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K-jet head build for NA

Dropping the 398 off tomorrow morning. I'm asking for a quote for crack repair and seat replacement. If it's not too bad i'll do that and have the correct seats installed for the larger valves, along with a valve job and 60 thou taken off.

By the way, where could I source seats for these valves? Would anything off say, summit, that has the right OD work? I don't think I need anything super special for NA.

Also while i'm in there, where does the BCP need to be welded up to be suitable for high boost on a 96mm bore? This part is just a curiosity.
 
They said the crack wasn't terminal.

They did not like the idea of 60 thou off of it, at all. I sent them the camshaft specs for the K cam, the springs, valves, and the volvo standard engine service manual/spec pdf.
 
They said the crack wasn't terminal.

They did not like the idea of 60 thou off of it, at all. I sent them the camshaft specs for the K cam, the springs, valves, and the volvo standard engine service manual/spec pdf.
Haha, yes, it's well over what Volvo recommends removing. Just tell them you aren't expecting them to warranty it and that the Swedes take more than that off the head with regularity, sometimes literally twice that amount off.
 
They want new guides and (exhaust) seats installed for the 46/38mm valves, is that normal?
They also want a seal on each of the valves, when volvo only puts them on the intakes?
 
530 decked 2.6 mm here, Still going strong
More info, please? Feel free to update your other thread I splurged a bunch of info in.
They want new guides and (exhaust) seats installed for the 46/38mm valves, is that normal?
They also want a seal on each of the valves, when volvo only puts them on the intakes?
One of my machine shops would likely recommend the same things, yes. Robert doesn't like seals on the exhausts. I don't know what Erland thinks, but the two machine shops I normally deal with do all 8 valve seals now, from my experience. The guides are probably worn out, and your machine shop might just feel more comfortable with new seats for whatever reason.

Are they opening up the throats of the ports to make the valves actually worth installing instead of creating a larger restriction, too?
 
They want new guides and (exhaust) seats installed for the 46/38mm valves, is that normal?
They also want a seal on each of the valves, when volvo only puts them on the intakes?

Replacing the guides is pretty common, especially if the new OS valves are stainless steel. You can not use a cast-iron guide with a stainless valve. It must be a bronze guide or a bronze liner in the cast-iron guide.
The shop may also want to replace them if the tooling they use is extremely sensitive to valve guide wear. Some is much more so than others.

You do not need to have larger seats installed, but you will want to have the ID of the current seats opened up to ~ 86% of valve diameter. The OEM exhaust and intake seats are extremely high quality, and unless they're replacing them with HD seats, it won't be as good.

Also, tell the machine shop that valve stem protrusion is very very important and sensitive on these heads. If the valve seats are cut too deep, you cannot get the stem height corrected properly.

Lastly, tell them to put the smallest "top cut" on the valve seat. The deeper/larger this is, the deeper the valve will sit. If the valve ends up sitting to deep, you will need new seats and possibly new valves if they tried to correct it.


More info, please? Feel free to update your other thread I splurged a bunch of info in.
One of my machine shops would likely recommend the same things, yes. Robert doesn't like seals on the exhausts. I don't know what Erland thinks, but the two machine shops I normally deal with do all 8 valve seals now, from my experience. The guides are probably worn out, and your machine shop might just feel more comfortable with new seats for whatever reason.

Are they opening up the throats of the ports to make the valves actually worth installing instead of creating a larger restriction, too?

By design, the bucket blocks a lot of oil that would be on the stem. These are not V8 engines with rocker arms, where the stem can be splashed or submerged in oil.

I just don't see a need for them on the exhaust side. Even 200k mile turbo motors are not burning oil past the exhaust guide. On a street NA engine, I'm not opposed to using them with a bronze guide though. On a race engine or hot-turbo engine, I like to leave them out. Never a complaint or issue.
 
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Ok so had a bit of a phone discussion yesterday to clarify exactly what they/I want.
*The guides were "passable" but they recommended new bronze ones for the stainless valves anyway
*It is the intake seat that is too small apparently. I asked if they could make it work with the stock ones but they claim it's not possible. They will be opening up the seats and bowl and doing the short turn radius on both ports.

ETA early next week. I might ask them to do a little valve de-shrouding too, would that be worth it? Anything else I should ask for?
 
I might ask them to do a little valve de-shrouding too, would that be worth it?
If you have the funds, yes! Sorry for the delay, I had a response started a while back then got too busy to finish it. Before I lost any more time I figured I'd just say YES! Even with stock sized valves there's a restriction to flow. I'll see if I can finish my other post later with a link or two. Or, just search unshrouding valves and read what pops up. Or see my post in another related thread that I might be thinking of... There are three or four threads about NA performance and heads right now.
 
What headgasket are you guys running and what is your SCR you’ve calculated? Piston deck height? I can’t remember if you guys are running less timing than stock, as you’re still on the K cam, but that 2.5mm off the head seems like a lot assuming you are running thinner than a stock HG and just the K cam. I know it’s working well for you, though! :)

We use the Cometic 0.036", on this block the pistons protrude 0.004". Static compression ratio calculates to 10.9:1. Looking at the dynamic, there's room for more. We use a timing curve based on the B23E distributor, and have not fooled with it. We have the pin mod done for the EZ116K, but altering timing with it showed zero result. At first we thought that the chamber design was not conducive to these changes, but in reflection, we're not certain that the mod works under WOT conditions. Curve adjustment will be on the list when we go back to the dyno in the Spring.
 
We use the Cometic 0.036", on this block the pistons protrude 0.004". Static compression ratio calculates to 10.9:1. Looking at the dynamic, there's room for more. We use a timing curve based on the B23E distributor, and have not fooled with it. We have the pin mod done for the EZ116K, but altering timing with it showed zero result. At first we thought that the chamber design was not conducive to these changes, but in reflection, we're not certain that the mod works under WOT conditions. Curve adjustment will be on the list when we go back to the dyno in the Spring.
Sounds good. Your combustion chambers are basically stock, right(44.5cc volume after 0.103"/2.6mm off)?

That's approximately the same compression we were running with our ENEM K13 cam when we made 157whp/160wtrq(uncorrected) with a flat torque curve.

I am not sure the pin mod for the EZK does anything either. I messed with it 13 years:-)wtf:) ago or so on the dyno and saw no change, either. It could just be that we aren't too far off for ignition timing, too.

In any case, with your compression and the K cam, you might even be ok with less ignition timing. Time will tell. Any plans to remove the head and shave more? :)
 
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One step at a time, big boy! Gotta get my $xxxx header installed and tuned up. I pick it up from the welder Saturday, I'll post a couple pics.

Man I hope it does something other than take 15 lbs off the nose.

After that we can do a little more shave, a little more intake valve, a little more cam, and see what happens.
 
:cool:

I also hope that the header isn't designed for your exact current setup when you have plans to one day take it to a higher level with the additional shave, intake valve and cam. Excited for pictures and specs, though! :)
 




Deck height is 144.6mm so they took excactly 1.5mm off as i'd asked :)
Cylinder 1: 45.4cc
Cylinder 2: 45.6cc
Cylinder 3: 45.6cc
Cylinder 4: 45.2cc

Also, yesterday I got a shipping notification for my 0.036 head gasket. Should be here friday.:-D
 
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:cool:

I also hope that the header isn't designed for your exact current setup when you have plans to one day take it to a higher level with the additional shave, intake valve and cam. Excited for pictures and specs, though! :)

It is. That said, as it's primarily based on cam specs, as long as we don't make gross changes to duration and overlap figures, there will still be some effect.

Also, couldn't pick it up that weekend as New Hampshire went on the Mass do not travel list the night before I was supposed to go up, so there it sits.

esmth: You getting that head flowed? It might help with future decision making.
 
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