Turbo-Hydro 350 operation - Page 2

bill dedman · 06-26-2007, 06:06 PM

Glenn, I called that number but was too late. I'll call again, tomorrow (Wed.)

Thanks!

Billl, in Conway, Arkansas

bill dedman · 06-27-2007, 12:34 PM

Turns out that the vacuum modulator for the 350 and 400 turbohydros are readily interchangable, so the TECKPAK cable-operated mechanical replacement for the vacuum OEM unit that they advertise for the 400 will also work just fine on the 350. End of problem.

Took a lot of digging and a lot of "help from my friends" (and, you know who you are) to find this out and verify it.

All this could have been avoided if the ^%$%##!!!! ('scuse the French!) information on the TECKPAK website had included the 350... but, that's the way it goes, sometimes.

Seriously, thanks to all who helped me sort this thing out; you ~all~ helped a LOT!!! Your information and advice was VERY much appreciated!

You guys are the best...

Bill, in Conway, AR

Bad503 · 06-27-2007, 02:11 PM

A TH350 with the modulator unhooked will upshift, there are a few issues with doing this,
1 the trans will shift very late and very hard.
2 the trans will be a full line rise all of the time this causes the unit to put alot of stress on the sealing rings on the rear of the pump. If you drive it on the street, the rings will fail, and probably ruin the pump and the direct drum.

Think about this, If this was a drag race application you might shift it manually; you will most likely be at full throttle all of the time. At full throttle your engine
will have little or no vacuum in the manifold, so what is the difference.

bill dedman · 06-27-2007, 04:51 PM

>>> "so, what is the difference?" <<<

Seems to me the difference is that

1. at low rpm, you can force a 1-2 shift, or a 2-3 shift at any rpm, if you have a full manual valve body, which if you read all the notes in this thread, you'd be aware that that was the plan, and

2. at low rpm's, the transmission's pump isn't making the kind of main line pressure that wll create bone-jarring shifts, especially, with a fairly loose converter.

But, it's moot anyway, since we found out that the 400 mechanical modulator adapter will also work on the 350. We'll go that way...

Thanks much for your input!

Bill, in Conway, Arkansas.

06-26-2007, 06:06 PM	#11
bill dedman VIP Member Join Date: Feb 2002 Location: Conway, AR Posts: 1,739 Likes: 0 Liked 6 Times in 4 Posts	Glenn, I called that number but was too late. I'll call again, tomorrow (Wed.) Thanks! Billl, in Conway, Arkansas __________________ Bill

06-27-2007, 12:34 PM	#12
bill dedman VIP Member Join Date: Feb 2002 Location: Conway, AR Posts: 1,739 Likes: 0 Liked 6 Times in 4 Posts	Turns out that the vacuum modulator for the 350 and 400 turbohydros are readily interchangable, so the TECKPAK cable-operated mechanical replacement for the vacuum OEM unit that they advertise for the 400 will also work just fine on the 350. End of problem. Took a lot of digging and a lot of "help from my friends" (and, you know who you are) to find this out and verify it. All this could have been avoided if the ^%$%##!!!! ('scuse the French!) information on the TECKPAK website had included the 350... but, that's the way it goes, sometimes. Seriously, thanks to all who helped me sort this thing out; you ~all~ helped a LOT!!! Your information and advice was VERY much appreciated! You guys are the best... Bill, in Conway, AR __________________ Bill

06-27-2007, 04:51 PM	#14
bill dedman VIP Member Join Date: Feb 2002 Location: Conway, AR Posts: 1,739 Likes: 0 Liked 6 Times in 4 Posts	>>> "so, what is the difference?" <<< Seems to me the difference is that 1. at low rpm, you can force a 1-2 shift, or a 2-3 shift at any rpm, if you have a full manual valve body, which if you read all the notes in this thread, you'd be aware that that was the plan, and 2. at low rpm's, the transmission's pump isn't making the kind of main line pressure that wll create bone-jarring shifts, especially, with a fairly loose converter. But, it's moot anyway, since we found out that the 400 mechanical modulator adapter will also work on the 350. We'll go that way... Thanks much for your input! Bill, in Conway, Arkansas. __________________ Bill

06-27-2007, 02:11 PM	#13
Bad503 Junior Member Join Date: Mar 2007 Location: Hays KS Posts: 28 Likes: 0 Liked 0 Times in 0 Posts	A TH350 with the modulator unhooked will upshift, there are a few issues with doing this, 1 the trans will shift very late and very hard. 2 the trans will be a full line rise all of the time this causes the unit to put alot of stress on the sealing rings on the rear of the pump. If you drive it on the street, the rings will fail, and probably ruin the pump and the direct drum. Think about this, If this was a drag race application you might shift it manually; you will most likely be at full throttle all of the time. At full throttle your engine will have little or no vacuum in the manifold, so what is the difference.