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Discussion Starter #1
Basically doing a mild port and polish on my spare SR20De roller head.

Cleaning up the inside ridges:


Deburring the head:


Allmost done with the intakes:


Valves removed so I can get to the bowl, talk about carbon buildup on the exhaust side :eek: :


The last pic I don't know if it's ok to touch(grind/blend) the ridges on the bottom of the valve seat. They are kinda like knife edges and look like flow inhibitors to me.

Any opinions?
 

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Nice. I was told to smooth out the bowl but not to take out to much material or change the shape.
This is a before shot of mine.

And after. (It still needs a little work) You can see I took out the rough casting marks on the exhaust side under the valve seats.


Next I'm going to remove the valve guides and make the transition a little smoother. I did a lot of the work on the ports with a dremel and a flap wheel and most of the seat stuff was done with a small grinding stone and a small wire wheel to polish it out.

More pics here:http://www.sr20.net/v/mikeG/DET/clean/port/?

Mike
 

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Just be *very* careful not to nick the valve seat. It's not an easy task and you need a real steady hand. ;)

Mike
 

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Discussion Starter #5
I should be all-right.... What did you use to polish the bowl/combustion chamber.

Thanks for the warning :)
 

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I used a small soft wire wheel attached to a Dremel. I haven't polished the combustion chamber with it yet. You will probably be better off using air tools to do the polishing because they can produce more rpm.

Mike
 

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i have a complete spare engine....what kinda gains are u's looking to accieve by doing this>?? im just debating if its owrht P/ping it & then swaping 1 head from the motor thats sitting in the garage to the one in the car
 

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Hmm I'm not really sure on the gains. I'm just really doing it because I can and I figure any gains I get are just a plus ;) The head I have is from a DET that I've been working on for a while now.

My plans are to sell the det block and swap the high port head onto my low port motor. I'm also going to be freshening up my bottom end with arp rod bolts and new rod bearings when I bolt the turbo kit on. I really won't have any way to tell if I get any gains..

Mike
 

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Discussion Starter #9
Mike Gosselin said:
Hmm I'm not really sure on the gains. I'm just really doing it because I can and I figure any gains I get are just a plus ;)

Mike
My reason also.

If done properly there should be gains but no way to tell unless I get it flowbenched or installed on the car and strapped to a dyno... Then still no way to tell because I didn't get it dyno'd/benched before I started.

Some guy on a ford site built his own flowbench and got a a gain of 15%.
 

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Discussion Starter #10
16 valves, springs and retainers.....


How do I get the crud off the valves/stems without scratching them?
 

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I soaked mine in parts cleaner then ran them under a soft wire wheel until they were clean. It took some time but they came out perfect. I have a 1/2 hp electric motor that plugs directly into a 110v wall outlet and I have the wheel bolted directly to it.

Mike
 

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Discussion Starter #12
Will try that, thanx :)

I have a 230v digital Dremel Professional which runs 33000rpm at full throttle :)
 

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heh.. The nylon wheels suck. Try looking for a wire wheel attachment for the Dremel at the hardware store. Get a soft one and let the rpms do the work for you.

Carbon is a tough mo-fo to remove. Let the stuff sit in some petroleum product to loosen it up a bit then go at it.

I had my head beaded to get it clean and it was a huge mistake! It came out clean but.. beading material was stuck deep within all of the oil galleys.

You can see here I had to drill out the galley plugs and have the head re cleaned. I then had to replace the plugs with allen head set screws. :(

New plugs..


Mike
 

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Discussion Starter #16 (Edited)
Used the nylon one to keep the valve seats from being scratched. Got the carbon on the seats as well....

Before I "attack" the carbon with a metal brush I'm thinking of buying carb cleaner to see how that works. Brake cleaner was a no-go, pain-thinner worked a bit, carb cleaner should get the crap out. If not I'm off for an acid bath.
 

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I just stick em in the drill & get busy with the wet & dry ........ You gotta be carefull but they ain't made O' chocolate ......... I use a drill to lap em in too ....... Wodananimal

:beard:
 

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Use concentrated caustic soda or washing soda, that attacks aluminium but not steel.

Mike
 

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Pizdeet kak Trotsky
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You can just see the chaps in the garage donning the pink rubber gloves & bathing there components in the corner ;)
 

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Thats some hardcore shit fellas! :shock:

Its cool you are taking pictures. I like seeing all this. Its nothing I will ever see in my engine. LOL
 
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