013, 01:28 PM
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You have to think outside the box to really understand these trannys. Some the articles I've read are not 100 per cent correct. I have tore down four 200 4r trannys and everyone had six clutches in the direct clutch assemble. Some of the articles say that they all had five. All mine came from behind V-8 and not six cylinders. I didn't dual feed my 200 because i'm not racing it and i'm only about 300+ pones. For less vibration, I cut a stripe of old inter tube and folded it over and put it between my cross member and the frame on both sides. I know the tranny mounts rubber is suppose to take all the vibrations, but I used that trick from a old mechanic/body man years ago and its worked well for me. I'll see how your trick works on mine in a few days when I got time to see how it function on by spare tranny.
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  #51 (permalink)  
Old 11-15-2013, 08:14 AM
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Thinking outside the box, well here's one idea, drilling 3 or 4 1/16 holes right above the clutches on the reverse input drum. To expel ATF from inside of it. I can't remember the formula for ozs. of oil spining at high rpms that quickly turns into pounds.
Another little trick I read about was to use .060 cut washers between the torque converter an flex plate. Suppose to help keep the torque converter ingauged with the pump.
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Old 11-15-2013, 11:37 AM
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I'm not sure on a 700R4, what benefit there would be to drilling relief holes in the reverse input drum, aside perhaps from improved lube to the band. However, I did drill a ring of small holes around the top of the input housing. I run the Sonnax Smart Tech housing(read as big bucks) and it uses a bolt on backing plate with no place for oil to bleed off behind the 3-4 clutches. The factory housing uses a snap ring and drop in backing plate where oil can bleed out the back of the housing. I was concerned that the oil being trapped in that spot might hinder cooling. After the later meltdown of my 3-4 clutches, I drilled the holes which allow cooling oil to move more easily through the 3-4 clutches. These small holes will have no affect at all on the housing's brutus strength. Anything to prevent future failure of that clutch pack is good.

My tube spacer is out, replaced with a piece of 5/16" round stock. Playing with the setup to recheck coil compression and look for any issues(read as OCD), I noticed that the blunt end of the tube could catch on the spring coils and prevent normal action of the assembly. The blunt end could also get caught on the shim I made if it falls out of the bore, which is likely during operation. Creating chamfers on each end of the spacer, along with chamfering the leading edge of the bore in my shim, solves the problem by allowing the spacer to slip past the spring coils and into the bore. However, chamfering the tube creates a thin line of tube to act on the plunger and TV valve. I worried about durability and even with the small bit of chamfer the tube would allow, there is still a chance of it catching.

The solid round stock allowed me to create more severe chamfers, cutting each end down to 1/4" and tapering back to create a ramp that will prevent any catching on the spring coils or the bore of the shim. I did also chamfer the inner edge of shim bore. In checking the set up, the spacer slides cleanly through the spring and shim. Now I have an assembly that should work smoothly.

On a different note, I'm again pleased with Summit Racing. For a larger company that could be slow in their shipping, they have done very well for me now on my last 3 or 4 orders. This time, I ordered the TCI PR spring Wednesday about 11:30am. I figured I would wait til next weekend to do the work and ordered the part using the cheapest method of shipping. According to Fed Ex tracking, the part is in town and scheduled to arrive at my door today at 4:30pm. For cheap ground freight, that is quick service.
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Old 11-15-2013, 04:20 PM
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Just figured out a shade tree method for bench testing a TCC solenoid. This would only be good on a non PWM solenoid. I used a blow gun, a 12v jump starter, and two test leads. I put one mounting ear of the solenoid in a vise to hold it securely. Then I connected the test leads to the jump box and connected the negative test lead to the black lead of the solenoid. While applying air to the solenoid with the blow gun, I touched the positive test lead to the red solenoid lead and heard the solenoid click and the blow gun pushed away from the solenoid, indicating the solenoid was working and stopping flow. This solenoid only clicked once when I tested it without air. It clicked to close, but without pressure, it didn't open and therefore didn't click again. With pressure applied, it clicked shut every time it was activated.

Now I know how to test the TCC solenoid when I get to that point in troubleshooting my TCC system.
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Old 11-15-2013, 06:58 PM
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good thing I have a good memory, these are things I can try on my spare tranny. I'm going to have some spare time this winter, so i'm going to pull my spare 200 4r down and go threw it again and kind of implement some of these ideas.
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Old 11-16-2013, 01:17 PM
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Today is the day. So far, I've pinpointed the no TCC lockup issue to the ECM controlled relay not activating. It activates when voltage is applied to the TCC signal input of the ECM. Trouble is, it seems to activate whenever there is power to that input, regardless of throttle position, engine speed, or engine load. This tells me that, even though my UTILITIES function in CALMAP shows these as adjustable TCC factors, the ECM doesn't have this function. I'll play with it some more and see if there isn't something I'm missing. Otherwise, I'm going to have to do this the old school way using the brake switch and a vacuum switch if I want full TCC control.

Good news is, when power is applied to pin A of the trans, the TCC solenoid does activate. Concerning the soft 2nd shift that started with the shift kit install, I pulled the 2nd accumulator the came new in the kit and no piston seal. This was my first thought and shame on me for not checking and just installing it as it came out of the bag. So far, my TV valvetrain has gone together great with the new spacer and shim and the high rate spring is installed at the pressure regulator. I measured the actual thickness of the spring wire and it is about .004 thicker. It also has greater coil density than the Sonnax spring. It's hard to tell squeezing a spring between your fingers whether it's stiffer than another, but it seems to be. We know soon how this all affects pressure.
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Old 11-16-2013, 03:24 PM
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Base line pressure is now 135psi cold. I expect it to drop 10 or 15 lbs warm. That will put it right at 120psi. Much better than 90psi I think. I will check fluid temp after the short drive back home. I'm not sure what the affect of high MTV pressure might be on fluid cooler flow. I'm also going to experiment using my power probe to apply power to the TCC enable signal of the ECM. I want to be sure that this activates the converter clutch as expected. The TCC control function of this ECM is looking alot like the factory 87 GM's controls.
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Old 11-16-2013, 05:46 PM
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Guess what I learned in school today? Raised MTV pressure raises shift points. My shift points were already higher than stock. With the .195" shim installed, the trans would shift from 1st to second at about 30mph minimum. A little too high. I'm starting to see why guys like Crosley and Dana at Pro Built don't include "add a .195 shim to the TV spring" to there recommendations for a great shifting 700R4. I'm in the process of shaving the shim down to .100". This should still give some rise in base line pressure and bring the shift points back into reality. I was about to just dump the whole idea and put things back the way they were but naaaah.
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Old 11-18-2013, 09:44 AM
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Getting closer to where I want to be. The shifts are awesome now. 1-2 shift is still a little bit high at full throttle. It has auto shifted 1-2 at 6,300 for as long as I can remember, which is just about perfect for this car. I'm going to cut my shim down to .060 and see how that does. The rest of the shifts are perfect. With the Transgo 2-3 shift kit mods from Pro Built, I can shift between 2 and 3 whenever and at whatever speed I want, so that's not a problem. With the accumulator piston seal installed in the 2nd accumulator, the 2nd shift is now just right. I'll play with the TV spring shim next weekend and when I get the 1-2 shift where I want it, I'll take another base pressure reading.

On the TCC control issue. My testing yesterday with the Power Probe indicate that the NC pressure switch I installed in the 2nd clutch circuit is open in 2nd, 3rd, and 4th. With the Transgo shift kit installed, I thought that there wouldn't be pressure on the 2nd circuit in 3rd, apparently I was wrong. The switch may also be no good but since these switches aren't available new, I'll most likely delete it. I may just end up following the TCC control design from Tony's 700R4 pages. This gives the option of lock up in 4th, or 2,3 and 4, or no lock up at all.

One thing I'm noticing is that the hesitation of the 1st 1-2 shift after cold start is back. I'm thinking this might be due to having the 4th accumulator piston back in. I had replaced it with a piston I had drilled. The Pro Built mods have you delete the 4th accum piston and spring but with the huge spring I have in the 2nd accum, I wanted the 4th accum spring in there to back up the separator plate. I may have to pull the VB again and swap the 4th accum piston back to the drilled one.

I'm, being reminded of the wise words of an old timer who told me way back "When modifying any system, make only one small change at a time. This way you can note the effect of each change and keep track of what change has what effect." I have a hard time following this rule, especially when it comes to this transmission. I have all these brainstorming ideas and I just want to do them all. Now I am going to have to backtrack and possibly spend even more time to get where I want to be. Live and learn.
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Old 11-18-2013, 11:30 AM
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Yea, I know what your saying. I also have to go back into mine and put the spring back on the large governor weight. It shifts just right on every gear but it shift back to third from fourth to quickly when I push on the gas. I took some weight off the governor and got it right, but though i'd get it better by removing the spring like I read in some article. Its easy, just dropping the pan and its right there. I'm going to wait till spring now and play with the other tranny again that I have for a spare.
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Old 11-18-2013, 01:55 PM
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Can you use the TV bushing mod like we can on the 700R4? It deletes the part throttle 3-4 downshift so you only get 3-4 downshift at full throttle.

My only shifting issue is from 1st to 2nd. I actually don't mind the light throttle 1-2 shift with the .100 shim. The engine winds up a little and the shift is tight but not harsh. It's almost like shifting a manual trans. It's just the full throttle shift that's the problem. The engine revs to about 6,700, past the engine's power band which ends at 6,300, then holds for about .2 seconds before it shifts. This would suck at the dragstrip. The car actually loses alot of momentum in the pause between shifts. Later, when I'm running my new motor that will make power to 6,800, that shift point might be perfect.

I could just try changing the 1-2 shift valve spring, but that's a whole other can of worms. Think I'll just work backward on the TV spring shim until the shift is right and then see where my base pressure is. If I can get 110 or 120, that would be great.

I'm grieving right now over the realization that I probably won't have the TCC controls that I was hoping for. The ULITILIES page of my CALMAP software has a list of TCC control items like MIN TPS, MIN RPM, TBD(torque before disengage I think?). It makes me think that the ECM will shut down the TCC relay according to these factors. In my testing, I came to realize that the ECM powers up the relay when you apply 12v to the TCC enable input. The fact that this input goes to the trans harness is obviously an oversight. The harness must have been intended for other systems that used different control strategy.

It's looking like I'l just need to connect 12v from the brake switch to the TCC enable input and then rely on the pressure switch in the trans to activate the solenoid. This will mean that I'll have lockup constantly in 4th. I guess I can live with that, it's just disappointing.
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