Tony Turbo

Bonjourno,

Anybody have any idea on how to spot if a CVH head is an RST one, or if there are any differences at all?

Thanks

morcheen

early ones had sodium filled valves but later didn't,i'm not sure of the change over date but someone will know.

Hardeep_Singh

port shapes! can't remember which way round it is the rst are either squarish or round and the xr3i's are the other and obviously sodium filled valves but i don't think you can tell the difference of that just by looking at them.

Hardeep.

NEO™®©

rst's have round combustion chambers not sure about the others

xr4x4rs

iTrader: (5)

theres no way to tell what the difference is

the only difference is the cam and sodium filled exhaust valves

other than that thhere both exactly the same

efi are different though

NEO™®©

im sure that the rst has dome shaped combustion chambers in the heads and the non turbo version had a heart shaped chamber ie the lean burn 1.4 etc

Ginge !

ok the erst cams and the xr3i cams are the same profile !!!!, i know as i got a ford cam with both listed in it , the timing on a erst pully wheel is the difference aopart from that there the same, the domes on all the 1.6cvh heads are the same ! as there the same head, the lean burn heads ( mk5 cfi i think they was, not too sure though) have heart shape domes, think karl says there better for lowing ect and his top heads are used with em ut thats for karl to discuss as i know fook all about em )

the soduim filled valves are a S1 turbo thing, they was a crap idea and actually cause increased wear rather than decreased wear like there was ment to so frod scrapped that idea on the S2

so in short a xr3i head is the same as a erst head, now thats also the same on a frst head and a xr2i head too ( and the efi 1.6 engine cvh's too )

oh and the ports are all D shapes unless its ported then there round, but im sure that bit ya already know

NEO™®©

ah righty well i know for a fact that mk4 1.4 lean burn heads are heart shaped as i broke one a while ago lol
heres a pic of my rst head when i did head gasket if that helps lol

Ginge !

didnt know the mk4;s had a cfi engine, but then ive never cared about em to check

just like when i as asked to stick a dump valve on a scooby and looked at the engine bay, i closed the bonnet as it never looked like a engine i seen before and closed the bonnet as i didnt wanna know about em

NEO™®©

Tony Turbo

Riiiiight, thanks for those mixed opinions there lol

Keep 'em coming

adamS2RST

Tony,

We had a similar discussion here, https://passionford.com/forum/viewto...318&highlight= I know these are EFI heads but possibly the mfi are based on the same principle....I for one am not sure....

DazC

iTrader: (1)

The S1 head is the same casting as the RS1600i which means round exhaust ports......The S1 has sodium filled nimonic valves which was meant to aid cooling of the valve itself.

The S2 head is the usual D shapped ports IIRC.

I don't know if there is any difference in air flow between the 2.

Damo V

so a S2 head is the same as an xr head, which are the same as all "D" ported heads yeah.....???????

Also, whats a 30 thousand mile excellent original unskimmed Bare unmollested S2 head worth (for porting etc)

Ginge !

20quid as its a xr3i head

aint heads 400 quid from fords ???

Rick

Daz is correct with the ports - no diff in flow really either. The RST and 3i heads have hemi ports, the later "lean burn" heads have heart shaped combustion chambers - found on non injection cars. Both can be worked to good results, but the heart shaped head will cost u much more, as there is a lot more work.

Damo V

No,read the question again mate, I didnt ask the price of an XR head.....

I have 2 heads mate, one is defo an XR3i head, history unknown the other will be an immaculate low mileage S2 head (if I can find it)

CabrioTurbo

They still only go for £20
moon milage or 20k they are worth fuck all as standard as they are 10 a penny.

Damo V

so a moon mileage head which has say..... been skimmed twice, is worth the same as a lowmileage unskimmed item??? Doubt it.....

Tony Turbo

£25 then

vroooom ptssssh

ask philM