I asked about aluminum cryo tempering, they say that even though its not a ferrous metal, it still has strengthening and wear resistan effects. hmmmm......mabe both heat and cryo will do the trick.

Forsure getting it done to the valves though. I had a squeaking when I got the engine, every revolution of the crank. When it was on normal timing it would only fire 3 cylinders. Did a compression test and #2 cylinder had 0 compression. Took the head off and the exhaust valve in the #2 had a hole burnt right past the valve seat. Heat and cryo treating must make this problem never happen again.

By Parker (24.98.213.4) on Monday, March 29, 2004 - 11:50 am:

well, im not sure if cryo hardening of a cam is going to help any, as honda already case hardens their cams. if you are wearing through the hardening then there is a problem. if you wanted to, you could try an "oil squirter" of sorts tapped from an oil passage to the #4 lobe to help with oiling...

By Jacob (67.171.196.144) on Monday, March 29, 2004 - 10:17 am:

It's obviously an oiling problem. But my City Turbo engine's not worth enough to me to redesign the head for proper oiling of the #4 CVCC lobe (as this is an inherent problem with City Turbo's). While it's apart I will see if there is a location where an extra oil passage could be added, but I figured why not try all angles...

By Bryan (66.32.102.128) on Monday, March 29, 2004 - 06:38 am:

Careful though, cams are made of cast iron, not steel. I am not sure that you could have it nitrided. If the city turbo engines are only having trouble with the #4 lobe, then it might be an oiling issue rather than a hardness issue. A cvcc lobe has hardly any pressure on it. The valve springs can be pushed by open by hand. I would try and direct a spray of oil to that lobe.

By Jacob (65.113.241.30) on Thursday, March 25, 2004 - 01:54 pm:

Now that's a good explanation. I didn't feel like breaking out the old Material Science book to figure out the metal states. Thanks, I'll likely check into that carbonitriding process for my cam.

By Evan (12.111.166.96) on Thursday, March 25, 2004 - 11:50 am:

Don't waste your money having aluminum parts cryo treated, the process is only effective on ferrous alloys. It works by transforming retained austenite into martensite. Austenite and martensite are molecular structures which only exist in ferrous alloys (iron and steel).

Cryo treatment is most effective on heat treated parts with high alloy additions. Parts such as valve springs, connecting rods, and transaxle gears respond well to cryo treatment. High strength bolts, such as connecting rod bolts, may also repsond well to cryo treatment.

Cryo treatment is less effective on parts which haven't been heat treated, low alloy steels such as mild steel, or thin sections (under 1/8" thickness). If you have all three conditions then don't bother with cryo treatment, it won't do anything useful. For example, a mild steel bracket made of 16 gauge (.062") and not heat treated would be a waste of money to cryo treat.

Camshafts which experience excessive lobe wear are probably not good candidates for cryo treatment. Camshafts are usually only case hardened, not through hardened (this is especially true for OEM cams). The case depth is typically only .010" to .030" thick, so there's very little chance of retained austenite. If you're experiencing problems with excessive lobe wear your money would be better spent on a carbonitriding process. This is a combination of carburizing (adding carbon to the surface of the steel) and nitriding (adding nitrogen to the surface of the steel). It's a case hardening process which is much more effective than either carburizing or nitriding alone for protecting high wear surfaces.

Your local heat treatment shop can help you determine the best processing to give you the performance you want at the lowest cost. It's more expensive than cryo treatment but it's also more effective. You can save money by getting a bunch of cams together and having them treated all at once. Heat treatment shops run these parts in batches, so it usually costs as much to treat one part as it does to treat a whole furnace load of parts.

If you have trouble finding a heat treating shop which can help you, send me an e-mail.

By Jonathan (66.252.173.251) on Wednesday, March 24, 2004 - 10:46 am:

From my understanding, current superconductors are 100% efficent, but the energy required to keep them cold enough to operate properly is still high enough to keep them from everyday use.

By Parker (24.98.213.4) on Wednesday, March 24, 2004 - 10:34 am:

are current superconductors 100% efficient though? i thought that they were nearly that, but werent able to reach 100% efficiency until absolute zero.

By Jonathan (66.252.173.251) on Wednesday, March 24, 2004 - 09:28 am:

And here are a few links from google....

http://www.efunda.com/processes/heat_treat/matl_modify/cryogenic.cfm

http://www.onecryo.com/onecryo/how.htm

Looks like I shoulda googled first, posted second

By Jonathan (66.252.173.251) on Wednesday, March 24, 2004 - 09:25 am:

Jacob, I think absolute zero was derived from measuring the amount of total energy contained in an object at different temperatures, and plotting on a graph the values. That graph was then extrapolated down to where there would be zero energy, but when everything gets down to near zero, wierd things happen, and even negative temperatures (below 0 K) are thought to be possible. Something that'll give you a headache thinking about it here: http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/neg_temperature.html

The whole zero electrical resistance thing is possible well above absolute zero, I think they've gotten superconductors up to about -150F or so, and there's current research on room temperature superconductors.

But back on topic... I wonder if this will be any better than surface hardening, or if the two processes can be done on the same part. The way the cryogenic process works, I think, is that the deep freezing removes all the imperfections in the crystalline structure of the steel.

By Jacob (65.113.241.30) on Wednesday, March 24, 2004 - 09:08 am:

Absolute zero is zero Kelvin, or -273.15 Celcius. Absolute zero has never been reached, it is a calculated value based upon an equation I'm sure I had to derive at some point.

It is believed that if we could reach absolute zero, we would be capable of transmitting electricity without any sort of losses. i.e. in an environment with no electrical resistance, this would make electrical transmission 100% efficient.

Cryo treatment isn't a god-sent. It's along the lines of polishing your rods to remove stress-risers.

Thought it was funny that you put prices up for things that people wouldn't generally do. What's it cost to do some rods/crank/flywheel?

People with City Turbo engines that keep rounding off CVCC lobe #4 may want to consider this for their cam....

By Parker (24.98.213.4) on Tuesday, March 23, 2004 - 10:04 pm:

what it does is convert all the steel/iron to a more stable, stronger form of steel, im not sure what its called, but i have done research on cryo-treating for brake parts.


www.praisedynobrake.com read around they have pretty cool info there.

and yes, absolute zero is -273C

By Jonathan (68.193.10.141) on Tuesday, March 23, 2004 - 05:57 pm:

Not to nitpick, but that's still a long way away from absolute zero. I think absolute zero is -461 Farenheight, -273 Celcius. I'm sure that it'll do something to the structure of the molecules, but I'm not sure what. In all the properties of materials classes I had in college, the only phase changes we went through with iron/steel stuff was after it got rather hot, but the teacher always said the properties remained the same once it cooled down enough. We didn't really cover the super low temperature phase changes, though. Looks promising, but I'd want to do a little more research before I send something off to them.

By farenheight101 (24.69.255.203) on Tuesday, March 23, 2004 - 03:55 pm:

Hey guys,

Is there anyone in the middle of an engine rebuild right now or soon? I read an atricle in Turbo and High-tech Performance about cryogenic tempuring. They have a big chamber where your parts are placed. This chamber is connected to liquid nitrogen tanks. They convert liquid nitrogen to a gas form and fill the chamber with it lowering your parts core tempurature to -300 fahrenheit. This is supposed to stop the molecules from moving (If I remember correctly from school its called "Absolute Zero") and make them pack together, making the metal alot more dense. This makes the metal more resistant to cracks, warpage, and stress points. This tractor puller went from blowing its turbo every 6 pulls to every 140 pulls or something, what a difference!!

Its cheap too!!! I e-mailed them and the prices are as follows:

"Hi Colin,

Thanks for you email and interest in our process. We process parts on Tuesday's and Friday's week in and week out. If we receive parts by 1:00pm on Tuesday they will be processed and shipped out on Friday. If we get parts in by 1:00pm Friday they will be processed and shipped out the following Tueday.

Here is a break down of the cost for your 4 cylinder engine.

Head $ 127.50
Valves $ 2.25ea
Valve Springs $ 2.25ea
Camshaft $ 25.00

Or the complete engine for $450.00

If you have any other questions please don't hesitate to call.

Best Regards,

Rob Jenkins
Industrial Sales Manager
300 Below Inc.
(800)550-2796
www.300below.com"

What do you guys think? I think its a breakthrough unknown about!!! You know how many races you could win just because you can push your engine that much harder!