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#1
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200-4R shift question
My 200-4R shifts from 1st to 2nd and 2nd to 3rd at about 5400 rpm at WOT, but it won't try to shift into OD until 6000 rpm. Shouldn't it shift at the same rpm in all gears? Also, when I said it tries to shift into OD at 6000 rpm, that's exactly what I meant. My engine has a hard time getting to 6000, but when it does and tries to shift into OD it shuttles back and forth between 3rd and OD.
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#2
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Is it a stock 2004R? If so, they only have 2 frictions on the over drive clutch and you are likely powering right through them and making them slip. One of the easiest mods to do is add another friction to make 3. The steels are already there, you just need to put the friction in between. But you have to machine .080 from the apply piston for clearance.
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#3
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I doubt it is powering through the two frictions. Pretty generous apply area and fairly large friction area.
I would cut a coil or two off the 3-4 shift valve spring.
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www.jakesperformance.com Racing Automatics and LSx Engine components |
#4
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I thought it was jumping back and forth between 3rd and OD, but maybe it was slipping? My tach was jumping back and forth between 5500 and 6000 rpm. If it was slipping would it catch and let go, catch and let go.....? My engine isn't a super high hp motor, but it is a 428.
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#5
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Jake, I read your 11/08 200-4R rebuild step by step article in the turbo regal website. In that article, you recommended adding a friction clutch to the 4th clutch. Have you since determined that it is not necessary? BTW, it is an excellant article.
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#6
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It's an easy upgrade to do if you have a lathe and method to cut the piston.
The problem is the pistons tend to chatter on a lathe because they are stamped steel. You can't tighten the chuck up enough to keep it from chattering itself off the lathe or you will bend it. I have a fixture I use to cut them that kills some of the chatter and positively holds them. I like to install 3 frictons on the 400+ HP units. However I've never seen overdrive clutches slip on a 200-4R unless there was a pressure issue. It COULD be a clutch slippage issue in your case but I suspect it's not. Take the pan off and look at the OD pack, you can see it exposed somewhat with the pan off, see if they look black. IF they are slipping/grabbing, they will be black.
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www.jakesperformance.com Racing Automatics and LSx Engine components |
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