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head questions

waltesefalcon

Yoda
Platinum
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Is there any good reason a head off a 1500 wouldn't work on a 1300? I can't think of any.
 
I happen to have a 1500 head on my 1300 engine so I can tell you that it 100% will work.

HOWEVER, you will wind up with something like 1:6 compression (no pinging!) to get a slightly more "normal" compression ratio the head will have to be machined a bit.

First of all you will have to find out exactly how large the chamber is now. This is called cc'ing it and you basically need a sheet of plexiglass with a hole and a burett tube to find out exactly what the volume of the chamber is now.

Next you will need a cr ratio calculator. Lots of those on the web to figure out how much smaller to make the chamber.

finally you need a machine shop to start machining the head and measuring the chamber until enough material has been removed. I needed to remove ~1mm from the head.

I aimed for a CR of about 1:8.5
 
I have done this swap and you must remove 125 thou off the head to get the 1300 size chamber.the advantages are hardened seats and larger valves in the 1500 head. Obviously its best to CC the chamber for the exact ratio desired, for the driving you want to do.
MD(mad dog)
 
That's a big difference between 1mm and 0.125"...1mm ~ 0.040".
 
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