Hi
I have a EU spec 2g with a stock 2g 7bolt N/A 4G63 (which basically acts as a 4G64). I have the found a good deal on a 1G valve cover+head+intake+throttle body combo (all stock). I wanted to change the valve cover for a long time now, because it is cracked. The quiestion is, is this setup compatibile with a 7bolt 4g63? Does it come with any gains? If it just messes up my timing or idle, and nothing useful I will only go for the valve cover.

If your main interest is a swapped valve cover, you can do that without swapping the head, etc (assuming the n/a 4G63 you guys got was DOHC).

I don't know enough about the N/A 4G63 to say if the heads are easily swappable. There might be difference in deck heights or something that'd give you issues. Someone else will chime in.

You wouldn't want to put a 1g 6-bolt intake manifold on a 2g 7-bolt head; the port sizes don't match and it will cause a bunch of turbulence.

It is a DOHC, itt looks identical to the 4G63T I think the only difference is the compression ratio (apart from the turbo ).
I can buy the 1G cylinder head with the intake, so the whole top part of the engine would be swapped, still I'm worried about timing, I dont know if the 1g timing is identical to the 2g

Why would you want to swap the head and intake? It wouldn't make any more power.

That's what I was asking, I just saw some 2g people here with 1g intake in their cars and I got corious why could they do that. But I guess they did a whole engine swap

patman said:

That's what I was asking, I just saw some 2g people here with 1g intake in their cars and I got corious why could they do that. But I guess they did a whole engine swap

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With respect to turbocharged 4G63s, the heads can be interchanged with some machinework. The head studs are different diameters between the generations and so the holes in the head need to be enlarged for the head studs to fit through.

As far as the reason to do the swap, it mostly comes down to port size. Many people jumped to put a 1G head on a 2G block because the ports are much larger on the earlier head and manifold and the thinking was that the 1G head would flow better because of this. The reality isn't that clear cut because the flow through the two heads isn't as different as previously thought. The important thing for you to keep in mind, being naturally aspirated, is that Mitsubishi updated the 2G head with narrower ports in order to keep inlet velocity up and therefore help low and midrange torque. Switching to a 1G head might net you some more available flow on the top end, but without other mods you are unlikely to see any of that benefit while still seeing the downsides of the lower velocity on the 1G head and intake manifold. We're actually starting to see things go the opposite way, where 1G people are swapping to 2G heads for the higher velocity and more optimal flow angle.

Assuming that the N/A heads follow this same pattern, you would be better off keeping your 2G head if you're otherwise keeping it close to stock.

randman2011 said:

With respect to turbocharged 4G63s, the heads can be interchanged with some machinework. The head studs are different diameters between the generations and so the holes in the head need to be enlarged for the head studs to fit through.

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You're thinking about the other way around. He's has a 7 bolt. There is no machine work to be done when putting on a 6 bolt head.

As for the OP and the head swap. There will be no gains. If anything you might lose power from the lost velocity of going to larger ports because you are NA.

lasthope05 said:

You're thinking about the other way around. He's has a 7 bolt. There is no machine work to be done when putting on a 6 bolt head.

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I didn't specify which way was which because I wasn't sure. I had a feeling that it was the 6-bolt that used larger head studs. Thanks for affirming that.

Thanks for the help guys. Altough I have turboing in plans I will keep it stock for this summer, and will not waste my money on useless changes thanks to you

What about the 1g 7 bolt intake and or possible head swap as well.