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Just bought a 521


mainer311

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6 minutes ago, Crashtd420 said:

Mainer311 you said you got the valves from datssport but where did you get the valve guides from?

 


Valves are from Riley at Lynchburg Nissan, but they’re actually SI valves. The P/N’s he lists are identical.

 

Guides are ITM brass from RockAuto. Same all the way across. P/N VG818BR.

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32 minutes ago, mainer311 said:


Valves are from Riley at Lynchburg Nissan, but they’re actually SI valves. The P/N’s he lists are identical.

 

Guides are ITM brass from RockAuto. Same all the way across. P/N VG818BR.

Thanks, I have the valve guides in my cart already with a couple other things I need for the disk brake conversion..

 

I might order the valves for the future, I know at some point I'd like to do more work to my cylinder head..... 

 

Looks like the 43mm intake valve fit no problem being only 1mm bigger, did you give any consideration to the larger exhaust valve?

Could you fit the 38mm vs the 35, I have to assume it fits if they sell it but is there a benefit?

 

 

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Well, the actual OD of the intake seats are still larger than 43mm, so you can slightly cut the 45 degree angle a little bigger/deeper and still be fine. The valve will be within the OD still.

 

I’m not completely sure about the 38mm exhaust valves. I think you have to install larger seats for those to work properly, which means machining the head. I’m trying to avoid any of that.

 

The tool that I’m going to use for the 45 on the valve seats is from a company called Neway. I’ll need to buy the tool that has a cutter body that is slightly smaller than the intake valves, and adjust the inserts as necessary. The reason for this is because the intake seats come right up to the sides of the combustion chamber walls, and a larger tool wouldn’t fit.

 

Tons of information here:

https://www.newaymfg.com/cutters

Edited by mainer311
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46 minutes ago, mainer311 said:

Well, the actual OD of the intake seats are still larger than 43mm, so you can slightly cut the 45 degree angle a little bigger/deeper and still be fine. The valve will be within the OD still.

 

I’m not completely sure about the 38mm exhaust valves. I think you have to install larger seats for those to work properly, which means machining the head. I’m trying to avoid any of that.

 

The tool that I’m going to use for the 45 on the valve seats is from a company called Neway. I’ll need to buy the tool that has a cutter body that is slightly smaller than the intake valves, and adjust the inserts as necessary. The reason for this is because the intake seats come right up to the sides of the combustion chamber walls, and a larger tool wouldn’t fit.

 

Tons of information here:

https://www.newaymfg.com/cutters

Ya it seems the 38mm would be a tight fit.... 

Not sure if it was done but are you planning to clean up the combustion chambers at all?

Descrouding the valves is a good idea, also you can clean up the spark plug hole opening and get rid of the exposed threads if any.... 

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9 hours ago, mainer311 said:

I’m probably just going to leave it. It’s an open chamber head, and I don’t want to mess up the volumes.

thanks for the info on the valves, I just submitted a request to buy a set.... 

My luck they won't be available when I go to do more work to my head in the future,  better to just order and have them .....

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Yeah, price isn’t too bad for them. My head came with an...assortment of valves, so I figured I would just replace all of them.

 

Just bought a 0.315” hone from Amazon, so that I can clean up the guides. A couple of them are tight enough where the stem won’t go through.

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Yeah, that's the difference between hot/cold and vacuum vs. pressure. Same reason the valve lash is different. 

 

Tomorrow, I'm going to attempt to surface the manifold side of my head and install M8 stainless helicoils. 

 

Just got the front cover back from powder. 

 

Zz7nTYY.jpg

 

 

 

Edited by mainer311
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RE:

On 12/1/2020 at 4:11 PM, datzenmike said:

NISSAN OHC......Used on '76 an on L20Bs

 

DATSUN OHC.... L16s after '70, '74 and '75 L20Bs. L18s on '73 610, '74 710 and '74 620

 

DATSUN 1600 OHC Fins over cam sprocket or stop at cam sprocket before '71 on 510 and 521. I think fins over sprocket the earliest. Had them on my '68 510 and put them on the L20B I transplanted into my '71 521 which had fins stop at cam

 

 

DATSUN 1000 OHC ....

 

file.php?id=49844

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Well, the manifold surface of the head is cleaned up. Only took about .007” to get rid of most of the pits around the t-stat mounting surface and around the ports. I’ll clean up the ridges with some fine sandpaper. 
 

Also drilled and tapped all the holes to get ready for helicoil installation.

 

7njwBwo.jpg

Edited by mainer311
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