Jessel rockers
 

anyone know of a good source? and are they worth all the xtra $$$???

Re: Jessel rockers
 

high-tide, you have a real way with words! Seriously though, I totally agree with you. Just my .02--Lou

Re: Jessel rockers
 

Hello, I have the Jessel system on my drag race car which has a big solid roller cam and very stiff valve springs. My 2002 Nordic Heat is running a 598 with a pretty big solid roller and psi valve springs with a lot of seat pressure,and I run the T & D system on it, which is pretty much like the Jessel but a little less money. On these applications these types of rockers provide great durablity. I agree with everyone else, if you are running a smaller cam and not a lot of valve spring and I probably would not spend the extra money. At the end of last season most of the valve train on my Nordic was trashed, so that is why I swithed to the T & D rocker system and the PSI valve springs which are factory cryo'd and triple heat treated and then we coated them in house with our antifriction coating. I will let you know at the end of the season if it was worth it. Good Luck to you! Glen

Re: Jessel rockers
 

cryoracer-- Sounds like those two motors really bark. Just out of curiosity,what kind of drive setup is behind that 598 and has it held up?

Re: Jessel rockers
 

Lmarth-- I am running a stock length BMax with 1.3 ratio and a stock 30 pitch Bravo, but I am looking into the new Hydromotive 5 blade, if you look under the Nordic forum you will find my discussion with Nordic Heat. We first put this engine in last year and broke the Bmax twice. I broke the vertical shaft the first time and the coupler the second time. Dean was very nice to me and did not charge me and sent up a fresh reconditoned drive. It has been fine ever since, I have about 26 hours on it with the big motor. I think some of the problem may have been that I am use to taking off in a 9 second drag car. Can't do that with the heavy Nordic. I have learned to be very gentle with the throttle until there is enough speed and I have it trimmed out, then I can lean on it. The downside of the Bmax is the power the bigger gears rob, but it is worth it to me to keep the drive together. I forgot to tell you the 598 is an EFI quadrotor motor and there is a lot of torque. Drives do not really like that a lot! Hope she contiunes to hold up. - Glen

Re: Jessel rockers
 

Glen-- I need a minute for this all to sink in- A Nordic Heat with a solid lifter, EFI, Quadrotor 598 ??? I'll bet you surprised a few "hot boats" with that set-up! You're probably working on the marine equivalent of wheelie bars! High-tide- don't misunderstand my comment. I loved your post- short and to the point!--Lou

Re: Jessel rockers
 

Dyno,
Their is no deal on Jesels. Mark up from WD to retail is not much. I would go with the competition series with the oiling and not the SS series. Boats are like drag cars, we run for long periods of time.

Chris

Re: Jessel rockers
 

thanks for all the info...sounds like with my dinky little flat tappet hyd. cams I can stick with Cranes and keep my money for other stuff.....

Re: Jessel rockers
 

Personally, I would not use Crane rockers. I prefer Comp Cams Stainless rockers, they have a much bigger bearing that would most likely be more durable. I am going with those for my 540 build-up.

Re: Jessel rockers
 

I've used Cranes,Comps and Harland Sharps in the past with fair longevity with all of them....they seam to go about 300 hours and then show signs of wear.

Re: Jessel rockers
 

Thanks Lmarth-- True we have surprised a few. We modified the hatch just a bit and it looks stock when you first see it. My Buddies all give me a hard time because a lot of the time we are just out crusing slow and we keep a lot of stuff up under the cuddy. It really is a family boat, we just put some umph behind it. Fun in the Sun!

Re: Jessel rockers
 

Your better off with an aluminum rocker. Yes they are not as rigid as a steel rocker but they absorb harmonics in the valvetrain. Steel rockers amplify harmonics that is why the Cup boys run aluminum.

Chris

Re: Jessel rockers
 

Chris ....good info I never thought of that....

Re: Jessel rockers
 

Chris--Excellent point!--Lou

Re: Jessel rockers
 

Lou/Dyno,
Well it kinda helps when you use to work for a rocker mfg and have seen the R&D first hand.

Chris

Re: Jessel rockers
 

Wesco wont let a motor go out of the shop with anything else.....

Re: Jessel rockers
 

Cstraub69,

"Your better off with an aluminum rocker. Yes they are not as rigid as a steel rocker but they absorb harmonics in the valvetrain. Steel rockers amplify harmonics that is why the Cup boys run aluminum."

And what type of problems do you see with amplified harmonics, valve float at lower rpm? or damage??

I have been running Crower SS rockers for years and the only complaint I have is they dont properly line up with the valve stems in some cases. I have had to cut and weld push rod guide plates to compensate. Next time around it will be T&D or Jessel or a shaft type setup.. with more fingers and valves to mess with..

Thanks
Dick

Re: Jessel rockers
 

Dick,
The most detrimental was spring harmonics and premature failure of the valve spring. In testing of components by the boys in NC, valve springs would last longer with aluminum rockers.

I would also recommend on any boat engine with 600HP or more to run a single or dual tapered pushrod to prevent deflection. Deflected pushrods rebound after max lift and can cause lifter damage after a period of time. The large 7/16" tapered stuff prevents this and in most cases is worth some extra hp. I had this happen to Jasper engines 2 years ago in a 417 CID SBC dirt engine. You could tell the deflection was happening by the SCFM fluctuation on the dyno sheet. I told them to change the pushrods, quite long, 9.500". Well they decided the next morning to pull her one more time and she spit 2 pushrods out. I had some 7/16" to 5/16" single tapers made for them and the engine picked up 40HP, which for any engine is a sizeable gain.

Chris