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Brad_03tj
19-09-2012, 05:20 PM
OK I have been searching AMC for the last couple of nights. Have not found the information I was looking for. (N)

I have a set of heads ( 6g74 ) that I will be putting RPW stage 1 cams in after a port and polish.
Now the info I am looking for. :D:D

How much can the heads be machined as one has some deep scoring marks on the head gasket side. I know it will increase compression but is there heaps of room with the stock internals. eg. valves hitting pistons.
6g75 Verada
19-09-2012, 08:35 PM
I believe the limit for machining the head surface is 0.2mm - total resurfacing depth of both cylinder head and cylinder
block (according to the service manual). I'd suggest looking in the manual and confirming before undertaking any machining :)
MadMax
19-09-2012, 08:42 PM
Take it to a machine shop and let them see. If too deep it can be filled in with weld and resurfaced.
Dave TJ
19-09-2012, 08:48 PM
That is the factory limit you can take more, there is plenty of valve to piston clearance. The cam timing will retard as material is removed and the lower intake manifold might not fit so well I wouldn't go past 1.00mm.

Cheers Dave
kurt
20-09-2012, 10:38 AM
OK I have been searching AMC for the last couple of nights. Have not found the information I was looking for. (N)

I have a set of heads ( 6g74 ) that I will be putting RPW stage 1 cams in after a port and polish.
Now the info I am looking for. :D:D

How much can the heads be machined as one has some deep scoring marks on the head gasket side. I know it will increase compression but is there heaps of room with the stock internals. eg. valves hitting pistons.


Save your money and get the 3.8l conversion u won't get much power from stage 1 cams
..GONE..
20-09-2012, 10:48 AM
Save your money and get the 3.8l conversion u won't get much power from stage 1 cams

I believe he's already got the cams..

SuFz :ninja:
Brad_03tj
20-09-2012, 03:40 PM
What he said...../\......
Archie_80
20-09-2012, 03:59 PM
what about ralliart heads? i have some i bought and never installed, are they higher compression and ported?
Brad_03tj
20-09-2012, 04:53 PM
Well I have heads and cams, so it is just time and some machining and some porting and some gaskets and it should be good to go.
HaydenVRX
20-09-2012, 05:00 PM
what about ralliart heads? i have some i bought and never installed, are they higher compression and ported?

Not worth the trouble, only gains a few kw.