Like the old saying goes: wanna play? U gotta pay. Kim
1.5 vs 1.6 rockers
- Thread starter 318willrun
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512Stroker
We are all here because we are not all there.
If you make to move from 1.5 to 1.6 ratio.
Do you need to worry about the valve to piston clearance?
Do you need to worry about the valve to piston clearance?
Donnie514
Well-Known Member
I know this is not the question, but post # 10 talks about price.
When going to H/S 1.6 rockers I also had to go to longer valves, keepers. retainers, custom Smith Brothers push rods, etc.
Now mind you I have a cam with some pretty healthy lift.
When going to H/S 1.6 rockers I also had to go to longer valves, keepers. retainers, custom Smith Brothers push rods, etc.
Now mind you I have a cam with some pretty healthy lift.
512Stroker
We are all here because we are not all there.
If you make to move from 1.5 to 1.6 ratio.
Do you need to worry about the valve to piston clearance?
Do you need to worry about the valve to piston clearance?
U should at least check it. Cause u know what happens when the piston kisses’s the valve. Kim
in my situation, no.
The 1.6 change will tame a "lopey" cam duration at idle for sure.
More importantly, increased RPM ramp speed and a bit more topend power. On My "B" block street set up.
IMO.
More importantly, increased RPM ramp speed and a bit more topend power. On My "B" block street set up.
IMO.
Worry? Yes. Why? You never know how much clearance you have let from the change even if you write down what clearances you had when you put it together the first time. CHECK! A small price to pay to avoid a high dollar screw up.
I don’t know how that is possible when it will intensify the cam. Not mello it out.
And there’s the proof.....
Total duration does not change.
Duration at .050 changes because you are measuring lift to attain @.050 vs sensing movement @ .000 and Because the 1.6 moves the valve further with each degree of cam rotation.
1.6s are essentially changing your lobe ramp speed...
Duration at .050 changes because you are measuring lift to attain @.050 vs sensing movement @ .000 and Because the 1.6 moves the valve further with each degree of cam rotation.
1.6s are essentially changing your lobe ramp speed...
This is mainly why I bought some 1.6 rockers. That and I found a couple sets at a price I couldn’t turn down. I ran several of Jim’s cams (racer brown) and they seemed to really like a 1.6 on the intake side but then again most of those cams were under .550 lift. My 422 Indy engine assembly came with 1.6 ratio rockers that are in use now but I plan on upgrading over the winter to some 1.6 T&D rockers I bought from a guy when his engine exploded on the dyno.
yellow rose
Overnight Sensation
trapster
Well-Known Member
Adding 1.6 you are also putting more drag on your timing chain and all components in between.
1.6 Will change the duration because you will be taking up the valve lash faster. but not much. the more lash the more change.
1.6, You should check your piston clearance and also the max spring compression.
Adding 1.6 will give you more power if you have smaller valves. or shorter duration or smaller lift than optimal.
1.6 Will change the duration because you will be taking up the valve lash faster. but not much. the more lash the more change.
1.6, You should check your piston clearance and also the max spring compression.
Adding 1.6 will give you more power if you have smaller valves. or shorter duration or smaller lift than optimal.
thanks... appreciate it
Yeah, but you're still stuck with the rocker arm homework assignment. Better get to it, procrastination never gets anything done.
U will more than likely have to open up ur pushrod holes. Kim
trapster
Well-Known Member
shouldn't have to , but it is always good to check.
are you saying the cast rockers are a different ratio closer to 1.5?
How so?
As well as bigger valves, long duration cams & high lifts.
The thing is, if the engine can use it, it will show up on the dyno. So, saying what you said is only half true and limiting that facts.
Part of this is getting the max out of your engine is rarely what people do or want since it would lead to a crappy street engine and driver.
No, less than 1.5.
Almost without fail they are. But not necessarily "closer" to 1.5 as rumblefish pointed out, but they are almost always more consistent. If that makes sense.
Yup, that’s it. Kim
Sometimes adding more ratio helps, sometimes it doesn't. It usually doesn't hurt. More ratio only adds power if the engine needs the valves to open quicker and further. Some engines don't need the intake valve to open faster, some do. There is no absolute answer, it just depends on what the engine needs.
My cam is small, the specs are .427/.454 lift and 204*/216* @ 050 and 112 centerline. The rest of the 360 is stock, except I put a 4bbl on it.
j par
Well-hung Member
Except the air cleaner except the four barrel except the four barrel intake except the cam except the lifters except the headers LOL... Bone stock! LOL....
huh...??? I was answering AndyF about 1.6's being a help to my combo.
But to answer your remark about my engine, my crank, rods, pistons, heads, valves, ports, pushrods, and rockers are all stock or OEM replacements. And a factory cast intake/TQ would work as well as my intake/carb for performance. Oh, you didn't mention the gaskets, paint or plug wires, they aren't factory bone stock either! Air cleaner? LOL... Pure Doofus.
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You’ll pick up power....
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