Hot Rockers
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Registered User
Joined: Apr 2002
Posts: 694
From: Milledgeville, Ga USA
Hot Rockers
Man these things are awesome...I don't know if you no what these are, if you don't take a look here cause it takes way too long to explain! : www.hotrocker.com
What do you guys think about these??? only $900
If I had the money I'd get them!
What do you guys think about these??? only $900
If I had the money I'd get them!
Registered User
Joined: Oct 2002
Posts: 2,931
From: Upstate NY
Not to be a wet blanket, but...
Where did they get a 228* cam with .394 lift (1.5 rockers). Even OEM's don't get that mild on the flanks.
83 (almost 35%) more hp @ 5250 with just rocker arm ratio?
120 (almost 52%) more torque at 4000 with just rocker ratio?
85% of max torque from 1750 to past redline.
90% of max torque from about 2600 to 5100.
WOW! OEM's need variable valve timing of up to 50 crank degrees to achieve those numbers.
325 max hp? 361 max torque? GM's aftermarket Vortec head HO crate engine makes 330 hp @ 5000 and 380 lb-ft @ 3800 with less cam. (212/222) and costs about $2250 for the complete longblock with all new parts. Tell me why I want to spend $900 just for rocker arms?
Yeah, I guess I am a wet blanket.
Where did they get a 228* cam with .394 lift (1.5 rockers). Even OEM's don't get that mild on the flanks.
83 (almost 35%) more hp @ 5250 with just rocker arm ratio?
120 (almost 52%) more torque at 4000 with just rocker ratio?
85% of max torque from 1750 to past redline.
90% of max torque from about 2600 to 5100.
WOW! OEM's need variable valve timing of up to 50 crank degrees to achieve those numbers.
325 max hp? 361 max torque? GM's aftermarket Vortec head HO crate engine makes 330 hp @ 5000 and 380 lb-ft @ 3800 with less cam. (212/222) and costs about $2250 for the complete longblock with all new parts. Tell me why I want to spend $900 just for rocker arms?
Yeah, I guess I am a wet blanket.
Registered User
Joined: May 2000
Posts: 1,327
From: Under my Car as usual :)
Those things are ooolllddd... You could probably o a search and find a hundred threads on it. I dont' think the technology is all that great. I mean really, Vtec isn't all that special 
-Shannon
-Shannon
Registered User
Joined: Jul 1999
Posts: 128
From: Tx
V-Tec is a cam-changing design and it's very compromised toward it's long duration camshaft change. Without a much more complex actuation, and a 'system' built in accordance to power output at varying levels, there are always going to be compromises in these types of designs.
The problem with this system in particular (as I see it) is one of durability. The rocker arm is weak in it's most critical area, directly below the arm, and the little 'actuating-notches' don't help the situation much either. With this system you get one thing... variable lift which has a few advantages to it but not as much as they'd like you to believe. What you don't get is a system that works in concert... ie, variable lift, variable timing and variable runner length. From there, we work towards a throttle-less system like the BMW Valvetronic. Big advantages there but it's also very expensive to design and manufacture. Even at it's best, you might see a 15% increase in engine performance with much lower emissions and markedly better fuel economy.
I'm not going to say the system doesn't work, I just believe that you would not want something like this in a high performance application. The rocker arm looks like a real weak link and I think the harmonics of the system would really limit top end power. Those are my thoughts... no actual data, just a few years actually building custom shaft-mount rocker systems for many of our customers. Take from it what you will.
Take care,
Chuck Riddeck
Progressive Race Engine Development
The problem with this system in particular (as I see it) is one of durability. The rocker arm is weak in it's most critical area, directly below the arm, and the little 'actuating-notches' don't help the situation much either. With this system you get one thing... variable lift which has a few advantages to it but not as much as they'd like you to believe. What you don't get is a system that works in concert... ie, variable lift, variable timing and variable runner length. From there, we work towards a throttle-less system like the BMW Valvetronic. Big advantages there but it's also very expensive to design and manufacture. Even at it's best, you might see a 15% increase in engine performance with much lower emissions and markedly better fuel economy.
I'm not going to say the system doesn't work, I just believe that you would not want something like this in a high performance application. The rocker arm looks like a real weak link and I think the harmonics of the system would really limit top end power. Those are my thoughts... no actual data, just a few years actually building custom shaft-mount rocker systems for many of our customers. Take from it what you will.
Take care,
Chuck Riddeck
Progressive Race Engine Development
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