Billet cams

[dalewrc30]

As many of you may know, the 51 is prone to snapping the cast iron cams,including the Moriwaki and HRC, when heavier springs are used and its not advisable to continue with the std springs with extra lift.

I have been receiving a steady series of enquiries regarding the billet cams I had made,so have decided that there may be enough interest to get another batch made.

Cams have 11.4mm lift vs 10.4 stock , 274* duration vs 251* stock.Profile is very similar to stage 2 Moriwaki.
Also have the HRC grind with 13.00mm lift,probably too much for anything but a full race engine.

The cams work well in a street engine,not cammy at all, with excellent power all the way from around 4,000 to redline.
Please dont ask for dyno figures etc as I've never had my engine on the dyno and I did pistons and headwork at the same time. I can say that engine was definitely as strong as my 05 Ducati 999R with a full exhaust system.

The cams are excellent quality. Made from EN39B steel,ground,case hardened to a depth of 1mm then finish ground to the highest standards. Cost will be US$1650 plus postage ( around $65)
In order to help keep costs down I need the stock cams as p/exchange as I remove the stock gears and have a jig for setting them at whatever lobe centre is required on the new cams.

If anyone is interested,please feel free to pm me or email with any questions.I will require a 50% deposit but will only need that if there is enough interest to.

Dale

[irishaggression]

oh god. this is the last thing i needed to read

[Redstar]

So what kind of octane should be run with these cams, high comp pistons, airbox and exhaust?
How many people do you need to be able to make this happen?

[Smokngun]

Interested...YES, able to purchase...no However if you need a test mule, I would be proud to distribute them here in the states for a free set!

[dstewart]

Here is a photo of the above mentioned cams.

Dale is good to his word and his cams are very high quality. The one week link to the RC's motor is the cast cams. If you EVER want to build a motor start here! Billet cams for the RC are hard to come by but when they do jump on them!

[dstewart]

Originally Posted by Redstar

So what kind of octane should be run with these cams, high comp pistons, airbox and exhaust?
How many people do you need to be able to make this happen?

You may be able to get away with 91. The trick is to keep the cylinder head temp down to help prevent detonation. In the summer you may need 100OC UL Pump or equivalent. The higher duration cams wont require any higher OC then the stock cams, actually they would help prevent detonation. The higher overlap will bleed off cylinder pressure at lower RPM's. Its the hight comp pistons that will cause the engine to require a higher OC.

[desmo11]

Hmmm, I'm not familiar with EN39B. How does EN39B differ from EN40B (or it's .mil equivalent 722M24)?

When you say .040" case hardening I assume you mean case depth (50 HRC?)? Therefore case hardening is carburizing or possibly carbo-nitriding?

Have you considered EN40B and nitriding? Another alternative would be A2 tool steel. I have a friend making cams out of that now.

Can you do custom grinds?

[dalewrc30]

I'm not a metals expert but my toolmaker buddy,Dave, has almost 50 years experience and he regards it as the best low carbon steel for this application.
The case depth is achieved through an extended treatment,done at this countrys major heat treatment company, and we have measured it at 1mm,hardness is around 64 Rockwell.

I asked about nitriding to try and reduce cost,only one grinding sequence instead of two, however my buddy is not keen on it.Even though hardness of around 70 Rockwell is achieved,the actual depth is measured in microns.If you were to lose even .001" it will be through the hardening.

He would prefer to make something that is bulletproof rather than risk having a failure due to having a piece of debris go through the oil system.If these cams were to suffer damage to their contact surfaces,they could easily be reground.

Dave has thousands of masters available ,the beauty of bucket and shim is theres no rocker ratio involved so theres probably something to match whatever was required.
I've chosen the Cosworth profile as its similar to the Moriwaki stage 2 and has slightly smoother acceleration figures according to Daves CamPro and is a good allround profile.

Dale

[irishaggression]

I'm in on this. who else is coming with me.

[Rothmans]

I am asking some people who do not frequent this forum....

[dalewrc30]

Originally Posted by desmo11

Hmmm, I'm not familiar with EN39B. How does EN39B differ from EN40B (or it's .mil equivalent 722M24)?

When you say .040" case hardening I assume you mean case depth (50 HRC?)? Therefore case hardening is carburizing or possibly carbo-nitriding?

Have you considered EN40B and nitriding? Another alternative would be A2 tool steel. I have a friend making cams out of that now.

Can you do custom grinds?

Ok, I've gotten my book out and en39B (English designation) is equivalent to
AISI 9310
BS835 M15
JIS G4102
SNCM815

Hardness: 64 Rockwell Core Strength 1300MPa
Carburised at 880-930*
Annealed at 820-860*C

So,excellent toughness,hardness and case depth.Nitriding is way down at 550*C? Way less core strength.

Dale

[dalewrc30]

Originally Posted by irishaggression

I'm in on this. who else is coming with me.

Hey Irish,will get back to Dave and seen what kind of timeframe to get them done.Thanks,

Dale

[desmo11]

Ah. AISI9310 / AMS6265 (AMS from memory).

That material carburized makes sense. Your case depth does too, but I'm afraid you're very, very optimistic on the hardness values. It's probably more like HRC ~60 (max), effective case depth is HFC~50. That is more than enough to do the job though (your material spec is good). Is your friend using an actual Rockwell tester, or are those numbers converted from Vickers harndness or something?

As for EN40B or nitrided cams I have to disagree with you there. Commonly cams are nitrided to .004-.008" depth and work just peachy in many applications (including F1). They are flat out as tough as nails. The advantage to nitriding is less deformation. Your core hardness is HRC mid to low 40's on either carburized or nitrided so no difference there. Just get rid of the white layer from nitriding.

I'm more accustmed to nitriding and would go for that myself, but sounds like your 9310 spec is compatible with the RC's buckets so I'd stick to it. 9310 is a nice gear steel.

[dalewrc30]

[quote=desmo11;498680]Ah. AISI9310 / AMS6265 (AMS from memory).

I'm afraid you're very, very optimistic on the hardness values. It's probably more like HRC ~60 (max),

As for EN40B or nitrided cams I have to disagree with you there. Commonly cams are nitrided to .004-.008" depth and work just peachy in many applications (including F1). They are flat out as tough as nails. The advantage to nitriding is less deformation. Your core hardness is HRC mid to low 40's on either carburized or nitrided so no difference there. Just get rid of the white layer from nitriding.

Hi Desmo,

the hardness figure is from the catalogue supplied by my steel merchant.Up to 64,so probably in the low 60s.
Dave does cams for a guy who supplies Triumph twin cams to the US.They are nitrided,however he had to take a lick off a set recently ,less than .002",and it pretty much went through the hardening and they could be filed!
He was told by the heat treatment company that although the hardening does penetrate to the kind of depth you have indicated,it drops off very quickly from the surface,so much so that the hardness tester they use,requires a different(much gentler) application to measure hardness.

As for core strength,as I understand it,a metal treated at 880*C then quenched will retain pretty much all of its Toughness whereas a metal nitrided at 550*C will suffer a substantial drop off.

Again,I dont hold myself to be an expert on these things,this is just what I've been told by the guys I trust.

I'd have no problem nitriding them myself,but the last thing I want is guys buying these and suffering a failure some time or ruining a set of cams because another part failed and they weren't able to repair them.With a .040 case depth,its probably going to have full hardness for at least .030".

If anyone wants to go down the nitriding route,theres going to be a saving.After having a closer look into this,the cost of case hardened sets will be more like US$1500 delivered.
Nitrided sets will be US$1200 delivered.

Dale

[dalewrc30]

Originally Posted by dstewart

Here is a photo of the above mentioned cams.

Dale is good to his word and his cams are very high quality. The one week link to the RC's motor is the cast cams. If you EVER want to build a motor start here! Billet cams for the RC are hard to come by but when they do jump on them!

Thanks for the kind words Damon.

[mrgrn]

a free bump for Dale

[irishaggression]

Originally Posted by dstewart

Here is a photo of the above mentioned cams.

Dale is good to his word and his cams are very high quality. The one week link to the RC's motor is the cast cams. If you EVER want to build a motor start here! Billet cams for the RC are hard to come by but when they do jump on them!

so do we need to get the hrc spring kit as well to go with the new cams?
dale pm me your payment information.

[thorsten]

To locate/fab Springs and retainers maybe to biggest prob.
Powerful Cams are already under development from my side/Josh.
For full benefit you need to be able to rev up to ~ 11300 rpm.

Reg the Cams/Philosophy:
If it would only depend on me I would have done very good Cams long Time ago, but it takes a while to find a good manufacturer.

At least I have got a perfect Cam Profile, but works only in conjunction with HRC Springs ( or copys, because they are no longer available ) and HRC retainers, or similar ones, which should weight not more than ..(hope I remember correctly ??) 9gr.

[irishaggression]

Originally Posted by thorsten

To locate/fab Springs and retainers maybe to biggest prob.
Powerful Cams are already under development from my side/Josh.
For full benefit you need to be able to rev up to ~ 11300 rpm.

Reg the Cams/Philosophy:
If it would only depend on me I would have done very good Cams long Time ago, but it takes a while to find a good manufacturer.

At least I have got a perfect Cam Profile, but works only in conjunction with HRC Springs ( or copys, because they are no longer available ) and HRC retainers, or similar ones, which should weight not more than ..(hope I remember correctly ??) 9gr.

thorsten whats the specs on your cam profile?
with dales cam profile should i get hrc springs and retainers?

[irishaggression]

beuller??