What GM engines share the same distributor gear as the GMC 228, 248, 270, 302 series of motors? I have an HEI that is prepared for the GMC engine and I am running a steel cam. I see that my options are a steel gear or a bronze gear and I see a lot of aftermarket bronze gears with 13 teeth and 1/2" shafts that say they are for chevy small and big blocks.

Would one of these V8 gears work on my GMC 270?

Here is some info that may help you decide which gear you need.

Hi Greg - I actually have that same bulletin and was hoping to find a modern distributor gear that would match.

I have a billet steel cam coming and have been told by the cam grinder that the alloy would require a bronze gear. I have found a number of distributor gears that are shown to work with the 230/250/292 family of motors and I have also heard that these motors have the same kind of gear as the earlier GMC motors . . . if someone can confirm this, I'll spring for a Bronze gear for the later L6 and use it in my GMC engine.

Thanks,

Ken

People have converted the old 6 distributers for use in the newer 6s. There is some difference in how deep they sit in the block but I think the gears are the same. The new 6 and small block use the same gear.

Tom Landon I believe has the bronze gears that he sells as an option for his HEI distibutors that are converted to be used in stovebolts. http://www.stoveboltengineco.com

I have a 292 under the stairwell in the garage - I'll pull the dizzy out and compare to the older GMC and see how things look. If it looks the same, I can check gear mesh with the cam and see how it looks.

thanks for the confirmation that the later sixes and the sbc use the same gear.

Ken

I use a Mallory bronze gear (can't seem to find the #) The key is oiling it. The cam and crank spinning should be plenty but I feed oil to it. The original engines bypass filter fed back into the crankcase tru a fitting right by the distributer. I now feed a direct line to that fitting hole. I feed it from a tee which comes from the front of the block at the cam and goes to the rocker arm shaft thru the head. I use a Parker stainless fitting filling it with solder and drilling a .045 hole at an angle aiming at the gear. This has stopped all wearing of cam and dist gears on my racing GMC. I can send a picture if you like....Good Luck

JD - thanks for the description. I have several of the funky T-Fittings that screw into the oil gallery on the front of the block and can feed the head / rockers with one port and the distributor gear with the other port.

If you happen to run across that Mallory Bronze Gear # - that might save me a wrong guess. The distributor that I am planning on using has a 0.491 diameter shaft.