I dont know if i have set the lifters right on my car.

The block and heads are stock.....89 RS Camaro TBI. I have rebuilt the engine.

When i set the lifters I rolled the engine to the proper place, then tightened half and rolled the engine again to tighten the second half.
The intake was off when I did this so i was careful not to compress any lifters.

After intake was mounted and a lucky guess on timing the car fired first try.

With the engine running I carefully tightened each lifter until it just stopped chattering and then gave them a 1/4 turn...and so on with each lifter.

Was that ok to do on the 305?

 

First, ditch the colors. Seriously dude. Yes, you did fine. Some people like to go a half turn, it doesnt matter though, no chatter you should be fine.

 

How do you know if its too much.... 1/4 to 1/2 sounds like guess work.

 

Its a preference and application thing. On a nearly stock to mild engine, most people go 1/2 turn past zero (point of no clicking). Personally, on a mild (little more than stock) I like to go 1/4 turn. They are hydrolic lifters though, so if you go 1/4 on some 1/2 on others and even 3/4 on some other ones, you will not notice a different. At least not on the level of engine we are speaking of.

 

Does a high volume oil pump change anything?

 

No, a high volume pump doesn't change anything.

One full turn down from zero is the proper adjustment. I've done the 1/4 or 1/2 turn thing for years, heard it would help the engine rev higher but valve train was always noisy. Finally did 1 full turn down on the Camaro last year - viola, runs great and no lifter noise.

 

Most service manuals recommend 3/4 turn. The cam installed wont matter since the adjustment is done with the lifter on the base circle of the cam and it needs the correct preload.

My 97 LT1 runs much weaker with the lash set loose,like just enough to make it quiet. 3/4 preload and it runs much better. I tested that theory with timeslips.

 

I would be curious to see someone run 3runs at 1/4 turn and 3 runs at 3/4 turn and show a consistent difference. I dont see it happening.

They need to be tightened down till they arent noisy, as five7 said. I have always been able to get away with 1/4 to 1/2 turn and not have noisy valvetrain on my SBCs.

 

You can tighten them to zero lash and 1/8th turn past and they will be quiet. Thats where I had my 97 adjusted to and it would only run a 14.10 at best. This was after several runs to. Once set to 3/4 turn it ran a 13.62. I never would have thought it either. I suppose it's something like solid lifter cam in that a few thousanths can alter the power some. Maybe the air was cooler on the quicker run but the car felt stronger to so I know it makes a differance. Now,on a lower hp 305 it may not be as drastic of a change but I always go 3/4 turn past 0 lash on a SBC hydraulic cam. The only exception would be if a cam company advised otherwise.

 

To be honest, and I am not trying to sound like a jerk, you didnt gain .5 second by tightening your rockers up a 1/2 turn. On a solid lifter cam a few thousands cam take the cam out. The difference is that on a solid cam if you were running a few thousands looser you would be losing some lift because of it. On a hydrolic cam when you hear no noise you have hit the point of zero lash, and any past that you are going to realise the full lift of the cam.

 

You dont come across like a jerk at all. I dont think that was all of it either. I'm thinking it was a cooler day for the quicker runs and I may have gotten a better launch,who knows. But what I am saying is that it did help some and I could physically tell the car ran better. So I always set mine to 3/4 after 0 lash.

 

When I worked at Chevrolet most all service manuals said 1 full turn.

Really it's not going to make to much difference although I wouldn't go less then 1/2 myself.

If you measure it out you will find that 1 full turn is .050 and that will center it in the lifter (hydraulic is what im talking about)

 

Now thats neat to know. I have used the Chilton's and Haynes manuals and they say 3/4. I'd rather go by a GM manual though.

 

If you go too tight wouldn't that increase parasitic drag (albeit slightly) and also wouldn't it not allow the valve to fully close? Or are we talking like 2-3 turns for that to happen? I've always set mine at 3/8-1/2 for that very reason but this thread has me thinking that if the weak hydraulic lifter gives at all being set that loose I won't realize full cam lift (all .350" of it ).

 

I had a '79 elcamino, the guy who had it before me had half of the lifters really tight, prob 3-4 turns past 0! and the other half really loose(clacking away!) with no preference towards intake or exhaust. they were all very different. it was ran noticeably better when I readjusted the valves!

 

No, it wouldn't increase drag. The plunger is loaded against an internal spring, but the difference in force between 1/4 and 1 full turn is insignificant.

The theory from days of yore was the lifters would "pump up" during high RPM operation and cause the valves to not fully close. If you only turned them down 1/4 to 1/2 turn and the lifters "pumped up", the valves wouldn't be held open as much. That may have been the case 50 years ago with hydraulic lifters, but it certainly isn't the case anymore.