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hi guys,

as some of you know ive recently smashed up a valve or 2..

i got my self a cheap new head in great nick... off to be machined, ported and polished and once over while its out...

questions i have tho...

are the cas marking i had on the old head now irrelevant?

if yes, how do i go about finding the new spot to bolt him up to...

and when i put the head back on... line up the 3 points (crank and 2 cam wheels) and drop it on.. and get a belt on ASAP??!!

when putting the exhaust, intake manis, and head back on... do i tighten center out wards, on all 3? and do i tighten bit by bit.. or all center bolts tight as needed,,, and next?

thanx :action-smiley-069:

Edited by chef_stagea
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hi guys,

as some of you know ive recently smashed up a valve or 2..

i got my self a cheap new head in great nick... off to be machined, ported and polished and once over while its out...

questions i have tho...

are the cas marking i had on the old head now irrelevant?

if yes, how do i go about finding the new spot to bolt him up to...

and when i put the head back on... line up the 3 points (crank and 2 cam wheels) and drop it on.. and get a belt on ASAP??!!

when putting the exhaust, intake manis, and head back on... do i tighten center out wards, on all 3? and do i tighten bit by bit.. or all center bolts tight as needed,,, and next?

thanx :action-smiley-069:

Your CAS marking will indeed be different. When putting the CAS back on, centre it with the 3 bolts, so you have the same play each way. Then get a timing light and adjust as necessary when its running.

Before putting head back on, set the crank to TDC and turn the cams on the head to their respective timing marks.

Bolt the head up to torque specs from the inside out, in a zig-zag formation. The head gasket packaging should have specs on it. You'll need to go thru this 3 times, getting tighter as you go and torquing to the max spec on the last one.

Same with the manifolds.

Put the cam belt on. Once the head is on, do not rotate any engine components until the belt is on to keep the timing uniform.

Good luck.

as ruby said getting the crank to TDC , and setting the cams to their timing marks is the way to go.

it could be done using the marks u have made, but if u get the belt out by a couple notches the pistons will be meeting valves again and you will be back where u started

ok... thanx guys..

well is it maybe a safer option to get my current head fixed, using parts from the new one?? or is it the same with the cas... center it then adjust as needed?

any one gota legit torque wrench i could borrow for a sunday?? probly not going to be for a few weeks yet..

ive got an r34 manual yes...

it says cyl head bolt

unit (Nm)

1) 29

2)98

3)0

4)25-34

5)95 - 100 degrees (angle tightening)

wtf does this mean :S it says next to it tighten seperatly in several times...

bight, tighten, nothing, loosenish, then swing it 95 degrees :S lol....

cyl head sub bolt? whats this?? 9.0 - 12 NM

Edited by chef_stagea

Just a wild suggestion here.... you made a rather costly error once doing this. Now you've got to fork out a fair bit of cash to fix the problem, maybe it's best to get a professional to put it back together. You'd hate to be going through this drama all over again

ok... thanx guys..

well is it maybe a safer option to get my current head fixed, using parts from the new one?? or is it the same with the cas... center it then adjust as needed?

any one gota legit torque wrench i could borrow for a sunday?? probly not going to be for a few weeks yet..

ive got an r34 manual yes...

it says cyl head bolt

unit (Nm)

1) 29

2)98

3)0

4)25-34

5)95 - 100 degrees (angle tightening)

wtf does this mean :S it says next to it tighten seperatly in several times...

bight, tighten, nothing, loosenish, then swing it 95 degrees :S lol....

cyl head sub bolt? whats this?? 9.0 - 12 NM

Adam, as Heslo said, you can't afford to get any of this shit wrong.......unless you know exactly how to define torque sequences (amongst many other things), please leave it to a pro......spend a little now, save a shitload later.

Adam, as Heslo said, you can't afford to get any of this shit wrong.......unless you know exactly how to define torque sequences (amongst many other things), please leave it to a pro......spend a little now, save a shitload later.

Always my mantra

Another thing, no one will lend out a good quality torque wrench, they are a high calibrated tool, cost an arm and a leg and can easily be stuffed up in the wrong hands.

There are some cheap shit brands around that someone may lend you but I'd never let one of those anywhere near my engine......I'd do a better job going by feel (when my elbow clicks) :rolleyes:

What are you worried about the timing marks for your CAS for as you should use a timing light for the timing. Setting up the timing is easiest thing that you have ahead of you. The timing marks on the cam gear backing plate are factory markings and it won't matter what head you have on there they will match up with the cam gears.

As a double check you can count the teeth between the marks.

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