camshaft and distributor

[bigboybodry]

thanks for the input!!!! I am calling the cam guy to see if they want it also set on 0 endplay.

Ok I am a big boy what's up with the geardrive?

[GMR-PERFORMANCE]

For the track you may get away with it..

The issue of harmonic vibration has been long a contentious one where gear drives are concerned. No matter how well engineered they are, all gear drives have a certain amount of clearance that causes their telltale gear whine. That gear whine is indicative of high frequency vibration, which can work its way through the camshaft and into the valvetrain. Some contend that such vibration can damage camshafts, valvesprings and rocker arms. Even so-called "quiet drives" aren't free of a certain amount of harmonic vibration.
please keep in mind that i'm not an expert in this subject, but here's my two cents. i have done alot of research on the subject, and here's some of the stuff i've found:

timing chains - proven, reliable, and inexpensive. they will meet or exceed the needs of most applications, and have few drawbacks. they do stretch over time however, but in most applications, this isn't even a concern. newer materials and chain designs have made this proven performer about as good as they can get. only real problem is having to take the front of the motor apart to change cam timing.

"floating" idler gear drives - (pete jackson, etc.) there is much debate over these types of drives, but here are some facts. yes, they do transmit harmful harmonics to the valvetrain. these types of drives also take the most hp out of all the drives to turn. reason for this is because the dual idlers actually "wedge" themselves against the crank and cam gears while they are turning. friction costs hp. yes, they can cause valve spring failure, but this is in extreme cases and usually the end result of many things rather than just the one, although valve spring failure with these drives has been higher than other types. i'm not sure if they can limit rpms, but they are not designed to turn over 7000. heavy valve springs and high rpms can cause extreme loading on the idler gear bearings, which can lead to possible failure. i personally don't know of any cases of this happening, but the potential is there. the higher the rpm, the higher the gear loading, due to design. some advantages to them? very easy to install, gear whine some of us love, inexpensive, and very reliable in most applications. timing will vary just a bit due to clearances in the gears, but again, very little. when used for mild applications, most users won't see any problems.

fixed idler gear drives - (milodon, donovan, etc.) more expensive than dual idler gear drives, but less expensive than belt drives. after speaking with engineers at milodon, most valvetrain harmonics are absorbed by the cover into the block. i can't verify this claim, so it might be open to debate. ROCK SOLID timing. additionally, when PROPERLY set up, fixed idler gear drives will take only marginally more hp to drive the cam than a belt drive. (5-7 hp at a 1300 hp level.) they will run at virtually any rpm your engine can run at. gear whine is not nearly as bad as a dual idler setup, and cam timing can be easily adjusted by removing the front cover. biggest drawback to these is installation. if you don't install them right, you'll have gear clearances wrong, and can damage the gears or have other problems down the road. best to take your time and read the directions carefully, or have a pro install it for you.

belt drives - the standard by which all others are measured. also the most expensive. installation is more difficult as well. advantages? takes the least amount of hp to drive, actually absorbs harmonics from crank and valvetrain, externally adjustable cam timing. reliability is proven, although belt replacement is required at certain intervals depending on use. a big drawback to them though is that the belts DO STRETCH. according to Jesel, belts can stretch as much as 10 degrees. timing belts also don't like oil contamination, and require replacement in case of seal failure or other oildown issues. when the most hp counts though, belt drives are the way to go. is the extra cost worth it though? in my opinion, not unless you're in professional competition, or in a racing series where you need every advantage you can get. for something like 8.90 or bracket racing, there might be a reason for it, but you can still get your consistancy without them. to me the extra money you spend on one can be better spent somewhere else.

basically, it all comes down to preference or application. for me, i prefer fixed idler gear drives for most applications (racing), timing chains for just about everything else. i'll use belt drives if requested, and will use them for all out motors where no expense is spared. i will NEVER use a dual idler gear drive for anything other than a paper weight. if a customer wants one, i'll build the motor with a chain, and they can install the gear drive.


Just a bit of info hope it helps you.. Myself look at the cost and pros and cons.. A good double roller will get the job done all day long and for the most part not effect anything enough to have the normal racer even think twice about it... If you are building a all out race car then its simple jessle belt drive and eat the cost.

[bigboybodry]

it makes sense and thanks for the input! but I'm not looking to spend 1k plus on a new timing setup.

[bigboybodry]

Well I had picked up a jesel belt drive for the camaro motor and had a adjustable double roller before I purchased it so I guess I will install the double roller chain instead of the gear drive?
Posted via Mobile Device

[bigboybodry]

something like this would be better?

[bigboybodry]

It's alive !!!! It's alive!!!! and sounds awsome with the new custom cam. I turned the block in it yesterday rode through a drive in car show at the sonic beating up the concrete. You would have thought I was riding in a lambo all the people looking HaHa. Wish you guys were here to enjoy it with me. I will borrow the wifes ipad and get a video up later tonight my phone doesn't pick up the sound that good.

I went with the chain guys and wanted to thank you all for the input!!!

[bigboybodry]

My ride with the new cam installed https://www.youtube.com/watch?v=87tm...e_gdata_player
Posted via Mobile Device
Posted via Mobile Device

[Captainfab]

OH yeah! that does sound good

Sounds like it ought to run as good as it sounds.

[redsled87]

Sounds real good. What size wheel and tire are you running on the back?
Posted via Mobile Device

[bigboybodry]

16" wheel and that tire is a 29 18.5 15 but the slick I have been running is a 31 10.5w
Posted via Mobile Device