anyone happen to know or ever had one tested?

 

S.O.S lol ..info needed

 

subscribed for possible results.

 

I am assuming you mean with the nitride surface treatment intact.

 

that is the problem here, if you do a good test and not a superficial test, you are going to destroy the bearing surface.

I have tested many honda parts on my rockwell hardness tester. I have not tested a crank but I can take a guess what is is going to read. My guess is 42 on the rockwell scale.



Why are you asking, if you don't me asking

 

Assuming they are all made equal, you can find used cranks on eBay for $100-$150 shipped if you want to destroy one (I found a few f22 and h23 cranks after a quick search)...

 

Bump foot info

 

im actually concerned with the snout rather than the journals

im curious to know what range oem falls into and what range would be acceptable for a snout made of 4340

from the info I have found, raw untreated 4340 tends to average 25

 

my logic behind my guess is because Honda probably used the same hardness material on the bottom end bearings as they did on the top end (head).

Before heat treatment readings do not really matter. As long as you can get it to be around 40-59 rockwell scale you will be fine, in my opinion of course.

The type of material also does not always relate to the hardness because some material is also hard at the surface, other is hard through out.

We modify the snout on s2000 cranks for them to be used on kseries engines and we never had to worry about the hardness. Getting the right hardness reading can be a challenge because you need high dollar equipment and it needs to be calibrated correctly and it has to be sitting straight as possible.

 

in other words you feel using an untreated 4340 cromoly snout with Rockwell of 25 would be risky for an n/a drag application?

 

If you send me a piece I could test for hardness and chemical. Let me know.

 

if it was not for snout, my answer would be 100% don't do it.

But its hard for us to assume what kind of forces are involved with the snout. MY guess is, its going to be just fine because all it needs to do is lock the movement of the crank pulley relative to the crank.

Instead of worrying too much about the hardness of the metal, i would probably focus more on the size of the crank key that would be used in the snout because you want to use a piece of metal that will have no play at all and be as tight at it can get, because if the machining of the snout is not as good as it can be, I am guessing that's where the metal will show its weakness by getting banged every time the crank key slightly moves. So maybe tell the machine shop to slightly undersize it for it to fit just right , instead of just making the snout just what a normal snout should be to fit a regular crank key.

The slightest amount of "play" could eventually hurt you but I the reason for hardness of 40 on the honda bearing surfaces its obviously because they are going to get way more abused than a crank key. Good luck!

 

I'm sure someone has a destroyed crank to test

 

I agree they are probably around 40rc just from experience machining all sorts of metals at varying hardness. Any harder and than that and the cranks could potentially shatter, they need that hard surface but soft on the inside for toughness.

Modding an S2000 crank only requires removing material correct? I would be much less worried about doing that than I would be about what Randy is trying to do.

If this piece is to be welded on I would probably stick with the 4340, if it is attached by some other means I might consider doing something tougher like a P20 or A2 tool steel. Welding dissimiliar steels, especially when one is hardened or case hardened worries me.

 

it will be bolted on using left hand thread then welded in place. my main concern is obviously the keyway/timing gear. another concern would be the portion of the snout which drives the oil pump.

Rosko, did you machine a similar setup from aluminum?

 

I built a new timing gear out of tool steel that incorporated a hub in which I could attach an aluminum crank pulley. This way I did not need to extend the crank or worry about the keyway. I will try and dig up a picture later on today. Tons of dyno time on the setup and many passes last season and no issues with either the hub or aluminum crank pulley *knocks on wood!

With what you are doing I would machine the keyway last, after its welded, or else you are going to have a hard time getting that timed out correctly to line up when the threads are tightened.

I see it going like this:

Machine stub piece for snout, slightly oversize
Machine threads in crank, install
Weld to crank
Turn stub "true and concentric" to existing snout
Machine keyway full length of stub

The oil pump drive is pretty easy, theres a step/shoulder on the crank that needs to be turned off, then you can make a sleeve with the flats on it to press on afterwards. I made the sleeve out of tool steel (A2 to be exact) and then heat treated it and drew it back to 50rc. I put about a .0005" press fit on it, put a good bit of heat to it and let it slid right on. Its not keyed in any way and I dont feel it needs to be. The press fit alone should be enough to hold it in place as well as being sandwhiched when the pulley bolt is tightened. The clearance between the flats and the oil pump gear is actually a lot. For whatever reason I always assumed those two pieces were a fairly tight fit, but they are extremely sloppy from the factory.

 

hmm that all sounds good except the part about the aluminum pulley lol

yes I agree the keyway should be cut last to make sure its placed properly.

the gearator drive does have plenty of play I have noticed in the past, im beginning to think I should have the snout nitrided.

only problem is I don't want to nitride the whole crankshaft and lose the oem journal spec and bearing clearance. I also don't want to have the journals ground pre-nitride, I just don't want to open that can of worms.

I guess the snout could be nitride before being installed/welded, it would be a pita to cut the keyway after nitride though id imagine.

the machinist is saying the nitride will bring it to Rockwell 60, im also concerned that may be a bit too hard...

 

what are your thoughts on the H series oil pump gearator drive which is machined into the snout. do you feel 25 would be too soft there or would it be worth giving a try to find out?

as for the keyway, I can have it made as tight as possible im sure. maybe a semi-permanent press fit keyway

 

This particular pulley probably isnt as crazy looking as you are thinking, the weight of the setup is in the hub piece, theres really not much to the pulley itself. No issues so far and I dont really expect there to be.

Another way I thought to do it, and I believe I ran this by Cody, was to use an ATI damper, and build my own hub with timing gear incorporated like I've already done. The ATI pulleys come apart, its a hub and a dampening ring so I think that would be easy to do. If I ever get some free time I will look into that setup more. I'd love to be able to run the setup with as little crank work as possible.

 

Keep in mind the front main seal will also be riding on this piece, I would make it harder just for that reason. Also this piece will provide a shoulder for the crank timing gear and pulley to stack up against. A harder piece will maintain the integrity of that surface.

 

And as soon as you can manage that you better get in contact with me. I am staying with this motor I have for now until all of this gets sorted out. I know some body out west has been doing this work motors already and it ran for awhile. Just cant remember who.

 

QSD did it and I believe they were the first. There was also a guy from Texas who welded a piece onto the end of the crank. I'm not sure but I believe both of those are still up and running as well as mine of course. All 3 of us took a different approach.

 

hey shawn can you shoot me a pm here or email at mcody014@gmail.com thanks

 

What happened with their idea of using an H/F crank as a doner and cutting the snout off and threading it?

 

good thought Shawn, glad you pointed this out.

as for the aluminum pulley, its not the weight that would worry me. its the harmonics dampening or lack there of