25 Daytona Twinstep 2" Shorty

Bo · 04-22-2002, 12:23 AM

Just took my 25' Daytona out for a couple of first high speed runs with new Keith Eickert 800hp blown 540 and wanted to share the experience. I have a 1999 twinstep with 540ci 871 Blower shop blower and twin 750s. Running 7lbs boost and 29 degrees timing. Motor was dynoed at 789 trq @ 4400 and 780hp @ 5500. Running stock Bravo 1 HP 1.36 and 30 pitch Lab finished Bravo 1 drive. We pulled two runs at approx 105 and 108mph on our speedo at 5500-5700rpm's. Unfortunetly we didnt have the GPS with us, although we've seen usually 2-3 mph difference between the Gaffrig and the GPS. This was my first time over 100 in this boat and it was wild! Face is Strecthed and things seem to be happening much faster than they were at 85. Hopefully we'll get a chance to get some GPS runs in this week or next and post them. Main reason for posting this info is because I have a 2" shorty IMCO ordered and wanted to post the changes in speeds and handling. Until then, Cya's !!

Bo · 05-04-2002, 08:31 PM

Went out today for couple of hours with 50 Gallons fuel, 3 passengers (200, 215, 185lbs) slight chop, 60 degrees. Pulled two runs. First run was 105.1 mph at approx 5300rpm and second run was 106.0 at approx 5400rpm. Had problem with hatch lifting up at high speeds.

7lbs boost/1.36 Bravo HP drive/30 Lab Bravo 1

We should have our two inch Imco Shorty by Monday and hopefully weather permitting we can get out and test.

Bo · 05-12-2002, 12:38 AM

Finally got the 2" shorty IMCO (satin finish) lower unit bolted on to the boat today. Lower unit came with 1 1/4" prop shaft so we had to replace the prop hub with new adapter. No place for the drive shower pickup on a shorty and no speedometer pickup/inlet. This thing raised the height of the prop so much we had serious doubts about it working at all. Heres what we ended up with. Two people on board, 50 gallons fuel, 30 labbed Bravo 1, 1.36 gears, 790hp at 5500(Keith Eickert motor), just a slight ripple on the water (No chop). Planing was accomplished first try but it is definitely at the brink of being unacceptable. Failed 1 plane attempt out of approx 6 tries. Seems to get through initial part of planing..but as the nose drops it starts to cavitate and could go either way. Once on plane we did some turns at 40-50-60 and it seemed safe and didnt cavitate as long as we didnt let off. Surprisingly, the boat still seemed to respond very similar to the trim as it did with the Bravo 1. Felt the best at the number 2 on the bluewater trim gauge, as usual. We finally got the nerve to go WOT not knowing if it would blow out or fly off orsomething strange

The first WOT run took us to 110.0 exactly on Garmin GPS. The 2nd took us to 108 but we were running out of room. So it looks like we definitely made at 4mph gain over stock config. 112 is probably within reach in good conditions. the water was almost flat compared to our initial stock test. Going to try a 1" spacer, jetting down 2 sizes, possibly goto 8lbs boost. Anyone have any luck with Hydromotive Props versus Bravo 1 on these hulls????? Hope this info helps or interests some of the 25 owners. Finally got the boat together!!!!! THANKS TO KEITH EICKERT!!

Cattitude · 05-13-2002, 11:52 AM

Bo, last i knew, Chris at Stern Drive Specialists in NY had a couple 1/2" spacers which worked well on my 25 Daytona twin step. I tried the two" shorty also but had the same opinion on planing results.

A five blade hydromotive is likely the ticket for our boat though i have not tried one yet. I have not even run my labbed Bravo 30 yet! I did try a 26" hydromotive last year while my 28 bravo was being labbed- I could not even get on plane- the blades are considerable smaller on the Hydro. Good luck! Call me if you ever want to talk set-up- 479 636 4669.