Can Somebody Help Me Understand Valve Bodies?

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Can Somebody Help Me Understand Valve Bodies?

Postby Begle1 » Fri Feb 23, 2007 6:06 pm

I recently started thinking of buying a manual valve body for my truck two years ago. :roll:


Can't quite figure them out though.

Some are forwards and some are backwards... I guess some of the forwards have Reverse lock-out? Or is that something installed on the column?
Some come with transbrakes, some don't. But some have provisions for a transbrake in case you want to install one later? If I could, I wouldn't mind keeping the option open.
Some have engine braking, some have no engine braking in 1st, some have no engine braking at all. What's the differences in each of the designs? The ones with engine braking seem just as cheap as the ones without, so I'd assume theres a trade-off...
They also have automatic-manual valve bodies that shift automatically if you put them in drive but shift "full manual" for 1st and 2nd. Do these things have any advantage over a typical automatic valve body?

I think I'd prefer something with a forward shift pattern and, if possible, transbrake provisions and reverse lock-out. And if there isn't a downside, I wouldn't mind to retain engine braking, but I don't think it'd be worth it if you have to sacrifice some of the strength of the valve body.


And then, if I do get the valve body, would there be any other tranny modifications required to fully take advantage of it?

I'm also planning on getting a torque converter at the same time; would there be a difference in optimal converter design if I'm running a manual?

Thanks for any help. :D
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Postby wannadiesel » Fri Feb 23, 2007 6:22 pm

The point of a reverse pattern valve body is to prevent people from shifting from 3rd to reverse. Not that we know anyone who would do that... :twisted:
'93 D350 LE Club Cab dually, Getrag, 3.54 Pow-R-Lok with: DPS EDM's, HTT Stage IV/14wg, Con-FE, Snow Stage 2 water/meth, custom fuel pin, Walbro secondary fuel system.

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Postby Begle1 » Fri Feb 23, 2007 6:45 pm

wannadiesel wrote:The point of a reverse pattern valve body is to prevent people from shifting from 3rd to reverse. Not that we know anyone who would do that... :twisted:


I stand by my previous statement; that transmission moved its shift points all by itself... :oops:
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Postby KTA » Sat Feb 24, 2007 6:14 am

Unless you have a 727 I dont think you can get a reverse manual valve body. I have a full manual on the 47re on the pull truck and I like it. You pick what gear it is in and when, its unconditional. Want to start in 3rd it will no problem. :D
Fleet of Junk: 1989 D350 627rwhp 1300 tq B-1/Hx60 twins, KTA pump/injectors, ported head, BIG fuel supply. 13.75@ 109.5mph 1/4: 1992 W350 Cab-chasis, 1993 W350 ext cab cust.370 inj Hx40/16cm 290rwhp hydroboost brakes,1984 D350 crew-cab another project.
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Postby TOMTOM » Sat Feb 24, 2007 9:07 pm

Who makes the full man v/b for the 47re?
TOMMY
93 CLUB CAB LE SHORT BED 209,000 MILES AUTO/OD 3.54 GEARS 4" TURBO BACK EX NO MUFFLER P7100 PUMP MODS B/D INJECTORS 13.55@99 MPH 440HP 967TQ ON #2 ONLY. PSD INTERCOOLER,BD SUPER B TURBO)47RE FULL MAN SUNCOAST TRIPLE DISC
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Postby Begle1 » Sat Feb 24, 2007 9:33 pm

I have the good ole' 727 in my truck; one of the major things I like about it. :D

I don't know if anybody makes a full manual for the 47RE... Would a valve body from a 727 work on a 518/ 46RE or 618/ 47RE? I would assume that the extra gear/ lock-up torque converter requires a more advanced valve body, but maybe you could jury-rig manual overdrive and lock-up controls while only using the valve body for 1-3? (That's probably far fetched.)

Summit doesn't have anything listed as a manual valve body for the 47RE. They have a few automatic valve bodies, but no manual ones; maybe Suncoast, ATS, Goerend or DTT could hook you up, or even make you a custom one if you really want.


I figure that my truck stays light enough that I could get away with running in 3rd gear most of the time and save my clutches, driveshafts, differential and u-joints from the shift brutality. :twisted:

But the original questions still stand: Would I want a loose converter to absorb some of the shock, or tighter-the-better? Do I need to make other tranny modifications to take full advantage of the manual? What are the advantages and disadvantages of the manual-automatic models or the engine braking models? Is there a downside from buying a model with transbrake provisions and maybe installing the transbrake a few years down the road?
1990 D-250 Regular Cab: Tweaked injection pump, built transmission, a cataclysmic charlie foxtrot of electronics, the most intense street-ran water injection system in the country, and some more unique stuff.
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Postby wannadiesel » Sat Feb 24, 2007 11:26 pm

You need a converter that's matched to your engine. The more torque you make, the tighter it can be.

If you'd get off your butt and tweak the pump a little bit you could make enough power to run 3rd all the time - but be warned that the slippage in the converter = heat, so you need a trans cooler that can handle it.

Trans brakes are rough on the driveline, harder than a brake stand because of the shock when you release the trans brake. I would not do a trans brake.
'93 D350 LE Club Cab dually, Getrag, 3.54 Pow-R-Lok with: DPS EDM's, HTT Stage IV/14wg, Con-FE, Snow Stage 2 water/meth, custom fuel pin, Walbro secondary fuel system.

Best dyno: 408/844
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Postby Begle1 » Sat Feb 24, 2007 11:42 pm

But I can't tweak the fuel screw until I have the transmission that can take the added torque... :P I figure the tranny/ fuel screws will all be the same day, that way when something explodes I'm totally clueless as to what caused it. :lol:


I assume that a brake stand is a slightly more gradual release than the transbrake? The transbrake is a few hundredths of a second quicker but is also a larger shock? Regardless, for $10 I would consider keeping the option open as long as I'm not sacrificing anything.
1990 D-250 Regular Cab: Tweaked injection pump, built transmission, a cataclysmic charlie foxtrot of electronics, the most intense street-ran water injection system in the country, and some more unique stuff.
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Postby wannadiesel » Sun Feb 25, 2007 8:38 am

A brake stand loads the driveline and suspension gradually. With a trans brake, the truck will sit there like it's in park until the brake releases, then full torque will hit the driveline. As far as the driveline is concerned, it's harder then flooring the truck in neutral and dropping it into drive. Good way to spit out u-joints, shear teeth off gears, and snap axles.

On a lightweight drag car with the driveline and suspension to handle it, it makes for an awesome launch. On a heavy pickup you'll probably just get some brutal wheel hop and broken parts.
'93 D350 LE Club Cab dually, Getrag, 3.54 Pow-R-Lok with: DPS EDM's, HTT Stage IV/14wg, Con-FE, Snow Stage 2 water/meth, custom fuel pin, Walbro secondary fuel system.

Best dyno: 408/844
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