am i reading this correct? ( dialing in cams )

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rx jamie

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according to that chart ''timing events correct @ 0.050 inch lift '' therefore........the inlet should be open 0.050" (1.27mm) at 7 degrees before top dead center? and the inlet should have 0.050" to left close at 31 degrees after bottom dead center and so on? or am i reading this wrong?
 
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Phil74

Phil74

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Yea that right, solid lifters just let you not have valve bounce and rev to a higher rpm. You have squeezed all the oil out of the lash adjusters when timing these cams?

Your using a dial gauge for this? Silly question i know.
 
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evo arm's m7960

evo arm's m7960

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so looking at this pic of the timing tag , will the max lift for the cam's be around 109 in and 110 ex

eg inlet 7 +31 + 180 div by 2 = 109 ?? or am i wrong ?

just wondering :O)

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Phil74

Phil74

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The valve begins to open 20 degrees before Top Dead Center (BTC) and doesn't close until 50 degrees after Bottom Dead Center (ABC). The lobe 'centerline' (the point of max lobe lift) is located at 105 degrees after TDC. To find the centerline, assume the max lobe lift occurs at the half-duration point (which is not necessarily so, but close enough for the purposes of this presentation). Since the valve opens 20° BTC, then the max lift (half-duration point, 125 ° of crankshaft travel) occurs at 125-20 = 105° after TDC.

With the use of vernier pulley just can advance or retard this to suit your engine the same as a mapper will advance your ignition timing for more BHP/Torque on lower RPM. The timing of the cams will depend also on head work or porting that has been done and also if your valves do not start to bounce on high RPM usually caused by not strong enough valve springs or the hydraulic lifters not being able to cope at high RPM which results in the use of solid lifters to overcome this. The higher the profile of the cam the more lift is required by the valves for the lift duration. Some people will shim the lash adjusters for this purpose but infact this will only cause harm to the cam lobes and can result in cam lobes breaking off the same as incorrect use of valve springs which will break springs, bend valves and sometimes break cam lobes due to the rockers also breaking from valve bounce, incorrect valve springs and also shimming lash adjusters to much.
 
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rx jamie

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ah excellent cheers for the feedback lads.

no i dont have solid lifters i have brand new hydraulic 3mm lash adjusters from indigo gt. but i have beehive springs fitted and titanium retainers. im running a 2.37 4g64 with a gtx35r so i wont be revving that high.

yeah i have a dial gauge and all the gear. just this timings making my head spin lol. im a time served mechanic but ive never worked on anything with performance cams before. so this is all new to me.
 
Phil74

Phil74

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Beehive springs are good for only 8000 RPM so you will drop off and peak out on your cams before the duration. I have used beehive springs with uprated cams before but these struggle from a 270 cam and are no good from a 272 cam upwards. Even if your revs are low the valve lift and duration will not give you what the 280 cams are designed for. 3mm lash adjusters do not provide any more oil than standard lash adjusters surprisingly. if you can get a set of solid lifters and i know they are expensive it is ideal for these cams and not to have valve bounce at higher RPM. You could always retard the timing a little on your vernier pulleys for low end Torque, however it will idle very lumpy so you will need to adjust the mixture and idle which your mapper will be able to do for you. As you are running a stroker crank you will have alot of BHP and low end torque presently. Head ported on the exhaust inlet and gas flowed will aid you and stop you having a vortex develop inside the head which will keep your valves open as it will not be able expel the gases quick enough. A set of uprated springs would be idle and standard valves are fine but have a 3 angle valve seat cut in the head if not already done so. Hope this helps mate :)
 
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rx jamie

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wow thats a lot of info, cheers mate :)

they are uprated springs like mate, i recommended them by a good few tuners for my spec. they are good for 11000 rpm 44psi boost and super strong and max lift they are rated to is 14mm, i mean im a strong lad.... i can bench 160 kilos and arm carl 30 kilo dumbells in each hand yet i struggled to compress those springs with the valve spring compressors LOL.

so i need to compress the oil out of my lifters if i dobnt have solid ones to dial the cams in? ive heard some people welding an old lifter? but i wouldnt know where to start with that lol
 
evo arm's m7960

evo arm's m7960

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wow thats a lot of info, cheers mate :)

they are uprated springs like mate, i recommended them by a good few tuners for my spec. they are good for 11000 rpm 44psi boost and super strong and max lift they are rated to is 14mm, i mean im a strong lad.... i can bench 160 kilos and arm carl 30 kilo dumbells in each hand yet i struggled to compress those springs with the valve spring compressors LOL.

so i need to compress the oil out of my lifters if i dobnt have solid ones to dial the cams in? ive heard some people welding an old lifter? but i wouldnt know where to start with that lol

i also read that cams should be dialed with fixed / solid lash adjusters ??


this is a good read :O)

http://www.kelford.co.nz/sole-purpose-of-degreeing-your-cam


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R

rx jamie

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excellent, just what i needed mate. needed to know exactly how tall i needed to make the lifters and that tells me. ideal
 
evo arm's m7960

evo arm's m7960

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i run bc 272's in my e4 but not got round to dialing them in yet , install straight up as per the instructions , good idle good power :O)


will be doing mine very soon

good luck mate




picture of adjustable solid lifters , should be easy to make i think ?




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R

rx jamie

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yeah shouldnt be too hard. i'll just gut an old lifters inards out, put some threaded bar down it and a nut on to adjust and pop a domed nut on top. job done :)
 
evo arm's m7960

evo arm's m7960

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yeah shouldnt be too hard. i'll just gut an old lifters inards out, put some threaded bar down it and a nut on to adjust and pop a domed nut on top. job done :)



i started making up a adjustable lifted like above " a 13mm nut and a cut down bolt " nut needs welding to the lifter really "

but at the same time i tryed just shimming the lifter top a bottom " removed the center and spring " with some washers about 11mm wide "

the nut and bolt type is easier to adjust the washer type needs some fine tuning with the last washer and a file / sand paper to get the required hight :O)

the best part about using washers is there is no damage to the lifter and it can be reused .

i tryed both out on a spare head today and both work really well :O)



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evo arm's m7960

evo arm's m7960

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hi jamie how did you get on with this ???

the reason i ask is that i have had a problem dialing in my bc 272 cams "

the card that came with them seams to have the wrong info on it compaired to the info listed on the bc web site "

the new listed data seems to match the reading on my car so im thinking it is right :O) using a soild lifter tight on the cam follower " no gap "


making a 5 deg differance to the inlet timing and a 3 deg differance to the ex timing and overlap points which made for a couple of hours of head scratching :O(

i have emailed bc and am waiting on a reply .

info@briancrower.com



please look at this link it may help but check with bc your self for confirmation befor adjusting any thing :O)


http://briancrower.com/makes/mitsubishi/cam_card/bc_0112.pdf



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R

rx jamie

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ah right..yeah id go with whats on their site.

yeah i got it all done thanks mate. done the break in period on the motor and im just waiting on a full boost map at the end of the month now. i tried a few suggestions from a few people and the timing just wasnt working until i sat down and really really thought about it. it was a certain amount of timing on the crank the valve will be open a certain amount on the dti gauge. as soon as i done that everything just came together i turned the engine over many many times by hand and rechecked a million times lol. i had loads of bits of wire pointing to the crank at different points that represented different valve lifts at different points. all came good in the end.
 
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rx jamie

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Honestly can't tell you how much I can't wait. First taste of 600 plus bhp can't come soon enough!
 
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