Need help on big bore 2.0 project. Heads.

[Dansvan]

Hello all. I am building a 69t 2.0 motor for my kit car. The engine came in the car and upon tear down appears to be all original except for a pair of CRANE P296 cams. No joke. Weird. Anyway I am installing a set of old school EMPI 87.5mm big bore cylinders and pistons designed for the 2.0. This kit was designed with the idea that you would enlarge the 90 degree cut around the 2.0 combustion chamber to accommodate the new barrels. I want to use later style 2.4/2.7 heads to take advantage of their larger ports and valves. Is there a method of sealing these heads to these barrels?

2.0 head


2.7 head


old and new barrels.


I was curious if an aluminum or copper ring around the outside of the barrel ridge would work. I could have the 2.7 heads welded up and machined down but was hoping for a simpler solution.

[larrym]

suggest you look for a cheaper solution using mated parts

- the later heads are sealed with a CE ring - the early heads use a flat gasket

- never the twain shall meet

since you say you can afford the welding & machining to reconfigure the heads - you can easily afford the alternative of getting matching used p&c's for those late heads & pay to machine the case to accept the larger jugs

,

[Dansvan]

I agree. However- I am constantly reading how if building a high performance 2.0 the heads should be replaced with later model 2.2 or 2.4 heads. Page 89 of Waynes book- how to rebuild and modify Porche '911 engines says this. I read it on here. How do you do it?

[Steve@Rennsport]

Originally Posted by Dansvan

I want to use later style 2.4/2.7 heads to take advantage of their larger ports and valves. Is there a method of sealing these heads to these barrels?

I was curious if an aluminum or copper ring around the outside of the barrel ridge would work. I could have the 2.7 heads welded up and machined down but was hoping for a simpler solution.

This can be done, however its not cheap to do since the later heads must be welded and machined for CE rings. Its well worth the effort to get a FAR better cylinder head design.