10 replies to this topic

[craigr91]

Referring back to my topic

http://www.theminifo...-3#entry2860465

Seen a 12g940 for sale which but its has 36/29 valves where has standard '940 heads have 33/29?... will this head be compatible with my 998 setup?

Thanks, Craig

[Sam Walters]

Two types of head. One large valve one small valve.

Both will work. But in your application id try and get as much meat between the valves as possible.

Thus the small valve might be better. But in the grand scheme of things. It makes next to no difference so just bang on whatever you can get your mits on. 

 

[craigr91]

And I can even use the big valve head if I go 1275 too yeah?

[Sam Walters]

And I can even use the big valve head if I go 1275 too yeah?

you can use the small valve head or the large valve. the 12g940 casting is a large bore head.

[John H]

Personally I would stick with a small valve head if you are going 998 turbo.

[craigr91]

So hard as I am trying to build and buy in the option I can easily go 1275? Which I am strongly thinking, 1275 block, big valve head, gearbox with ratio to suit me and keep all turbo stuff the same?

Decisions!! I'm buying incase I can't get hold of a 1275 but I'm buying invade I do haha :)

[jaydee]

A 998 turbo will be cheaper than a fully modded NA 1275, fast and reliable.

Edited by jaydee, 31 July 2013 - 08:34 AM.

[craigr91]

I'm defo going turbo, wether 998 turbo or 1275 turbo is my next thought :/

But in essence shall I get the head to go in my 998? With the possibility that it will go on a 1275 turbo?

Cheers

[holmesy]

go 998, the best engine i ever had, 1275's are money pits im building my old 998 into a turbo to replace my 1310 full out engine

[craigr91]

I want lots of power but I'd like to say 'yeah, it's only a little 998 and I think 100bhp shall do me for now ;) now I just need know what head to buy, wether it'll be too much work for the 940 large bore ... Cheers

[jaydee]

A 998 will be better imho, unless you're looking for the ultimate power..

As Sam said, the 940 small valve head will be best

Turbo phil on here does cylinder head work for a fair price, have a chat with him