• If you log in, the ads disappear in the forum and gallery. If you need help logging in or getting registered, send request to: webmaster@southernairboat.com

gear box for a warp drive

S

stan

Well-known member
gota 14x8 hull with an eight blade warp drive @78 inches gona hook it up a sbc that produces 490 ft lbs of torque at 3000 and 565 horses at 6200 r's the way I figure it a 2:1 will be most efficient use considering 6200 max rpm.don't know for sure if this combination will give me a strong hole shot can't afford to buy boxes to experiment with kinda like to hit the nail on the head the first time out .If not a 2:1 what ratio will bring this boat out the quickest ?any suggestions would be appreciated
 
IF YOU GOT THAT MUCH POWER, YOU BETTER STICK WITH THE 2:1. IF YOU WANT TO GO ANYMORE THAN THAT LIKE 2.37 OR 2.68 YOU WILL NEED A MUCH BIGGER PROP.
 
Thanks hmgm123 thats what I kinda thought .I have never had this much power to work with before.
 
stan":1e9le4vj said:
I have never had this much power to work with before.
Click to expand...

come on stan that caddy was always wiating for you to give er hell.but you never wanted to scare the dog. :D
 
When i was runnin a dd caddy had a 6 blade turnin 2800, made a few mods to the motor and ran 3100 at the same pitch, there was a big noticable difference in performance at the higher rpm, in my application the more rpm the better the warp drive performed, but i'm sure there is a cut off point at a certain rpm, warp told me cavitation starts at sum point above 3000 rpm.
 
I figured if any one would you would know that sbc stands for small block cadillac .been tryin to get the dog ta fetch frogs cept she wants to drive instead
 
Hey stan,PM airjack.He just took a warp drive off his boat turning it about those r`s he can probably give you some first hand insite
 
you can also check with dantehairboatman we where talking 8 blade setups the other day he could probably give you some insite on that before you spend the money on a ox
 
yes budman for a pump gas motor I have exceed my knowledge of what to do just don't have the warm and fuzzy that the 8blades are enough to hold the motor back
My fellow airboater roho runs a 2.68 with the same prop set at 13 degrees behind a 425 no more than 450 horse @ 5800 .We were out sunday jugin his boat and along came Budda Man and kinda what thunder posted elsewhere we wanted to see how the boat ran with some help.Now Buddas boat is set up with a Scramble Town 355 maybe 375 horses 2.38 and a six blade set at72" with 14 degrees of pitch .Budda took roho out of the hole by 2 boats and it took all roho had to beat him by a boat lenght that's what got me to thinkin about this combination tryin to get it right. I appreciate all the advise fellers and I rekon we'll give the 2.68 a chance.
Wildcard I do believe you right about Melford ,he definatley knows his way around a small block .Cept hes out of the equation for right now
 
I ran the 8bl in a 12bl hub 2 at a time stout sbc 400 2.38 at 12 and 14deg was good out the hole with a sick top end. went to the 2.68 14 16 deg it would stretch your neck out the whole. it was 80in. both set ups were a blast. turned the motor between 5400 and 6000rpm. I will have a rebuilt 268 and 255 at the swap meet and other ratio's if you want one. i will work with you to get the ratio right holler at me. :wink: hope this helps. is this going on your alum. boat or glass?
 
wanted to go to the swap meet but obligated ourselves to the lake George cleanup.but I know were you are petunia. The 2.55 sounds interesting for sure.How many horses was your 400.On glass
 
Joe":12bceipe said:
Hey stan,PM airjack.He just took a warp drive off his boat turning it about those r`s he can probably give you some first hand insite
Click to expand...

JJET (AKA) The coffeeman,
coffee2.gif
has a 2.12 and 8-blade Warp, not sure what rpm's he turns, maybe he'll chime in also. I run a 2.68 and turn 6600, @ 13.5 deg. And that's running nitrous so the hp would be around 600.
 
I suggest using another ratio besides 2:1. You have nice engine power and 8 blades so go with a 2.37:1 or maybe a 2.68:1. Either way keep the tip speed down and increase the torque at the propeller.

Rotator Gear box torque based on your Engine HP/Torque numbers at the propeller hub (disregard gear windage and inefficiencies):
2:1= 980ft-lbs
2.37:1= 1161ft-lbs
2.68:1= 1313ft-lbs
3.26:1 = 1597ft-lbs

Build a boat that goes ANYWHERE! We do this application on a daily basis, hope this helps.

Jay
 
You must log in or register to reply here.
Back
Top