Reply With QuoteOK, Hammerdown I have a 21' daytona also and was wondering how much you gained for moving the pump back?
Was it worth it?
How does it handle now?
Thanks for the pics Hammer. I need one showing how much to hack off the back.
Prior to "hacking off the back" I sent my Intake to MPD where Jack machined off some of the rear section of the Intake. When NOT fully busting out the back, this allows the Intake to go back a bit more in the Hull vs if the extra material it was not removed.
NOW...it was suggested to me by MPD that unless my 21 Daytona was used more or less as a (race only) boat NOT to fully bust out the back of the transom. Reason being, for a lake/river Hot Rod boat that spends a lot of time in rough chop and just having fun etc there's just a better chance of water leaks and stress cracking if I did do a full set-back. I was advised to leave at least 3/4" of the rear Hull intact, and I did just that.
http://www.***boat.com/image_center/...C00020-med.jpg
Did I move my motor back...?
Yes, since more room in a boat is always a plus, by moving my engine back some +6" I was also able to slide back my rear bench seat.
Below pic shows how I made sure the Intake tilt was perfectly parallel with the bottom of the tunnels, (remember all) measurement must be taken from the under side!
http://www.***boat.com/image_center/...C00030-med.jpg
To set the front rear Intake depth I first located dead center of the keel and ran a string line under the hull. With the shoe in place on the Intake (no shims), the Intake front/back must NOT be lower than the string line/straight egde!
OK, Hammerdown I have a 21' daytona also and was wondering how much you gained for moving the pump back?
Was it worth it?
How does it handle now?
please tell me what the advantages of doing a setback is.
Other tha n more room ,is there a performance value?
Does the setback affect the center of gravity in a positive or negative way?
Some have said I should do a setback,but didn't know what the purpose is.Thanks for any help.
OK, Hammerdown I have a 21' daytona also and was wondering how much you gained for moving the pump back?
Was it worth it?
How does it handle now?
Prior doing the setback my hand hole clean out was in front of the Transom and thus (in) the boat.
For me just a few of the benefits are...(and not in any order)
1) more room in the boat...always a +
2) I can and have removed the clean out with the boat in deep water...= no sinky :squiggle:
3) much easer to remove the bowl...another +
4) with the intake moved back = less wetted surface at WOT = more MPH. Hard to say the exact # because at that time I also put a bigger engine in it with more compression.
Prior to the setback My 12JG had no droop, PD, Ride Plate or shoe. It did have a Berk Jet-O-Vater.
As far a any handling differences, the only thing I notice is now with the long Droop, my steering (off plane) is a little tougher due to the PD in the water.
Oh and since I also moved my engine back it sits about 1/2" deeper in the water.
I also moved my boat 6" foward on the trailer...so it wasn't so ass heavy.
All in all Im quite pleased with the turn out, and would do it again
Yeah I do like the fact that the bowl is on the outside and you dont have to cut apart that transum ring and re-silicon again just to inspect your impeller and bowl
Maybe I will have to go down that road soon in my quest for 100mph :crossx:
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