help needed.

[vkberlina]

Ok, no more work or cost in doing a 308 over a 253. They are externally pretty much the same size.
Power wise in a VK a stock carbie 202 was 86kw where as the 5L was 121
VC 202 had 83kw and 4.2 had 100 for s ingle exhaust and 115 for a twin. Back in the Red motor days ie VB commodore a 202 was 66kw 4.2l was 87kw for single exhaust or 96 for a twin exhaust and a 5l 114 for a single and 125 for a twin.

As for port matching I dont think a genaral mechanic would be interested, possibly a head place might but they would probably want to do the whole head, it would require stripping and putting back together. If you have a die grinder and some time to spend on it I can supply info doing it yourself.

cheers
Scott

 

[Spilly]

i dont have a dremel grinder.. but i can get my hand on one so the info on doing it myself would be very handy...

 

[vkberlina]

You will need to buy a VRS kit comes with all gaskets new stem seals etc.

You need some thing a bit bigger than a little dremel, also use a carbide bit, you can use stone for finishing work if your first cut isnt neat.

You need to strip the head first removing all the valve gear, number all the valves, springs, retainers etc and put them back on in the same order. Also take note of how you remove the stem seals and when you reassemble the head install the new stem seals the same as the originals.

To check the ports you can carve a few pieces of wood something like pine is ok to check port sizings against both the inlet manifold, head then exhaust manifold & head ports.

Once you have opened the ports up you need to really really clean the head, make sure you some have any metal filings left in the head. I use a 60L drum cut long ways in half and scrub with deisel. Wear gloves and dont leave the deisel on your skin for a long time it will peal it off so scrub up well afterwards.
After its cleaned up wipe it down and start reassembly, depending how long its been since the head was done or if you mix up the valves you might want to repast in the valves. thats like a fine sanding paste you put ont he valve seat and spin the valve around to match both surfaces together.

When reinstalling the head make sure the the surface that comes in contact with the gasket is void of all old gasket and is completely oil free I use acrylic paint thinner to make sure its clean. Clean it under a good light to make sure there is no old gasket on it.

cheers
Scott