New L20B EFI manifold!

[LenRobertson]

Harder to find, plus I've already done a ton of work on this head. But you make a valid point. From the original posting of this, I have decided to tear down the L20B for inspection, so I may end up going that route, who knows?

 

Matt - I have an extra peanut head. I can't remember the number, so don't know port/valve sizes. Only thing, it has been shaved quite a bit, maybe too much for your set up. When it comes to CR calculations, my brain shuts down. I can put the calipers on it and try to see how much has been taken off, if it is anything you might be interested in.

 

Len

[boal]

Man, that looks a lot like the manifold I made for CIS fuel injection for a L series.

 

Any more photos of this manifold? Also the VW throttle body connection would be nice to see!

[HRH]

Aaaack, VW? Not on MY Datsun! ;)

 

Len, if you can see how much has been cut off. The problem is the small area of the peanut head. While good for quench, (better than open head) with near flat-top pistons it very quickly starts getting into the race compression ratio area when milling off a 42cc peanut head. Or maybe they're 45, can't remember. Either way the open chamber is much more cc.

 

No worry, no hurry. I'm figuring on having the 510 down for quite a bit, and I just barely got the truck finished up, haven't even cleaned the garage and gotten the 510 into the workable side yet. And I just swung a deal to get two more 510s. :blink: Rusty, but probably fixable.

[DAW]

I don't think you'll be able to use the closed chamber head with the Z20 flat tops if the head has been cut at all. I've found the closed chamber W53 and W58 on L20B 720's, they might have been from Canada, not sure. I'm running one on an L20B with L18 pistons and it works great, but those pistons still have 4.36 cc dish (instead of L20B 11.36 cc). I give up some quench due to the dish, and I might be able to use flat tops to increase the cr while picking up more quench, but I have a stock cam. With your cam you could run more cr. IIRC, The Z20 pistons still have a slight dish plus the little valve reliefs and are not true flat tops, maybe a cc of dish. I don't remember what I calculated my cr to be, but I'm sure it was less than 10:1.

[LenRobertson]

Matt - I'll measure the head height within the next few days. I know where the head is located, and my vernier calipers. Finding anything around here is half the battle. I need to remember how to read the calipers. I don't know why I have to re-learn that every time I use them. No trouble reading a mic, and they are more or less the same.

 

I took this head to Jones and Dan said it was milled too much for something I'd want to drive on the street. He showed me where the head gasket had started to blow out between two cylinders. I mentioned head gasket shim and he said "Why screw around, just try a different head." There are no cam tower shims on the head, so I suspect whoever put the engine together didn't know what they were doing. It had fresh silicone like a fairly recent rebuild. So it ended up at Pick n Pull. May have been pinging like crazy.

 

I'll measure it and you can decide if there is a chance of you using it. I can drop it off if you want to take it and cc it or anything. Probably with the pistons you have, it won't work, but I really have no idea.

 

Len

[HRH]

Don't get me started on Jones. I had bad experiences there and they're not in operation anymore, they're part of S&S now. Haven't gone back since. I have Sunwest in Medical Lake do all my block and head work. Good guys, they know what they're doing and they give two shits about 4 cylinders.

 

A little passage between the two is just a weld away from a perfectly usable head. I'm not really needing a peanut head, though I certainly have thought about it. I'm pretty happy with the way this motor had been running, so I may just go back at the head I have. I've spent a bit of time on it, and already have it, so that may be the crux of the thing.

[LenRobertson]

Don't get me started on Jones. I had bad experiences there and they're not in operation anymore, they're part of S&S now. Haven't gone back since. I have Sunwest in Medical Lake do all my block and head work. Good guys, they know what they're doing and they give two shits about 4 cylinders.

 

A little passage between the two is just a weld away from a perfectly usable head. I'm not really needing a peanut head, though I certainly have thought about it. I'm pretty happy with the way this motor had been running, so I may just go back at the head I have. I've spent a bit of time on it, and already have it, so that may be the crux of the thing.

 

I was pretty sure Jones was on your bad list, but as you said, they are gone now. I don't know how S&S is, but when I need more machine work done, I was going to ask for your recommendation. I've heard of Sunwest, but not sure who told me about them.

 

It sounds like your head is working for you, so probably worth using it. The theory on peanut heads is being able to run a higher CR without detonation. But I don't know how much higher CR for closed vs open chamber, and if that translates into anything noticeable on the street or autocross. Maybe someone can enlighten me.

 

Len

[DAW]

See some of the discussion on Turbobricks re squish and quench. It doesn't matter if it's a red block Volvo or a Datsun. With the nice rod/stroke of the Z20E piston/rods in the L20B and a closed chamber head you have the optimum set up using stock Nissan components. The crank is fully counterweighted and the 86mm stroke is great. You can't really go up any in bore size and still use the closed chamber head. You'd need the 4 cyl equivalent to the L6 P79/P90 head where the roof was raised to expand the chamber volume (shorter valves) and still have a closed chamber head. Z22 with an L4 series head are limited to an open chamber head and even then they ping like crazy, but a closed chamber head on a 2.2L would just be too high a cr; high quench or not. On a 2.2L, if you run more dish in the pistons to use closed chambers, then you lose the quench effect. In your case, you can just get by with an uncut closed chamber head on your 2L setup. Performance is compromised with an open chamber shaved head. If you think it runs great now, you will be amazed at the difference.

DAW

[HRH]

I've seen both done. Peanut heads on 2.2 blocks, either race gas or water injection systems. You can make anything work given enough effort.

 

As far as the open chamber heads, yes they are more prone to detonation, but with the EFI, it's a lot more manageable. I haven't had any detonation issues with the flattops and .030 off the U60 head with the EFI. Running around 14 degrees timing static too.

 

Either way, I'll do some figuring. Part of it will be how good the head looks (or bad) when I take it off for inspection. Depending on what I find there, I may do something else. I'd like to find a KA20E head, actually. I've heard they come on forklifts? Only heard mention of a few of them. Probably harder to find than is worth it. And then I can't use my cool new L20B EFI manifold.

 

So many choices!

[Eric Garside]

What are you gonna do with the modified Z manifold when you replace it? ;)

 

And I am in the process of reading the twenty some pages of your FI build and it is truly amazing!!!

[HRH]

You know there's a complete 200sx in pull and save right now just waiting to have it's EFI system taken off and put on an L? I'll be selling my manifold after this, so should you want to go yank the harness/ecu/and airbox bits, I'll make you a swinging deal on the manifold. It works well, just doesn't flow high rpm nearly as well as the new manifold will. We're talking above 5500 rpm. Which if you're just looking for a daily, it's way better than carbs in every way.

[datsunwizard]

Any more photos of this manifold? Also the VW throttle body connection would be nice to see!

 

There some more, sorry for the poor quality, but they are scans from photos. Did this car in the early 80's, CIS was the cats meow back then. Pretty much a mechanical system, only a few things that are electrical. Ran very well. It was going to be turboed, thats why the throttle body is mounted on the bottom of the manifold(and before intercooling was the rage), but a guy made me a offer that I couldn't refuse, so I sold it before the next step.