Explain this.

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tekslk

tekslk

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Going from a hyd lifter and rocker assyemly, to a hyd lifter with 1.6 roller rocker, what exacly does this do for car as far as performance, rpms etc.
 
beside making your wallet lighter...the 1.6 roller rockers are give ya more lift at the valve..

stock rockers ratio is listed as 1.5 ...but they are really around 1.45 and usually two are not the same..

so you get a more precision rocker arm...besides looking prettier...the rockers ...not you...LOL
 
Is it worth changing over? Will I be able to feel the diffrence? Here it?
 
If the cam you have is a .500 lift at the valve, the. To find out the new lift, divide the lift (.500) by the rocker ratio of 1.5 and the multiple it by the new ratio of 1.6. The math looks like this.

.500 / 1.5 x 1.6 = new lift.
.500 / 1.5 = .3333333 x 1.6 = .533333333

You valve springs should be changed out for the new valve lift if they are not capable of the new lift.

In addition, the quicker lift intensify's the cam's duration by approx. 2*'s @ .050.

Is it worth the change? In the way you described?

Well, a lot depends on what your doing and what your engine combo is. On the whole I'd say no. But it is a worthy upgrade when you are looking to race. That would be for the aluminum rocker in either ratio. Having the valve open accurately to the full potential lift is a lot better than the sloppy OE rocker stamping.

No, you won't feel it and would be hard pressed to see it on the E.T. slip.
 
If you need to ask, then I'd say, no, it's not worth it.
 
tekslk said:
Going from a hyd lifter and rocker assyemly, to a hyd lifter with 1.6 roller rocker, what exacly does this do for car as far as performance, rpms etc.
Click to expand...


It won't affect the power band, as the duration will not change. Just the overall lift and speed of the valve opening will change. It will flow better at max lift of the cam.

It will also get lower MPG with more lift.... :banghead:
 
70aarcuda said:
beside making your wallet lighter...the 1.6 roller rockers are give ya more lift at the valve..

stock rockers ratio is listed as 1.5 ...but they are really around 1.45 and usually two are not the same..

so you get a more precision rocker arm...besides looking prettier...the rockers ...not you...LOL
Click to expand...

Prettier rocker arms....now he would need clear valve covers to show them off....
 
Keep in mind too that aluminum rockers will fatigue and fail a lot faster than steel rockers. I would stick with steel unless you are racing and need every extra HP.
 
tekslk said:
Going from a hyd lifter and rocker assyemly, to a hyd lifter with 1.6 roller rocker, what exacly does this do for car as far as performance, rpms etc.
Click to expand...

Open the valves further for example a .528 cam will be about .557 lift with 1:6's. Unless your heads flow in this area it won't do much if anything for power. It will be harder on your train.

I had gold race crane's and had nothing but trouble with them. They were 1:6's.

I currently have 1:5 ratio harland sharps. They are about 15 years old, never failed and hold lash like a bear trap. I adjust them once a year and I drive alot.

I would not buy the 1:6's again but they allow you to take advantage of ported heads or you can stagger a cam by only using them on the exhaust. Personally i'd rather make my lift with the cam, not the rocker.
 
Very insteresting, Im running eddy heads air gap intake holley 770 it runs good and its winter and Im basically searching to see if I want to spend money in this direction.
This is a fast street car but it sounds like maybe I should leave well enough alone.
 
The hughes are a nice set.
same price for 1.5 or 1.6
Often the added lift gives you more midrange power.
 
Price wise, roller rockers aren't for everyone, but I still think it's a worthy upgrade over stock stamped. The Eddy's would probably appreciate the extra lift of the 1.6 being how your cam is in the .490" lift range. I think the real issue with durability is, just making sure the setup is correct.....meaning proper length push rods for a clean valve sweep and checking pushrod clearance thru the head.
 
I'm not sure how much you would feel. Like they said - it adds lift, and it quickens the rate of lift and closure (because it moves further in the same number of crankshaft degrees). It will give you a more consistent racker ratio, and you will get more stability because they won't flex. So you might see more rpm depending how bad thigns are now. You also are asking more of your valve springs (because the ratio change works against them) and you make have geometry problems depending on what heads you have and whose rockers you settle on. It's a big chunk of coin IMO if you don't already need them.
 
I t has double valve springs on now with eddy heads, Im wondering also about clearance.
 
If you have eddy heads and double VS I would say you should be runing a roller rocker but i'd go 1.5's.

Clearence should be an issue with most aftermarcket valve covers but it's easy enough to measure.
 
are you doing a rocker upgrade and are deciding between 1.5 or 1.6 or you just searching for more power ? if your looking for more power id spend my money somewhere else like more cam. what cam are you running ? if its high lift with fast ramps 1.6 might make it hard to control valve float. whats your combo?
 
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