Help me match the right head

[RTB]

I'm going to bore out my l20 into a 2.2 and will be using NAPS-Z pistons. I have several heads to choose from but I need help figuring out which would be best. I have an A87 open peanut head, a w58, a 210, and a closed u67. Can anyone offer any advice? I figure I can run around 10:1 compression ratio. I plan on running 44mm mikunis but I may also use 44mm webers instead. I don't want to spend dayscleaning up every single head that I have so I rather just get good advice on what gives me the most power without destroying my engine.

[DISLEXICDIME]

we need pics of the u67 i have never seen  a closed u67  did you weld it closed?

 

what gas do you want to run?

[Tristin]

Whats an open peanut head?

[Kirden]

Whats an open peanut head?

 

Open your mouth and look in the mirror Tristan   :fu:

 

Anyways, from the research I've done, it would seem like you would want a closed chambered peanut head for high compression because the combustion chamber is designed to reduce pinging. The quinch area is better for these applications. Double check to make sure that your A87 isn't the closed chamber, becazuse I've never heard of an open peanut head either. If it is closed, that would be the one I would use.

[flatcat19]

U67 peanut, eh?

 

Oics?

[wayno]

As far as I know, all U67 heads are open, but that doesn't mean that you don't have a closed head, I just have never seen one.

A87 heads can be open or closed, they also can have small or large valves, so what you need to figure out is what exactly you have.

The 210 is good for scrap or an L16, and the W58 is not what you want unless you have a round port exhaust manifold.

[datzenmike]

First you can't make a 2.2 by simply boring an L20B and adding Z22 pistons. This combo would only be 2041cc in size and have a compression in the 7s. You will need the Z22 crank as well. Basically making a Z22 out of an L20B block.

 

There are no closed U-67 heads, although the U67 is likely the best choice for port and valve size and allows square L16 manifolds to be used.. Compression is 8.9 (depending on which Z22 piston used) Any closed chamber head would be 9.22 (again depending on which Z22 piston used... it could be less)

 

A 210 head really only works on the L16.

 

A head can be open or closed but not both.

[LenRobertson]

Here is the primer on cylinder heads if you haven't already found it:

 

http://www.davidcmurphy.com/olddat/html/tech/head_ID_2.htm

 

"Peanut" is a nickname for closed chamber head, so the terms tend to be use interchangeably. I don't know of a nickname for an open chamber. Might be time for Ratsuners to make one up. "Lima bean"? Hmm, have to think about that. :D

 

One possible consideration is how much a particular head has been planed down if it has been run hot and warped (maybe more than once) in it's lifetime.  I once got a W53 closed chamber head which had been planed down so far the bottom face was cutting into the casting letters on the side of the head. Which needs to be taken into account calculating CR. There is a spec in the first paragraph of the head page on what unmilled head height should be.

 

Len

[RTB]

Sorry I was being a total noob about heads. The a87 is a closed head. But in reference to boring the block, I have longer rods so Ican uuse the same crank but use the z22 pistons and have them act as flattop. I'm just worried about compression ratio...

[LenRobertson]

I remember when I first started reading about the different combustion chambers and terminology, it was confusing. Someone should work up a Datsun/Ratsun dictionary and post it.

 

I've seen an online CR calculator, but don't have a link to it. Maybe someone can post the link. I'll look for it when I get back home if I get rained out at work today. Looking at the precip radar map, that looks very likely.

 

Len

[flatcat19]

I remember when I first started reading about the different combustion chambers and terminology, it was confusing. Someone should work up a Datsun/Ratsun dictionary and post it.

 

I've seen an online CR calculator, but don't have a link to it. Maybe someone can post the link. I'll look for it when I get back home if I get rained out at work today. Looking at the precip radar map, that looks very likely.

 

Len

 

The Helix tool.

It's pinned in the engine section.