Timing Gears

**1989K1500** · 05-02-2005, 06:41 PM

Has anyone ever had timing gears? Have you had a good or bad experience? I Know a guy that supposedly shattered a set in his Tahoe after he had them a short time. The Hoe has a chip, but I dont think it has many other mods. Other people say that they wont shatter. Any input would be helpful.

**bobzilla75** · 05-02-2005, 07:18 PM

I am guessing you are talking about gear drive timing sets. With that assumption, they do not work with most computer controlled vehicles, including our TBI's. The gear drive makes a vibration or noise through the block that the knock sensor picks up as pinging, which pulls timing making it run like crap. If you are planning on replacing your timing set, may I recommend a good double roller set?

**1989K1500** · 05-02-2005, 07:28 PM

I didnt know trucks that old had knock sensors. 454ss has timing gears in his and says hes raced it and had no problem, but maybe his is okay because of reprogramming or something. thanks

**traviz71** · 05-03-2005, 09:08 AM

you can eliminate the knock sensor with a programmed chip but I haven't had any experience with the results of this. if someone has done so please speak up as I would also be interested in timing gears when i swap cams

**BossHogg 77** · 05-03-2005, 10:13 AM

Hopefully I can help you guys out here. I work for Cloyes Gear Co., and handle the Performance Products line. As for gear drives and computer controls, they generally don't work well together b/c of the knock sensor, as BobMS89shorty said. Also, gear drives don't just shatter. They require very careful installation and proper clearances to work, due to the floating idler assembly (the gears in between the cam & crank). If the proper clearances aren't established, the idler assembly isn't allowed to float freely which will cause something to break.

As for a double roller set, on many late(r) model TBI engines (usually 1990 and up), some grinding on the block behind the cam sprocket is required to clear a double roller set. If your engine is the original '89 model, you should be okay. I have a template I can fax you on where to grind if you end up needing it. We offer single roller sets that are just as strong as 'heavy duty' double rollers if you don't want to clearance your block. As for performance double rollers, there are really a lot of different sets to choose from. If you have any questions, just email me and I'll do my best to help you.

**airdeano** · 05-03-2005, 12:09 PM

boss,
i liked the crane billet single roller 11975-1 speed set that i believe is imported
from austrailia(?)... does cloyes offer a similar set. i suggest this model for
accuracy and less drag on the valvetrain.
i do prefer your chains as the o-ringed per link is dramatically superior and rigid
over other competitors.
one other thing, not to hijaak this thread....
why do installers of multiple keyway systems seem to mis-align the symbols.
the "■" or the "▲" seems to kick some major tail and cause mis-timing errors.
just an observation. last year i had 42 issues of improperly timed camshaft
installs. all late-model fuel injection systems with our harnesses.. teching
was tough.
airdeano

**BossHogg 77** · 05-03-2005, 02:05 PM

Yes, we have a set similar to the Crane (made by Rollmaster in Australia). For non-roller TBI engines, we have a set# C-3055 w/ single roller. We also have single rollers for the Vortec motors (both L31's and LS1's). As for the timing marks, the rectangle/square is for 4 degrees retard, the circle is straight up and the triangle is 4 degrees advance (all measured at the crank). Problem is, most people don't use a degree wheel and just think using the advance or retard key for more power (for either low end or top end) is okay, and there's where you run into trouble, esp. on computer controlled, EFI engines. All of our HP sets come with instructions on this, but you know what guys do with instructions...

**airdeano** · 05-03-2005, 09:01 PM

LOL... gawd...you mean "de"structions...
thanks for the information...
if you have those part numbers for the small block appz:
TBI c-3055
TPI
LT1
VORTEC
LS1
thanks again
airdeano

**Jimmy V** · 05-03-2005, 11:13 PM

i was told that to about gear drives but i have just recently put one in mine and it runs awsome infact never better... so i dontk now if that is jsut a mith or what but i gues i will find out

**BossHogg 77** · 05-04-2005, 08:23 AM

What year truck/engine are you running, Jimmy V? Glad to hear that gear drive is working (maybe I can start recommending them!).

Airdeano, here are the other part numbers you wanted. We have about 2 or 3 different sets available for each number you listed, some have our Hex-A-Just feature (which has an adjustable cam sprocket), and are designated by the A at the end of the p/n, the others are standard true rollers and have the 3 keyway crank sprocket. Thanks for letting me put these shameless part number plugs!!

Vortec: 9-3157 (Race True Roller), 9-1157 (Street True Roller)
TPI: 9-3145A, 9-3145
LT1: 9-9100 ('92-92), 9-3151 ('94-97)
LS1: 9-3153A, C-3210 (heavy duty single roller set)
7.4 Vortec truck: 9-3155A, 9-3155
8.1 Vortec truck: C-3217 ('01), C-3216 ('02-04)

**Jimmy V** · 05-05-2005, 10:53 AM

hey man its a 94 GMC 1500 4x4 350 5 spd..... i am running the pete jackson machined for noise gear drive its sounds exelent... i was told that i could not run a gear drive do to the knock senser and the timing factor but i took a leap and did it any way cause the way i think is that you never no for sure until you try it your self so i tried it and it worked great