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right can someone one ok this. fitted degree wheel to the crank. fitted dial gauge to cylinder no 1 and rotated till found tdc by measuring the amount of degrees at full lift and halving. then rotated round to 110 degrees after tdc and found maximum lift on the inlet cam. then round to 110 degrees before tdc and found maximum lift on exhaust cam. then belted and adjusted tension. then rechecked again after rotating the engine a few times. will this be close enough until i get it on the rolling road.
cheers maxiboy.
If you havnt got factory timing figures, just zero them,\ and adjust according to rolling road data.
best way to determine tdc is using a tdc tool in the sparl plug hole, or by eye with a bit of rod on top of the piston.
the way you've done it, youve assumed peak lift is half way down the bore...
i used a dial gauge on the pistons though the plug hole with the plug out to determine tdc. those were the figures supplied by piper. peak lift at 110 degrees after and before tdc. wouldn,t give me lift at tdc figures like you suggested.
sorry..when u said you had dti set up, I thought u meant on the lifter!
sounds like uve got it sorted then :D
you think so :D thats a load of my mind then. hoped that was the correct way. had a nightmare yesterday. could not get the wire rings to stay put while i fitted the head the snapped the bolt in the crank pulley then my dti gauge was to short so had to make extensions out of aluminium welding rods. just happy the heads back on and the cams are timed in right. well a least they do knock when turning it over. think i,ll go and bolt some more bits on know then. cheers stan. will have to get you a drink when i come down your way.
cools...also game for a drink :D
What did piper say about your cams in the end? did you suggest they were to tame?
yes i suggested they need more lift but that duration was fine. there designer said that with the turbo they didn,t need more lift really. so as i,ve been so long without the car i thought i,d give them a go and see what she,ll do. can always change them if the prove crap. but at least it will only be a weeekend job for you then. :D so i thought suck it and see. :twisted:
coolio, cant wait to see it running!
and me. its been a while :oops:
same with mine mate....not long now tho grrrrrr lol
Reading the first post it doesnt make sense to me.
There are 2 ways to time in cams, peak angle or Lift@tdc.
First thing to do is accurately get TDC, and using those silly little plastic timing discs are a plain waste of time......the flywheel markers are more accuarate if you cant get a 15" degree wheel on.
To find TDC you need to setup a wire marker then wind the engine to approx TDC. Setup your DTI and rock the engine back till the value starts to drop, mark the degree...wind it forward and do the same...half way between is TDC. Re centre the crank to calculated TDC and re-align the timing wheel.
To setup cam timing using peak angle, set the crank to peak angle and adjust the cam to peak lift. Then rotate backwards and note the deg at which it starts to drop off, mark.........rotate forwards and do the same. True peak lift is half way between the two assuming an symetrical cam lobe. Do the same for the other cam.
To do lift at TDC, which i feel is more accurate, just set the engine to TDC and rotate the cams until they are at the designed lift values at tdc. Since you are on the flank there is zero dwell to worry about. To check lift set the engine to tdc and rotate the engine forwards to measure ex lift, when the DTI stop measuring lift your on the BCD and thats the lift at TDC value, adjust vernier till you have the correct value. The same is for intake but you rotate the cam counter clockwise and you'll have to wind the engine forwards 90 deg the backwards to tdc so you can eliminate cambelt slack.
i didnt get it first time round, but sounds like he's got it sorted using peak lift @ XX
I didnt understand the finding tdc by halving peak lift....still dont.
im assuming he meant dwell around tdc, not lift.
at first i thought he meant (180+EO+EC)/2, assuming symetrical lobe...but that clearly isnt what he's done lol.
no finding tdc by halving the degrees of rotation when the piston reaches max height and then drops again. and i used the peak angle method as i was not given lift at tdc figures. lets hope i,ve got it right. cheers both of you for looking your knowledge has been invaluable during this build.
cheers maxiboy
no worries.......i want a go though!
no worries. be nice to have some other opinions once it,s sorted.
when u reckoning on it being running?
depends. was going well but i bought another property for conversion today so will have to spend some time on that again now. but fingers crossed within a month or so. engines nearly together just finding time to get it installed.
VIPERONE
10-03-2007, 16:41
:lol:
will be an interesting drive...
what clutch have u used?
running a four plate paddle clutch with uprated cover.
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