Velocity Stacks, do they really do anything?
04-08-2007, 05:47 PM
#1
Senior Member
Thread Starter
Join Date: Sep 2006
Location: Eau Clare,
WI
Posts: 384
Likes: 0
Received 0 Likes
on
0 Posts
Velocity Stacks, do they really do anything?
Do velocity stacks increase performance in any way or do they just look cool? I seem them in every nice looking modded boat, and since I am buying a new G260 stocker I am wondering if that would be a cheap way to add a touch more performance.
04-08-2007, 06:21 PM
#3
Senior Member
Join Date: Sep 2006
Location: The compost heap of theKent, UNITED KINGDOM
Posts: 794
Likes: 0
Received 0 Likes
on
0 Posts
RE: Velocity Stacks, do they really do anything?
velocity stacks / spit tubes whatever you want to call them work on gas/petrol motorcycles so i cant see why they wont/dont on the gas/petrol boat engines ????? smoother airflow increases power .
04-08-2007, 06:27 PM
#4
Join Date: Apr 2006
Location: Augusta,
KS
Posts: 1,983
Likes: 0
Received 0 Likes
on
0 Posts
RE: Velocity Stacks, do they really do anything?
In the hull in building a V-stack wont even clear the cowl ,nd If you really think about it, no they dont do any more than the carb already does as there is a taper to the intake side of carb, polishing the carb intake side would do more than the stack as it would smooth the flow of air comming into it...Even that really wouldnt be worth the effort....
04-08-2007, 11:08 PM
#5
Senior Member
Join Date: Aug 2002
Location: ,
OR
Posts: 1,428
Likes: 0
Received 0 Likes
on
0 Posts
RE: Velocity Stacks, do they really do anything?
most actually reduce intake air by as much as 10%, but the one pictured will increase air flow by as much as 8% over a stock carb opening
04-09-2007, 06:25 PM
#7
Member
My Feedback: (2)
Join Date: Jul 2003
Location: Ore City,
TX
Posts: 39
Likes: 0
Received 0 Likes
on
0 Posts
RE: Velocity Stacks, do they really do anything?
Long Stack May help low end torque a little but not really on high end old&slow has a good suggestion for top end power at the rpm these motors are running but the stack will cut down on intake slobber inside the hull.
04-10-2007, 07:52 AM
#9
Senior Member
Join Date: Aug 2002
Location: ,
OR
Posts: 1,428
Likes: 0
Received 0 Likes
on
0 Posts
RE: Velocity Stacks, do they really do anything?
the tuned intake length for a modded zenoah with an intake timing of 155deg is 3 13/16" that is measured from the piston face to the end of the spit tube. so you will ned to add just about 1/4" of spacer material under the spit tube base. problem is most boats run out of room for any kind of stack very quick, so your better off to do the best job you can at reprofiling the carb intake and give it a good polish. i had posted the complete intake list at one time the worst being a straight tube and the best being what i posted above
