Lets do some bench racing: DIY Dohc head

Been reading about putting a ka24de head (newer style dohc head) onto older Lseries 4 cylinder motors.

Would it be possible to splice together two (maybe 3?) heads to make a 6 cylinder version?

Just some random musings I have had today

That sort of thing can be done but it takes some pretty good welding talent. I once read about someone who spliced together a couple GM Quad 4 heads and then put them on a 1960s era Pontiac overhead cam 6 engine block.

If the bolt patterns line up (or can be made to do so), sure.

This guy glued two ls1 heads together to make a ford big six head. http://bangshift.com/bangshift1320/mad-science-a-drag-racer-sliced-and-diced-a-pair-of-ls-heads-stuck-them-together-and-mounted-them-on-a-ford-inline-six/

What type of welding would be used? I would assume tig?

Definitely tig in some sort of jig fixture to keep things square. Guessing there would be a healthy amount of machining at a head shop afterward to clean things up.

Anything is possible with enough time and money. For a short period of time there were guys putting 32V Porsche 928 heads on BBC V8.

Same concept Here leads to a V12 LS..

This has got all sorts of wheels turning in my head.

Moving on: what could be done for cams? Custom or could teo be joined to create one like the v12 LS?

I think for an OHC I6 you'd need custom cams or chunk them into 6 pieces (and weld them back up with a big jig) to re clock them, since the 6 will have the crank pins 120 apart, rather than than 180 you find on all car 4 cylinders.

Someone has done exactly what you propose. Look up "1 fast z" / blake machine co on zcar.
http://www.zcar.com/forum/13-car-talk-forum/271194-dohc-engine-running-yes-running.html

I don't think the story ended well though.

Also, OS Giken has / had one in Japan, I think?

Fitzauto wrote: Been reading about putting a ka24de head (newer style dohc head) onto older Lseries 4 cylinder motors. Would it be possible to splice together two (maybe 3?) heads to make a 6 cylinder version? Just some random musings I have had today

It has been done.

OTOH I was reading about it about 15 years ago on one of the probably now defunct 240Z sites. So I won't even try to find a link. I forget what was done for camshafts.

Personally, I'd just as soon buy a nonturbo RB engine for peanuts and use that.

(Three minutes late... darn )

Kenny_McCormic wrote: If the bolt patterns line up (or can be made to do so), sure.

The KA directly traces its history to the 4 cylinder L engine.

Somewhere I was thinking that the RB traced to the 6 cylinder L but it sounds like that isn't the case, if people would rather hack up a pair of KA heads.

1 fast Z isnt willing to share information at all.

The ka head is easy to come buy but an NA rb could be fun. Just dont know where to look and would like to keep it L series if something like this happened.

I helped a guy build a straight 8 (Buick?) with 2 Toyota 20(22)R heads welded together.

He bored out the cylinders and fit larger sleeves into the block, the deck height was shortened to match the Piston/rod combo, a new deck was fashioned to match the toyota bolt pattern and water flow needs. The cylinders and deck were furnace brazed (silver soldered) together. A work of art 8-4-2 header was made from thin wall stainless tube.

This motor was designed to make an assault on the 32 ford vintage class (prewar motor, block & crank) at Bonneville.

I lost touch with the project and have always wondered if he was successful.

In reply to bentwrench:

That sounds awesome

I would try yahoo Japan auctions. Once in a rare while an OS Giken head pops up. They go quick and usually for four digits (still) but it would be cheaper than splicing heads and hoping for the best. I second the RB swap. I had a rb20det in my s13. Great little motor, and you could tell the "R" in "RB" stood for "racing breed" that engine wouldn't quit.

Kenny_McCormic wrote: If the bolt patterns line up (or can be made to do so), sure. This guy glued two ls1 heads together to make a ford big six head. http://bangshift.com/bangshift1320/mad-science-a-drag-racer-sliced-and-diced-a-pair-of-ls-heads-stuck-them-together-and-mounted-them-on-a-ford-inline-six/

I read some of the link posted here from zcar and I don't think it's the same as this other z car guy, who cast his own from mostly Honda k series design http://forums.hybridz.org/topic/119641-twin-cam-head-for-the-l6-from-derek-at-datsunworks/

It's pretty common to stick Dodge Neon DOHC heads on the old 2.2/2.5 SOHC Turbo Dodge blocks.

Look up Turbo Dodge Hybrid 2.2 or 2.5 to get started. It's nearly a bolt-on ordeal after a few special pulleys are installed and some ports blocked off.

An rb20 is on the table as far as potential swaps go.

Derek's head is nuts and Im pretty sure I dont have the time or skill to replicate his build.

Quad-turbo V12 2JZ

It's pretty common to stick Dodge Neon DOHC heads on the old 2.2/2.5 SOHC Turbo Dodge blocks.

Look up Turbo Dodge Hybrid 2.2 or 2.5 to get started. It's nearly a bolt-on ordeal after a few special pulleys are installed and some ports blocked off.

If you have an engine in mind to put a better head on, I'd start with the bore spacing because that will be the most important thing to get stuff to line up.

The 2.0/2.2/2.4/2.5 also share their 96mm bore spacing with the Nissan KA engine, the Lotus Elan, and others.

I saw 4 slice and dice DOHC Subaru heads get welded up to make a DOHC Chevy small block.

This is all crazy talk. Just buy what you want. It's like "why swap auto to manual?" Just sell the car and buy it manual!

flatlander937 wrote: It's pretty common to stick Dodge Neon DOHC heads on the old 2.2/2.5 SOHC Turbo Dodge blocks. Look up Turbo Dodge Hybrid 2.2 or 2.5 to get started. It's nearly a bolt-on ordeal after a few special pulleys are installed and some ports blocked off.

That isn't much of a swap given that the Neon engine is more or less a short deck, internal water pump 2.2.

If you wanna see fun, look at the guys putting BMW motorcycle engine heads on Mini blocks, or Porsche 928 heads on (I think) big block Chevys.

Even those aren't as involved as major head surgery to splice two heads together...