Twin cam head for the L6 from Derek at Datsunworks

[johnc]

Happy birthday Tony.

 

http://en.wikipedia.org/wiki/Battle_of_Sunda_Strait

[LanceVance]

Happy birthday Tony.

 

http://en.wikipedia.org/wiki/Battle_of_Sunda_Strait

 

Happy Birthday Tony! here is a little gag gift:

 

[Tony D]

Sun Tsu's fleet is delivering my manifold, someone will find it and like Gavin Menzies, and will write a book about it's discovery!

 

 

Yup, hear the stories of the survivors of Sunda Straight, of the last Marine at the highest position on the ship refusing to abandon ship and giving the Japs hell to the bitter end...

To think that ship accounted for most of the American interments at Kanchanaburi is humbling.

 

It's one thing to read about it, to see the photos.

 

It's another thing totally to ride the rails, see the bridge, the cemetery, and know the history...

 

I digress...

[Derek]

Thought I'd do a quick update.

The cam situation is a lot tougher than I led myself to believe. Actually it's not tough at all it's just expensive:) Custom made steel billet cams are going to be in the neighborhood of $1300.00 - $1800.00 EACH! And this does not include the final grind. 

 

I'm working on a much saner approach using cast iron cores which is what most of the cam cores are made up of. Google "chilled iron cam cores" and you'll learn plenty. The manufacture of these cores are not at all outside the bounds of what I can do. Being a cast item it actually brings it into my sphere of influence. I have 2 foundries that can pour the cores depending on what iron needs to be poured.

 

The general consensus of my "brain trust" is that Ron Iskenderian is the guy to talk to as he is receptive to this kind of crazy talk. He is on vacation for two weeks so unless he's following this thread it will probably be three or more weeks before I can get some answers. So we're basically on hold for a bit.

 

I also revisited why I ultimately chose the K20 over the RB head. The RB head is a lot trickier to machine and cast. It has an internal oil passage that needs to be cored as well as 2 passages that need to be gun drilled the length of the head. They are too small to core as the sand would probably break. Plus there is the matter of machining the cam towers and precision boring the lifter bores. If we were doing a group buy of 10 or 15 heads and getting all the machining done at one time then this would be feasible.

 

Of course if we were doing a group buy of 10 or 15 cam core sets the price would probably come down on those as well.

 

So it goes.

Derek

Edited October 3, 2014 by Derek

[Tony D]

I still think billet cut cams with hard facing is doable... I know that is how they were done to great effect in the early 90's.

[G-E]

Nitriding is not expensive, I sent 6 vg cams in for nitriding and came to around $25/ea...

 

For the better grades like 4140, nitriding is excellent, but for the 10** series steels, you'd be better off induction hardening.

[Tony D]

I think that's the key---cast is cast...low grade and soft requiring a hardening process.

 

Using a higher grade rod billet and chucking it in a CNC. lathe would allow the rough shape to be done, a little finish grind on the journals then off to cam grinder (soft) for cam profiling and nitriding.

 

I think that would do it, and allow rough work to be done in-house to some extent.

 

Or cut lobes and journals and use tubular cam cores like on Enterprise IMO. And White Superior engines. Keep the core, replace lobes and journals at overhaul time. Nitrogen, hot oil bath, and some woodruff keys!

[Derek]

It's most likely the machining of the 40 mm round down to the profile that is the majority of the cost. Not the hardening. If I was doing it I would do all the round work in the lathe and then switch over to the mill with a 4th axis to cut the lobes. I can do this but I can make more money doing what I do best and pay someone who does cam cores all the time. And that costs between $1300.00 and $1800.00 each. 

 

My inbox hasn't exactly been overflowing with people who want to buy a head. And the cam prices haven't made it any better.

 

Let's face it. When we were all saying I wish there was a bolt on cross flow twin cam head for the L6 we should have added "and it needs to be under $5000.00 complete with cams valves etc". Because based on the feed back I've received off forum this is the point where the decision is easy. After that for every $1000.00 you add it becomes harder and harder. The $3000-$4000 "just for cams" pretty much killed off the two that were serious.

 

If I pull the plug now at least I'll shut everyone up about a twin cam head for the L6 and the mods can instigate a immediate ban on anyone who mentions it again:)

 

Because a twin cam head for the S30 can't be produced in the numbers that will be purchased by S30 owners for under $8000.00. And that's if you're creative and can scrounge. $10,000.00 or more if you don't want to scrounge and would like to make reasonable power.

 

Even if I based it on an RB30 the additional machining costs would put it on par with the K20.

 

There is a reason the OS Giken is $40,000. This kind of work is expensive.

 

4 or 5 people who are ready to commit at these price points and it can move forward if not I've accomplished what I set out to do which is to showcase 3D sand printing to my clients. And believe me at this point they're impressed.

 

Derek

[V-Fib]

This may sound silly/outlandish but how about a crowd funding campaign to garner a much larger audience, fund initial R&D/prototyping and in turn offset the cost of each final unit?

 

I am pretty sure that by reaching out to people in said manner would probably be on a more national/global scale. Given that OS Giken is sold out before they start a production run I'm sure a unit for a fraction of the cost would get people's attention.

 

I fall into the category of interest but don't have 8K burning a hole in my pocket. If it was in the less realistic realm of $3-5 then mere mortals such as myself would be more interested.

 

Just my opinion.

[Dan_Austin]

I've been trying to figure out the small parts list to finish the head.  I was surprised to

see new stock exhaust rockers are more than a performance set.  Based on that, if

one of the Honda specialists could be persuaded to put together a 6 cylinder kit it

looks like another $2k for the valve train, not counting the cams. 

 

The price ends up higher than I hoped and lower than I feared. I'm still interested,

but it has slide into the realm of selling other toys to justify the purchase to

She-who-controls-the-retirement-accounts. 

 

Keep the updates coming, some of us fence sitters may not need much of a push...

 

Oh, and I suspect this might go over real well with Z owners in Japan.  My experience

with the Japanese is that they will pay top dollar with no haggling IF the finished

product is a known quality.  That may bump the volume enough for the frugal

crowd in the U.S.

Edited October 4, 2014 by Dan_Austin

[rturbo 930]

I feel like the European/Japanese/Australian market would be more willing to spend the money on a head like this, since Zs seem to more expensive/rare in those parts. American Z owners are cheap.

 

That said, I think $10k is still pretty cheap for such a custom piece.

[Derek]

Hi Dan

Not sure what performance or what stock your looking at but the stock honda exhaust rockers are $25.00 each. Being a non vtech you use exhaust on both the intake and exhaust. PN 14624-RAA-A00.

Ferrea roller rockers are around $80.00 each.

 

Derek

[Derek]

 

 

That said, I think $10k is still pretty cheap for such a custom piece.

 

I'll just put you down for two then

Edited October 4, 2014 by Derek

[Dan_Austin]

Clearly my lack of Honda knowledge was biting me.  That trims the cost a bit.

Hopefully a chat with Ron Iskenderian can help trim it a bit more

 

I have a feeling that once you have a full parts list/cost and a running 'prototype' the orders

will follow.  I am a mouse fart away from listing my beloved RZ500 to send money your

way... 

[G-E]

Derek, starting with a bar of 4140HT (pre-hard) would be a decent place to start with cam cores, easy enough to machine at high speeds since it's about RC30...

 

You can start by making basic blanks, leave oversized lobes, just focus on the main journals, and any small-ID locations between things, then send it off to Isky to do their magic -- I wonder how close to the factory K20 profile you'd end up staying, I imagine it would work, but you'd need to figure out what the engine likes ultimately.

 

I wouldn't worry about the heat treating at this point, use it as a proof-of-concept cam, you can easily run the engine with it for testing, keep the rpm below 4k -- just show a running engine?

[Tony D]

^^^^^ this is exactly my thought... Don't cut the lobes except round. At RC 30-40 they can be ground easily enough.

Ron cuts cams for $100 each if you're manufacturing (at least L-Series) and the stagger is the same it's just setting up the machine.

 

It's the rough blanks. If you got bearing journals, and round cam lobes (like the old Nissan Billets) you're ready to go to the specialist grinder.

 

I think even replicating the stock cam profile would produce startling results in an L-Series Conversion.

 

 

The vast majority of S30 owners aren't frugal, they're CHEAP. Period. As John Coffey said "One paycheck away from selling their car to make rent!"

 

This never was more than a niche buy part. OS Gikken sold 12 in their first run back in the 80's. I know three owners of that head, ridden in one of them when new, the other two bought used heads complete and are building their vehicles now.

 

They paid significantly more than what our proposed finished cost would be... As likely would I for a whiz-bang part nobody else in the world had...

 

I don't know that I'd scrap it...just not commercially produce it! There are those willing to see it through. Me? I'm having a beyotch of a time finding my contact email for the cam blank sources from the 90's! I know. A guy who was cutting billet blanks for Hondas in the 90's for a SoCal Cam Supplier. I KNOW he wasn't selling them for $1,000 each, and I KNOW the finished cams were not sold for significantly different prices than later "core exchange" cams that were from cast billets.

[Xnke]

4140 isn't what I had luck with for that...

 

Cast cores with hardfacing didn't last. Been there, 4130, 4340, neither. They don't have the durability, didn't hold up for me.

 

I went with 8620 deep-cased after a "pre-grind", followed up with a final grind, and that so far has lived. I doubt that this is going to be required, though, I was spinning a 0.620" lift 310* seat duration, 280* duration at 0.200" lift roller profile. Springs are a smidge stiff in that N42 head...you won't take them out without specific tools.

 

How are the Honda cores made? Maybe remelt and cast from those? They'll have the proper metallurgy, and you have an example to harden to spec.

 

G-E, an unhardened cam will NOT live at all in the roller environment. It will begin to break down VERY fast.

 

Derek, Look at the hardness of the cam followers and go within 6RC, but no closer than 3RC on the hardness.

Edited October 5, 2014 by Xnke

[1vicissitude]

I don't have the money at this time for a head like this, so what I am saying is purely conjecture at this point, but I have the feeling if one were built, running and making good power the orders would come.

 

It is not uncommon for modified k24s to be making 350-400whp N/A these days, honestly it's just a matter of a port job and a combination of the right parts. There's no wizardry in it, anyone with a credit card can copy and paste one of the many known combinations. At the end of the day a $8,000-10,000 is surely expensive, however if these heads are 400whp capable and proven it puts them in direct competition with most swaps both in terms of power and cost. I bet you'd find there are more customers than you would first like to think. I mean even a basic LS or RB swap costs similar.

Edited October 5, 2014 by 1vicissitude

[Tony D]

This is the typical S30 project...everybody is "interested" until it's announced that it's not free, we aren't paying you to take them off our hands, or they don't get their car featured in a magazine for installing it.

 

As I said, the LY Head was quoted at €35,000 for reproduction, and they needed one core to dissect (¥3,500,000-BARE) in order to make the cores and set it up... Then you gotta make valve train.

 

This projects R&D to first raw casting isn't close to the $76,000 proposition WITH cams! The valve train is easily available.

 

I said from the outset there were three components than needed to be sourced: head, rockershafts, and cams.

 

Give me a second to work on those billet cam blanks. I may have to make a phone call in the middle of the night, but I know for sure I know someone who has done this before!

 

Screw the rest of those guys out there who "WANNA"! I'll do it because I'm the deviant with the head nobody else in the world has because I know which had fills up first.

 

And I'm not a "Service Engineer", I'm a "Service Intestine"---I make shit happen!

 

And that hand ALWAYS fills up first compared to "WANNA"!!!

[Tony D]

Xnke, you are right on roller metallurgy, JeffP knows this from his days at Sig Erson

 

Trust me when I say, one way or another a roller cam has been in the works for an L-Series based on Malvern Racings work for some time. The metallurgy is set, it is known. That has been worked out.... Were you running a set of Malvern Roller Rockers? If so JeffP may want to talk with you about that aspect of the L-Head work...we were looking at a split cam tower to allow an unrestricted lift compared to the journal towers currently in the L-Head.

 

It's just getting the billets with journals done that is the stumbling point right now, and I think I know where to solve that...it's just contacting the guy when I'm on the other side of the planet!

Edited October 5, 2014 by Tony D