doing head, 54mm zongshen

[china boy788]

the spring compresser

thats what i want to remove, tryed the screw diver and wouldnt go???

more pics uploading of ports if you still wanna c them?

 

[sean01]

underneath that little spring wire wrapped around the seal, thats where you lift from. but if they have gone hard just get them off any way you can without kill the valve stem...

yep i made a similar gizmo the other day to use with a g clamp, but mine is just an adapter..

yeah post the pic of the ports it will be good to see a before and after shot of them

 

[china boy788]

ok sweet, didnt wanna try and pull the right bit off and screw the head,

justing posting that up for any one else who wants to make one, its a 16mm spark plug socket, cut and welded to a F clamp

yer i will if photobucket will hurry up

and will die grinder bits fit into a drill chuck??, if so thats wat ill get

 

[china boy788]

intake

exhust

 

[sean01]

and will die grinder bits fit into a drill chuck??

yes they will

 

[china boy788]

ok sweet, ill get them, also my valves are 2 diff size?? ones 65mm and other 66mm
guy from akunar said theres 3 things to do,

Well the valve sizes you mention measure up identical to the std ones we have that can repalce yours. a mm or 2 here and there is not a great deal. In fact we are having an all new lot of valves arriving next week with most of the ones designed for use in very large heads all about 1-2mm longer and equal length in/ex. Comon practise to take up the loss of length due to a smaller stomach cam or slightly longer or very stiff springs.

i jst emailed back saying what one do you recomment for good power output plus having a strong motor that just kept going, so not blowing after a month

 

[sean01]

ok, i hate to say it but i totally Disagree with most he has told you...

the valves HAVE to be the same lenght..ie from valve tip to collet groove and from collet groove to valve head..
if you use longer valves you are going to change the rocker geometry and possibly cause increased cam and valve tip wear...
for longer valves to work you would also need longer rockers..
to explain why...

ok on a closed valve you want the rocker tip(bit that you adjust clearance) to be somewhere around number 3 in that pic.
and on full valve opening you want the rocker tip to be at number 1 in the pic...

add a longer valve and the rocker tip will be closer to the middle meaning on full valve lift the rocker tip is going to be close to the edge of the valve....
in a push rod engine this is recified by using longer pushrods, but we have a cam there instead so we cant add anything unless we spray weld it and get it hardened again...lets put that in the too hard basket and overkill...

ok next. if we raise the height of the collet groove then we have to add the raised amount to under the spring to correct the spring tension on the valve seat...
you may be thinking but its only 1mm...1mm is enough to loose 10-20lbs seat pressure...and these engines dont have alot to start with....
also if you raise the collet groove but retain the total valve length then you run the risk of the retainer hitting the rocker...

ok, im starting to sound like a tafe teacher now.....im guessing you get the picture...

keep everything standard length and only change the springs.
if your valves dont look too bad just lap them back in. if there fooked then buy the exact valves that came out of it...


hmmm my head herts...^^^ too much going on i think

 

[china boy788]

ok so ill email and and ask for new valves that are the same size? as b4??? one bigger then the other??? he also said that with the tight springs he has that i should only put his outer ones in?? and if i get valve boucning then put inners in?? does that sound right??

if it comes to worst case then ill put old ones in, but would like new ones for the motor anyways

 

[china boy788]

oohh and before it goes for the bath tommorm. is there any thing under the valves steam seal to remove???

 

[sean01]

ok to work out with the springs you need to know the installed height of the valves...

you say you have a set of vernier calipers...

assemble the inlet valve back in the head but dont put the spring back in. just the bottom shim the retainer and collets..
now with the verniers measure the distance under the retainer to the spring shim...hold the valve shut too...

now with that measurement give it to akunar and he should be able to test the springs to see what the seat pressure is with and without the inner spring...

now also if you have a vice. you can use that installed height to measure if your springs are good enough...
make sure you write down that measurement. now take the lift of the cam plus 1mm off that measurement and write down that too...
so 6.7mm+1mm then subtract that from the installed height and that will leave you with the measurement that the springs need to be or exceed on full valve lift.
now put the springs in the vice and close the vice till the spring coil binds...dont force it tho.. now measure that and see what it is...

post the measurements and ill double check them...

getting pretty complicated hey....

no nothing under the valve seal

 

[sean01]

also what is the size of your valves?

 

[china boy788]

ok ill do the first bit, but unsure of the second thing?? and i dont have a vice, and still has std cam atm too

 

[china boy788]

intake 27 by 66
exhust 23 by 65

 

[sean01]

ok well as far as the valves go, i thought from the way you said he was saying the valves he has are alot longer(couple of mm's)......
.5mm isnt going to change sht all.....so this set from him will do the job AKV27236550 (3rd set down)

just remember to measure the length of the cam to tell akunar

 

[china boy788]

yer there the onces he said,

and yer when he emails back ill tell him its the 75mm one

 

[sean01]

yeah im pretty sure its the one he has advertised as the ducar 140. also are you getting all your gaskets from him too....

good way to bump the compression up is to use his head gaskets...if possible...just ask him

 

[china boy788]

ooh yer not sure wat he got it as but he sent me the number in email.
yer geting all gaskets from him,, would jst the normal one bump up compression?? or wood i need two??

 

[china boy788]

from base of the shim to top of retainer and collets is about 23mm too jst got it then

 

[sean01]

the thinner the gasket the more comp, but check your piston doesnt come out the bore at all

 

[DvDRip]

damn this is getting really technical, I thought it was just a case of buy the springs and cam and chuck it all in