295 head advise

[DanRodd]

Hi all,
Yesterday i struck lucky and managed to get a complete HS4 carb on a mini manifold,a very nice,crack tested 295 head with new valves,double springs etc and a few other bits.

What i would like to know is can i just fit the head straight onto my 1098 engine?would i need the standard 1098 headgasket?
should i skim it?the chap i got it off who used to race minis said he wouldnt reccomend skimming it,and it should be fine as is.

I know i will need to change the needle in the carb,so thats not a worry.

Would the double springs be ok to use on a minor?or should i fit minor springs?

would be grateful for any tips

[bmcecosse]

If the head has not already been skimmed - then it will need 80 thou removing. So - you need to measure the thickness of the head - they all start at 2.750" - so any less than that is what has already been removed! This may be why he said don't skim it - if skimmed too far - it breaks through into an oil passage, and the deck becomes too thin anyway! Use the double springs if you want to do super high revs and wear out the valve train! Since 1098 engines should never be revved beyond 6000 - I suggest removing the inner springs and just use the outers. They will take you to 6000 ok! Check what needle is in the carb and report back.

[DanRodd]

thanks bmc,the measuring details are something that is much appreciated,is that the distance between the headgasket face and where the rocker cover goes on?
i was thinking that the double springs would be too much for the standard drive train,and as its been sat in a garage for 20yrs or so i wanted to grind the valves in just to be sure so will take them out.

[bmcecosse]

Yes -overall thickness from face to face.

[DanRodd]

right ive measured it and have a measurement of 68mm,or 2.677",so its obviously been skimmed,question is(as im not too hot on my conversions!) how many thou have been taken off from standard?

[DanRodd]

excellent,just worked out that the head has had about 75thou taken off,so is pretty much ready to stick straight on

[bmcecosse]

Yes if accurate measurement - that's 73 thou off - which is near enough. Grind in the valves as well as you can - and consider fitting the later 'top hat' oil seals to the stems. The original O ring seals are next to useless! And yes -you use a standard 1098 head gasket - and NO gasket cement!!! Just a smear of grease on the perfectly clean block and head. Tighten to 44 ft lbf in stages - set inlets to 12 thou, and exhausts to 15 thou. Start it - warm it up - then retorque and re-set the valve gaps. Have you found the needle in the carb yet ? It will go much better if you can find an MG Metro alloy inlet manifold (or one of it's many copies) which will need an HIF38 carb, although you could easily make an adapter plate to use your HS4.
Edited to correct 'senior moment' posting of 73mm instead of 73 thou - oh dear...........

[PSL184]

that's 73 mm off

Best to get about 10 head gaskets as well then

[DanRodd]

Thanks for that,
measurement done with a vernier gauge.dead on 68mm= 73thou taken off
although the vavles have recently been done,very clean etc,i shall be taking them out to remove the second springs so will change the seals then(one of the reasons why i want to take the old head off anyway)
wouldnt use gasket gunk on a headgasket anyway,so no worries there!

havent stripped the carb yet,but think i might do that in the next hour or so,so will report back.Believe all the parts were off a 998 cooper engine

[bmcecosse]

Why you say that ???? PSL ?

[bmcecosse]

998 Cooper had this head ok (as did MG1100 and 1098 Spridgets)- but all with twin HS2 SUs on hopeless inlet manifold!

[PSL184]

Read the quote Roy - 73mm "off"

[bmcecosse]

Thanks PSL. "You must have a lot of time on your hands to be worrying about other peoples' posts etc etc " to quote a recent example from this forum.......... Just joking - well spotted - dangers of posting after a few glasses of wine! Now corrected - with explanation!

[PSL184]

Hahaha - I just didn't want anyone to go in with an hacksaw and take 73mm off