17 replies to this topic

[shashora]

Hi im getting my 1100 engine rebuilt at the moment and he said if i want it to go well i should go for the 1275 head which is the 12g295, do you all concur?
But after looking for some ive found that u can get the 12g295 off a 998... Is there any difference between this on the 1275 and 998??
Also i have found that on some 1275 it is not actually 12g295 imprinted but 12g940. Am i spinning out or are there 2 releases for the 1275 and what one is the better??

Also where can i find this number cause i have a 998 lying in my garage and im trying to find it and i was told near the thermostat and ive taken off the thermostat housing and i find a short 4 digit number which cant be it???

Please help, much appreciated as always
Thanks
Adam

[Pie]

The 12G940 was the 1275 head.
The 12G295 was a 998cooper and if i remember rightly they were a better flowing head. The 295 also had bigger valves, 1.21 as to the standard 998 heads 1.09.

This topic link might help you a bit.

Basically though, for your engine build pocket the block so the valves done meet the block and stick on a 1275 head and a nice cam, should make a bit of a difference.

[ginigwunkle]

what sepc are you getting the 1100 built too?

[partsguy1]

12G295 is a 998 Cooper Head, nice head, (people will tell you that they are worth loads, but they are not) I have at least two in my parts pile. 12G940 is a 1275 Head. The Casting number is under the Rocker Cover, beneath the Rocker Gear. A 12G295 head will be all you want on a 1098cc. The 12G940 Head would require pocketing the block, if the block or head have been skimmed. I really don't feel that there would be much gain in using the 1275 head.
Terry

[shashora]

what sepc are you getting the 1100 built too?

Thanks for the help lads but as for what spec im leaving it up to the head engine machinist. He recommended me to go for this and im thinking he will build the rest to suit? Is there anything u can recommend from experience?

[shashora]

The Casting number is under the Rocker Cover, beneath the Rocker Gear. A 12G295 head will be all you want on a 1098cc.
Terry

Hey Terry mate ive taken off the rocker cover how is it that you take off the rocker gear??
To seperate the top end from the bottom end is it just removing the bolts around the top or much more difficult than that?
Cheers mate

[shashora]

Hi just taken off all the bolts in the right order according to the leyland workshop book. so this is where i am now.




So thats all i can figure to take off althoguh the head is still not coming off, i have taken off the exhaust and intake manifold...
But so any ideas guys??? im pretty lost? Also still any ideas on how to get to the engine number??
Cheers adam

[partsguy1]

Interesting Head you have there, looks like a Canadian Spec 998. The ports on the front (with the hex headed plugs in them) would be used to pump air into the combustion chambers, it was an early effort to improve emissions.
The Rocker Gear should just pop off, you may have to prise it up a little if it has been sitting for a bit. There is also one Head Stud nut you missed by the Thermo Housing. When you get the Rocker Gear off pull the Push Rods out, keep them in order so they go back in the same hole, I usually poke them through a piece of cardboard and number them 1-8. Oh, and twist them as you pull up, helps to separate them from the Cam Followers.

Once you have that done, whack the Head on either end with a Dead Blow Hammer or a Rubber Mallet............. that might help break the Head Gasket bond.

Terry

[shashora]

Interesting Head you have there, looks like a Canadian Spec 998. The ports on the front (with the hex headed plugs in them) would be used to pump air into the combustion chambers, it was an early effort to improve emissions.
The Rocker Gear should just pop off, you may have to prise it up a little if it has been sitting for a bit. There is also one Head Stud nut you missed by the Thermo Housing. When you get the Rocker Gear off pull the Push Rods out, keep them in order so they go back in the same hole, I usually poke them through a piece of cardboard and number them 1-8. Oh, and twist them as you pull up, helps to separate them from the Cam Followers.

Once you have that done, whack the Head on either end with a Dead Blow Hammer or a Rubber Mallet............. that might help break the Head Gasket bond.

Terry

Wow i cant believe u can tell all that by just that picture...
But thats so weird i missed that head stud cause i was looking at it thinking where did it go must of been looking at the wrong hole. Anyway ill take that out.
Is there anything i can read up on removing the rocker gear and pushrods?
Cause im quite lost with those parts

Cheers for your help Terry!

[wolfys_mini]

lever them off, not rocket science, it will just pop off

[shashora]

lever them off, not rocket science, it will just pop off

Hahah cheers mate.
so i can just pop it off without removing the rocker gear or push rods? cause dont know what they are exactly and where there located??

[Pie]

what sepc are you getting the 1100 built too?

Thanks for the help lads but as for what spec im leaving it up to the head engine machinist. He recommended me to go for this and im thinking he will build the rest to suit? Is there anything u can recommend from experience?

Pocket the block, stick on a 12G940 head and put in a decent cam. JetBLICK got 64bhp from doing that. I dont know of any thouus running a 295 head with that spec. Unless the head is race spec, and even then with a decent cam your going to need a few more upgrades.

[shashora]

Ok ive got the head off... But i can see any numbers on the head other than on the top left...
Does anyone know if this is a head number.... ( ECAM 4004) ???

Here is what i can see ..


Is this where i should b looking on the top or am i missing somethign???

Thanks guys

[miniboo]

that wont have what people know as a standard head number as it is one of the emission/smog reducing heads(yeah right) no good basically so have a look for a 12g295 head or go for the 12940 head and pocketed block.

I have a 12g295 head but i think postage from the USA might be a killer.

[shashora]

Hi just curious to weather i can use a different cam with the 12g295? Is the 12g295 still a push rod setup? From what it looks lkie it must be but from what ive heard off a mate is that a push rod is not able to be modified with new cams??

Cheers adam