Hey guys, just wondering if you run a decomp plate do you have to run a head gasket on both sides of it!?...

I pulled the head off turbo A14 motor with a decomp plate and just one head gasket on the head side. The motor has run succesfully for awhile, I thought you had to run two gaskets.

Cheers

Got any pics?

Hylomar or similar would have been used to seal the plate to the cast iron block.

I got told to use copper head gasket cement. I used VHT coppper head gasket cement.

Jeff Taylor recommends O-ringing the block as well.

Yes thats the stuff I ahve used to seal everything I can around manifold etc... Recommended by rallycar.

Heres a pic of the Decomp plate... I was worried it may be a spacer, if they had take loads of the head or the block because it was warped. (unlikey). It is about 1.5mm thick. I have left it out should raise comp slighty maybe to 8.3? was 8.0:1

i said "loc-tite copper max"

i pressume the other is a similar product... xcept it doesn't carry my endoresment

what compression are you chasing? 8.1:1? say hello terrible off boost performance, hope it hits boost early

what wrong with 9-9.5? you arnt gonna boost above 10-12psi are you?

i wouldnt bother o-ringing unless chasing high boost either

Yeah, I was thinking 9:1 would be okay until I went and saw a engine builder mate. Saw the book figures on boost Vs Compression. WAs pretty scay how high it spikes on compression just with 10psi on 9:1 compression, BUT its doesnt take in alot of factors with motors its just genarl idea. But if you have run 9:1 and that sort of boost I cant see too many issuses, thats why I wont use the decomp plate and run it at 9:1.

Hey Rally, What is your current setup!?.. You havent been updating much. What is the most reliable setup you have achieved so far?. ( i know you have mentioned tune being the biggest issue)

I used these head shims on my turbo setups with no problems. You only use 1 head gasket on top of the shim and use Hylomar sprayon the block and shim as phunk said. If this engine was running well before with the shim, I'd be inclined to use it again to avoid any problems with pinging.

Yes you make a good point Harry. It is intercooled too So that should help take the risk down. I would like to run it at 9:1. I may give it ago and keep a close eye on it.