Hello all, been a while since I posted, but I was having a conversation with a fellow "rodder" last night at a holiday party (while the ladies were talking about the boring stuff). First off, sorry if this horse is in the barn recovering from a whoop'n already. We were talking about motors (we both have SBCs). I was telling him how much I like the sound of a blown motor pulling into a car show or other event I am at. I don't have the finances at this point to install a blower (could probably afford a blower, but need to build the motor to "support" it in my opinion). He said "I have a gear drive and it sounds a lot like a blown motor". That got me thinking (always dangerous)...why not? I have been doing some research on the subject this morning on several different sights and as you might guess...lots of opinions out there. I looked around on here and saw some older post about it, but nothing real recent. There are several different options on price and such, but it looks like for around $200.00 a guy could get everything he needs to install a decent dual idler gear drive. My car will not ever be driven too hard or raced, but being able to have that gear whine for that cost is somewhat appealing. Thoughts? -Bubblehead
I have a blower, and a gear drive does NOT sound like a blower. The guys who are really into fast cars look down on cars with gear drives, the guys who don't know much look up to them. I guess it depends where you want to be?
They do have their own unique sound - not really like a blower and they surely don't stick through the hood! I have a blown 392 with a gear drive (not started yet), that - and the Q.C. rear end with spur-cut gears . . . should be whining like a car load of *****es! Whups - did I just say that . . . not PC for sure!
Thanks Squirrel, understand all. They may not sound exactly like a blower, but similar I guess. Just don't have the funds right now for a blower and the ***ociated/required motor work. Just thought it might be another easy and relatively inexpensive winter project. Although I am into fast cars, don't really need my car to be fast (frankly it is fast enough now). Not sure why some folks would "look down on cars with gear drives", seems like there are other reasons to add them other than the gear noise they provide.
the gear drive i run is quite in my race car. my thinking always was if it was making noise it was making shavings wright or wrong just my 2cents
I get a kick out of listening to the Aflak duck for 15 seconds, but am glad I don't have to listen to it all the time. Unless you need it or can turn your hearing aids off, I wouldn't do it.
To me anymore, an engine with a gear drive sounds less like it has a blower and more like it has.... well... a gear drive. Or maybe a bad power steering pump. One of the sweetest sounds to me is an engine that's just been cold-started with forged pistons and solid lifters. The pistons are a couple thousandths loose and the lifters have a little extra clearance and there's this wonderful, busy, mechanical, musical noise. And then after five or ten minutes when things start to warm up it all fades away. But then I also like the sound of an old Mopar gear reduction starter too...
Been building engines for a living since the mid sixties. An inexpensive gear drive is the single worst thing you can do for a small chevy. Save your money for some real horsepower improvers. I continually try to upgrade my knowledge/skills and attend many schools and seminars on engine building. Back in the mid eighties one of the larger camshaft retailers produced a stop action, dyno and computer generated film on the effects of gear drives on the valve train of a typical Chevy build. After viewing this and seeing first hand the harmonics problems and damage potential. I will not use gear drives. We are not talking the expensive formula 1 exotic car stuff. But the stuff Joe the enthusiast would buy. I have asked why the geardrives are still marketed? The answer is "The kids buy them". As mentioned, the whine gets old real fast. The wear and noise are caused by the angles cut into the gear contact teeth and the "floating" idler gears.
I ran a pete jackson noisy gear drive in the late 90s on a SBC. It was very loud, and after one summer I removed it and sold it. The sound was nothing like a BLOWER, I run a blown sbc now. The gear drives also seem to have a lot of play or backlash in them. I would never run one again on a sbc .
I can name many engines that came from the factory with gear drive cams. IHC gas , ALL FORD FLATHEADS, Ford 300 Six, every heavy duty engine I can think of. The Chevy has problems with them if you do not take care of the radial(fore and aft) movement of the cam. any gear drive kit I have seen has a br*** or a needle bearing to take care of the end play problem in Chevys. There are noisy with the straight cut gears or qiet gear drives available. although I must point out, the factory gear drives do not use the "idler" gears of the aftermarket. I have built hundreds of engines, and I can tell you no matter what chain is used, it gets very loose in a short time. especially with a high lift cam and stiff springs. Put the noisy gears in. if you do not like it, put th slopy chain back in!
My thought if it's making noise it's robbing horse power. You know Grumpy ran the stock nylon timing set to keep down the harmonics in the valve train. The slop in the chain can be remedied buy running your engine for say a few hundred miles then tear it down and reset your cam timing then your set.
A proper gear drive has helical cut gears and doesn't make noise ..the noisy ones are straight cut...also gear drives steal the most power, chain steals less, belt is the best! Posted using the Full Custom H.A.M.B. App!
I have a noisy gear drive in my sbc cause it seemed like the thing to do at the time-if you drive your car a lot- the whine gets old real fast-it is popular with the vehicular 'unwashed' but as Squirrel noted- those who know-know better As for me-never again Posted using the Full Custom H.A.M.B. App!
Thanks guys, starting to re-think this now. It was just a thought and not something I was set on doing.
If I could justify it I would go with the Jessel type belt drive. Quiet and gets a few more HP but I can but a lot of timing chains for $1000.
I see a lot of good reasons not to do it. The "real gear drives" are helical cut gears, are quiet, and don't induce crazy harmonics.
I've said it before and I'll say it again,a gear drive will drive you nuts..it's just noise and doesn't equality to horse power. When I hear a gear drive (which sounds nothing at all like a blower) pulling into a show or the parking lot of the local burger joint I always joke about the car sounds like it has a bad bearing in the alternator! JMHO. HRP
Actually if you are not building with a gear drive for a performance option there is an easier way to get it to whine. You can hang a power steering pump on it and run Type F ****** fluid in it, that will make it whine especially if you let it get a little low. Another option is to run an alternator with an external static suppressor (like a Ford) then get a CB with a PA option and put your PA speaker under the hood, mount a cheap antenna near the alt and run your PA. When it winds up it will whine like a baby. Knew a kid in Wyandot County that had a mustang II with a 4 banger that his dad did this one. Fooled a lot of people. OK enough foolishness, a gear drive will effectively transfer harmonics to your valve train, and this can prove to be a problem in some applications so it is something to bear in mind.
Now let me chime in on this. My Roadster, 306 SBF, had a gear drive in it. 3 different times it broke. Once the bottom gear broke in 3 pieces at 70 mph = new motor. Once the large ildler cracked, no motor damage. lastly the large idler broke a tooth off at speed, No motor damage. Now the gear drive sits on the bench and it has a Cloyes true roller in it. I think it had something to do with harmonics. I drive the hell out of my Roadster and I think they do not like constant RPMs for long periods. I did like the noise and did not tire of it but now I can hear the radio at speed.
I love that sound too..almost like somethins' loose in the valvetrain, all that tickin' goin on, those in the know appreciate the solid lifter noise..
I have several buddies of mine that run gear drives...I have a 63 Dodge 330 Blown 871 Hemi and at least to my old ears the blower has a little more wine but to me the gear drive still sounds like a blower...
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