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Forrest
08-30-2004, 09:56 AM
Light at the end of the tunnel . . .

Forrest
08-30-2004, 10:09 AM
. . . the old 280Ts are out and the holes are re-cut for the DPXs . . .

Forrest
08-30-2004, 10:16 AM
All the rain we got in North Florida this summer really made this job difficult to say the least . . .

Greg K
08-30-2004, 11:09 AM
Forrest,
Those look great and are a great addition to your Magnum. I bet they'll perform great too.
Did the helms have to be changed out for the steering?
:beer:

Forrest
08-30-2004, 11:18 AM
Thanks Greg.

Oh yea, it's now a power-assist full hydraulic steering with four rams. I had to pull the Big-T cable head and install a Char-Lynn 160cc hydraulic helm.

Lenny
08-30-2004, 11:26 AM
WOW :eek: Looks great !!! Whne do you run her? The profile on the DPX sure shares some lines of the Blackhawk.

Eugene Nahemow
08-30-2004, 12:19 PM
Forrest,
Those drives look incredible on the boat.
I really can't wait to hear how they perform.
Regards.

Forrest
08-30-2004, 04:47 PM
Lenny, when do I run her? :boggled: It seems like never with all the work I been doing lately, either on one of the houses or on the Magnum. I do plan on running her this weekend at Eufaula 6 though. I'll need to figure the prop thing out. I have an E3 and an E4 set to try. I think with the 383s, the E4 set will be too much pitch. I'm running 1.59:1 gears. Unlike the Blackhawk, the DPX is not to be configured as surfacing props; however, when mounted on the same crankshaft centerline as the old Volvo 280s, as they are, the X-dimention of the DPX drives are almost 2 inches higher than the 280s.

Eugene, thanks! I can't wait to try 'em out either! I'll let you guys know what happens.

smoothie
08-30-2004, 05:28 PM
Forrest,your Magnum sure makes those outdrives look great!

Cuda
08-30-2004, 05:34 PM
Those drives look beefy! How much power are they rated to handle? You just answered one question I was about to ask, whether you had to raise or lower the engines. I assume you didn't have to move them forward or back either.

You got a shot of the interior? I'm trying to talk Debbie into letting me put a candy cane interior in the boat.

Forrest
08-31-2004, 09:49 AM
Cuda, the engines stayed essentially in the same place as they did when thaey were hitched up to the 280 drives. The DPX drives use the same type of mounting system as the 280 and all older Volvo drives where the bell housing tail-piece is rubber doughnuted through the transom unit. The length of the new DPX bell housing is the exact same as the old 280 bell housing. I did go ahead and replace the old and rusty factory one-piece offshore mounts to Hardin one-piece offshore mounts (http://www.cpperformance.com/detail.aspx?ID=845). Because of that change, I was forced to painstakingly re-align the engines to the drives using a laser, a long straight-edge, and tape measure. Once it did that, I realized that the engines were originally mounted misaligned with the old 280 drives. Unlike Mercruiser, Volvo SX, OMC, and other drives that use a gimble bearing, slight engine to drive misalignment does not cause premature wear of the coupler in the "Aquamatic" mounting system. But in any event, the engines are dead-on aligned with the new DPX drives - which caused other problems. Now after the engine realignment, there wasn't enough room between the engines to install my nice set of Stainless Marine manifolds. Those band clamps that attach the risers to the manifolds needed another 1/4"-inch clearance to install the manifolds. :eek: In this case, a quarter of and inch may as well have been a mile! Well anyway (don't tell Brownie), I took the manifolds apart from the risers and broke out my 4" rotary angle grinder and installed a new 24 grit sanding disk and proceeded to grind off a flat of 3/16" from the outside edge of the riser mounting-flange from both manifolds and stainless-steel risers. After that, I modified the riser attachment clamp by carefully cutting a section of the hard ring away from the inside of the band clamp on the side corresponding to the flats that ground on the mounting flange. Guess what? It now fits with about 1/16" (or less) clearance between the manifolds, and does not leak exhaust. I know, it took some deep soul searching (have I lost my mind!) before I took a grinder to a perfect pair of Stainless Marine exhaust manifolds. Pictures and more insanity to follow.

Here are the candy stripes! (http://www.donzi.net/forums/showthread.php?t=35527)

seano
09-01-2004, 03:19 PM
hey forres, the boat look incredible as usual....can't wait to hear the numbers...!

what are you doing with the old drives and transom assemblies? are they any good?

Forrest
09-01-2004, 03:45 PM
Thanks Seano! I can't wait to try her out as well. The thatk-out 280T drives and transoms were both sold eariler this summer.

Bigbroadjumper
09-02-2004, 04:36 PM
Wow your boat looks great! I am so upset that we had to cancel. I want to drive to Eufaula just to see your boat. Can't wait to her how she runs with all the changes. I took mine to Lake Geneva WI today for a few hours. I ran one Hill stainless and the other a NIBRIL. When she is out of the water it looks like I have one black and one sock on. LOL But since I did the head work I am turning about 4800 RPMS and 58 MPH on the GPS.

Good luck with the weather and have a great time. I will see you at the next event...come hell or high water.

Forrest
09-08-2004, 02:15 PM
The one time out in Eufaula on Saturday I quickly found out that the E3 props would only let the engines turn 4000 RPM; however, though I had forgotten to bring the GPS :bonk: , seat of the pants told me that this old Magnum has never gone faster even though I could not get the RPM up into the power band. Handling is improved 200% with the twin duo-props, integrated external power hydraulic steering, and updated lower unit design over the 280T drives. Except for the props, I'm totally satisfied with the upgrade.

Now I'm looking for a set of E2 props. My E3 and E4 sets are now for sale or trade.