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nocigarette 09-22-2006 07:21 PM

gear drive
 
who makes the best gear drive or am i wastig my time and should just go with the jessel belt...................man it is exspensive though///////////

gg10 09-22-2006 07:37 PM

Re: gear drive
 
best gear drive is RCD, run all the time in my boat, Keith black is ok as well, wouldnt run a belt, I like to wash down and the RCD set up right is bullett proof, good luck ,gg10

nocigarette 09-22-2006 07:38 PM

Re: gear drive
 
Where Due I Find It Thanks Buy The Way

Reed Jensen 09-22-2006 08:58 PM

Re: gear drive
 

Originally Posted by nocigarette
who makes the best gear drive or am i wastig my time and should just go with the jessel belt...................man it is exspensive though///////////

Pete Jackson gear drives is a stone's throw from me. But I'd rather run a good roller chain than a gear drive. Jessel belt drives are great for R and D and dyno work, but their life is shorter than a chain. Gear drives impart a different load on the cam bearings. The gears tend to push the cam and crank apart, where the chain tends to pull them together. BBC engines have the oil port for the cam bearings on the "bottom" where the load is placed when running a chain. If you run a gear drive the load is on the top. Some people don't like the gear drives on boats because of the harmonics from the camshaft. Cams tend to "load" and "unload" depending on the cam lobe locations. The energy that is used to depress the valve spring is returned to the cam on the back side of the cam ramp. With a gear drive the gears tend to "chatter" as the energy is returned. Especially if they are straight cut gears and not helical cut. Straight cut gears are more efficient, but by their design the gear faces "impact" each other upon contact and slightly increase and decrease the cam rpm during the contact. That is why modern stick transmissions use constant mesh helical gears. They are smoother and less noisy. I'd suggest you go with a high quality roller chain and forget the gears. Just my opinion.

nocigarette 09-23-2006 06:42 AM

Re: gear drive
 
Thanks Guys

vtec 09-23-2006 08:39 AM

Re: gear drive
 

Originally Posted by Reed Jensen
The gears tend to push the cam and crank apart, where the chain tends to pull them together. BBC engines have the oil port for the cam bearings on the "bottom" where the load is placed when running a chain.

The Nooky man knows his shizzo.

The guys who certify automotive engines for aircraft use will only use a belt where they can put 2 (i.e. a redundant belt) like on the water pump. The belt driven cams haven't met their standard for reliability. But these are boats and not airplanes so.............

And chains have improved in the last 20 years.

scarrab30 09-23-2006 06:02 PM

Re: gear drive
 
Im with reed jenson, been there done that on the others. Brian

nocigarette 09-24-2006 07:18 AM

Re: gear drive
 

Originally Posted by Reed Jensen
Pete Jackson gear drives is a stone's throw from me. But I'd rather run a good roller chain than a gear drive. Jessel belt drives are great for R and D and dyno work, but their life is shorter than a chain. Gear drives impart a different load on the cam bearings. The gears tend to push the cam and crank apart, where the chain tends to pull them together. BBC engines have the oil port for the cam bearings on the "bottom" where the load is placed when running a chain. If you run a gear drive the load is on the top. Some people don't like the gear drives on boats because of the harmonics from the camshaft. Cams tend to "load" and "unload" depending on the cam lobe locations. The energy that is used to depress the valve spring is returned to the cam on the back side of the cam ramp. With a gear drive the gears tend to "chatter" as the energy is returned. Especially if they are straight cut gears and not helical cut. Straight cut gears are more efficient, but by their design the gear faces "impact" each other upon contact and slightly increase and decrease the cam rpm during the contact. That is why modern stick transmissions use constant mesh helical gears. They are smoother and less noisy. I'd suggest you go with a high quality roller chain and forget the gears. Just my opinion.



what roller chain due you suggest

PatriYacht 09-25-2006 07:45 AM

Re: gear drive
 
Cloyes Hex Adjust is good quality and easy to adjust.

ratman 09-25-2006 10:05 AM

Re: gear drive
 

Originally Posted by PatriYacht
Cloyes Hex Adjust is good quality and easy to adjust.

rollmaster timing chains are the finest made period. the metalurgy of the steel in the german made chain is what separates them from the others, as its the chain that streches over time. rollmaster also use billet gears, and the cool part is they only cost a few dollars more then other timing chain sets. ROLLMASTER


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