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6 bolt block & 7 bolt head

22K views 19 replies 9 participants last post by  NCDirtrider249  
#1 ·
Hey everyone, so I've looked around and searched but I cannot find anything solid of what I need to do. When I put my ACT2600 clutch in my car, well it crankwalked. :( But, I got a JDM Evo 6 bolt block, but I am going to re-use my 7 bolt head. What all do I need to do in order to swap my head onto my new block? Besides the obvious, head gasket, studs, etc. I already bought a new set of ARP 6 bolt head studs, and a CAS.
 
#2 ·
The head needs to have the holes for the head studs machined out to 12 mm to accept the 6 bolt head studs. Other than that it's a pretty straight forward swap. Just make sure if you order a new clutch/flywheel that you don't order it for the chassis but rather the engine.
 
#4 ·
I believe no 6 bolt block leaves no place for a crank sensor. Your 95 has a slightly different setup than my 97 had but I THINK you will still have to run a 1G CAS like I did. Clutches are the same for FWD and AWD turbo cars but the flywheel is different. Search 6 bolt swaps since that is what you are doing alot of them are 6 bolt blocks with 7 blot heads. Also check vfaqs.
 
#7 ·
95 head won't need drilled for studs.

use 1g CAS you will need the crank trigger unless you go with kiggly's unit.

95 needs firing order and injector order swapped.
 
#12 ·
You have 3 wires going into the COP. I can't remember if it's 2 hots and a ground or 2 grounds and a hot. Either way the 2 trigger wires need to be swapped.
 
#11 ·
Not all heads, 95's did not need enlarged, I should know, I put a 95 head on one of the first street driven 6 bolt 2g's back in 2001. Later heads yes, what's funny is the 95 head under the 4bolt thermostat housing is a drilled and tapped 3 bolt 1g thermostat housing bolt pattern. You can bolt either of them to a 95 head.
 
#14 ·
The 96+ heads I've tried to put on 6 bolts don't fit at all the stud doesn't pass through them.

Oil flowing around the stud into the head? The oil galleys in the block are a fixed hole they don't go into any galleys, and once you lock down the stud the combination of lube/threads/pressure wouldn't allow any oil to get up past them anyway.
 
#15 · (Edited)
The oil feed to the head goes around the stud on the passenger side, exhaust side of the engine. If you look at a block, the oil galley to the head is next to the stud on the passenger front of the engine. It goes through this indentation in the head, around the stud, and into the head. To tight of a clearance will starve the head, and turbo if fed from the head, for oil.
Image



More info can be found here.
http://www.dsmtuners.com/forums/newbie-forum/341028-4g63t-head-oil-port-mod.html
 
#16 ·
That's crazy. Thanks for the link to the good read.
 
#17 ·
Well 1 stud makes more sense, you made it sound like they all did that.

What I find interesting is not only did I put 50k miles on that motor but in the current configuration the A1 head studs are not tapered like the factory studs and are quite a tight fit but oil pressure measured in the head was so high the 3g lifters were causing the valves to stay open at high rpms to the point I needed to put the kiggly HLA in to regulate it.
 
#20 ·
Because it'd be cheaper. I could re-use the head on my car, and not have to worry about buying a new head, intake manifold and throttle body. But, my plan is to have a motor completely built and put together so when it comes time to swap the motors out, I won't have to do anything extra, in theory.