L24's , L31's and heads

[Gee]

Started up the car after work the other day and the head sounded like it has something broken in it. With the sound of cash registers ringing in my ears, I wonder if I could get some help/information regarding a rebuild.

The thing is, at some stage in the future I would like to build an L31. I don't have the room to put the original block aside at the moment so I will have to stick with the L24 for the time being. As I might as well do a head rebuild properly, I don't want to throw money at something which is suitable for the L24 and not an L31. Basically, what I'm asking is - is there an appropriate head which I can build up, put on the L24 block and then later use on an L31?

Help!!

[zguitar71]

The problem will be the compression ratio. If you build a head for a 3.1 to give you 10.5:1 compression the 2.4 would have very low compression with that same head. The valves used to get proper breathing on a 3.1 will hit the sides of the L24 block unless you eyebrow the cylinders (requires puilling the enigine and tearing it down). I think you should save your pennies and build the 3.1 without compromisses. To use a head that works on the 2.4 you would loose lots of power on the 3.1. I would go with a P90 head from a ZX turbo for the 3.1. Get the one with mechanical lifters not the hydraulic lifters (later models (`83 I think)). The P90 head has very straight intake and exaust ports, the exaust are square like the older heads (like your 240 head) and the compression would be around 9.5-10.5:1 depending on how you set the head up. You could make alot of power for a street car with that head. Really you could use any head for a 3.1 but I think the P90 is the best for a street car because it was made for a turbo so the head was designed to flow air better than the other heads and it is said to have the most efficient burn design or quench. But no matter what, you will have to modify (port, polish, cam, ect..) any head you use to get big power out of a 3.1 so it is going to cost you money either way but that is how you get 300+ HP out of the 3.1 and still be very streetable.

[e_racer1999]

my recommendation would be to build an E88... wait on a valve job and a big cam until you do the 3.1L...