The "WRONG" Way To Adjust BBC Valves!

[savatreatabvr]

I've posted questions on this forum many times and I've gotten some excellent answers to fix what problems I had at the time but my mid 70's BBC 454 still didn't run right until today! Well runs better anyways! I was doing the running adjustment procedure wrong, I was backing off the rocker arms until they clattered and then tightened them until they stopped clattering and then another 1/4 turn and that was it and that why it always ran rough! Today I read an article on the right way to do a running adjustment, I was doing everything right EXCEPT waiting 10 seconds after the first 1/4 turn and turning them another 1/4 turn waiting 10 more and 1/4 turn and 10 more seconds and one final 1/4 turn, after each turn it would run rough until the lifters adjusted themselves and now it runs much better but there's still one thing, I STILL DON'T HAVE BBC POWER! So now I'm wondering if I have timing issues! It's still a great truck no matter what!

I don't care how high gas prices go I'll never own a rice burner!

[vegas80step]

I've learned to celebrate the little victories!
also good info to know... thanks for posting..

[INSIDIOUS '86]

Your prob used to open chambered rect port big blocks with high flow intakes and way better cammed. Not a sloppy just torque bbc in a truck
Posted via Mobile Device

[BigBlocksRule]

If it's a 70's 454, should be an oval port, low compression build. If you have too much cam, it'll be a slug. I'd check timing...

Learn to adjust 'em with the engine off and you'll make a lot less of a mess. You've tightened yours down to zero plus 3/4 turn, which is where a lot of guys set 'em. Should be fine.

[savatreatabvr]

That's a good question, I've got no idea what the 454 has internally because it was in the truck when I bought it, originally it was a 350. The timing tab IS MISSING, I've got it timed by ear good enough for it to run but any ideas on how to fine time it without the tab or can I put another timing tab on it and exactly where?

Originally Posted by BigBlocksRule

If it's a 70's 454, should be an oval port, low compression build. If you have too much cam, it'll be a slug. I'd check timing...

Learn to adjust 'em with the engine off and you'll make a lot less of a mess. You've tightened yours down to zero plus 3/4 turn, which is where a lot of guys set 'em. Should be fine.

[beamn7]

Well, you could do the old "street timing" method. Have a buddy pop it in drive and power brake it up to about 1500 rpm or so and hold it there. While he's doing that, advance the timing slowly until she starts to ping and back it off a bit.
I would still recommend getting a timing tab for it but this will get you close if not a little advanced....
Be sure to drive and listen for any pinging on heavy load / full throttle....

[savatreatabvr]

That's the best way I've heard so far, thanks Beamn7!

Originally Posted by beamn7

Well, you could do the old "street timing" method. Have a buddy pop it in drive and power brake it up to about 1500 rpm or so and hold it there. While he's doing that, advance the timing slowly until she starts to ping and back it off a bit.
I would still recommend getting a timing tab for it but this will get you close if not a little advanced....
Be sure to drive and listen for any pinging on heavy load / full throttle....