Just curious about pros and cons of installing a gear drive in place of a normal timing chain. What I understand is that they prevent the movement of cm timing, because they don't have a chain to stretch. Usually their description is accompanied by "minor machining may be required." What is this machining? Do they cost hp or have no noticebale affect on it? What about noise? Are they worth the trouble? Let me know what you guys think.

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82 Camaro:
350, Erson cam, ported heads, Crane Hi-6 ignition, Accel supercoil, Comp Cams 1.6:1 rocker arms, Turbo 350 tranny with 2500 stall.

 

I know that the gear drives are far superior to the regular timing chain sets, but I couldn't use a gear drive timing set on my car because it will screw up your knock sensor and make your car run extremely poor. My suggestion would be to just get a good Comp Cams or a Cloytes double roller timing chain.

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End

Current Mods: LT4 Hot Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

7.5" 10 Bolt with 3.42s soon to come!

 

But he can on his.

Being an 82 it's carbed and IIRC not computerized so there is no knock sensor. Out of all of the cons, not one of them outweighs the pros of a geardrive. You get more accurate timing, no chance of breaking a chain and less wear on the block. The only con I can see in your application is more noise, of course you might like the noise so that would be a pro right?

Don't know about the "Minor machining" part though, sorry.

 

I was also thinking of buying a geardrive for my 88Iroc but like Dan said, CompCams and Edelbrock suggests not to use in computer controlled cars regarding the knock sensor. I wonder if there is a way around this? Anybody know?

 

Yea, there is a way. You ignore the 'experts' and install it anyway like I did. I have a PJ 'quiet' gear drive and no false knock.... ever.

'Minor machining' consists of following the supplied directions and maybe having to do some trimming to parts to get the proper clearance between the idler gears and the timing cover or engine block. Ive installed 2 of these so far and didnt have to do any 'minor machining.'

 

I second this. Madmax and I have been fighting this topic on this board for years. I had the PJ Quiet Gear Drive installed in my 1987 IROC-Z almost three years ago. I have never detected false knock with my Auto Xray. My track results? Just look at my signature.



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Willie

Supercharged 1987 305 IROC-Z, Daily-Driver, Emissions-Legal.
Paxton (6-psig): 12.57 @ 111 mph.
Paxton (6-psig) & 50-hp nitrous: 12.04 @ 114 mph.
ATI D1SC (10-psig): ?

http://willie.camaro-firebird.org/

1987 "20th Anniversary Commemorative Edition" Z28 Convertible -- Super Chevy Show Class Winner, 1998.

 

I have an 84 corvette with a peter jackson gear drive it has been in the car for 3 years and I have had no problems with the knock sensor or anything else.The one thing I am a bit worried about [because it has happened to me before] is if you go on a long trip like 1000km's or so is vibration.
The result in my case was cam breaking in three places.Hope this helps.

JEFF

 

I am running a Pete Jackson quite gear drive also. I have been using it for a while now and no know problems... I have never run any diagnostics to tell if I get any false knock, but doubt it highly. I am also still running the stock computer chip made for the 305..... I say use one, they sound great, won't stretch, and won't ever jump around and screw up timing.

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1991 Camaro ,polished TPI, 355ci. Sportsman 11 heads, LT-4 Hot cam,Pete Jackson gear drive, on,and on, and on... 13.6 @ 102.5 with a 2:73 open rear, no traction, no tuning, no practice. Car is pictured in Chevy High Performance magazine, June 2000 issue.
http://www.geocities.com/jasonsz28us/INDEX.htm


1985 California Edition IROC red, polished TPI and polished wheels, otherwise completely stock 305ci. 700r4

1991 fullsize Blazer 4-wheel drive, 350,700r4, Pro Comp lift, K&N, TBI spacer, 3" Catco cat, 3" cat back Flowmaster, etc....

1997 GMC Yukon, red, 4 wheel drive, leather, loaded, Gibson exhaust, K&N intake, Boston pro series speakers..... That's it so far.

1971 GMC Jimmy, green, 4 wheel drive, project vehicle..

Time to sell a vehicle or two 8^)

 

Okay.,, Here goes...

I have had a Pete Jackson gear drive on my car since '97 when I graduated Wyo-Tech in their Hot Rod class... We put the gears on and we did not have any problems with the computer.

And I still do not to this day... No false knocks... no nothing... No breakage of cam or bad valvetrain parts.....

To bad this rumor of false knocks got started.... I have yet to meet one person that has encounted that problem..... Only the stories from their friends friends brothers uncles cousin name Hill Billy Bob....

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Sportsman II 72 CC heads, Pete Jackson gear drive, Performance Resources chip, Edelbrock 1 5/8" headers and Edelbrock cat back exhaust, hi-flow cats, Trans-go stage 3 shift kit, Vigilante 9.5" 2800 stall convertor, SLP cold air induction, SLP roller camshaft, 24lb ADS injectors, AFPR, 3.45 rear end gears, and other goodies...


raven

 

no probs with a pete jackson timing gear at all i love the way they dont stretch like the double roller. just a little FYI though get the quiet if you wanna be legal and have an everyday driver cuz if you just wanna **** everyone off get the noisy version like i have i love it so much sounds really cool but can be rather loud and annoyoing to say the least once you go gear you never go back.