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Do anyone know if the pinzguar712 have a cylinder head gasket ?

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They do not

Is there a problem that you think removing the head will solve or just ready for a overhaul?

If you do tear this motor down, there's a number of procedures to follow
if you want it to go back together again properly. For one, keep all the parts
together associated with cylinder #1, 2, 3, and 4. The heads need to be
either float ground at the machine shop to get a good tight fit to the cylinder
or hand lapped -- IMHO hand lapping is best, very little material is removed
and it's a whale of a lot less expensive.

btw

the engine design is based upon petrol with 87 octane. In Europe we only get 95 octane fuel, thus an increase of the compression rate can be considered.
I had 1,5 mm removed from the cylinder head bottom surface when I decided to redo the heads. The result was noticeable.
Bear in mind that you have to modify all mounting holes for the engine cover parts.
Also replace all rubber gaskets for the pushrod housings and the oil return pipe.

Hotzenplotz wrote:btw
I had 1,5 mm removed from the cylinder head bottom surface when I decided to redo the heads. The result was noticeable.
Bear in mind that you have to modify all mounting holes for the engine cover parts.

I've been considering this exact thing. Did you have to alter the pushrods to compensate for the shorter distance also?

Doesn't Jim's (Goatwerks) 2.7 liter piston set also increase the compression ratio? I think it would without requiring modifications of the engine tin holes etc. as well.

Anyone know?

Yes, both the ROSS and ARIAS piston options for the 2.7L
increase compression. The conversion is aimed at Torque
improvement at the low end, so Compression and Cam profile
are the biggest kickers.

I find my 2.7i to be like driving a normal car/truck up to 80kph
After that it gets louder and slower acceleration
It’s a blast to be honest

I had 1,5 mm removed from the cylinder head bottom surface when I decided to redo the heads. ... Did you have to alter the pushrods to compensate for the shorter distance also?

I would think that 1.5mm difference could be accommodated by the rocker adjusters.
From what I think I remember that I heard, the Arias pistons that are in my 2.7l engine bumped up the compression ratio just a bit, from like 7.0 to 7.5:1 compression? But I really do not know the exact amount. With the EFI system I can adjust fuel ratios and ignition timing across the rpm and vacuum ranges to prevent knocking, I run just cheap low octane fuels.

Jim,

You might want to do a compression test if you are under 8:1 compression ratio.
You should be well over 120psi/cylinder, more in the range of 130+. The 2.7L
conversion gets most of it's punch from compression and Cam lobe profile. The
capacity increase is actually less than 2.7L with Jim's ARIAS pistons, I think more
in the 2.6 to 2.65 range -- leaving some jug wall left for future boring is needed.
So capacity increase is actually a part of the whole but more of a secondary.

If your ratio is where I suspect it is you may be leaving Torque on the table. You
may be able to advance a bit more aggressively but then need a bit higher Octane
to prevent pre-ignition. I run 91 and pretty aggressive advance, tuned up at
John's shop at Outfront Racing -- we saw a huge boost in Torque as seen in the
pulls pushing the advance.

Jim L. recently did a compression check, getting in the 130-140 psi range across all four cylinders. So I guess that would be in the ~9:1 compression ratio (130/140 divided by 14.7). But I didn't think Jim upped the compression much; checking, I find that the stock engine was 7.5:1. Again, I'm not saying that I definitively know any of these values but only that I thought I remembered that Jim said the increase in compression was only about point five greater than stock (at least in my engine). I have had the ignition advanced to the point of knocking (on low octane fuel) but backing off did not seem to reduce the power. I doubt that using premium will allow any significant improvement in power, regardless of the advance. My opinion is that these relatively low compressions (whether that be 7.5:1 or 9.0:1) are not high enough to take advantage of a high advance and premium fuel. Honestly, I do not believe I would find enough of an improvement to justify the cost of premium even if there was improvement to be found. This is just my opinion and expectation.

At one time I did have the exact "new" bore and stock stroke values; I remember that these gave a real displacement of only 2.62 liters (not a true 2.7 liter) but I really don't think the jugs have enough meat to be bored out to a true 2.7 liter. The numbers are ALWAYS rounded up by every manufacturer, so I just call it 2.7.

Jimm391730 wrote:I would think that 1.5mm difference could be accommodated by the rocker adjusters.

Not to hijack the thread or belabor the point, but I've seen some valvetrain damage on VWs where the pushrods geometry is altered that amount. Valve stems can wear differently. I was planning to shim the rockers 1.5mm to compensate, but thought I'd see his solution.

Apologies, I have been offline some time due to surgery.
Removing 2 mm from the cylinder head (or anywhere else) is still within the adjustment range of the valves.

I have tested the compression; all 4 cylinders around 10; before it was 7,8 to 8

no issues so far

This sounds good. I did the math with 1mm and calculated about 9:1 CR. Thank you. Have a good recovery.