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BadBehavior 01-31-2013 12:56 PM

Shorty Powerglide in a flatbottom V-drive boat questions
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This is my first post, after lurking for awhile to see if I had a reasonable question(s). I am putting a shorty Powerglide in a flatbottom V-drive boat (RaysonCraft). Last time was 30 some years ago and I need some refresher help. The pics(sorry, Photoshop is not my forte!) show original on the left and a manual valve body on the right, I do not know who the modifier is, wish I did. It was used a rear engined dragster. It was previously used with a Transbrake, the only info he could offer was,"did not have to use brake to backup "? I do not have a use for this in this application.Questions: IGNORE yellow circles.
1. Will "2" be eliminated or transferred to the manual body?
2. Will "4" transfer to "5" with only gasket, could something be missing at "5"?
3. Number "3" came with this unit,can I assume this stays, or not, because,
4. how do I modify this area and have a regular manual valve body??
Thanks to anyone that can advise,

rick 427 01-31-2013 03:29 PM

If you put the transbrake valve body back in,and DON'T put any voltage to the solenoid on the trans,then you will have a full manual shift powerglide minus the trans brake option.What the transbrake does is apply the reverse clutches when in a forward gear. When the button on the shifter is pressed,it activates the solenoid to apply those clutches and keeps the car motionless,since the forward AND reverse clutches are both applied.Release the button,reverse clutches are no longer applied,and the car goes forward[rather quickly at 5500 RPM,I might add] If the button is not pressed,it is just a regular full manual shift trans. But I have no idea,you would know more than me, if shift harshness in a boat application would be a concern.

junior stocker 01-31-2013 03:38 PM

Here's what you do; sell the trans brake valve body to a drag racer, and modify a "stock" valve body into a manual shift unit. All you need to do, is take a 1/4 inch long section of 1/4 inch copper tubing, and use that to block the 1-2 shift valve open(the copper tube would go in FIRST when assembling the 1-2 shift valve). Don't worry about the modulator, or the throttle pressure/kickdown. A Trans-Go shift kit also has a "coil of wire" it uses to block the 1-2 valve open, a drill bit(s) to enlarge the plate passages, and you'd also get the gaskets and springs needed to do the valve body mods. Butch/junior stocker.

rick 427 01-31-2013 04:03 PM

Butch,that is a great idea .......With that said,if you go that route instead,be sure to get a strong pressure regulator spring.I'm not sure a transgo spring would even be enough....TCI has em... In a transbrake built trans,the springs in the reverse piston are extremely stiff,and it requires a lot of pressure to apply them properly. Dont miss that detail.

Crosley 01-31-2013 06:02 PM

In boat applications usually reverse and park are blocked out.

Sell the trans brake v-body as suggested. Buy or build the needed v-body. It is safer and better.

the v-body you have is called a no button back up trans brake. They generally are slower release of the trans brake than a fluid release pro-tree v-body

Main line pressure is controlled via PR spring and the size of the boost valve in the v-body too

DanielC 01-31-2013 07:50 PM

V-drive boats do not have a reverse, unless there is another transmission in there. I agree, no need for "Park". But if you cannot shift into reverse, your only option to move the boat backwards or "to aft" is to row.

rick 427 01-31-2013 09:48 PM

I did not know that type of boat had no reverse....Velvet drives and knowing that ''Park'' consists of an anchor or a few ropes is about it for me on boat knowledge.Thanks for the info.

DanielC 02-01-2013 05:27 AM

Some V-drive boats you cannot shift from neutral to forward without shutting the engine off.
Start it in neutral, warm it up. Paddle around until the boat is pointing the direction you want to go, put it in gear, and start it again. They can be fun to waterski behind.

BadBehavior 02-02-2013 08:24 AM

2 Attachment(s)
Thanks to all of you for taking the time to post. When I saw all these postings, a smile actually came across my face! The detail and the generosity you guys offered ,not found on the web often. You have saved my bacon on this project. I am not new to V-drives.This is my second V-drive of 2012, A 496 that I built last year, and this one is on a tight budget. I hope I do not sound contradictory, but I have always used PGs with reverse and park! 2 tricks here, use reverse at low speed, or risk swamping. The other trick is using PARK, Place in Neutral, rev the engine lightly, the drive shaft will momentarily halt, HIT PARK. Now you can Idle and not have the prop spinning. Also great for tuning. I run a TCI convertor eliminator, and synthetic fluid, and no cooler, and I do not have to shut off the engine to shift, Its a POWERGLIDE! Im hoping to post a pic the project Im working on.
Thanks again, and can I come back??
Larry BadBehavior

ogre 02-02-2013 08:53 AM

''risk swamping'' not a term used often on hotrodders :D
most guys here won't/can't run in the rain or they get swamped...
there are a couple of boat threeads here
welcome to the forum, nice boat

S10xGN 02-02-2013 09:06 AM

This got my curiosity up, what would "park" be without the physical engagement of the pawl? Just another neutral?


rick 427 02-02-2013 02:07 PM

Larry,your technique is very interesting.That is a great looking boat......S10xGN,the park pawl is still used,its not eliminated.As he said,he slightly hits the throttle in neutral to momentarily stop the driveshaft from turning,then puts it in park.If just left in neutral,the prop would still spin.

BadBehavior 02-02-2013 05:08 PM

Rick427, I discovered this technic 30 years ago. I had just put my first powerglide in and curious to see if it would even work. Well it seemed to be doing ok so feathered the idle and the drive shaft stopped, OH $xxx, I thought broke something in the tranny and shoved it into Park. Didn't hear any strange noises, so back into gear, tapped the throttle, stop driveshaft. Been doing that since.

AutoGear 02-04-2013 08:52 AM

Very cool! My first (non family) job was for a local boatyard that restored old boats; mostly wooden, but they would take on just about anything if you were willing to deal with long turnaround times. We used to have a guy that trailered his offshore racing powerboat (3 blown 502"s I think) in at 5am; put it in the water; blast to the other end of the lake, drink coffee and eat french toast and come back. Then he'd hang around all day and get in the way; but the gas bill and my tip made it worthwhile

Get some video of that classic flatbottom doin' work please?

BadBehavior 02-04-2013 01:14 PM

Flatbottom video
AG, I lost a good deal of video to a crash, I'll see if i can find a thumbdrive that may have some vids, when i get back home i'll have to check.

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