What are the advantages or disadvantages of running one of these. From the little information given by product description I have never really heard of the good or bad. IF you have had experience please let me know.
Good- They won't wear out like a chain or a belt They're not too expensive They're loud Bad- They transmit harmonics from the crank to the cam Parts are not easy to find, adjust, or repair quickly They're loud ~Scotch~
Gear drives are only better cause they provide accurate timing under any load or circumstance. Unlike single or double timing chains that will stretch over time. The new timing belt kits are almost as good as a gear drive considering they don't have the noise like a gear drive. Thats just what I know. I would go gear drive.
Certain "timing" style belts, and in particular, one of the Harley drive belts are very tough. Kevlar or similar materials. I have used this type on a welding fixture for a Ford supplier w/good results.
I bought one for my Falcon ,but i havent put it on yet so i cant tell you.I dont have a single oil leak anywhere on my motor (and i have a chrome oil pan ),so i am reluctant to pull the cover and drop the front of the pan and create a leak...
I have a gear drive in my hotrod.....there are different ones and some you can barely hear.....some are better than others. I'd stay away from the cheapie $100 ones.... There are gears in other parts of your car that are also transmitting some harmonics as well.....not a big issue. The ones with a fixed idler are smoother running (and more $$$), but may require some machining to the block....the dual idler drives rob a little more power than a chain, as the crank is forcing the idler into the cam since it 'floats'..... I've used dual idler gear drives in a few engines with no problems.....many people will say gear drive users are just trying to get that blower sound.....but that's not it....it's just another way to turn the cam..... Hotrods are supposed to be noisy....right?
Thanks for the answers. Had an old timer tell me that they rob too much power while at the same time thinking of the stability in timing. Trying to make a decision between getting a gear drive to try something different, or spending the cash on the needed pieces for a tunnel ram.
i've had a couple pete jackson style g/d.....i've heard that a "quiet" one will eventually end up as noisy as a regular one....(not sure on how much of that was truth...) as for noisy.....i had a summers bros. 3 gear setup....that thing was like a trip to the dentist... you usually got out of the car with crickets in your ears...... brandon
I have a "noisy" Pete Jackson in mine along with a Rockcrusher Muncie which also makes some racket. Along with the 4.88 gears and straight through Cherry Bomb header mufflers (with no rear exhaust) the car is noisy. I like it that way. I will say I have a cast aluminum Cloyes timing cover which I believe masks the gear drive noise a tad. It also required machining down the center pin a little to fit (The Pete Jackson is designed to be installed that way and has instructions on how to do it). It doesn't have to be precision machined, just ground down a little for a snug fit to allow clearance and eliminate walking fore and aft. Some stock tin covers actually allow the gear drive to move forward and back too far and I know some people have alleviated that by welding up the center pin or tin cover a little. Others have just stuck it in as is with good results. Most people either LOVE the sound or HATE it and will not be shy about saying so on the forums, though I have had nothing but positive comments about the sound of my car in person.
I'm the same noise doesn't bother me much because I'm still young and a little strange with all my hearing. I'm planning on throwing this into a BB Mopar that I've had for a while. The insides looked great but for some reason timing and cooling are keep hitting me out of nowhere. I know its a costly part but I rahter have replaced it than brake down.
I had a gear drive in my '62 for a while. It was a noisy, cheap one. But at the time I wanted that noise. I would hear rods that had them and I liked it. At first I loved it, then after a while it got on my nerves. I would probably still have it now, but like I said it was a cheapy and one day it fell apart on the freeway going down to Albq. So I drug her home and put a double roller in it...I like it much better now... I still like to here the whine of a gear drive, I just would rather hear it on other people's rides...my $.02
Are the queit one just as bad harmonicly(is that a word?)is it th harmonics of the gears ,Crank or other. and what "Damage" do they cause?? and how quiet are the quiet ones. I would like to know as well Im not tring to hijack but Ill get repremaned by the post police if I post another thread.
think car craft did a tech thing on chain vs gear drive .....seems like it was sometime last year..... brandon
In the early 70's, pro-stock cars actually ran double roller timing chains because it advanced timing at high rpms. The only time I would use a gear drive is when the valve spring pressure is so high, as in a mechanical roller cammed motor and it was street driven. Just my .02
A chain RETARDS the timing at high RPM...as it stretches....the cam comes "on" later... Most older cars are running around with retarded cam timing as the chain has stretched.... The noise of a gear drive comes from the straight cut gears, the mesh or cut of the gears, and the air that escapes when the gears come together produce the whine....
if you plan on driving the car forget the gear drive the noise will get old fast buy a good quality true roller chain the cheap double row chains stretch fast. I put a new double row chain in my chevelle drove it two hundred miles and you could just about take the chain off the gear set , glad I decided to do the cam swap.
the sbc. in my nova had a Pete Jackson gear drive in it for the last 8 years, the noise got to be a pain in the ass, the motor started dropping oil pressure i pulled it apart and found that the front cam bearing was going away, i talked to a few hardcore motor guys i know they all told me that any gear drives they have used had this problem, i racked up about 10,000 miles on my car the motor was fresh when i put it in. i would never run a gear drive again. i had bad luck with mine....
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