whipper
Well-Known Member
More food for thought. At 90 the air is just starting to make it over the back seats in a GS. If you have the power to run past 100 ask anyone with a GS the different feeling they get right around 100. The hull takes on a whole new set unlike any other speed. The aero dynamics of the top and bottom along with the hydrodynamics are working together to cut threw the air and water as one grasshopper. The air speed is clearing the cockpit no longer creating that turbulent and running off the back deck. The motor is now the new source of drag. My guess is if someone put a race hatch with a taller cowl deflector on a GS with a strong 260 it would feel better at 104-106 than it does without. Ziemers 260 is a SS so his cowl is lower at even than a 20 inch that would have more cowl higher up catching air. Todds GS is a 20inch 260 and also runs at that 104 mark along with most guys with a 260. So whats stopping the hull at those speeds? Is it power? Or is it aerodynamics? Probably a little of both. Most say its the larger Frontal area and or beam of the GS over say the 02. BUT there is only 1 inch difference from the SS that can run 110+ with the same setup and 1 inch less in over all length. The cockpit is way smaller in the SS, the cowl is way taller on the hatch on the SS to stream line the air past the cowl, and hull is the same deadrise on the SS but the SS is almost 200 lbs lighter. So yes there is a little more frontal area but there are alot of other things going on also that might be improved on to help the GS CUT threw the air a little better. The higher speeds with the SS with the same power is weight more than anything until you get to the past 100. There the GS need more and more power to go any faster than 103-104 because everything starts to work against it more than the slipstream SS,XR, and 02. Much controversy over the guy buy me who ran 110+ with his 335hp 300PM. but i talked to him quite allot over the phone asking him how, why, why you think is why, ect..haha He said it was the sheer torque of the motor over the 2.5,s that made the GS go past that 104-106 mark so many cant go past. Not saying thats a good idea for anyone to ever go past 104 in a GS. He also said it ran better with more weight than solo. To flighty at those speeds solo. The weight helps to off set the drag created at the cowl throughing the bow around perhaps? At any rate the HOOKING element of all this mumbo jumo is that there are different stages of state these hulls ride at and each one creates its own temperament when coming OFF speed. Knowing your hull and the feeling at each point on the way up will help you on the way down also. Just like we all know in that 60-67 mph range depending on what you weight that feeling of climbing on the pad then lip then take off!! At 230 it starts to happens for mine right at 66 with a half tank. If your weight is 170 it might start to happen at 63 and by 67 you blink and your at 75? But I know when coming down from speed im pretty safe when i reach that speed. For the most part. haha Ive had the bow dig in at 45-50 while still decelerating because my trim was still to high hearing the ratcheting case clicking. But thats an easy fix. You just stab it and trim down a little to get back to normal then let off again. You need to get the prop biting again is all there. know your boat inside and out treat her right and she will look after you. i dont know about you guys but I talk to Allison all the time.:big grin She will let ya know when your being an ***!! :beer: Maybe I shouldn't have told ya that ,ya all might think im crazy.. to late.
. I look more like the pic in your sig, whip.
I think the two hulls would perform closer than anyone suspects adding a race hatch up to the buckets in the GS and a fin to stream line the air to the cowl. Not that anyone should ever even attempt to ever do that and see if it works. That could spell life ending results. {disclaimer} Its pretty clear though the differences with same angle pics back to back like the pics above. As you can clearly tell theres still ice on the lakes around hear and the ski hills are shut down for the winter and I have way to much time on my hands.:banghead It was fun and interesting for me though to look at the two related hulls. It makes looking at the other faster hulls what makes them so fast!! The XR2001 is just a pure NASA rocketship by comparesin!! The XR02,s stream lined and super light shape. and the XB2002 same with the small centre windscreen and narrower profile and hull configurations. 
