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Discussion Starter #1
Hey guys,

I'm about to install my new BC 272 cams. I need some guidance with aftermarket cams. I'm reading 2 or even 3 different ways to install them in the forums. Which is safest incase they do make the motor interference?.

Do I place crank 15deg BTDC, install the cams as per TSRM, lock pins at 11'oclock and 3 o'clock, torque down evenly? When does t-belt go on? How do I tdc all 3 notches without damaging valves??

Thanks in Advance!
Jay
 

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Mind if I do a J?
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I held your hand via PM through the entire process. What is the hold up now? I've installed 6 or 7 sets of high lift cams in 2J motors since the last PM you sent me.
 

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Discussion Starter #4
Sorry man, I'm so worried that these make my motor Interference. I'm just uncertain of the orientation of cams/crank with belt off when installing cams, then how to get it back to TDC without bending a valve...
 

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Mind if I do a J?
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Hey man you can lead a horse to water but you can’t make him drink. Good luck
 

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Game Over
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I usually torque the cam caps down with the cams positioned to where the cams would go down as evenly as possible to reduce the possibility of snapping a camshaft due to the length of these cams, and due to the higher lifts of aftermarket camshafts. Make sure all the journals are clean, and have oil or assembly lube.
I still try to keep the alignment pins of the cam relatively close to the timing mark, but it's usually within 120 degrees give or take, if memory serves.

I leave the crank a couple degrees BTDC so when the cams are torqued down so the valves wouldn't touch the pistons as the cam is being bolted down, as keeping the crank BTDC keeps the pistons down below the deck of the block.

Also, when you Carefully move the cam and crank seperately by hand with the belt off, you can feel a difference in feel between valve spring resistance, and a valve touching the piston. There is literally zero give when a valve touches a piston in a interference engine, as opposed to a valve spring that progressively builds resistance as you turn the cam.

That's when you make sure you DON'T force it, and move the crank further AWAY from TDC by hand if necessary, to move the pistons out of the way until you can freely turn the cams 360 degrees to follow the TSRM procedure of loosening, and re-torquing the cams cap every 120 degree angle of the cams, until your timing mark of your cam gear matches the rear timing plate.

Then you move the crank back to TDC before you start moving either around to install your T-belt, and setting your T-belt slack.
For the timing belt, you want to set the slack on the TENSIONER side, before you pull the grenade pin.
 
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