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I always seem to get asked about these head builds often, so I thought it might be interesting to show how I do them. This particular set is a 390 closed chamber casting, I will prep the head and install new valve guides, cut for seals, unshroud the chambers and machine for 1.880/2.190 valves then surface, and finally assemble. The first step is checking for core shift, this is done by placing the intake gasket on the intake face and looking how well the ports line up with the gasket with the bolt holes centered, if they don't, don't waste your time. The heads are then cleaned and magnafluxed, then all the holes are tapped and the chambers are scribed.
 

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More please.
 

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On older head casting I usually replace the factory knock in guides to get fresh metal to work with. The factory guides are gang drilled after they are installed in the head, the OD is not concentric with ID, so if any guide repairs are done after the factory valve job you will have a sunk valve unless going to a bigger valve. Replacing the knock in valve guide also can make the head more responsive to porting by moving the valve more towards the intake face.
 

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The bronze guides are then broached and trimmed and cut for a positive seal. After the bronze guides are installed the they will need to be honed to size, this must be done to size the guide and make it strait and round. Perfectly strait and round guides are the first step to a perfect valve job. The tools for the job. The honed finished guide below.
 

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The intake valve job, after the seat is cut run out is checked, it will be under .001. The valve should bounce off the seat when dropped, after valve rests on the seat the valve is "tapped with the index finger in the center of the valve head NO movement should be felt". Intake valve angles 35/45/60/75.
 

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Very interesting. Due to the fact I am a geeser I enjoy looking at pictures of a modern day "" HEAD JOB "" LOL !:surprise:
Bob
 

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The first step is checking for core shift, this is done by placing the intake gasket on the intake face and looking how well the ports line up with the gasket with the bolt holes centered, if they don't, don't waste your time.
I'd love to see a picture of what you find that is not acceptable.
 

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Mark, knowing you're going to use liners, do you start with a 3/8 replacement guide or 11/32? Do you use a sealer on the exhaust guides?
Good thread. :thumbsup:
I use a 3/8 replacement guide, core drill it for the liner, from there I can go 11/32 or 3/8 on the guide liner. On the exhaust I use green Loctite on the exhaust, oil on the intake guide.
 

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The exhaust seat is cut with a radius. Valves are lapped to check contact patch. Valve depth is set.

Very good thread I can truly see why your engines make good power, I see you take great pride in your cylinder head work and the end result are epic.

Thanks for sharing
Carl
 

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Discussion Starter #18
Mark do you correction cut the intake face of the head so any intake will fit out of the box ??
These heads were cut .010 and will used on a block that has not been decked 9.800 so I did not cut the intake face. But I have before. Thanks for the nice comments.
 
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