So based on your advice a few weeks ago, I went ahead and got the Powerbond 25% UD Pulley.
When I got it I took it out of the box and noticed that the pulley itself was keyed. Sweet, that should make it easy I thought.
So today, I went to play with the motor, got the stock pulley off no problems but then noticed that the stock pulley does not come keyed. Weird?
Why did my Powerbond come keyed if the snout itself is not keyed? Further to that, why did my pulley come with timing marks if there is no way to ensure I have installed the new pulley in EXACTLY the right position to be timed. Even if the snout got pinned, how can you gaurentee if is timed to the exact degree.
I realise that these pulleys are interference fits but hopefully you guys can answer some of these questions.
How to I ensure the timing marks on the pulley are actually the timing values. I’d like to use the timing marks on the pulley to sync timing with my ECU.
Cheers boys and thanks in advance.
ps - I got a new GM bolt, what do I TQ it to when I slap it all back together.
You dont have to sync it to the PCM, notice ther no reluctor wheel, or pickup for anything on it. The crankshaft as a reluctor on the back gen3 in 24x gen4 is 58x, and the cam has a 180* offset phased pickup on the back (gen3) Or gen4 is off the upper timming gear.
thats normal your stock crank dosn’t have a key or anything. The keyway works for aftermarket cranks that have one also, or if you can have a stock crank done at a machine shop.
you can put the ballancer on anywere you want right now, and be fine. You can use a piston stop in the plug hole, and find about were TDC is. Or just look in the plug hole. Make a arm or just a note/mark on the front cover around were your TDC is and use the marks on the powerbond. Remeber the powerbond might turn a little as you install it unless you have a install tool. With a tourington bearing, that will not make and fiction on it during install. The markings are more for if you change to dizzy, but the can be usefull if you have a soild cam, or just nice to have working on the valvetrain. I’ve just put a sharpie line on the front cover to the side at 10ock’ish on cars I work on often.
the tq spec is somthing dumb like 70#s and 140*
Ive never done that, just some locktight and max impact gun. Never had problem.
you have the smaller belts you need?
Cool, I’ve never actually seen the wheels on an LS1 in position, does the first trigger event happen at exactly TDC? I’m actually not using the factory PCM. I’ll be using a stand-alone for this build and need to confirm mechanical and electrical timing. If a timing reference event is at TDC, that’s easy because I can just sync to 0 degrees offset.
Cool to know. I’m still a little amazed there is no more precise method.
Yeah, I think I’ve seen that spec, some guys are also saying like 200+ tq on the wrench.
The keyway is for people with aftermarket crankshafts. You will not have to worry about the timing marks. I use a tool I built at the shop to install these balancers. You can do it with a bolt but the crankshaft threads are very weak the press fit is tight because they don’t use a keyway stock. I do not recommend the old bolt or longer bolt method to install the dampner.
Crankshaft bolt torque (new bolt) 37ft.lbs then another 140°. Be prepared to have a very long 1/2" ratchet or breaker bar and a wall to lock the flywheel to prevent the engine from turning
