[track73]

I used a Cam Correct timing system on a stock car engine I built back in 2003. Cam Correct was designed to control variable valve timing. . Basic kit includes a tracking shoe, a spring loaded shoe, drill fixture, hardware and sealer. Drilling and tapping of block required. It must have worked in conjunction with the other parts used. The car had 5 of the top ten qualifying times. Too bad the driver wasn't up to the motor.

[Formulajones]

Originally Posted by track73

I used a Cam Correct timing system on a stock car engine I built back in 2003. Cam Correct was designed to control variable valve timing. . Basic kit includes a tracking shoe, a spring loaded shoe, drill fixture, hardware and sealer. Drilling and tapping of block required. It must have worked in conjunction with the other parts used. The car had 5 of the top ten qualifying times. Too bad the driver wasn't up to the motor.

That sounds pretty cool.

[Poncho60]

Anyone have a picture of an intact NYLON cam gear that they could post? Thx in advance for any inputs.

[Goatracer1]

I always liked to run the Tempest 4 cylinder timing chain but you can't find real ones any more.

[shaker455]

Originally Posted by Poncho60

Anyone have a picture of an intact NYLON cam gear that they could post? Thx in advance for any inputs.

I might once I pull off my fuel pump and look in there!

[Bill Hanlon]

Cheap, probably too cheap, but interesting.
https://www.ebay.com/itm/PRW-0145502...AAAOSwT2BcEqM~

[shaker455]

Haha!
I think I have a Pete Jackson here!

[ponyakr]

" Anyone have a picture of an intact NYLON cam gear that they could post? Thx in advance for any inputs."


There's a pic of a nylon teeth gear about halfway down the page, at this link. I assume it is a Pontiac gear. Not sure. Mine had one, but I don't remember exactly what it looked like. Saw it around 48 years ago.

https://www.pontiacdiy.com/rebuild-p...y-parts-guide/

[Old Goat Racer]

GM-NOS 4 CYL. TIMING CHAINS. 9772801 I sold Tom V. one about a year ago.
The rest are NOT for sale.

[shaker455]

Thanks not looking to buy one.

[t money]

I had and sold one of the cam gear a year ago. Light weight. Also a little story. When in high school my first timing chain was on the family 77 Chevy Impala 305 with a nylon gear with 175,000 miles.

[dataway]

My first Pontiac ... a 66 Tempest went 90,000+ with a nylon gear. I still say the problem was engines that ran too hot and turned the teeth brittle with heat.

[shaker455]

Very likely, look at the size radiator they had @ the time.

[Chief of the 60's]

Originally Posted by dataway

My first Pontiac ... a 66 Tempest went 90,000+ with a nylon gear. I still say the problem was engines that ran too hot and turned the teeth brittle with heat.

You were the original owner?

[Formulajones]

My father bought his 69 GTO new, still owns it. When it had 40k miles on it a friend of his at the dealer told him to bring the car in and he would get a timing chain done on it while it was still under warranty (5year-50).

Interesting to think about, that even in 1969 this was obviously a known issue and his buddy took care of it while under warranty.

I have all kinds of these nylon cam gear stories from my own personal experience with various brands of engines. Most of which aren't good, lol.

[Cliff R]

It's simply one of those concepts that was good on paper but worked poorly in actual use, sort of like the "odd-ball" 1975 automotive Quadrajets. It looked good on paper adding in an APT system to bring fuel in under the main jets, and they even added an auxiliary power piston to some models. It made a brief one year model run then they moved on and up to a superior design that raises the power piston using tapered primary metering rods.

A plastic timing set link-plate design would last just about forever IF the plastic didn't get hard/brittle and break into pieces from constant heat cycling.

One of my mentors WAY back when I first got into this hobby campaigned a very successful 67 Camaro in Super Stock and used the same Speed Pro 3/4" wide link plate set with a plastic top gear over and over and over on each engine he prepared for that car. It looked "mint" every time it was removed for inspection. He claimed that it picked up the car just a tad providing constant tooth contact and absorbed some of the harmonics created between the crank and camshaft. This was evident when I helped him set the timing as the timing mark was ROCK solid clear across the RPM range unlike many I've followed since then using other methods to drive the camshaft.

Even with all the potentially good things that could come out of using one I opted for the 3/4" wide sets with the heat treated steel gears instead, and to date they have been 100 percent successful. The only timing set failure I had was with a much more expensive (and popular) Rollmaster, but even that said lasted nearly 10 years and that engine was being raced couple of times a week and the car driven as much as I could find time for it.......Cliff

[Formulajones]

It's been mentioned to me from a couple of engine builders I respect that Avon makes an excellent timing set. Sounded funny to me at first. When I hear Avon I think of makeup. Different company, lol.

Apparently they've been in the timing chain business since 1972 and now go by the name of Pro Gear. They offer various versions depending on what you want and seem to be reasonably priced. I'm told that in use they have been excellent, even on blower/drag race applications. Been wanting to try one. Some brands of engines they offer different roller and chain setups depending on the type of camshaft used (flat tappet vs roller)

They talk about heat treated gears and other features in their descriptions.

http://www.progearweb.com/index.htm

[shaker455]

Neat! thanks for the info and link.
Reason I posted is I have a newly acquired 67' GP with 73k on the ticker and nothing looks like it's ever been apart.
I started thinking if it ever had a timing chain service and if that year was produced with the nylon stuff that I've seen fail over the decades....
It is a year with that feature so I'll be taking the fuel pump off to see what's up in there!

[GRX]

Originally Posted by Sirrotica

For whatever reason the olds, buick, and chevy counterparts seemed to be able to keep nylon toothed gears a bunch more miles than Pontiac did before they went toothless. I've seen Pontiacs bad at 30,000 miles and every once in awhile they'd make it over 60,000, not usually though. I've seen chevy especially, make it near 100,000 miles before they failed.

Originally Posted by Half-Inch Stud

Pontiacs ate the nylon Timng gear quickest because Pontiacs made a ton more torque, from a bunch more stroke then those other GM engines. The instantaneous torques ran the Timing chain ragged.

Originally Posted by android 211

Cadillac used them too. Their valve spring pressure was very low. Maybe the gears didn't have to work as hard.

DING ... DING ... DING .... Johnny, tell him what he's won.

Increased tension from Pontiac's factory double valve springs is the answer.

And since we are talking Animal House .... Ramming Speed !!

[shaker455]

Originally Posted by Cliff R

It's simply one of those concepts that was good on paper but worked poorly in actual use, sort of like the "odd-ball" 1975 automotive Quadrajets.........Cliff

SEND ALL YOUR 75' QJETS HERE!
Same casting & easy fix if you want to run yours!