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L20B head job


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I blew the head gasket the other day, and since I'm in that period of time with no money. i'm using parts that I had purchased a while back. So instead of using the head that came off the block. I'm using a W53 close chambered peanut head. My question is if I did the stupid act of mismatching the exhaust ports between head and manifold will it seal ok?

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A round exhaust port head can be fitted to a square exhaust manifold and run without too much worry but square port into round manifold is rather iffy.


Hold the L20B manifold up to the head and take a good look. Test fit the gasket and see if there are any gaps. I don't know weather to use square or round gasket... i've never heard of this working this way.



Why change the head? Check to see if warped first at least. I blew my W-58 gasket... for no reason I could see except 300,000Kms? Looked good so threw $23 NAPA gasket on and kept rockin'.

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THank Everyone who read this. I was able to find a square port manifold this morning. And for my next trick. I'm getting some money together and am going back to where I found the manifold and picking up both A87's I found and have them rebuilt. Any how I should have my pickup back road worthy tomorrow. Just wanted to say thanks to those who helped with the issue.

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What is the status of the w53 head? They are older than the w58 so will most likely have more wear. New seals would be a must and maybe a valve grind which doesnt cost that much. Peanut wont necessarily mean more power. The stock L20b heads larger ports will create more power than the smaller chamber. It will have more torque but the fun is in the top end with a l20b.IMO. At least port match it to the intake mani if you can. Which brings me to that point. The stock intake mani for the l20b with w58 might need a few things blocked off. More work involved than just swapping the exhaust mani.

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I was fortunate to findnthe W53 on ebay completely remanned. After winning the head I did take it to a machine shop to see if anything was missed. Since my pickup has the electric fuel pump I'm using the block off plates that were on the original head. As for the power aspect. I know these vehicles are fun as hell. But, I'm far from a novice when it comes to mechanics. The basic idea was just to get the old girl back on the road and me to work. So I'm using what I already have and what I'm able to interchange. One oif the best parts of doing this for me is the fact that I'm working on the truck behind a friends shop. I guess you can say I've my own on site mechanic. He helps me with alot of my technical questions. As the progress goes along I will take some photos and post them. For any additional info that might help me out.

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As for the intake. I've matched it up to the head and it fits perfectly. I picked up a non egr intake on ebay as well. The head displayed round port intake square port exhaust. The original intake I had already blocked off when I removed the EGR system.

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