Chasing the Ghosts of LeMans - Thunder - Project 487 Super Snake

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Originally Posted by FETorino

Don't know who's selling you the story of cam clearance with that size crank. I'm running a solid roller that is bigger than any usable hydro and no issue there, no real issues with the 4.375 stroke period except the upcomming traction problems. Now 4.5 like Jay Brown originally went to run in his HR that's a different story.

Well, maybe I'll have to do more research.

For now I got another few hours of porting and polishing done. I decided to work on the combustion chambers. UNshrouding the valves, spark plugs, and chamber.
I have one head roughed out, and a system now, for what I want to do.

After the chambers, I'll tackle the bowls.

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A few pics of the combustion chamber work (whew this takes a long time) Work on the chambers, unshrouding the valves, a little radius work around the spark plug relief, and a polish to 800. Once the chambers are all done, I'll CC them, and after that they get a final polish.

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Well back to the grind, or should I say grinding.
House renovation project is finished.
I think I have the intakes on one head done, on to the next head, and then the exhausts.

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A few more pics, of the head work. Close to 2/3 of the way through, I think.

Sometimes I get the idea to do things a little different,as the heads progress.

Generally pretty close. A little more polishing of the exhausts and chambers.

[FETorino]

Are you going to flow the heads when you are done?
Who is doing the valve job?

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Originally Posted by FETorino

Are you going to flow the heads when you are done?
Who is doing the valve job?

Yeah I'd like to flow the heads, if I can find someone local, who does this.
I'm actually being pretty conservative. Port match the intakes. I opened up and ovaled the exhaust ports slightly. Widened the bowls around the valve stems, and unshrouded the valves and spark plugs slightly.

Spent a little time on the long turns, and roof of the ports. I didn't want to lose any velocity on the intake side or create any dead spots. I'll probably leave the intake surface rough

I did very little on the short turn radiuses, smoothed edges, cleaned up the flash, and gave a polish on the exhaust side

I'd be curious to see what difference there is.

I am going to CC them, as a last step. Lots of work, esp on the exhaust.

Yeah, because of the bent pushrods, the valves and seats must be redone.

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Well the block is mostly apart, except for the cam.

I have a few more micrometers to get, and a dial bore set, and then I should have all the tools I need.

Tonight I was working on some basic oiling improvements;

Deflashing the oil drainbacks in the block.


Enlarging the feed from the pump to the oil filter adaptor to 7/16 (same size as the main gallery)


Chamfering the mains supply very slightly


Increasing the size of the drainback hole in the heads, chamfering, and polishing the "gutters" for faster drainback, less oil pooling

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Well, I think that I have the intake ports pretty much, where I want them, on one head at least.

I should qualify that a little I was mapping the air flow, with compressed air, and "think" the ports are good.



More later

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A few things are happening on the engine front.
Hopefully I'll have something to talk about in a week or two.

Lots of decisions.

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Well, I am deciding cubic inches, this weekend. Hope to weigh all the options this weekend.
465 (428 block), or 482 cubic inches. (427 block)

Most of all the other parameters will be about the same. Maybe a slight cam difference with the cubic inch diff.