Roller rockers
#1
Roller rockers
So I seen a video today trying to say roller rocker arms gain 20+ hp is this true I find it hard to believe but I would like to know if it's worth the money.
#2
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Year: 2001
Model: Cherokee
Engine: 4.0L non 0331 head
So the video you SAW was potentially correct assuming every other thing in the engine is in tip top shape and probably has other performance parts on it.
#3
Fresh
Well I have a fresh rebuild, with a port and polished head, heavier valve springs, bigger cam, header, and a few other new things, next i was looking at injectors and maybe roller rockers. If it's worth the time and money.
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Year: 2001
Model: Cherokee
Engine: 4.0L non 0331 head
I'd say that with your application, definitely yes.
#6
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Year: 1990
Model: Cherokee
Engine: 4.0
The rocker arms are a simple lever. The ratio between the point the lifter presses to the pivot point and the point the rocker presses on the valve increases the distance the valve is opened. Follow me? Here's a link to better explain what I mean: http://www.jegs.com/s/tech-articles/...atio+Explained Increase the ratio, increase how much the valve opens.
That said, the roller end simply reduces the friction in the drivetrain. That's definitely good, but doesn't increase power. Do not buy roller rockers in the same ratio as what you have because you will see no power increase. Before buying a higher ratio, verify you will not have clearance issues. I am not sure about jeep engines, haven't messed with them before, BUT I know LS1s you must be VERY careful with the amount of lift on a cam and higher ratio rockers because you can slam a valve into a piston. The correct way to identify clearances is to put clay on the top of the piston, rotate engine, and check for impressions in the clay. There are other ways to check for clearance, I suggest Google.
That said, the roller end simply reduces the friction in the drivetrain. That's definitely good, but doesn't increase power. Do not buy roller rockers in the same ratio as what you have because you will see no power increase. Before buying a higher ratio, verify you will not have clearance issues. I am not sure about jeep engines, haven't messed with them before, BUT I know LS1s you must be VERY careful with the amount of lift on a cam and higher ratio rockers because you can slam a valve into a piston. The correct way to identify clearances is to put clay on the top of the piston, rotate engine, and check for impressions in the clay. There are other ways to check for clearance, I suggest Google.
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Year: 96 & 88 4 dr Cherokees
Been there...done that (clay checks)
Gotcha....but the original post mentioned nothing about changing the ratio too.....my comment was on just using roller rockers to get rid of the friction and gain a slightly stiffer rocker assembly.
Changing the ratio too can add hp......until ya smack a piston top....
Gotcha....but the original post mentioned nothing about changing the ratio too.....my comment was on just using roller rockers to get rid of the friction and gain a slightly stiffer rocker assembly.
Changing the ratio too can add hp......until ya smack a piston top....
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Year: 1990
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I know the OP didn't mention a ratio change, I wanted to educate if he was unaware or anyone else reading. It is my understanding changing to roller rockers (same ratio) will net a more reliable valve train but will not net noticeable horsepower increases. To net horsepower you must increase the ratio also.
Many modifications people neglect to mention important details. I feel this may be one of those situations. If someone claims noticeable horsepower increase from roller rockers, I believe they changed the ratio also and neglected to mention it. Similar to changing to 4 hole injectors, was it the injector type change that increased power or the fact the old ones were filthy and leaking? Similar to claiming a Holley carburetor increased throttle response and power over a Rochester that was on the engine, when in reality they added a 600 CFM 4 barrel in place of the Rochester 2 barrel that's maybe 300 CFM.
Many modifications people neglect to mention important details. I feel this may be one of those situations. If someone claims noticeable horsepower increase from roller rockers, I believe they changed the ratio also and neglected to mention it. Similar to changing to 4 hole injectors, was it the injector type change that increased power or the fact the old ones were filthy and leaking? Similar to claiming a Holley carburetor increased throttle response and power over a Rochester that was on the engine, when in reality they added a 600 CFM 4 barrel in place of the Rochester 2 barrel that's maybe 300 CFM.
#9
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I know the OP didn't mention a ratio change, I wanted to educate if he was unaware or anyone else reading. It is my understanding changing to roller rockers (same ratio) will net a more reliable valve train but will not net noticeable horsepower increases. To net horsepower you must increase the ratio also.
Many modifications people neglect to mention important details. I feel this may be one of those situations. If someone claims noticeable horsepower increase from roller rockers, I believe they changed the ratio also and neglected to mention it. Similar to changing to 4 hole injectors, was it the injector type change that increased power or the fact the old ones were filthy and leaking? Similar to claiming a Holley carburetor increased throttle response and power over a Rochester that was on the engine, when in reality they added a 600 CFM 4 barrel in place of the Rochester 2 barrel that's maybe 300 CFM.
Many modifications people neglect to mention important details. I feel this may be one of those situations. If someone claims noticeable horsepower increase from roller rockers, I believe they changed the ratio also and neglected to mention it. Similar to changing to 4 hole injectors, was it the injector type change that increased power or the fact the old ones were filthy and leaking? Similar to claiming a Holley carburetor increased throttle response and power over a Rochester that was on the engine, when in reality they added a 600 CFM 4 barrel in place of the Rochester 2 barrel that's maybe 300 CFM.
Which is why I said 20 HP may be a bit much.....same ratio...nill in the HP department, but you do get a more reliable valvetrain with less deflection
change ratio, maybe 15-20 hp, depending on other stuff.