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Is this head destroyed

Lean mixture melting pistons in action!

You can shave a lot off the head, but it weakens it because you're making it thinner. If you have high hp goals in the future(300whp+ maybe?), you will probably not want to use a head that's been shortened that much.

If no sharp edges and smoothed out, you will probably be fine. Have the machine shop shave what you want/need, then make sure there's no sharp edges and run it if you want. But, give that engine more fuel!
 
You can shave a lot off the head, but it weakens it because you're making it thinner. If you have high hp goals in the future(300whp+ maybe?), you will probably not want to use a head that's been shortened that much.

Ehhh, You could push a shaved head a lot more than that :)

The current engine in the rally car has a shaved head (.035"?) and it's plenty happy at 22psi with a GTX2860. But that's a data point of 1.
Granted, .060in is a bit more, but those deck surfaces are thick!

Edit: Just took a look at some 530 head slices I have. The deck thickness is approximately the same as the chamber depth.
 
I had to convert all those numbers to visualize them, I don't speak imperial measurements too well. Ill measure the heads current thickness (I think I read an old thread and one of you said 142.6 or 146.2mm? stock) and see if its lost any material in its 30 years of life.

I think the overall plan for now is to practice porting the head, then depending on how it turns out (I may post up pictures here when I get to it) and either take it to a machinist for the 46/38mm valves or get another 530 that wont need to be shaved and take the port practice over to that one. My hope is to run E85 on 80lb injectors instead of 91 octane on 42lb injectors before this head touches my motor again. Regardless of if its this one or the next one I'll have a LOT more fuel to keep the temps down.

Plus now I pay attention to my AFR gauge and plan to lift under detonation
 
My advice:
1. Take the head to a machine shop and have them machine it the remove the marks and have them check out the valves and seats. If more than .060in is machined from the head, get a timing belt that's 1 tooth less.
2. Measure piston stick out. I've had b230 engines with pistons below deck, and pistons .003" above the deck. Get a HG that puts you in the .030-.038in squish range.
3. Then CC the chambers and then un-shroud the exhaust and intake to get the CC's where you want them for your final CR. The machine shop may be able to help with this.

Of note, Harlard is running his 16v turbo with a head that was a "little" beat up from detonation and a few forged pistons coming apart. He just smoothed the big divots out and sent it. So far at ~300whp and happy.

If I cant get the divots out I'll defiantly just get a new head, no since in running valves that cost 5 times more then a better head in one that's got hotspots and more prone to detonation.
 
These pictures show the divot / relief for the block-to-head oil passage (click for full size or see the original posts).


Does this imply that the head hasn't been surfaced before? I don't remember seeing this relief on machined heads.
 
These pictures show the divot / relief for the block-to-head oil passage (click for full size or see the original posts).


Does this imply that the head hasn't been surfaced before? I don't remember seeing this relief on machined heads.

Could just be stains from constant oil pressure against it? I'll see if I can just rub it off when measuring it tomorrow
 
The oil passage from block to head jogs over slightly -- your pics show that there's a teardrop shaped relief in both the block and head. If the head is surfaced down much, I think the teardrop in the head goes away (but the block teardrop remains for good oil flow).
 
The oil passage from block to head jogs over slightly -- your pics show that there's a teardrop shaped relief in both the block and head. If the head is surfaced down much, I think the teardrop in the head goes away (but the block teardrop remains for good oil flow).

Some reliefs are in the block, some the head. I just measured a head on the bench, and the oil relief is 2.5mm deep... FYI
 
The oil passage from block to head jogs over slightly -- your pics show that there's a teardrop shaped relief in both the block and head. If the head is surfaced down much, I think the teardrop in the head goes away (but the block teardrop remains for good oil flow).

I was looking at the wrong spot, I see what you mean now

Some reliefs are in the block, some the head. I just measured a head on the bench, and the oil relief is 2.5mm deep... FYI

With that deep an oil relief the teardrop shape isnt going to go away, but ill measure that too just for the hell of it
 
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Ehhh, You could push a shaved head a lot more than that :)
Sure, you can, but any material removed reduces it's ability to deal with heat and can likely make it easier to warp if situations aren't ideal. I don't know how much of a problem that actually is, but Thomas(RIP) was always a stickler about keeping these durable redblocks durable.

Lots of good info in his car/engine related galleries here, if you haven't seen this stuff yet: https://www.pbase.com/stealthfti
 
Seems a lot of trouble and expense to salvage something that's going to be compromised and is dirt cheap & readily available in the junkyards in much better condition.

Heck you could even get one off of a Turbo car that has SS exhaust valves....

But hey what do I know?

:e-shrug:
 
Heck you could even get one off of a Turbo car that has SS exhaust valves....

But hey what do I know?

:e-shrug:
I agree that the heads are cheap to get, but I don't agree that the turbo cars have SS exhaust valves... Come on Ken, you're forgetting things! The original exhaust valves in the turbo heads were sodium filled to help with the transfer of heat out of the valves.
 
I agree that the heads are cheap to get, but I don't agree that the turbo cars have SS exhaust valves... Come on Ken, you're forgetting things! The original exhaust valves in the turbo heads were sodium filled to help with the transfer of heat out of the valves.

They're not magnetic (well very slightly magnetic).... Which doesn't necessarily mean SS or not-SS.
 
I agree that the heads are cheap to get, but I don't agree that the turbo cars have SS exhaust valves... Come on Ken, you're forgetting things! The original exhaust valves in the turbo heads were sodium filled to help with the transfer of heat out of the valves.

You're right my bad, :oops: but as stated the fact remains that a JY head will be less than walking into a machine shop, or buying fancy butt valves.

Like more than lunch for two at the roach coach, but less than dinner for two if purchased on a sale day.

:cameron:
 
the fact remains that a JY head will be less than walking into a machine shop, or buying fancy butt valves.

Like more than lunch for two at the roach coach, but less than dinner for two if purchased on a sale day.

:cameron:
I do agree!
 
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