Hello everyone, wondering if anyone can clear up a question I have..

I was under the impression one could not swap the N/A 1.6 cylinder head with the Supercharged 1.6 head?

I'm looking at picking up a 2002 Cooper S with a cracked head (coolant in oil). A local parts recycling guy is saying the heads are interchangeable.. Is that true?


If so, I think I'm going to pick it up today for pretty cheap. Would make a fun project for my nephew and I!

 

I do not have first hand experience. My inference is from reading the Bentley manual. The difference between R50 and R53 head is that latter has forged intake and exhaust valves, which is better in every measure. The exhaust valves of the latter is sodium filled - again better. R50 being atmospheric has lower compression and I again, infer it is the difference in the piston design. So if I am in your position, I will tend to believe you can use a R53 head. I would quiz your parts recycling guy a bit more and trust his advice.

 

Compression for the R50 is 10.6:1 whereas the R53 is 8.3:1 according to the owners manual. My understanding is that the heads are identical. The valves are made differently but identical in size. The cam, oddly, is also identical in lift/duration as well. Probably made differently though. I am looing at making my R50 a project and my initial investigation, which at this time is minimal and ---
I AM STILL CHECKING ON THIS TO VERIFY IF IT IS TRUE---
is showing that they are essentially identical. Going from an R53 on to an R50, again, if my initial information is correct, should be just fine. Going the other way probably would cause catastrophic failure issues due to the values not being made the same way.

 

The head casting is the same. But you need to replace the valves with the S valves as they are sodium filled and the non S aren't. So you would burn them if run on an S.

Also if buying a used head it's best to go ahead and rebuild it before install as it will likely need guides, seals, and a valve job. We keep all the parts on hand to do so.

 

Absolutely awesome, y'all are great!


I'm leaning towards picking up a remanufactured Cooper S head, a bit more pricey at $689 shipped, but it would be nice getting a rebuilt unit with new valves/etc, with a warranty and not have to mess around with taking chances on a new/unknown head...

 

2nd, or whatever the number is, on being able to use the head from an S on a justa. My understanding is the only changes in heads were that the JCW had larger exhaust ports. Also a big 2nd on having any head you buy at this point worked over. The head can be in great condition, but it's WELL worth $250 to replace the guides, get a valve job, and get everything cleaned. Consider it insurance on not having to do the head again.

Also - swapping heads is a relatively easy task. It can definitely be performed in a day. You'll be unbolting multiple small parts, though, so organization is key. Keep some cardboard and parts bins around to keep track of everything. It'll make putting it all back together MUCH easier.