Hi....just a question about "cossie heads"... witch one, 2wd or 4wd, would be the best head to use, as Im thinking about getting it modified.

I have one of each, so Im trying to find out if I should use,.... the 2wd or 4wd head ??

Also if I could get some advice about cams...should I change both ..or as I have heard only the inlet cam... ?? And what type...bd 10-12 or ... ??

The car, 2wd Sapp Cos, with 4wd engine, L8 and so on, will be running greys, uprated T-34 and so on.

Please advice

 

4x4 head has better water cooling..

ports will be modified on either so its ok..

cams are a tricky subject..

If i were you i would get both meaured and go with the thickest

 

thanks rapidcossie

does anyone else have some info ?

 

As per Euan above - use the thickest head. If both are thin, sell them and start with a better head.

Cam choice will depend on lots of different factors, so talk to your tuner for his/her recommendations.

 

ok...so how thick should it be ..or not be ??

 

138.6 is a bit thin to start porting
139.2 is as new

 

ok and thaks...I'll have a look and see how the are and decide what to do.

 

I found that the 2wd is 138.8 and the 4wd is 138.9 ..... so almost the same...

As understand the above...it dosent matter witch head I choose .... correct ??

so about porting...can anybody explain roughly what that means ??

 

But to add to this the late type 2wd head has the same cooling/holes as a 4x4 head

so thickness is the key(thicker the better)

A 2wd head(unskimmed) will reduce comp on a 4x4 bottom end(std 4x4 pistons)
A 4x4 head std will have a std comp ratio if unskimmed !!!!!

2wd comp chambers are bigger than 4x4 ones (got there in the end)

 

As for cams it deoends on what you want Big power or torque

Tricky subject std cams are good for around 410 bhp ish

 

so actually I should keep the std cams as my aim is around 400 bhp.....?

 

how do I find out if it is a late type 2wd head ..?

And does that mean that the 2wd head will be the best to use..?

 

There is a car on here runs 406 bhp on greys a T34.63 and BD 10's on std comp aswell

I was told a long time ago that 10's were not that good and your low down suffered and they was not much different to std cams...

The choice is yours cams and headwork and pistons if going to 14's= big money OR a really good pair of rear tyres to get the most power to the ground

you would be better of going for a coilpack conversion so you can then run bigger plug gaps for a better burn,emisions,and running and more mpg

 

ok....So what you are saying, is that I should leave the head and cams std, and run my std 4wd engine (st 3 at the moment), put on the greys + a bit more boost and maybe a MSD CL chip setup, and if there is money left, to go for the coilpack setup...

 

That's will be good, i've been told with an MSD chip you will deffo see 380 bhp more depending how good your turbo cooler etc is

this is what i'm hoping for as mine runs a escos chargecooler(no room for a 500 type in the tina )

i will post some pics up of the three different Heads up soon for ya

Paul

 

looking forward to that ..

 

Here are the different Heads
3dr Head with large water jackets (exhaust side)1st pic

Late saff 2wd Head smaller water jackets 2nd pic

4x4 Head same as above but with no turbo hanger and revised front cam caps, and oil supply to turbo on head as mentioned before this head has smaller comp chambers but also gives better torque 3rd pic

 

super....I'll have a look as soon as i'm home tomorrow.

so the one's to use is the late 2wd or the 4wd head.

thanks

 

My choice whould be a good 2wd Late one then next the 4x4 one depends on how thick they are

let us know when u decide

 

ok ...with a little luck I'll be back tomorrow...

 

Hi,

Sorry for hijack.
Very good info and pics.

Another thing that i noticied is the difference between port surface plan exhaust. On 4wd head, it's bigger than 2wd, to increase heating transfert between head and exhaust manifold.



Regards

Claude

 

Nice one claude

This is only found on the early heads 3dr and early saff will post up the cast numbers later for the heads

 

hi ..just checked it..and it seems to be a early type 2wd head I have .. like on the first (top) pic of the heads. hmmm.I was hoping that it was the late type as I could then send it out , and then just "make a quick swap" when it was back....now I will have to take my car of the road til its done..... I wish I had the ŁŁŁ now so it could be done while it is winter as it is off the road until april ...

 

Shame that Tom looks like its the 4x4 head then

saying that many people still run early heads i think even jenspeed still uses them depends on you!!!!

Good luck

 

ok ... I'll find out

Thanks for your help