Vr4 4g63t head lifting on high boost

Hello Andre

On my previous setup I had a gsr lancer with a vr4 engine and I had 550hp to the 4 wheels. I still have this engine as it's going in my new car which will be rwd. When I ran the 1/4 mile at wsid my head started lifting on high boost. I have bought ARP L19s and will be installing them. I will be removing the head to check it out. I have a few questions.

1: Should I replace head gasket?

2: What things would I need to check when I remove the head?

3:Which head gasket would you recommend? I saw you used the hks gasket on the 2j in the practical engine course. Would you recommend the same for the 4g63s? I have multi shim in it now not shore what brand was installed by my previous engine builder.

4: How do I measure the thickness of the gasket on the engine now? Is there specs stamped on the gaskets or do I measure it with verniers? The reason I'm asking is the hks come in 1.2 and 1.6 thicknesses

kind regards

Steven

1. If the head has lifted then yes, you will need to replace the head gasket.

2. You will want to confirm the block surface and cylinder head surface is 100% flat. If the engine has been running for a while with the head gasket leaking then it's also possible that the head may go soft so a hardness test is worthwhile in the areas the head gasket has been leaking.

3. In our own 4G63 drag engines I tended to use the HKS stopper-type gasket in 1.2 mm thickness. At high boost levels though I also combined this with a stainless o-ring in the block to help improve head gasket seal.

4. Since the MLS gaskets don't really compress when clamped, you should be able to get pretty accurate measurements with a set of vernier callipers or a mic.

Thanks for the good info Andre really appreciate. You know any good machinist from Sydney even though your in New Zealand.

Sorry mate I'm not up to speed with Australian based machinists.

Andre can i remove the head with all internals still attached. I know timing belt needs to be removed.

Yes, the design of the 4G63 head allows you to remove it with the cams and rockers still installed. Make sure you time the engine to TDC #1 before removing.

Sorry for the dumb question Andre but how do i know if im at top dead centre? Timing belt has already been removed too.