3GTAs1TA1Z28

Will this combination allow me to pass emissions?

Guest

Those two have nothing to do with passing emissions.

3GTAs1TA1Z28

Geeh thats funny cuz if the Gear drive is detected by the knock sensor then it will adjust timing.....Or am I way out of the ball park here?

Stekman

I've seen mixed results - some say yes, some say no. I think it has a lot to do with the style drive used. I'm yet to see an actual knock count taken from an engine that runs a gear drive, though.

If the knock sensor is picking up vibrations from the gear drive, emissions would be the least of my concerns...

Dialed_In

iTrader: (3)

Use a good chain setup.

3GTAs1TA1Z28

I would assume anyone running a gear drive has a good reason.....Otherwise they would be running what came on the engine originally.....A CHAIN

Stekman

Then playing devils advocate: what would be your reason then?

3GTAs1TA1Z28

Come on now....

The logical and adult thing to say is they will never break a chain, jump time, they are virtually indestructable....


But the kid in me just says.......Man I Love That Sound...

Stekman

I have a chain on my 400 now and it's holding up just fine. If it can survive my 400, I am pretty sure it can survive your engine.

You probably won't break a good chain setup. If it skips, replace it. For the price of a good gear drive setup, you can buy a few good chain setups. Your reasons for wanting one are no different than everyone elses who as at one point wanted one. The logic just isn't there that I can see.

And from everyone I know in my area who has had one on their engines (a couple of chevy guys and a mustang guy), they all got sick of the sound it made within a year of buying theirs.

3GTAs1TA1Z28

well the way I look at it is when I get to be the age where I don't like the sound anymore its time to get a minivan.


And they have chains on 455 the size of the engine makes no difference.......a good gear drive will always outlast a good chain set

D's89IROCZ

I have a friend who lost 10 hp runnngi a gear drive in his stock car
I don't see why you want one other than sound . If you want the sound ...get a blower

3GTAs1TA1Z28

I'd rather finish setting up my turbo's

Dialed_In

iTrader: (3)

Most people get a gear drive b/c they want the sound and have no idea how they work or what they're used for besides "they spin the camshaft". Installing a gear drive for the "sound" is the wrong reason. A good aftermarket set wont skip or break if installed properly and if you measre for the right length it wont have much slop, if any.

3GTAs1TA1Z28

That holds true for anything though.......


Not that any of these great reasons or thoughts are helping but could we get back to what was asked..........

The reason behind the choice doesn't matter the quest for the anwser is....

Dialed_In

iTrader: (3)

PJ makes a quiet gear drive for FI motors that supposedly doesn't upset the knock sensor. But something tells me that a quiet gear drive will defeat the purpose of what you're trying to do.

3GTAs1TA1Z28

Pretty much well I will be going thru emission this week hopefully if I get my new Walbro fuel pump and the new Holley Adjustable Fuel Pressure Regulator Installed.

That is of course as soon as they get delivered.

CrazyHawaiian

Does anyone have any facts to prove a horsepower loss? Like dyno sheets or anything? I figgured there is the possibility you might loose a little bit of power like 1 or 2 hp but 10hp, thats alot.

Also curious if anyone into DIY tuning with scantools has tried this and what they saw. I read alot of what appears to be hearsay about the gear drive and knock sensors issue. Don't really see facts like knock counts comparing chain vs gear drive.

I have the Pete Jackson one, the noisy one. I bought it for a different motor build that was cancelled (Carb 350). I'm about to take the heads off the L98 in my 89 IROC-Z so I'm considering installing this gear drive while everything is apart. I know the chain in there now is stretched because I can see the timing moving around a little bit when I set it. So I can either use this part I already have or try to sell it and buy another chain. I have scantools so I would be able to monitor knock count and see if its a problem. I just dont know if I would be setting myself up for more work down the road. I dont really want to have to take it all apart again if it didnt work out. It would suck if it did cause alot of false knock and the EST system kills the timing. Especially since it was originally bought for the purpose of precise timing with the machined for noise part being the "why the hell not same price" train of thought.

88_Import_Slaye

Sound is what they advertise as the "cool" feature on the gear drives. I too will be getting on, when I do my turbo setup. I love the sound as well. Gear drives, on my 305? I must be doing it for the wrong reason too!

Please tell me what YOU think is the right reason, it sounds like he knew all the right reasons and the best one that got him was the "cool" feature of a great sound.

course, with no exhaust right now, I wouldnt be able to hear anything

BTW: CrazyHawaiian, I love the TG's in your sig pic. So hot.

D's89IROCZ

Sorry man , I don;t have the proof . It was just told to me by the guy who owned the car. I don't see why he would lie but I understand why you want to see a graph . I would too . I will try ands see if he has it laying around , as this was years ago for him on a car he hasn't had in ages

bowtienick

iTrader: (1)

i have heard of gear drives directing harmonics directly from the crank to the valvetrain, and vice versa. obviously this is not good. i can tell you firsthand it is easier to turn over a motor when you are building it with a chain vs a gear drive. i guess there is more drag, so you may lose a few horses.

Dialed_In

iTrader: (3)

Yeah, install a gear drive to be cool Let me know when you get that turbo project done.....I'm sure it'll be a monster

3GTAs1TA1Z28

I am sorry I do not see how have an idler gear would change how hard it is to crank over the engine......As a matter of fact I have 5 Third Gens hence my screen name and have built motors for 6....I have had chains on all of them and this is my first non Carb'd gear drive and turning over the engine is not the least bit affected by the gear or a chain....As a matter of fact this same engine that now is running a gear drive priorly had a chain.

88_Import_Slaye

non believer.

3GTAs1TA1Z28

Dialed_In

iTrader: (3)

What is there to not believe??? Your car has no turbo on it. Everyone has big plancs for their cars, most of which never happen. You can talk about it when it's done.

88_Import_Slaye

I agree, most ppl talk. However, you have no idea what I have in my "garage". I dont have the turbo in because I dont have one, and i'm still finishing things up to get the car drivable. I have parts to do the turbo exhaust (making my own), just no turbo yet. Tax season + 2 kids = $$$ for turbo.

My "big plans" were to own a camaro. Did that. Do a V6-V8 swap. Did that. So when I say my big plans next are for turbo setup, what leads you to believe I wont? I didnt have time, money or experience when I bought the car, nor when I started to gut my entire car and turn it into a rolling chasis. Took me two years to do the swap. Turbo will be no different.

Either way, gear drives are sweet and I dont see a valid reason to go with a dual timing chain setup vs gear drives, if the motor is in a state that you have a choice, such as my case where i'm rebuilding the "CAR", so I could have as easily gone with gear drive vs chain. If you rip apart your perfectly working daily driver to add gear drive, then that isnt wise.

But in the end, your car is your own and you can do what you want no matter what it is (this is a general statement, dont start a flame war).

3GTAs1TA1Z28

Look one thing at a time....First engine then turbo.....Have to crawl before I can walk.....I have the turbo...Just have gotten to the part were I can install it yet.....I to this car from a "sub frame and bare body to a complete car) in a matter of a couple months so give me a little time geesh....The one on the right is the one I will be installing the one on the left is a TO4B just to use as a reference point.

Guest

Lots of conjecture, as usual. Typical gear drive post. I wish people that responded actually had some firsthand experience first.

I dont have any false knock, never did. And its a PJ "Quiet" gear drive though its anything but quiet.

D's89IROCZ

I just said , a guy lost power with one . Thats all .

Ricktpi

I have the PJ quiet also. Can't really hear it over my exhaust though. Bought it because the Cloyes dual roller setup would not fit properly on my late model roller block & the new GMPP one had too much slop for my liking.

Grim Reaper

The knock sensor works on harmonics. The only way ANY engine noise can affect the knock sensor is if the noise corresponds to the harmonics of the knock sensor. If the noise does not match the harmonics, the knock sensor could care less.

And, SHOULD the knock sensor actually detect it, then you just do a little prom tuning to filter out that noise. If you want a gear drive - do it. And, should you decide later you don't like it, replace it. It's not a big job.

Most people who own a particular car that they are modifying will often replace a number of parts over the time they have owned the car. One friend changed his cam 4 times before he finally found the one he wanted - a nice solid roller.

Part of life is "living and learning". It's your car and your labor to do the swap. Do what makes you happy. I think "modifying by popularity contests" is a poor way to modify an engine unless you have never done it before and need some suggestions. But, they are only suggestions. You are the decision maker.

3GTAs1TA1Z28

This is what I am talking about.....Thank you....

Coach Hawk

I'd bet that the guy who lost 10 HP with a gear drive actually did loose 10 HP because of the gear drive. However, I doubt it's because of the gear drive setup, but more from the cam timing being off slightly with the new drive. That's why you should always degree your cams whenever your doing a performance oriented cam or timing set swap.

88_Import_Slaye

Good tip

D's89IROCZ

Now , thats a likely possibility .


In the end , I am gonna put one on my 85 Monte winter beater for the sound . It is pretty cewl.

shawnc16

Just some info......the gear drive unit doesnt last longer than a chain drive.......for some better info the hellical cut gears that last longer than straight cut gears are quiet.....

you seemed a bit cocky at the beginning of the post.....thats not a good way to get some help

3GTAs1TA1Z28

If I seemed cocky at the beginning of this post is because I ask a question and my first response was they have nothing to do with each other.........HELLO.... They have everything to do with each other if the Gear drive gives off harmonics that the knock sensor pics up....I did not know if the knock sensor pics up certain harmonics (like the ones from a gear drive) Hence the reason for this post.....But if you do not know the anwer, dont throw in your 2 cents just to post.


Not trying to rag on anyone but seriously I have asked a question and you know what....I still have not gotten an answer to it....I have heard alot of people say to get a chain, get a chain, get a chain. But it would seem no one has gone thru emissions with a gear drive and or no one knows if they can

Coach Hawk

If the gear drive does not cause false knock, then the computer will not pull timing, so your emissions will not change. Because each brand of gear drive is different, and each engine runs a bit differently due to many factors including what gas you use, wear you bought it, how hot it is outside and a zillion other factors, the only way to be cetrain is to datalog the car before and after the swap and see if the knock readings have changed. If they stay the same, it's not causing false knock and won't be a problem. If they do change, you may have issues. You could also "cheat" during the test by disconnecting the wite going to the knock sensor so it will sense no knock whatsoever, real or otherwise.

3GTAs1TA1Z28

ok first of all thank you...
Second of all I dont not have datalogging equipment....
Thirdly I am not about to pull the Gear drive to re-intall the chain or i would go thru emissions with the chain then swap back again...
And Fourth wouldn't disconnecting the knock sensor throw a code?

shawnc16

Pretty sure it wont set a code.

Coach Hawk

Basically, it's kinda like this. Unlike some of the other sensors, the computer is not aware of the status of the knock sensor so it won't know it's missing. Because it's a 1 wire sensor, all the computer knows is if it gets a signal from this wire, it pulls timing. Disconnect the wire, no signal. It's not like a TPS or MAP sensor where the computer will realize it's missing and throw a code.

3GTAs1TA1Z28

Good to know......I will have to try that...But if the knock sensor is detecting other knock (not from the gear drive) but other knock it won't do its job then I still might not go thru Emissions Correct?

shawnc16

the knock sensor shouldnt be sensing knock.....its only there as a protection device for detonation or anything else that would "knock"

3GTAs1TA1Z28

I am sorry I am confused by that. A knock sensor that doesn't detect knock?

shawnc16

Yur knock sensor is useless unless theres something wrong with your engine......does your engine suffer from detonation?

3GTAs1TA1Z28

The knock sensor detects Harmonics (detonation) but if the gear drive is producing the same harmonics or even similar harmonics as detonation it could think that it is detonation not knowing the difference....I understand it won't pick up a knock (like a spun bearing or what have you) but the harmonics which gear drives definately produce.... What I am trying to figure out is if those harmonics will be seen by the knock sensor.

shawnc16

thats where you need a scan tool.....or an o-scope.....which i doubt you have those tools readily available.

3GTAs1TA1Z28

that is exactly the reason for this post to see if anyone has dealt with this before or know the answer......

shawnc16

sorry bro Michigan doesnt have emissions testing so i donno what to tell ya

Guest

If you are that worried about it setting off your knock sensor (highly unlikely) and retarding your timing (likely doing you an emissions favor anyway), then you should not use it.