User Tag List
Results 136 to 150 of 186
Thread: 21 Rally Sport make over.
-
10-28-2015, 05:03 AM #136
-
10-28-2015, 05:09 AM #137
-
10-28-2015, 08:38 AM #138
Thanks for the kind words! Yes, they will be singing for sure.....
I also know you are a 225PM fan......[/QUOTE]
What did you tighten the heads to 34? And whats the revs 7500? Should run real nice with a pair of 28,s A buddy and i have been trying the 28 drag3 out of Sody Daisy. mine is stock his has a little tip cup. His carries his GS with the tip better than mine. With a 2.5 245 on his GS he got 95+ last week. i could only muster 94. I would think with tip cup they would carry your boat very very well! We also tryed 28 et,s and there was no comparison in acceleration and how the props carried the hulls. Even my stock Drag3 was way better. Just a fyi if your interested.
-
10-28-2015, 12:10 PM #139What did you tighten the heads to 34? And whats the revs 7500? Should run real nice with a pair of 28,s A buddy and i have been trying the 28 drag3 out of Sody Daisy. mine is stock his has a little tip cup. His carries his GS with the tip better than mine. With a 2.5 245 on his GS he got 95+ last week. i could only muster 94. I would think with tip cup they would carry your boat very very well! We also tryed 28 et,s and there was no comparison in acceleration and how the props carried the hulls. Even my stock Drag3 was way better. Just a fyi if your interested.
35CC's, limiters removed but I do not plan to prop for more then 7250 with small rods.
I have been looking to get 28's but it pulled the 30's well.
I think this boat needs Cleavers to give it some transom lift due to weight back there. Certainly does not need bow lift. I think flying this boat straight will be key to achieving good performance.
I'm also looking for 30 ET's because they are a castrated Chopper which will keep the bow from flying loose and they also worked well on my Howard.
Thanks again for the FYI!
-
whipper liked this post
-
10-28-2015, 04:06 PM #140
Yes i see since there's 500hp and 800 lbs of motor and trim brackets the cleavers are a great choice. What's interesting is the power to weight of the twins is the same as with a single at around 0.7 hp to 1 lbs. 245- 250hp at 350lbs each. or twins 500hp to 700lbs is 0.714 hp to 1 lb. A single 300 XS at 310hp is .614 hp per 1 lbs at 505 lbs . So two moving the same mass, just guessing but hull weight of the 21RS might be what 1400lbs at the most? So theoretical at 2200lbs rigged with twins power to weight is .227 to 1 hp. With a 300xs at say 310hp rigged at 1905lbs power to weight is 0.163 hp to move 1 lb of mass. Your power to weight with your choice of power is going to be very good compared to a single 300xs even though your adding an extra 300 lbs. She will accelerate like having a 225pm on the back of a 700lb Vee hull.
I calculated this to understand how 30,s would work and its easy to see why now. For example my GS with a 225pm is 0.172 hp to 1 lb. interestingly your power to weight will be the same as an Allison RR at 650lbs with a promax on the back. .227 to 1 also!! Thats useing only simple weight measures as there not on a scale right in front of me. I went Allison RR at 650 lbs motor is 350lbs HP with tunner heads and flywheel 250hp pluss 100 extra lbs for jackplate =1100lbs Use the same formula for all the comparisons close enough to see your going to have a quick accelerating 21 Rally sport to be sure. With no rev limiter I would find a pair of 27 pitch props and let her eat!!
-
10-28-2015, 05:17 PM #141
Heck, that info is a bit toooo technical for me....... I need to reread that a few times and digest it a few more times before I get it..... Not to mention a need a calculator very handy.....
Also keeping in mind correct weight placing for CG is important for good attitude and balance is a factor!
-
10-28-2015, 05:30 PM #142
20" to 15" comparison.
20" setup with 40amp system.
New 15" setup with 16amp system.
-
Frank Molé liked this post
-
10-28-2015, 05:53 PM #143
What a difference. Powerheads won't be jacked up in the air when running now so that lower cg will help with handling.
-
10-28-2015, 05:59 PM #144
-
10-28-2015, 06:00 PM #145
Much meaner looking always LOVE the 15 inchers!! Basic interpretation on the other post your going to have one quick 21fter!! haha
From a {reliability} standpoint and power to weight there are no better pair than what you have done. Sure 260/280/S3000 same weight more power but wont last 1000 hrs like a promax will.Last edited by whipper; 10-28-2015 at 06:46 PM.
-
tux974 thanked for this post
-
10-28-2015, 07:09 PM #146
-
tux974 thanked for this post
-
10-28-2015, 08:33 PM #147
Looks awesome and finished ? Let's get her in the water !
1990 22' Activator Yami HPDI 300-sold-86.4
1976 21' Challenger 2002 3.1 Yami 250 Vmax phase lll 89.7-sold
1982 21' Superboat 300merc-87
1990 22' Activator yami OX66 Vmax 250-84.2
1982 30' Scarab-twin 200 Merc-sold
1979 21' Challenger 300 Evenrude-sold
1979 21' Superboat 200 Merc-sold-72
-
tux974 thanked for this post
-
10-28-2015, 09:33 PM #148
Beautiful rigging work. Can't wait to hear how it handles, not to mention, accelerates... Awesome.
You cannot bring about prosperity by discouraging thrift. You cannot strengthen the weak by weakening the strong. You cannot help the wage earner by pulling down the wage payer. You cannot further the brotherhood of man by encouraging class hatred. You cannot help the poor by destroying the rich. You cannot keep out of trouble by spending more than you earn.
-
tux974 thanked for this post
-
10-28-2015, 09:49 PM #149
I can't believe I missed this one as well,great job Tony,very impressive .
21 SuperBoat VF200 Yamaha SHO
Bender Clan memberEroshibend Yamamoto
2015 King of the Cut
2016 King of the Cut
2017 King of the Cut💪
-
tux974 thanked for this post
-
10-28-2015, 10:20 PM #150
It would be a crime if this doesn't get wet before the weather gets nasty.
-
tux974 liked this post
Similar Threads
-
Rally Sport 21
By 99fxst99 in forum General Boating DiscussionReplies: 21Last Post: 11-15-2020, 08:44 AM -
21' Rally Sport
By southern preservation in forum Hulls up to 20'Replies: 2Last Post: 11-01-2013, 02:33 PM -
Roll Call!!!!!!!!!!!! Who's gonna make the Smiths Bend Rally
By 2 De River in forum General Boating DiscussionReplies: 77Last Post: 07-01-2004, 10:43 PM