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Rocker Arms-increased ratio worth it?

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Old 11-20-2005, 05:35 AM
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Default Rocker Arms-increased ratio worth it?

Looks like all of the 1.8:rockers cost a ton, but a substantiall savings in labor over doing a cam (in a Vette anyway).

Any dyno comparison of a LS1/LS6/LS2 with stock rockers, vs high lift rockers? Just wondering if you can gain anything with extra lift but stock duration.

I may do heads as well, but really don't want to tear into the timing cover (gotta remove the steering rack in the C5/C6)

Thanks
Old 11-20-2005, 06:05 PM
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Go for the heads too sliding the rack out takes no time at all - just got done doing it a couple hours ago.

What are you driving these days Dave? Are you still racing? Did you decide to keep the car? I'm the one that was working with Donovan on his WC kit. His car is for sale if you know anyone looking.
Old 11-21-2005, 07:55 AM
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Thunder racing cams say dont use them because of ramp speed.

I wonder how many TR cams are using them
Old 11-21-2005, 04:32 PM
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my idea was to use the rockers with ported heads, but NOT changing the cam. You basically get a 5% increase in lift (which my heads can handle), but no increase in duration.

Any thoughts??
Old 11-21-2005, 05:20 PM
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for the money on the rockers,you will not make a gain that is worth it. even a z06 cam will net you 15hp and it's still a stock cam. for the money vs hp....get a cam.
Old 11-21-2005, 06:18 PM
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Originally Posted by mike c.
for the money on the rockers,you will not make a gain that is worth it. even a z06 cam will net you 15hp and it's still a stock cam. for the money vs hp....get a cam.
Old 11-28-2005, 12:20 AM
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The 1.8 roller rockers will increase lift appox. .031 and increse duration. I got my Yella Terra 1.8 shaft mounted roller rockers from TR for $500. The fit right the first time with no mods needed to the rocker covers. When I did mine I added Chromoly push rods and Comp 918 springs. What a difference this combo makes.
Old 11-28-2005, 12:39 AM
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A very easy an accurate way of knowing how much extra lift you get is by taking your actual lobe lift and multipling it by your rocker arm ratio....... .300 * 1.5 = .450 for example. Rockerarm ratio is determined by the distances between the pushrod cup, the rocker pivot and the tip that pushes agaist the valve stem.

Ron
Old 11-29-2005, 04:30 PM
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I vote for doing the cam kit also! easily expect 30+ at the tires with a cam kit and a tune..you can get just about any shop to do the cam swap for a reasonable price and why take the heads off and leave a stock cam in??
Old 11-30-2005, 01:55 PM
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I have seen 15-18hp from 1.8 rocker and Harland Sharps are cheap. Yes a cam swap will increase more but for the money and drivability? 1.8 rockers are for those that do not want to go into a cam swap.

Nate



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