Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
 Reply to this topicStart new topic
> How much do 901 gears weigh?, Cryo cost estimate...
bondo
post Mar 2 2005, 02:21 PM
Post #1


Practicing my perpendicular parking
****

Group: Members
Posts: 4,277
Joined: 19-April 03
From: Los Osos, CA
Member No.: 587
Region Association: Central California
I'm considering getting cryo treatment done on my 901 guts before I put it together. Jake said he pays $10 a pound. I'd do both shafts, 2nd through 5th gears, and the ring gear. Just wondering if anyone happens to know roughly how much that weighs.

User is offlineProfile CardPM
Go to the top of the page
+Quote Post
mattillac
post Mar 2 2005, 05:20 PM
Post #2


robots!
***

Group: Members
Posts: 536
Joined: 27-October 04
From: vallejo,ca
Member No.: 3,020
would the cryo treatment affect the measurements of the parts significantly?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bondo
post Mar 2 2005, 05:24 PM
Post #3


Practicing my perpendicular parking
****

Group: Members
Posts: 4,277
Joined: 19-April 03
From: Los Osos, CA
Member No.: 587
Region Association: Central California
As far as I know, no. It just ups the hardness and decreases wear. My knife is cryo treated, and I've done things with it that would break the tip off of any other knife I've ever used. Jake sold me on it after describing a bug trans that would repeatedly break until he cryo treated the gears.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
TravisNeff
post Mar 2 2005, 05:24 PM
Post #4


914 Guru
*****

Group: Members
Posts: 5,082
Joined: 20-March 03
From: Mesa, AZ
Member No.: 447
Region Association: Southwest Region
I dunno, but the gearbox weighs around 75lbs. You are stating that you want everything but the case (basically), I would wager a good 40lbs?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
mattillac
post Mar 2 2005, 05:28 PM
Post #5


robots!
***

Group: Members
Posts: 536
Joined: 27-October 04
From: vallejo,ca
Member No.: 3,020
does the treatment make the gears more brittle or anything like that. why no do the case too, as long as you're at it?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bondo
post Mar 2 2005, 05:50 PM
Post #6


Practicing my perpendicular parking
****

Group: Members
Posts: 4,277
Joined: 19-April 03
From: Los Osos, CA
Member No.: 587
Region Association: Central California
Not quite as simple as everything but the case. I won't do the inner diff, syncros, dog teeth, sliders, shift forks, reverse or output flanges.

I doubt doing the case would help in any way. The cryo process helps carbon steel change into a harder form. I don't think it will help al or magnesium, and I'm pretty sure even low carbon steel doesn't see a benefit. Its greatest benefit is for heat treated high carbon steel.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bondo
post Mar 2 2005, 05:52 PM
Post #7


Practicing my perpendicular parking
****

Group: Members
Posts: 4,277
Joined: 19-April 03
From: Los Osos, CA
Member No.: 587
Region Association: Central California
I'm not sure of the effect of brittleness, but I don't think that's the cause of failure in a 901.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Joe Bob
post Mar 2 2005, 06:03 PM
Post #8


Retired admin, banned a few times
***************

Group: Members
Posts: 17,427
Joined: 24-December 02
From: Boulder CO
Member No.: 5
Region Association: None
Every 901 that I have had let go was bearings...then they gears got all masticated....
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
mattillac
post Mar 2 2005, 06:19 PM
Post #9


robots!
***

Group: Members
Posts: 536
Joined: 27-October 04
From: vallejo,ca
Member No.: 3,020
so what parts are you planning on getting treated? just the main gears? input shaft?
could you treat bearings? hmmmmmm.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bondo
post Mar 2 2005, 07:23 PM
Post #10


Practicing my perpendicular parking
****

Group: Members
Posts: 4,277
Joined: 19-April 03
From: Los Osos, CA
Member No.: 587
Region Association: Central California
Well I've heard several theories on how they fail. One is that the shafts are able to flex out in the middle allowing 3rd and 4th to mesh incorrectly. Cryo treatment *may* prevent as much flex in the shafts. Another is simply too much torque on the pinion, causing its teeth to shear off. Then of course there's the bearing issue but I would think you'd get some noise from that before total failure. I'm most worried about the 3rd/4th failure because it would happen at speed, and possibly without warning. The last thing I want is trans lockup at 50 mph on a freeway onramp.

I'm also toying with the idea of a fluid cooling system, but I want to keep things simple. It would be nice to find a way to use the ring gear to pump the fluid through a cooler instead of having to add an electric pump. I'm told that just pointing the vent the wrong way will cause the ring gear to pump the fluid out, so if I design something specifically to do it it might work. Cooling the fluid will probably help bearing life.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Jake Raby
post Mar 2 2005, 07:28 PM
Post #11


Engine Surgeon
*****

Group: Members
Posts: 9,398
Joined: 31-August 03
From: Lost
Member No.: 1,095
Region Association: South East States
I REALLY believe in cryo!!! Every engine I build gets some degree of cryo work, and alot get every ferrous part treated.

I have personally seen parts only survive because of the cryo!

I even have all my tooling for the lathe and mill cryoed and have seen some end mills and turning tools last 4-5 times as long

I work really closely with www.percryo.com they are great guys that really have their profiles down to a science.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bondo
post Mar 2 2005, 07:52 PM
Post #12


Practicing my perpendicular parking
****

Group: Members
Posts: 4,277
Joined: 19-April 03
From: Los Osos, CA
Member No.: 587
Region Association: Central California
Cool I'll check them out. Doing the bearings is probably a good idea too. Renegade has some 901 "secrets" and I think cryo may be one of them.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Type 4
post Mar 2 2005, 11:22 PM
Post #13


Member
**

Group: Members
Posts: 412
Joined: 30-September 04
From: Costa Mesa Calif.
Member No.: 2,866
`Here is a list of companies
http://www.raceseek.com/coatings.htm
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
« Next Oldest · 914World Garage · Next Newest »
 

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 

Display Mode: Standard · Switch to: Linear+ · Switch to: Outline

Track this topic · Email this topic · Print this topic · Subscribe to this forum

- Lo-Fi Version Time is now: 13th July 2025 - 10:34 AM
Invision Power Board v9.1.4 © 2025  IPS, Inc.
All rights reserved 914World.com © since 2002
914World.com is the fastest growing online 914 community!
We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ...