different valves, dished/flat

[gttjames]

elliot off here has just dropped me round his c1j head to rebuild. And i noticed 1 head has dished valves, the other has flat. Which ones are original or which should we be using?

Thanks

[Ian S]

Dished valves? Got a photo?

I think the originals are flat.

[markg]

Just had a look at a couple of spare heads I have here. On both heads the larger of the two valves is dished.

[gardner51]

Was told when I bought it that had different valves,


Ellz

[allanr5gtt]

they might be 1mm bigger?

[turbo ted]

the flat valves will be out of a metro turbo or mini;)

[gttjames]

the flat valves will be out of a metro turbo or mini;)

oh right cheers ted. Whats the main reason for using flat valves then as oppossed to oe?

And il get some pics tomorrow just to show difference

[Ian S]

One would be cost?

I seem to recall that a mini valve were £6 and a Williams Clio valve were £50 and were interchangeable.

[gttjames]

One would be cost?

I seem to recall that a mini valve were £6 and a Williams Clio valve were £50 and were interchangeable.

oh right i see, i didnt know if it was for performance reasons.

I got some pics anyway. standard valve on right, valve in middle is different, less material flatter on back, dished on face side, and all different collets for tthe different valves
http://i15.photobucket.com/albums/a371/sr50james/cylinderheadddd005.jpg

again standard valve on right, other one in middle
http://i15.photobucket.com/albums/a371/sr50james/cylinderheadddd004.jpg
http://i15.photobucket.com/albums/a371/sr50james/cylinderheadddd001.jpg

[gttjames]

Iv striped the replacement head down, it measures 73.4 so standard thickness - good place to start. All the collets look fine and not damaged, as with everything else. Reason its been stripped is to fit the piper valve springs. While im doing this is there anything else to do. I was just going to re lap all the valves and build it up with the new piper springs. And general oponion i get is to run these without valve stem oil seals yer? As most had lifted anyway why buy new to fit for them to lift?

cheers

[michael tierney]

i'd go with the seals(not that dear)tap them on with a socket and they should stay on

[GTphil]

If the motor the head is destined for is going to be revved then I wouldn't bother with the valve stem seals, it might puff a blue cloud on a hot start but thats about it as long as the guides are ok.

I take my c1j to 7k regularly and sometimes beyond, when I took my rocker cover off to re-set the tappets every one of my valve stem seals has lifted, my bros engine was even worse we found bits of valve stem seal down the bottom of the push rods towards the cam followers! Pretty much every stem seal was obliterated :eek:

[THE MASTER]

again standard valve on right, other one in middle
http://i15.photobucket.com/albums/a371/sr50james/cylinderheadddd004.jpg

the valve on the left is not a c1j valve if you notice the collet groves . all gtt's/c1j valves have twin groves

[gttjames]

If the motor the head is destined for is going to be revved then I wouldn't bother with the valve stem seals, it might puff a blue cloud on a hot start but thats about it as long as the guides are ok.

I take my c1j to 7k regularly and sometimes beyond, when I took my rocker cover off to re-set the tappets every one of my valve stem seals has lifted, my bros engine was even worse we found bits of valve stem seal down the bottom of the push rods towards the cam followers! Pretty much every stem seal was obliterated :eek:

thats what im thinking. The engine has a 285 cam and t28 turbo and will be running 22-24psi if fueling allows, so with the 285 it will be revving quite high. Iv got 4 heads here in total, and only 1 of them the followers look intact still - but that was my old head and wasnt revved hard and max boost of 13psi. Yer reckon we'l leave followers then.

But toher than that, clean it up, re lap all valves, re fit with piper springs and its good to go.

[gttjames]

again standard valve on right, other one in middle
http://i15.photobucket.com/albums/a371/sr50james/cylinderheadddd004.jpg

the valve on the left is not a c1j valve if you notice the collet groves . all gtt's/c1j valves have twin groves

yer thats what iv noticed, allt he standard ones have 2 groves, cheers

[markey b]

Iv striped the replacement head down, it measures 73.4 so standard thickness - good place to start. All the collets look fine and not damaged, as with everything else. Reason its been stripped is to fit the piper valve springs. While im doing this is there anything else to do. I was just going to re lap all the valves and build it up with the new piper springs. And general oponion i get is to run these without valve stem oil seals yer? As most had lifted anyway why buy new to fit for them to lift?

cheers

i dont run stem seals, apart from a little puff it was never an issue :)

[THE MASTER]

i could be wrong but as far as i can remember the gtt's/c1j exhaust valves are somthing like sodium filled

if your not gonna use valve stem seal your valve guides need to be in good nik with little to no wear. a floppy fit will smoke to much..

im using two springs on my valves. i dont know wot they are off but if found a smaller valve spring that fits inside a std spring . my rev counter only goes to 8,000rpm and i often pass the 8,000:upyours2: ive neaver dropped a valve and ive neaver popped out a push rod :coffee:

[gttjames]

i could be wrong but as far as i can remember the gtt's/c1j exhaust valves are somthing like sodium filled

if your not gonna use valve stem seal your valve guides need to be in good nik with little to no wear. a floppy fit will smoke to much..

im using two springs on my valves. i dont know wot they are off but if found a smaller valve spring that fits inside a std spring . my rev counter only goes to 8,000rpm and i often pass the 8,000:upyours2: ive neaver dropped a valve and ive neaver popped out a push rod :coffee:

smaller spring inside your oe spring, sounds very custom. Well il make sure they valves arnt floppy in the guides, if they are then i guess no choice but to run the seals. But if all ok il build it up without them. Cheers

[gttjames]

on further inspection, have noticed the old head that smashed a valve has ctm 422 stamped on top where rocker cover would seal it. ctm head then. Valve guides arnt as pressed into the head as far as oe ones, then where the oe ones protrude into the valve bore bit, the ctm ones dont, and have been ground off to make it smooth. Looks like it had alot of work

[gttjames]

i could be wrong but as far as i can remember the gtt's/c1j exhaust valves are somthing like sodium filled

if your not gonna use valve stem seal your valve guides need to be in good nik with little to no wear. a floppy fit will smoke to much..

im using two springs on my valves. i dont know wot they are off but if found a smaller valve spring that fits inside a std spring . my rev counter only goes to 8,000rpm and i often pass the 8,000:upyours2: ive neaver dropped a valve and ive neaver popped out a push rod :coffee:

Iv checked the valves in the valve guides. How much movement is to much? They arnt mega floppy, but there is movement side to side?

[gttjames]

well looks like itl be safer to fit the seals, to stop them from lifting and coming loose is there anything special to do when fitting?

Also iv been told by sammo that he had good results fitting some from a vauxhall???

[Ian S]

If you'd like, CTM can lower the spring seats and fit longer firmer new springs to go with the 285 cam lift of about 11mm, or whatever. They did that with mine.

They have a tool to measure the spring rate of each spring.

Years ago I got I got from Sparkie some new stem seals I now don't need and will sell. Not sure if they're Vauxhall.

[gttjames]

james5 remembered and pm'd me what there from

http://www.rtoc.org/boards/showthread.php?t=20616&highlight=valve+stem+seals

[James5]

james5 remembered and pm'd me what there from

http://www.rtoc.org/boards/showthread.php?t=20616&highlight=valve+stem+seals


Think Robbie aka turbo Ted used to use them on his C1J back in the day aswell:agree:

[THE MASTER]

Iv checked the valves in the valve guides. How much movement is to much? They arnt mega floppy, but there is movement side to side?
bit like a birds pussy realy ... to loos and its gonna flopp around . to tight and..... ile stop there.... cant explan it realy ..years of building :hump::banned::banned::banned::banned::banned::ban ned:

[rs250nut]

oh right cheers ted. Whats the main reason for using flat valves then as oppossed to oe?

And il get some pics tomorrow just to show difference

Flat valves will make the combustion chamber smaller there for raising the static compression ratio.

[Scoff]

Those valves with 3 collet rings are Metro turbo valves (larger inlet)