KNOT-RIGHT

Will this combo make or come close to 600 hp???
please respond


540 bowtie block tall deck
lunati crank 4.250 stroke
manley h beam rods
ross racing pistons flat top
merlin rectangular port cast iron heads
merlin single plane intake
crane hydraulic roller camshaft #hr-296 112 lobe sep 610/632
9.5 compression
comp cams roller rockers
holley 1050 dominator
msd ignition

rws

Here is a link to a thread pertaining to 540's
http://www.offshoreonly.com/forums/s...ghlight=bowtie

Check it out

Rob

formula31

9.5 compression with flat top pistons? What is the combustion chamber volume of the heads?

KAAMA

caveman, I would say you'd be right in the ballpark---very close to 600hp with the parts you have listed. Are you going to do a pocket/bowl port on the heads? Have fun.

KNOT-RIGHT

Bore 4.500
Stroke 4.250
head 119cc
gasket thick.038
deck height in hole .0017
valve pocket in piston intake only -.28
number of cyl 8

9.54:1

KNOT-RIGHT

These motors are existing and running well approx 70 hrs
there are very minor porting done to the ports and some blending in the valve pockets.

never dynoed the engines and cannot get the boat to pull
past 5100 rpm at 89mph

The sad thing is this boat was featured in march 1985 powerboat magazine ( on cover) as a 103 mph Hustler 32 le

equipped as tested
630 hp eliminator 540.s @6000
1.33 to 1.00
Arnesons 1600 asd 8 with 16 inch drop boxes
spinning 17.5 x 28 4 blade rollas

Rik

Have the engines always stopped pulling at this 5,100 rpm? What is the max rpm? 6,000?

6,000 rpm would certainly put you at over 100 mph if you can get there without over trimming the drives.

If the engines are performing correctly, your primary problem here is the 17.5" diameter. Have you tried any other propellers? Smaller diameter? A new set of Mercury Lab Finished SSM#6 Propellers will get your rpms up significantly over a set of propellers that are at least 15 yrs old.

bobby daniels

that cam could be doing it I'm not sure but I'd be very careful turning a hyd roller past 56 or57 hundred and I agree those props would be tough and another thought if the valve springs where not great when new they may be going away with those heavy rollers ,just some guesses


Also I think the comp is 9.10 not 9.54 but that quick figuring

The more I think this cam is the 741 I've used alot in 502's and its to small for your app. even on desk top dyno
I'll try and scan for you but never tried from work !!!

KNOT-RIGHT

I just got back my props from my wheel guy he is well aware
of the rpm problem He cut back on the diamiter to 16.75
and said he added a little more rake and cup to the trailing edges
have not had oppurtunity to run yet do to horrid wet weather up here.

I have been chasing the 100mph mark on this boat for three years but never able to turn past 5100 Maybe the Big blocks are
not producing 600 hp

the 17. 5 diamiter rollas were used on the boat in 1985
with 600hp each engine and it achieved 103.

Weight was 7500 lbs in 1985
I will weigh this boat now to see where im at.
at speed the boat is stern high bow high attitude notice next picture this shot was taken at approx 75mph notice attitude.

Then when you read PB article on this hustler it had over 20 feet of wetted surface.

There is not much support lately on arneson equipped deep vees

KNOT-RIGHT

thanks alot for the replys I do alot of reading on this oso
and I beleave there are some knowlegable people here.

Thats why I am posting this dilema. any information or help
will gladly be appreciated.

Even at 550 hp each engine which even a sick 540 should produce
the numbers work @ 7500 lbs

The exact cam is Crane # hr-296-2s-12 ig
@.50 234int. 242exh. 112 lobe sep gross lift is .610/.632
with 1.7 comp cams roller rockers