Alternatives to Forged Internals
06-23-2004, 02:58 AM
#1
Alternatives to Forged Internals
I know there are other things you can do to engine internals to increase their strength. Has anyone thought about these as an alternative to buying new forged ones? Anyone know what sort of increases i strength we are talking about? Or costs?
Eg. Shot peening, nitrating, heat coatings, balancing, laser shock peening (do they use this for cars yet?) etc
Eg. Shot peening, nitrating, heat coatings, balancing, laser shock peening (do they use this for cars yet?) etc
06-23-2004, 03:26 AM
#2
Shot Peening:
Shot peening is a means of cold working the surface of metal parts by means of a hail or blast of round metal shot directed against the surface. It is equivalent to a myriad of small hammer blows impinged over the entire surface indenting the surface and causing plastic flow and work hardening of the surface metal. This work hardening of the surface metal increases its tensile strength and yield point and a small percentage of the beneficial results of shot peening are attributable to this effect. The greater benefit, by far, however, resutls from the fact that the surface metal is upset and put into compression; the surface compressive stress is extremely beneficial in obviating fatigue failures.
Carburization:
Carburization is the increase of the carbon content of (the surface of) a steel due to interactions with the environment at elevated temperatures.
Carbon has a large influence on the mechanical properties (hardness, strength) of the steel. Carburization therefore results in the formation of a very hard top layer that is more brittle than the material at the core.
Carburization toughens the rod's surface so that it resists crack formation. Carburizing allowed Honda engineers to reduce the cross section of the connecting rods, thereby reducing their weight (always a penalty in a reciprocating engine) by 25 percent, while increasing their strength by more than 50 percent.
Nitrating:
"Nitrating" is a process whereby the nitrogen from hydrous ammonia gas is forced to penetrate the surface of the steel by exposing the barrel to the ammonia gas for 40 hours or more while the barrel is at a temperature of about 965 degrees Farenhiet. There are advantages and disadvantages to Nitrating. One advantage is that under normal operations it will not rust because it will bore itself out. One the other hand, if it is not used daily corrosion will form quickly due to condensation.
Nitrating surface hardens the journals and makes them more wear resistant. Nitrating also slightly improves the fatigue strength.
Shot peening is a means of cold working the surface of metal parts by means of a hail or blast of round metal shot directed against the surface. It is equivalent to a myriad of small hammer blows impinged over the entire surface indenting the surface and causing plastic flow and work hardening of the surface metal. This work hardening of the surface metal increases its tensile strength and yield point and a small percentage of the beneficial results of shot peening are attributable to this effect. The greater benefit, by far, however, resutls from the fact that the surface metal is upset and put into compression; the surface compressive stress is extremely beneficial in obviating fatigue failures.
Carburization:
Carburization is the increase of the carbon content of (the surface of) a steel due to interactions with the environment at elevated temperatures.
Carbon has a large influence on the mechanical properties (hardness, strength) of the steel. Carburization therefore results in the formation of a very hard top layer that is more brittle than the material at the core.
Carburization toughens the rod's surface so that it resists crack formation. Carburizing allowed Honda engineers to reduce the cross section of the connecting rods, thereby reducing their weight (always a penalty in a reciprocating engine) by 25 percent, while increasing their strength by more than 50 percent.
Nitrating:
"Nitrating" is a process whereby the nitrogen from hydrous ammonia gas is forced to penetrate the surface of the steel by exposing the barrel to the ammonia gas for 40 hours or more while the barrel is at a temperature of about 965 degrees Farenhiet. There are advantages and disadvantages to Nitrating. One advantage is that under normal operations it will not rust because it will bore itself out. One the other hand, if it is not used daily corrosion will form quickly due to condensation.
Nitrating surface hardens the journals and makes them more wear resistant. Nitrating also slightly improves the fatigue strength.
Last edited by mchapman; 06-23-2004 at 03:34 AM.
06-23-2004, 03:42 AM
#3
Cryotreating:
http://www.diversifiedcryogenics.com/siezetheedge.htm
These guys tested 2 stock 440 snow mobile engines, one was treated with cryogenics. They leaned out the air/fuel mixture until the engines stalled. The non-treated engine detonated pretty easily and was damaged, and the cryotreated engine was left undamaged...
They have alot of info on this site. Check this pic with before and after 3500X image comparison. Looks like maggots to me!
http://www.diversifiedcryogenics.com/motorsports.htm
http://www.diversifiedcryogenics.com/siezetheedge.htm
These guys tested 2 stock 440 snow mobile engines, one was treated with cryogenics. They leaned out the air/fuel mixture until the engines stalled. The non-treated engine detonated pretty easily and was damaged, and the cryotreated engine was left undamaged...
They have alot of info on this site. Check this pic with before and after 3500X image comparison. Looks like maggots to me!
http://www.diversifiedcryogenics.com/motorsports.htm
06-23-2004, 05:38 PM
#4
Found this good write up of them doing a VQ30 motor with everything.
http://www.sportcompactcarweb.com/pr...scc_proj300zx/
They did the cryo treatment to their block and said this about it:
After verifying our block was thick enough to safely bore to 89mm, it was sent to Pacific Cryogenics to be cryogenically treated. Cryogenic treating is an extension of the heat treating process where the block is slowly cooled to near absolute zero (-320 degrees F) with liquid nitrogen and allowed to cold soak. The metal parts are then brought up to about 360 degrees (to temper the metal) and slowly chilled again. This is repeated three times or more during a 72 hour or longer total cycle.
Cyro treating completely stress relieves the block and actually strengthens it by increasing the amount of martensite (a hard crystalline variant of steel) carbide inclusions within the metal. It also rearranges the metal's molecular structure into a better symmetrical crystal matrix with more complete molecular bonds that further helps strengthen the block. These microscopic changes also increase abrasion resistance and the lubricity of sliding surfaces, thereby reducing friction. You can expect much longer wear of the cylinder bores as well as improved dimensional stability under all conditions. The improved dimensional stability improves head gasket and piston ring seal. Cryo-treated blocks can make up to 6 percent more power just due to better ring sealing and less internal friction alone.
In many ferrous metal applications, cryo treating can increase wear resistance by over 800 percent, fatigue strength by over 100 percent and tensile strength by up to 25 percent. The typical increase of wear resistance in cast iron like our block is 100 percent. As these improved attributes are all desirable things to increase in a high-performance engine, we are glad to take the time to do it. The price of cryo treating is relatively reasonable, yielding a good return for the money.
Although cyro treating is virtually unheard of in street car engine building, it is one of the secret tricks many top engine builders use to gain improved horsepower and reliability.
http://www.sportcompactcarweb.com/pr...scc_proj300zx/
They did the cryo treatment to their block and said this about it:
After verifying our block was thick enough to safely bore to 89mm, it was sent to Pacific Cryogenics to be cryogenically treated. Cryogenic treating is an extension of the heat treating process where the block is slowly cooled to near absolute zero (-320 degrees F) with liquid nitrogen and allowed to cold soak. The metal parts are then brought up to about 360 degrees (to temper the metal) and slowly chilled again. This is repeated three times or more during a 72 hour or longer total cycle.
Cyro treating completely stress relieves the block and actually strengthens it by increasing the amount of martensite (a hard crystalline variant of steel) carbide inclusions within the metal. It also rearranges the metal's molecular structure into a better symmetrical crystal matrix with more complete molecular bonds that further helps strengthen the block. These microscopic changes also increase abrasion resistance and the lubricity of sliding surfaces, thereby reducing friction. You can expect much longer wear of the cylinder bores as well as improved dimensional stability under all conditions. The improved dimensional stability improves head gasket and piston ring seal. Cryo-treated blocks can make up to 6 percent more power just due to better ring sealing and less internal friction alone.
In many ferrous metal applications, cryo treating can increase wear resistance by over 800 percent, fatigue strength by over 100 percent and tensile strength by up to 25 percent. The typical increase of wear resistance in cast iron like our block is 100 percent. As these improved attributes are all desirable things to increase in a high-performance engine, we are glad to take the time to do it. The price of cryo treating is relatively reasonable, yielding a good return for the money.
Although cyro treating is virtually unheard of in street car engine building, it is one of the secret tricks many top engine builders use to gain improved horsepower and reliability.
06-23-2004, 05:56 PM
#5
Same article but they mention the crank with the same treatment.
We sent our crankshaft to out to be cyro treated with our block. It is perhaps the crankshaft more than the block that can most benefit in the increase in wear resistance, lubricity and strength cryo treating can provide. It can improve the wear to the crank's bearing journals and also provide up to 100 percent more fatigue strength. Cryo treating also increases the tensile strength. All of these properties are highly desirable to improve on the crankshaft.
We sent our crankshaft to out to be cyro treated with our block. It is perhaps the crankshaft more than the block that can most benefit in the increase in wear resistance, lubricity and strength cryo treating can provide. It can improve the wear to the crank's bearing journals and also provide up to 100 percent more fatigue strength. Cryo treating also increases the tensile strength. All of these properties are highly desirable to improve on the crankshaft.
06-24-2004, 01:34 AM
#6
Registered User
Join Date: Nov 2002
Location: Sydney Australia
Posts: 1,934
Likes: 0
Received 0 Likes
on
0 Posts
Don't forget forged components are generally well balanced and light weight, not just strong. That said all these methods (with the possible exception of laser shock peening which I've never heard of or seen offered. Got a link?) are tried and tested.
06-24-2004, 02:01 AM
#7
Well i know our stock internals are already light weight and i know that Japanese engines of a few years ago were already extremely well balanced when compared to US domestic counterparts and I've assumed Nissan would have improved on this therefore the only part missing from the equation is the added strength.
If we can find out how much % stronger forged parts are we could compare that to the above processes then when I get prices, determine if any of the above is worth it $$ wise over buying new forged units.
Ive found a company in Melbourne which does shot peening and ive sent them an email to find out prices.
FYI, I think the Nitrating bit in the second post last paragraph is the same as the cryo treating. Nitrating must refer to the Liquid Nitrogen used in the process.
If we can find out how much % stronger forged parts are we could compare that to the above processes then when I get prices, determine if any of the above is worth it $$ wise over buying new forged units.
Ive found a company in Melbourne which does shot peening and ive sent them an email to find out prices.
FYI, I think the Nitrating bit in the second post last paragraph is the same as the cryo treating. Nitrating must refer to the Liquid Nitrogen used in the process.
Last edited by mchapman; 06-24-2004 at 02:04 AM.
Trending Topics
06-24-2004, 02:12 AM
#9
I found this on Aluminum,
http://www.metal-wear.com/racing.htm
"It is beneficial to treat both aluminum and cast iron blocks."
Thats just one site, im sure you could find more. I read earlier that alot of metals get benefits from the process.
http://www.metal-wear.com/racing.htm
"It is beneficial to treat both aluminum and cast iron blocks."
Thats just one site, im sure you could find more. I read earlier that alot of metals get benefits from the process.
06-24-2004, 02:20 AM
#10
This on Aluminum Blocks and Broken Conrods!
http://www.cryogenicsofindiana.com/racing.htm
BLOCKS: The treatment of the engine blocks should not only result in improved performance with less wear and breakage, but the stress relief and stabilization of the block should result in reduced distortion in other parts such as crankshafts and camshafts since they are no longer flexing and distorting. One instance with an aluminum Rodeck engine running in a winged sprint car during a season showed the engine blew five times, each suffering from a broken connecting rod. The next season using the same block only Cryogenic treated the owner notified us that after 31 races he had no engine part failures. The big difference now was increased performance which resulted in new chassis set-ups.
This site also lists all the parts you could Cryo and the benefits.
Or
http://www.cryoeng.com/images/MSCustomersSay.htm
"...we kept breaking rods" ( in a twelve head aluminum engine)... "We blew this motor 4 times in 18 laps on quarter mile tracks. "... I decided to get our aluminum Rodeck block treated, to see if it might help the engine live longer. With great surprise, we ran this same engine this year 30 RACES with no breakage. . . . We are very impressed with what just doing the block did for us that we are going to have both motors completely done from top to bottom. Keep up the good work..."
- Owner, Racing Co.
Are they the same story??
http://www.cryogenicsofindiana.com/racing.htm
BLOCKS: The treatment of the engine blocks should not only result in improved performance with less wear and breakage, but the stress relief and stabilization of the block should result in reduced distortion in other parts such as crankshafts and camshafts since they are no longer flexing and distorting. One instance with an aluminum Rodeck engine running in a winged sprint car during a season showed the engine blew five times, each suffering from a broken connecting rod. The next season using the same block only Cryogenic treated the owner notified us that after 31 races he had no engine part failures. The big difference now was increased performance which resulted in new chassis set-ups.
This site also lists all the parts you could Cryo and the benefits.
Or
http://www.cryoeng.com/images/MSCustomersSay.htm
"...we kept breaking rods" ( in a twelve head aluminum engine)... "We blew this motor 4 times in 18 laps on quarter mile tracks. "... I decided to get our aluminum Rodeck block treated, to see if it might help the engine live longer. With great surprise, we ran this same engine this year 30 RACES with no breakage. . . . We are very impressed with what just doing the block did for us that we are going to have both motors completely done from top to bottom. Keep up the good work..."
- Owner, Racing Co.
Are they the same story??
Last edited by mchapman; 06-24-2004 at 02:39 AM.
06-24-2004, 10:01 PM
#15
Based on a suggestion from gq we are going to assume that forged rods are at least twice as strong as the stock units. I think this is a fair guess based on the fact that the stock rods can handle ~500flyhp and the forged units should be able to handle at least ~1000flyhp.
Last edited by mchapman; 06-24-2004 at 10:25 PM.
06-24-2004, 10:33 PM
#16
This is just speculation / theory as there havnt been that many rod failures, but many have voiced this as a possible problem area. And I dont have any real world data to base these assuptions on.
Regarding our stock rods & shot peening or cyro treatment as an alternative to forged units due to price:
Providing the price is low enough and you get a ~30% increase in strength, then the benefit that I see is it would allow you to tune your turbo to a slightly higher level and drive it harder for longer without the worry of a major engine failure occuring through rod breakage.
i.e In theory you should be able to run you engine at least ~500fwhp or below with peace of mind. IMO 'peace of mind' is the missing element in turbo charging our engines. With a little headroom more for a bit more power.
Regarding our stock rods & shot peening or cyro treatment as an alternative to forged units due to price:
Providing the price is low enough and you get a ~30% increase in strength, then the benefit that I see is it would allow you to tune your turbo to a slightly higher level and drive it harder for longer without the worry of a major engine failure occuring through rod breakage.
i.e In theory you should be able to run you engine at least ~500fwhp or below with peace of mind. IMO 'peace of mind' is the missing element in turbo charging our engines. With a little headroom more for a bit more power.
Last edited by mchapman; 06-24-2004 at 10:43 PM.
06-24-2004, 11:16 PM
#18
Of course,
Well since you would be replacing the rod bolts at the same time you did any of the above work... You should be able to increase the revs past the current physical limits.
I think 7400rpm was the limit of the rods so you should be able to go a bit further, and if you had your pistons and/or your block done with cyro then the frictional forces would be reduced as well as increasing their ability to take the extra heat that comes with the extra engine speed with less chance of scoring the cylinders. Overall a id say its very suited for increasing revability.
Well since you would be replacing the rod bolts at the same time you did any of the above work... You should be able to increase the revs past the current physical limits.
I think 7400rpm was the limit of the rods so you should be able to go a bit further, and if you had your pistons and/or your block done with cyro then the frictional forces would be reduced as well as increasing their ability to take the extra heat that comes with the extra engine speed with less chance of scoring the cylinders. Overall a id say its very suited for increasing revability.
06-25-2004, 12:40 AM
#20
http://www.mrtrally.com.au/performance/testing.htm
Ive sent these guys an email as well. Note the % figures they are returning when you click on the Cyro or Shot Peen links at the top of the page.
Ive sent these guys an email as well. Note the % figures they are returning when you click on the Cyro or Shot Peen links at the top of the page.