Is this a matching gear set?
 

I'm looking at a replacement set for 2nd gear for my 915.

Trying to ascertain if this is indeed a matching gearset. Both gears appear to have the same manufacturer stamp "73 H X *" but only 1 has the handscribed number "9972".

The smaller gear does not have this number scribed on that I can see.
I'm inexperienced with trannies so any advice is appreciated.

http://forums.pelicanparts.com/uploa...1568494764.JPG
http://forums.pelicanparts.com/uploa...1568494764.JPG
http://forums.pelicanparts.com/uploa...1568494764.JPG

9 73 should be year of manufacture. HX should be the gear ratio. The acid etched numbers are the individual S/N. They usually match the hand etched.

Yes, so without the hand etched numbers on the smaller gear, there is no way to tell if they are indeed matching?

That fixed gear looks kind of hammered. I would keep shopping. 1973 is the first year of a 14 year manufacturing run. I’d be looking for a gear made in the 80s.

And no, we can’t tell if they are matched but most likely they are.

thanks Matt.

It is a matching gear set.

It sounds like you have had some problems-- I think you should consider buying new gears. I can recommend the Guard Transmission gears. I have been using them for nearly 20 years.

HX is a very common 2nd gear ratio used in nearly all the 915 5-speed transmissions. You shouldn't have a hard time finding a decent used pair if that's the route you'd like to go.

I got a very nice HX from Mike Bruns. He may still have a few pairs on hand and i'm sure they're in good shape.

http://forums.pelicanparts.com/porsche-911-used-parts-sale-wanted/981240-915-gears.html

Gonna agree with Matt here. The chips at the end of the teeth in the first photo are certainly not a good sign. Little hard to be sure from the photo, but the tooth surface condition in the third photo (same part) looks dodgy -- could be the photo tho.

As KTL has indicated, there are likely plenty of used HX gear sets around. If that one is not suitable for your application I am happy to suggest several resources that may have a better set.

For example, Partsheaven here in Norcal might have an Hx set or perhaps a few-- I hear they are liquidating everything. Good friends about 20 minutes from where I live.

Be ware that likely many dismantlers like them have not been able to buy as many 911 cars as a decade or so ago... so you may have to call around.

As we discussed via e-mail, I doubt your 915 situation is a worn out 2nd gear, but I am no expert. Perhaps folks here can recommend someone near your location that can help you get your issues sorted quickly.

Again, there is NO question that is a set-- I am pretty sure I got it used from WEVO-- they sold it to me as kind of a favor years ago. Whether it is better or worse than what you already have is hard (perhaps impossible) to assess by e-mail.

Sometimes the etching can be hard to see, especially on an old gearset that’s been around the block a few times. I had to use good light and a magnifying g glass to make out the etched numbers on a 901 gearset once. Maybe a moot point in this case