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Discussion Starter · #1 ·
We're now offering a stage 3 head in addition to our stage 1 and 2 heads.

If you're running a bore much bigger than stock (88mm or larger), it is recommended to go with our new stage 3 setup, which includes deshrouding the valve area.

Notice the stock combustion chamber on the left vs the ported and deshrouded chamber on the right. The outside corners of the valves have been opened up, allowing more air to enter around that corner.

Also notice the area near the seat on the intake valve towards the center.



Flowbench results:

 

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Pretty damn good gains in my opinion. But you can see how well the 4b11 head flows stock, so this really should only apply to a full build with a turbo that can flow to make a solid difference.

My tuner said valves always make power, like 10-15 so I for sure went with bigger valves on my build and the head was off so porting/polished that. Probably not to the extent of this one but good enough to clean it all up and get it smooth.

Thank you for actually given hard results though! Looks like a great option for a well prepped head. Nice work dino.
 

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Discussion Starter · #5 ·
Pretty damn good gains in my opinion.
Absolutely.

But you can see how well the 4b11 head flows stock, so this really should only apply to a full build with a turbo that can flow to make a solid difference.
Agreed. The stock 4b11 head is great. Unless you're going with a built motor, just doing the head probably isn't worth it for most.

My tuner said valves always make power, like 10-15 so I for sure went with bigger valves on my build and the head was off so porting/polished that. Probably not to the extent of this one but good enough to clean it all up and get it smooth.
Yeah, and we can add valves to the above work. a +1mm valve will likely add 10cfm to the numbers we've already made. That being said, if you're doing larger valves, a deshroud is even more important.

Thank you for actually given hard results though! Looks like a great option for a well prepped head. Nice work dino.
:thumbup:
 

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Im guessing this is what I will be getting done in the future. This with bigger valves. Looks like a pretty good upgrade from the chart you posted. Good work
 

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Discussion Starter · #10 ·
Well, think of a shroud as an enclosure around something. In regards to a combustion chamber, the valves are naturally shrouded by the outer walls of the combustion chamber. So we make those walls less steep (since we are going with a larger bore) by removing some of the material there.

Deshrouding basically it means that you're removing material around something (in this case it's the area around the corner of the valves) that would be considered a shroud.

If you study the photo I posted, look in the outer corners of the combustion chamber on the right and compare it to the left. See all of the material that's missing instead of there being an abrupt wall there?
 

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I didn't deshroud anything on my 2.2L overbore, not that I know of anyway. We originally did the headwork for my 2.0L so I can almost guarantee its not done. Wish I would've known that a month ago when my head was off, oh well.
 

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Good lord, what happened to that thing?

If you go with a deshroud and new valves, it will get rid of most of the damage. the rest we could weld and recut.

If you're serious about it, let me know.
yea i brought it to a shop and they said pretty much the same thing. How reliable would welding and all that be. I'm scared a piece would break off and cause damage again. As for what happend... piece of the #1 piston broke off, got caught in the valve, ripped it apart and the base of the valve jammed in there 90* sideways. Can you PM the price of how much it would cost to repair and pretty much PnP the rest of the head.
 

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yea i brought it to a shop and they said pretty much the same thing. How reliable would welding and all that be. I'm scared a piece would break off and cause damage again. As for what happend... piece of the #1 piston broke off, got caught in the valve, ripped it apart and the base of the valve jammed in there 90* sideways. Can you PM the price of how much it would cost to repair and pretty much PnP the rest of the head.
Spend 1k and get a new head man, not to take away any work from Dino, but don't fart around with something that screwed up, you don't want to nuke another motor :)
 

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Discussion Starter · #16 ·
I didn't deshroud anything on my 2.2L overbore, not that I know of anyway. We originally did the headwork for my 2.0L so I can almost guarantee its not done. Wish I would've known that a month ago when my head was off, oh well.
Yeah, it happens. If and when you have the head off again, we can always go over it for you.
 

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Spend 1k and get a new head man, not to take away any work from Dino, but don't fart around with something that screwed up, you don't want to nuke another motor :)
was thinking that same thing. Was just curious what dino thought..lol. I wish i had the money right now to grab the head from hollywood.
 

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Discussion Starter · #19 ·
yea i brought it to a shop and they said pretty much the same thing. How reliable would welding and all that be. I'm scared a piece would break off and cause damage again.
It would be very reliable, so long as the weld was good. If you had us do it, we'd make sure it was done right.

As for what happend... piece of the #1 piston broke off, got caught in the valve, ripped it apart and the base of the valve jammed in there 90* sideways.
Oh, awesome.

Can you PM the price of how much it would cost to repair and pretty much PnP the rest of the head.
Sure - did you want new stock valves, used stock valves, or aftermarket valves?
 
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