Jump to content
HybridZ

Twin cam head for the L6 from Derek at Datsunworks


Derek

Recommended Posts

A Tale of two fuel distribution blocks.

 

There are a lot of reasons why I post the good, the bad and the ugly, but mostly because I think it really helps people realize just what goes into creating something that is truly custom. And why custom fabrication is so pricy.  Some time ago on HybridZ there was a thread about a hybrid Z car that was being sold for over a hundred grand or thereabouts. It was green just to jog some memories.  It kind of settled int those that couldn’t see the value and those that do fabrication that could. I’m being broad with my brush but you get the picture. I took one look at the pictures and immediately saw that kind on money in it.

 

So for this tale I’m the customer and the fabricator.  I’m at the point where I want to get going on the fuel system. I made all the injector caps already but I needed a distribution block so I could do the hard lines. I discussed the options with my customer and we settled on a straight block with the fuel lines one on top of the other. Much like the one I had on my car. I did a 3D model of it which included measuring the space available, measuring the distance required between the fitting in order to get a wrench on them, inlet, outlet and mounting holes. The customer approved the 3D model and I commenced to machine the block. Since there was only one I had to baby sit every operation. No screw ups. I chewed up the better part of a day by the time I was done with everything including finishing. Now if you want my undivided attention for a day it’s going to cost you $400.00 or more. So the piece looked exactly like the 3D model and functioned exactly like it was designed to do. Except the customer (me) just didn’t like the look of it in application. The customer wanted it right so we started over with a new design. Now this one took about half the time since it used all the same general measurements and tool operations so the machine work went much faster. 

So here we are with five or six hundred dollars in a simple fuel distribution block.

And that my children is why this crap costs so much:)

 

First design:

 

IMG_0755_zps2mfucshc.jpg

 

IMG_0756_zpsycohcgec.jpg

 

 

Second design:

 

IMG_0758_zps2kpcvqsb.jpg

 

IMG_0757_zps87hf3qwu.jpg

 

 

And yea I probably could have found something online that would have worked but this one is EXACTLY like I want it:) 

 

Derek

^^^^^^People laugh that JeffP has over $75,000 in his S130 (mind you that was BEFORE I started "suggesting solutions that cost him $2,000 every time we talked) but Derek exactly captures what people who ACTUALLY TRACK THEIR COSTS already know...

 

And it's what JeffP knows for sure... It sucks when you pay money and it's not what you thought it would be.

 

And it's a prime reason why a lot of the early development concepts were offline. A lot of background noise can be generated and sidetrack a concept.

 

As stated, there was a desire to make something that could be done at someone's shop if they had access to BASIC machines, or a shop with complex stuff.

 

People will hopefully appreciate exactly how exotic a component set they can buy RIGHT OFF THE SHELF if they so choose...stuff that makes an OSG head look "old technology" in the extreme. It was not the intent, but using modern technology to best advantage was a heavy design consideration.

 

Anybody who has ever lamented being able to find CNC heads, off the shelf titanium pieces, valves people actually STOCK...

 

I think the only thing we could have done to keep performance options more open would to be to use SBC Parts (Derek, about those altered Corvair 140 Head Castings we discussed some time ago...)

Link to comment
Share on other sites

Fuel lines done.

Came in on Saturday and fabbed up the fuel lines. I knew from the last time I did it that it is a tedious process. I have three marks to hit on each line. Fuel block, loom, and injector cap.  From a performance standpoint a traditional fuel rail would probably be better but this is the look I wanted and by god it's the look I'll have:) Very happy with the end results.

 

20170707040701-dcbc9d7c-me.jpg

 

 

This is why I redid the fuel block. Isn't that better?

 

20170707040704-84144292-me.jpg

 

 

The brass fitting is for the oil return. That fitting is just a placeholder for now so don't judge:)  The stainless bulkhead fitting is the rear oil supply line. All the fuel and oil fittings are Swagelok style double ferrule fittings. 

 

20170707040708-c1970065-me.jpg

 

 

And in case you are keeping track it took most of the day Saturday to fab the 6 lines. 

Edited by Derek
Link to comment
Share on other sites

Thanks for the kind words everyone.

 

Derek, I can't wait to talk options with you on this.  I have been in since day 1 and I am happy to stay that way.... although the wife might not like me..... This might make me abandon my additional LS build.....

 

You are on the "pioneer" list:) I have a funny feeling I'm going to upsetting a lot of budgetary plans with this head!

 

 

Got the oil lines run. Love the rear one hate the front one but at this point I need to keep focus on the budget and to do the front the way I want it is money that can go elsewhere.  Plus when it's in the car it will be hard to see anyway.

 

20170707040711-fd4648a9-me.jpg

 

 

 

This oil entry will be on the back side of the head and will be a part of the casting. I had to use a bulkhead fitting on this build and this was the best place for it.

 

20170707040716-a7f9e741-me.jpg

 

This will still be the front entry point in the new design but there will be more meat in the casting so I won't have to use an adapter. And yes I still haven't fixed the collision mark on that boss:)

 

20170707040713-4f10eefe-me.jpg

 

 

 

 

Now you're just showing off, and its glorious. Almost has a steam punk kind of look to it, if they were zinc plated lines or brass would be pretty cool too :)

 

Now I'm showing off.

 

20170707040734-c79aea5e-me.jpg

 

20170707040721-09e0cb15-me.jpg

 

Actually I'm starting to work on the throttle cable bracket so the ITB's needed to go on anyway. Plus a little motivation always helps.

Edited by Derek
Link to comment
Share on other sites

Old Audi 5000's (and 4000's, Coupes, and urQs) had Bosch CIS mechanical fuel injection, with normal distributors and plug wires. You must be thinking of the braided fuel hoses to each cylinder and the fuel distributor/metering head they came out of.

Link to comment
Share on other sites

Thanks for the kind words everyone.

 

 

You are on the "pioneer" list:) I have a funny feeling I'm going to upsetting a lot of budgetary plans with this head!

 

 

Got the oil lines run. Love the rear one hate the front one but at this point I need to keep focus on the budget and to do the front the way I want it is money that can go elsewhere.  Plus when it's in the car it will be hard to see anyway.

 

IMG_0768_zpsp9ia1uql.jpg

 

 

 

This oil entry will be on the back side of the head and will be a part of the casting. I had to use a bulkhead fitting on this build and this was the best place for it.

 

IMG_0770_zps7mxidtrt.jpg

 

This will still be the front entry point in the new design but there will be more meat in the casting so I won't have to use an adapter. And yes I still haven't fixed the collision mark on that boss:)

 

IMG_0769_zpserk2vkbd.jpg

 

 

 

 

 

Now I'm showing off.

 

IMG_0774_zpssbqjqmqj.jpg

 

IMG_0773_zpsd2fje8tl.jpg

 

Actually I'm starting to work on the throttle cable bracket so the ITB's needed to go on anyway. Plus a little motivation always helps.

 

Common sense tells me I should be reporting this as a provocative post. Anyway, common sense and me aren't close like. So where can I get one of these?  <_<

Edited by fuzzy
Link to comment
Share on other sites

 

 

So where can I get one of these?

 

Why come on down to your local Datsunworks dealer where December savings are in full swing. Bring a bag of cash and you can lug home a big ol chunk of cast aluminum:)

 

I will be selling them but we are aways away from that point. PM me if you are interested.

 

 

Got the throttle linkage and cable sorted out. I'm hoping the stuff I got with my econo kit from EFI Hardware works out well. Single cable pulley for 6 venturis may be asking a lot. The cable pulley is progressive so it may be fine.

 

I had to make a throttle stop bracket to make all the bits work.It's sandwiched between the cable pulley and the throttle body.

 

20170707040748-6bc17272-me.jpg

 

Throttle cable bracket. Going to lead the cable over to the firewall and incorporate it into the stock bell crank. 

 

20170707040737-609738e2-me.jpg

 

The single return spring was just a little light to return the throttles. The kit came with a lever and extra spring so I stuck them on the end.

 

20170707040750-bf3c63bd-me.jpg

 

 

I was going to cut it down but then it occurred to me it would make an excellent whoombahh lever.

 

Here you can see it in the whoom position:

 

20170707040742-532522cf-me.jpg

 

And now in the Bahh:

 

20170707040745-95accfcb-me.jpg

 

 

I believe this may be the single most important addition I've made so far. It's starting to interfere with production though. I sit out there for hours.......Whoom.....Bahh...... Whomba whoomba whoomba...  MMMMM  ITB's

Edited by Derek
Link to comment
Share on other sites

Could also use the Whomba lever for cruise control :P

 

Yes but how would I whoombahh.

 

I have my cruise control hooked up to the bell crank. That's one of the reasons I'd like to keep it or a version of it if I can but that would be a good spot for sure.

Link to comment
Share on other sites

The 1/4" lines are feed. Look back at the most recent pics and you'll see a brass fitting in the back of the head. This is the main oil return. I have a 3/4" tube swageloc fitting on the way. I'm going to hard line it down to a bung I welded in the pan. I have a smaller hole at the front that will spill oil into the timing chain area.

 

I tapped both of the 1/4" feed fittings and have installed screw in orifices. This way I can dial in the amount of oil being distributed. Right now the total of both orifices is the same square inches as the stock L6 2mm hole. The front one is slightly larger than the rear to account for the two tensioners.

 

The plan is to get the oil pan and front end buttoned up and the head as you see it installed and torqued down. I'm going to make a priming rod and spin the pump up to idle speed. Hopefully the oil pressure will be good indicating that the mains and rods are in good shape and not bypassing too much. If it's better than good at idle I'll open up the orifices a bit. There is more after that but that's the first step. By letting the orifices free flow with no restriction I'll have a worst case idea of how much oil is going to the bottom end.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...