Tony why stay with 510 ci, why not increase displacement for more torque, and lower rpm for more reliability, everything else more or less 750 spec. If restrictor plates can govern the max output anyway, then this seems to me to be a way to have an alternative 850 engine package.

How long do the 750s normally last when racing?

Guy absolutely...i think a head .change would do great..i talked to mike from sterling back in septmber on this..class one uses the restristor with some success..we just have to run a couple times to fine tune it...
the biggest restrictor u have to deal will be Mauff...he didnt want to race me before or tom....

we ran 1 motor 5 races with 1 valvespring change...3 is probably best...valvetrain only issue with this combo...if we change the head we lose valve weight...it will certainly help...
we have never had a bottom end issue..bearings always come out like new...bobbyb a guy like Dean can do this package pretty reasonably. and there are some cool boats out there

Dave yes I'm pretty sure it was the new mtor..he had 3 built he was playing with..they are pretty cool pieces...th 30 hp is close...like i said his 464 made more torque than my 510s..

tony, let me know when supercat racing adopts a new rule change. then haul that 388 to ft myers and we can try the 566's in that skater!!!

what about if we look at it the other way, what would the 750 guys want an 850 boat to do to run with them?

the DW is back up and running after taking a swim in KW. Looking to take on all challengers this year.

How was testing ?????

Tony,
Thanks for the information.

the motors should last a full season. springs should be checked often to see if all the closed spring pressures are the same (easiest way to find a broken spring or inner spring). the springs are the weakest link.

the "restricter" would possible bring the motors closer but you would need to put these engines on a dyno and see how they react to the restricter. just restricting airflow with the same size restricter will not bring all the motors down to the same hp. the blower motors and a motor with more cubic inch will produce more torque. torque is somewhat based off cubic inch, so you can only make so much torque per cu. in. no matter what compression ratio or cam. forced induction is really the only other way to increase torque, like using a blower.

lowering the rpm limit would help save the valvetrain but a 7600 rpm isn't a unreasonable limit for these motors. we are talking about race motors in a race boat.

lambo's spin 8600
nascar 9500

Sean i would let them run and work with the restrictor later..i want SUPERCAT to allow Mercury to use what they want if they want to run...This Mercury only deal is stupid...Catlite class is great for a class like that...Everybody shouild be allowed to play...Remember Mercury was willing to build the Supercat motor again..Lets just run them again together...Sean Key west was weird for the 850s...WHM never ran so good and u guys really never ran that bad...we just need to keep doing it till we refine the package...

bobbyb your welcome anytime..get a hold of me if u need anything...scotty hows Fla...it was minus 11 this morning here...

Tony why don't you and Jimmy vote to change the OSS 750 class rules to allow 850 boats in your class.............