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Derek

Twin cam head for the L6 from Derek at Datsunworks

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VCT cam cores are finished. Really happy to have this behind me. I had one set of S7 blanks so there was no room for error.

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Cross drilling VCT control circuit. Talk about butt clenching. Sounds a little crispy as the drill bit breaks through the other side. S7 tool steel is some pretty tough stuff.

 

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Finished VCT circuit. Still have to deburr the holes.

 

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Here is a video of the finish pass ending on lobe 6 and starting on lobe 2. I finish them in the firing order so I don't get confused. The noise in the background are 2 other machines that I'm coding and running at the same time so I try and keep things simple:)

 

 

Next they'r off to Crane for heat treating and OD grinding.

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Santa was late but better late than never:)

 

Went down to the foundry and pored the remaining 4 heads right before the holiday break. Went down and picked them up a couple days ago. Next stop Ohio for hot isostatic pressing.

 

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I can't wait to be able to get one of these for myself! Hopefully, you'll still be selling after I'm finished with school. Do you have any more information on how your first customer's build went? A build sheet accompanied by a dyno sheet would be pretty great. 

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7 hours ago, alexx933 said:

I can't wait to be able to get one of these for myself! Hopefully, you'll still be selling after I'm finished with school. Do you have any more information on how your first customer's build went? A build sheet accompanied by a dyno sheet would be pretty great. 

Well I hope to be making them for a good long time:)

 

HP specs are based on estimations by Rebello since there are currently no running heads. V2 hasn't even been assembled yet since he decided to retire, build a custom house and shop and put a twin cam head on his Z car all at the same time. Hopefully that will be moving along soon. V3 is moving forward but slowly since it is only a small part of a comprehensive engine/car build.

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32 minutes ago, alexx933 said:

It sounds like this guy needs to have V2 and all the parts taken off his hands as he sounds quite distracted... I'm sure somebody around here would be willing to help him out haha

 

Probably not going to happen:) Actually V2 is a one of a kind head. V3 and V4 are virtually identical except for some adjustments to gating and wall thicknesses. V2 in visually different and totally unique. He also ended up with 2 valve covers and three timing covers since they only fit that head:)

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4 hours ago, Oblithian said:

Given that you need custom manifolds it seems unusual that you would opt for a tower with MPI rather than DI. Either way, I am certain a few hundred people would be interested in buying this, myself included.

 

Hi.

I don't know what tower with MPI refers to. I mean I probably do but not by that name.

 

I hope demand is still there when I actually have heads to sell. No mater either way as long as I have one:)

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11 hours ago, Derek said:

I hope demand is still there when I actually have heads to sell. No mater either way as long as I have one:)

 

Speaking for myself, I have money set aside and I've been lurking this thread waiting for news of public availability. I'm sure I'm not the only one. :)

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Got the valve covers done.

 

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They are machined and somewhat finished. I've decided that since I don't know what people plan to do for finishing that I would leave the final cleanup to them or their powder coater.         I sanded down all of the sand tears, Rand a DA over most of it and then ran them in the vibratory finisher.

 

The flange is grooved for a .125" o-ring. I also machine in clearance for the cam towers and bolts.

 

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There are 2 bosses on either side of the plug hole. This is for a KN20 COP. The bosses are positioned so that you can have the plug facing forward or backwards. It's up to the end user to drill and tap accordingly. 

 

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Semi action shot.

 

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Derek,

Is the valve cover O-Ring Groove square or trapezoid?


Our gearboxes use a trapezoid cut o-ring groove on the splitline. We can do that easily because the cutter can enter from multiple points around it...you would have to plunge in and go...
That trapezoid holds that O-Ring in place so you really don't have to glue it except around 25mm at each endpoint where oil can enter from the gearbox. I would assume with this one you could either superglue the O-Ring stock and then put it in place or maybe butt the ends and apply a dab of Loctite 598 / Permatex Ultrablack to seal the oil intrusion point.

It makes it kind of nice as you lift the cover off and the O-Ring is held fast and doesn't fall all over stuff.

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3 hours ago, Tony D said:

Derek,

Is the valve cover O-Ring Groove square or trapezoid?


Our gearboxes use a trapezoid cut o-ring groove on the splitline. We can do that easily because the cutter can enter from multiple points around it...you would have to plunge in and go...
That trapezoid holds that O-Ring in place so you really don't have to glue it except around 25mm at each endpoint where oil can enter from the gearbox. I would assume with this one you could either superglue the O-Ring stock and then put it in place or maybe butt the ends and apply a dab of Loctite 598 / Permatex Ultrablack to seal the oil intrusion point.

It makes it kind of nice as you lift the cover off and the O-Ring is held fast and doesn't fall all over stuff.

 

So here is what I ended up with the o-ring so far. I made the groove tighter than I normally would for a pressure seal. This way the o-ring stays in the groove well enough to handle without it falling out.  For those of you that don't know o-ring grooves are wider than the o-ring to give the seal a place to go as it crushes. The valve cover isn't exactly a high pressure seal and the method of attachment doesn't have enough oomph to pull the seal down evenly.  I started out with round but it seemed like it wasn’t providing enough contact area based on the mount of torque I could apply to the valve cover. I ran a square for a bit before the head shit the bed but I’m not sure if it was better or worse. My gut feeling is better because I really increased the contact area with the square profile.  Makes sense in theoryville, the land of my people.

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I sent you a drawing of the groove we use for the static seal on our gearboxes. Captures the O-Ring in whatever component you want to machine the groove. Ip to you if you want to machine the head to hold the O-Ring and keep a simple flat valve cover, or vice versa.
When I get the O-Ring spec drawing I'll let you know--that way you can scale what you have to whatever O-Ring you decide to use, wherever.

Seems to keep the throw off from the pinions at bay, they're slinging oil out at 45,000+ rpms directly at the splitline joint!

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Machine work finished!

 

I can relax a little:)

Just got done with their first bath. Still need de-buring and edge finishing but the majority of the work is done.

 

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The VCT holes are drilled and tapped but they haven’t been drilled all the way through. Easily opened up with a drill if needed. The head has provisions for three sub plates. Timing chain idler, upper tensioner and a slack side guide pivot. The idler and tensioner are connected to the oil system and o-ringed. It is getting really crowded in there with all the oil passages, head bolts and cam tower bolts.

 

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Next stop vacuum resin impregnation.

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On 1/23/2018 at 1:32 AM, Oblithian said:

Given that you need custom manifolds it seems unusual that you would opt for a tower with MPI rather than DI. Either way, I am certain a few hundred people would be interested in buying this, myself included.

 

Are there aftermarket ECU's and Injectors currently available for DI applications?

 

This is barely being touched in the OEM market at this time, do you have access to these required parts, and if so could you provide a link? Conversion is not that difficult if parts are available.

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What Tony said...Not to mention the issue with oil buildup on the valves.  I guess you could do what Subaru and Toyota and maybe others are doing and running DI and MPFI at the same time.  

 

Derek, Maybe you could whip us up a few heads with both in your spare time. :) 

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