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Holy Grail Teaser


Xnke

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l28 alluminum block and dohc alluminum head (that doesnt cost $10k)

 

ill pay that

 

The block would be easy... just copying the pre-designed L6 block and then adding thickness/strength/ribbing to it for the weaker aluminum material. Block girdle integrated etc...

 

The head is going to be the expensive part. Lots of engineering going on there.

At $20/hr which is VERY cheap... labor costs for the CAD design of a block will be over a grand. I wouldn't take much less.

The head design would cost more with all of the moving componets, cams, etc...

 

If you were to build a one-off motor you would have over $20K into the longblock unless you are the guy on the CAD and CAM with free time and your own machine shop to use for free.

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The machine work alone will run you close to a grand, if you are very lucky. Probably closer to 2K$.

 

Derek is right, patterns like these are godawful to get right, even on a smaller scale. Let's look at what I figure I'd have to do to mold the "Paeco-Goerz" DOHC head:

 

Patternwork: working from finished, error-free prints, 150 hours.

 

Molding: with an error-free pattern, minimum cope, cheek, and drag mold, plus the multitude of cores needed. probably gonna have to use a two- or three-part pattern. probably 30 to 40 hours to figure out the molding, and practice to get it right, every time.

 

Pouring: the easy part. 25 minutes to pour, 45 minutes to solidify and harden, 6 to 8 hours to artificially age, at least a month or two to precipitation harden, (Heh, iron is one to two years before you should machine it, depending on the size...)

 

Machinework: probably 50 hours on the first head, after that, 4-8? lots of drilling, tapping, and precision work.

 

I'ts gonna be a bit...Anyone got a KA head in solidworks? i could mod the design to be similar to 1 fast z's, and see about gettin patterns made up on the CNC machines at school...

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Because you can't buy a DOHC head for a Z.

If you find one I'm sure it would cost you 30k by now.

that's IF you find on.

 

I say we cast up 1 fast z's head haha.

 

agreed. After all, we already know it works. Plus, once there are a multitude of DOHC heads out there, people will start messing around with them and figuring out changes.

 

 

Though IIRC, you can't use the normal L series intake stuff on that head, which kind of sucks. I wouldn't mind a DOHC with triple Mikunis....

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If it came down to a DOHC head or an aluminum block, I would pick the DOHC.

I agree.

 

IIRC, didn't someone take a couple of KA24 head, chop them up, and then bolt them all together?

 

Yes, 1_fast_Z did it. look up "l31dett" and you should find it.

 

If we could get something like that as a single unit, that would be awesome. Especially if the intake side could take all the normal L series stuff (Webers, Mikunis, etc).

 

I would think it probably wiser to base the intake ports off of another pattern already commercially available.. say, maybe a BMW or Toyota or an RB pattern.. so that we would already have a commercially available base of intake parts to work with. The non crossflow stock head means that the intake runners are not evenly spaced, which is less than ideal. If we could find an engine like, say a mercedes benz, that would have both fuel injection and weber/solex intake manifolds for it, then so much the better.

 

 

Its all bench racing, though, unless one or two people pick up a lead role and run with it. I for one, love talking about this sort of thing, but can't do much to make anything happen. Anyone want to volunteer for quarterback?

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It would be much easier to put an RB26DETT head on an L6 than to build a whole new head. Just block off the oil passages and route oil from the outside of the head.

I'd rather spend a grand on a modified RB26 head to work on an L6 than a whole new head. There are already turbo cams available, valvetrain componets, etc... Plus you can use a higher displacememt with an L6 than you can with an RB. (RB 3.0 vs. possible 3.4-3.5 with a max effort L6)

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Would that work though? Are the bore spacings the same on the RB head as the L-series block? same with things like the water passages and the bolt pattern.

 

Converting the timing system wouldn't be as bad though, you can always convert the pully's to chain driven.

Well, even then you COULD block off every water AND oil passage, and have all that externally routed, but I think you'd have to also add extra coolant lines to make sure it flows from the block to the head correctly, otherwise it'll disrupt the cooling and oiling flow, right?

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Yes, 1_fast_Z did it. look up "l31dett" and you should find it.

 

I would think it probably wiser to base the intake ports off of another pattern already commercially available.. say, maybe a BMW or Toyota or an RB pattern.. so that we would already have a commercially available base of intake parts to work with. The non crossflow stock head means that the intake runners are not evenly spaced, which is less than ideal. If we could find an engine like, say a mercedes benz, that would have both fuel injection and weber/solex intake manifolds for it, then so much the better.

 

 

Its all bench racing, though, unless one or two people pick up a lead role and run with it. I for one, love talking about this sort of thing, but can't do much to make anything happen. Anyone want to volunteer for quarterback?

 

yah, I found that thread after I posted that. That is the exact head that I was thinking of.

 

As for designing the intakes around a different manufacture (makes sense now that you wrote it down), are the weber/solex manifolds compatible with Mikuni carbs? (I don't know NEARLY enough about this kind of stuff).

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At one point they were 10k, but NOW there are NONE. zero. if you find one you could sell it for however much you want. hell, I'll bet just the head, stripped of all the valves and cams would be worth close to 10k

 

The OS Giken head is like THE holy grail of Z cars. Everyone wants one, no one can find one for sale. I can only think of (besides that picture) One, maybe two cars that are running with it.

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First off, I want to say that part of me hates stepping into bench0building discussions like this.. because I do freely admit that most of it is largely over my head.. but I know how far over my head it is, so I feel somewhat comfortable talking about it, and this is too tempting to resist :rolleyesg

 

It would be much easier to put an RB26DETT head on an L6 than to build a whole new head. Just block off the oil passages and route oil from the outside of the head.

I'd rather spend a grand on a modified RB26 head to work on an L6 than a whole new head. There are already turbo cams available, valvetrain componets, etc... Plus you can use a higher displacememt with an L6 than you can with an RB. (RB 3.0 vs. possible 3.4-3.5 with a max effort L6)

 

I could not possibly disagree more. if it only took a grand to put an RB head onto an L6 with external oiling and cooling, then it would have been done seventeen million times already..

 

To me, the two possibilities involving casting new pieces, and the L-6 engine series, would be to

 

A: Cast new aluminum blocks

B: Cast new crossflow, DOHC aluminum heads

 

Now, the difficulties of, and advantages in either possibility have been discussed at length. To me, the reality of setting up molds for a complete, internally cooled new engine block, is a manifest show-stopper. However, if KA series heads were already modified and sandwiched into a head, then why can we not find KA heads to section up in order to prepare a mold, sculpt an "ideal" combustion chamber (or even weld up and fill in a combustion chamber for complete customization after casting) and find a way to make the camshaft question work? Proven valvetrain components exist, the bores line up.. I hate to sit here and blatantly suggest we all copy what was just pioneered, but.. the realities of casting a head seem to me to be more surmountable than those of casting a complete block, and that aluminum block would still have to breathe through an L-series head, OR you would have to pioneer installing an RB head onto what is still an L block.

 

To me, when thoughts of CHANGING either the block, (to accommodate the RB head) OR the 240SX head design, (any changes needed? intake port alteration like I mentioned above?) are concerned.. then the entire ballgame is changed, and you are departing rapidly from reproducing and beginning to engineer your own animal. Therein lies even more potential for difficulty and time to snowball on this kind of project.

 

 

 

Whatever we may all agree or disagree on, my point remains.. without a captain, this ship is most likely going nowhere fast.:sour:

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I too hate participating in dreams but I'm trying to get my post count up so I'll just jump in.!

The head idea is in my opinion a much better idea. I would think that casting more of a blank as far as the combustion chamber is concerned and plan on having it machined on a 5 axis CNC mill would be a better way to go. Trying to get people to agree on a standard size and design might be problematic. I also agree that basing it on existing manifold designs would make things easier as well. If it had the stock port spacing but was a cross flow design then theoretically after market headers and intakes would bolt up to the head. Now the problem is the tilt of the engine reduces the room you have for intake system on the passengers side of the car. On the drivers side you have 15" from the head to the shock tower. on the passengers side you only have 10". For a NA motor this may be tight.

 

This kind of stuff costs big money and for what you would have to plunk down to make this work you could install a RB motor and still have some left over.

 

Just my opinion!

 

Derek

 

First off, I want to say that part of me hates stepping into bench0building discussions like this.. because I do freely admit that most of it is largely over my head.. but I know how far over my head it is, so I feel somewhat comfortable talking about it, and this is too tempting to resist :rolleyesg

 

 

 

I could not possibly disagree more. if it only took a grand to put an RB head onto an L6 with external oiling and cooling, then it would have been done seventeen million times already..

 

To me, the two possibilities involving casting new pieces, and the L-6 engine series, would be to

 

A: Cast new aluminum blocks

B: Cast new crossflow, DOHC aluminum heads

 

Now, the difficulties of, and advantages in either possibility have been discussed at length. To me, the reality of setting up molds for a complete, internally cooled new engine block, is a manifest show-stopper. However, if KA series heads were already modified and sandwiched into a head, then why can we not find KA heads to section up in order to prepare a mold, sculpt an "ideal" combustion chamber (or even weld up and fill in a combustion chamber for complete customization after casting) and find a way to make the camshaft question work? Proven valvetrain components exist, the bores line up.. I hate to sit here and blatantly suggest we all copy what was just pioneered, but.. the realities of casting a head seem to me to be more surmountable than those of casting a complete block, and that aluminum block would still have to breathe through an L-series head, OR you would have to pioneer installing an RB head onto what is still an L block.

 

To me, when thoughts of CHANGING either the block, (to accommodate the RB head) OR the 240SX head design, (any changes needed? intake port alteration like I mentioned above?) are concerned.. then the entire ballgame is changed, and you are departing rapidly from reproducing and beginning to engineer your own animal. Therein lies even more potential for difficulty and time to snowball on this kind of project.

 

 

 

Whatever we may all agree or disagree on, my point remains.. without a captain, this ship is most likely going nowhere fast.:sour:

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