Cylinder head gasket thickness after machined

[Jspc_dhx]

Good afternoon. First of all, thank you very much for all your help and the community.

Well, after disassembling my engine for the culprit piston No. 4 (80 psi). We decided to use forged pistons and forged connecting rods. Then as one thing leads to another I decided to change main bearings. I sent my block and cylinder head to the grinding workshop... we decided to machining the cylinder head at 0.07mm ( with a marmol polish ) and the block at 0.05 mm... the grinding workshop told me to use the original size gasket (1.250mm) I Seeing that the oversize adds 0.30+ but I only subtracted 0.12 in total... so what do I do? Do I use the original or the oversized one?
my car.
Flow max + at 25 psi ( 650 whp )

RegardS!

 

[JohnDaviz]

I would say don´t worry.

You slightly decrease compression ratio with the thicker gasket. That will not harm your performance so much and you can counter react with probably slightly more timing due to the lower ratio.

 

[Jspc_dhx]

I would say don´t worry.

You slightly decrease compression ratio with the thicker gasket. That will not harm your performance so much and you can counter react with probably slightly more timing due to the lower ratio.

Do you think I can use the original thickness head gasket (1215 mm)? In total we removed 0.130 (between milling the block and the cylinder head)... I have saved 2 genuine gaskets of original thickness (1215)... Thank you for your response!

 

[JohnDaviz]

This way you will increase the compression ratio. This may or may not lead into increased timing corrections and more difficult tuning.

Please only take my thoughts as food for your decision making. I am no expert by any means but i personally would not increase the compression ratio further. But this really is just my personal opinion.