[racecardaddy]

Car in question is an '85 P-type. I have read I should use a HKS metal head gasket (mhg) for the turbo swap I am about to undertake. I have a fresh head (valve job, new cams, springs, no bump in compression from machining, etc.), and am using a stock low miles bottom end. I plan to run 6psi boost, or so.
So far my parts list reads like this;
CT26, manifold (modified to fit p/s bolt) and ic from an 88 turbo
stock shortened downpipe from same 88 turbo
HKS Powerflow air filter
90deg oil filter relocator kit
SAFC
RRFPR 10/1 ratio
oil cooler
Plan to get Rabidchimp oil line kit
2.5" downpipe to tail pipe using Magnaflow mufler

I plan to make ic piping from comercial food service grade stainless mandrel bent and straight sections, available locally cheap. What am I leaving out. I have the articles from Jim King and others, so I feel prepaired. I run a auto repair shop, and am a decent mechanic.

Thanks for your replies.

Keith

 

[SilverMk2]

The HKS HG should work fine. You can also use the Greddy one as well. Just make sure you have the deck surface flat and smooth enough so that the HG will seal well. Otherwise you're just asking to do the job again.

 

[3000cc MK2]

The HKS HG should work fine. You can also use the Greddy one as well. Just make sure you have the deck surface flat and smooth enough so that the HG will seal well. Otherwise you're just asking to do the job again.

I second the motion to that.... there are now 3 manufactures making MHG for the MK3... and it all work fine to our motor just finding a good machinist to do the job right is the hard part... well the cheapest now in the market is the TitanMotorsports MHG.... check out www.suprasport.com for those TMS,HKS,Greddy gasket for cost

 

[82TURBOSUPRA]

HKS is the only one to get,hasn't blown in 15 years of boost.

 

[82Spearco]

I have the 2mm Bead type HKS MHG. It cost me $200 USD. This is slightly thicker than stock and will lower your compression a little. If you ever plan to turn up the boost on that 9.2:1 compression '85, I suggest getting the 2mm. By the way, boost is an addiction, once you have it, you want more. I run 7 psi, and can't wait to turn it up a little.

 

[Racefiend]

stock headgasket will work fine for 6psi, if you're looking to save some $$$. However, the MHG is always extra insurance. Both Mike and I used a Greddy MHG and both had disappointing results. I'd suggest the HKS.

Christian

 

[racecardaddy]

Do I need to prepair the block/ head a certain way?

I plan on just installing the "new" head when I do this, not pulling the engine and decking the block. What advice on MHG installation?

Thanks,

Keith

 

[SilverMk2]

If you aren't going to resurface the block I think you might want to reconsider using the metal gasket. Too many folks throw on a MHGs on Mk3s with out the proper head/block work and end up having another BHG. I would read the FAQ that Reg wrote on the SOGI/SONIC site to get the basic idea. Basically you need a very flat surface on both side and the surface has to be fairly smooth (around 16 RMS IIRC). A 16 finish is a fine machine finish that not really "mirror" smooth but has very fine machining marks that are basically unnoticeable if you run your hand over. Most engine machine shops are lucky to get into the 32 RMS range. This is why most people go thru the trouble of lapping the head and block even after the head and block surface have been thru the machine shop.

 

[82TURBOSUPRA]

Use a 2 mm HKS metal head gasket if you are going to run 10 psi boost or more (you will).have the correct finish put on head like SilverMk2 said.
I would get APR studs for head. Get top of block perfectly clean, scrape clean with razor blade do not nick block, no sanding on block, if block has any dark spots in metal or rust GET THE BLOCKED DECKED.And you don't want to ever run lean with those stock cast pistons.
I have accidentally hit 30+ psi and never blown head gasket and the Arias pistons and carillo rods don't hurt.
.