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Question Roller Rockers?

While looking at some of the Performance Type IV pages, like http://www.pauter.com/ I noticed they have a set of roller rockers for their Type IV engines. I know this is a must for anyone w/ an American V8 to get more power. I was not even aware of these for Type IV. Has anyone had experience with them? Would we need to do as valve adj so often using these? Just some novice engine questions in lue of the recent threads on high performance Type IV's.
By the way I have only seen these rollers on Drag and Sand Rail cars' pages thus far...ex:Sand Rail Page

Thanks for any info!
Nathan

Now if I could only afford the Nickies

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Old 02-05-2002, 05:33 AM
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As part of a full set of modifications, the roller rockers are good. By their selves, I doubt they make any difference. They are easier on big (48mm) intake valves due to the rollers and have more clearance for larger diameter/dual valve springs. They do require drilled adjuster screws and this means a lot more oil flow to the valve cover area. The increased oil flow would probably require a larger oil pump or external oil pump and a vent system to make sure the oil will get back to the sump quickly. We have had lots of troubles with pressure in the vlave covers and finally started using the CB-Performance bolt on with large vents on each cover. As for valve adjustment life I can't say as I adjust them after every race weekend. Good luck.
Old 02-05-2002, 10:02 AM
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Roller rockers?

Serve a couple of purposes:

1. Less side load on valves, as tip "rolls" across valve stem head rather than slides - lessens wear on guides and lessens mushrooming of valve stem head.

2. If rocker also has needle bearings, prevents galling of rocker shaft under high spring loads.

Other than that, they're just expensive (but pretty)!
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Old 02-06-2002, 05:07 AM
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If I recall correctly, they are also a higher ratio than the stock ~1.3 ratio rockers.

Lotsa money for very little gain. Probably should only be used if they are needed, if you're running really high RPMs and/or really need the ~1.4 (??) rocker ratio.

--DD
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Old 02-06-2002, 09:44 AM
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Pauter's rockers are 1.48 ratio which means if the cam has 0.450 inch lift with stock 1.1 ratio rockers, it will go up to 0.598 inch with 1.48 ratio rockers. The duration will also change and in all probability the valves will hit the pistons! The idea is to use a cam with a lower lift and easy ramp up, type 1 lifters for lightness, steel push rods, dual springs with titanium retainers and the engine can rev pretty easily. Mine does, but I tend to run it hard enough to break the valves off! I think that was due to setting valve clearances cold and the cam manufacturer said to set them hot, so now we do the adjustment hot. Hey Dave, are you going to Dunkle's this weekend? Good luck.
Old 02-06-2002, 05:35 PM
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Thanks for all the info guys. These things are out of my league
I think I'll only go rollers if I build a big V8 for an american muscle car some time in the future.

Nathan
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Old 02-06-2002, 05:58 PM
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The ratio rockers are splash oilers, not self oilers, like stock...They should be saved for competition engines that are always turning RPM.

Most TIV cams have the wrong ramp rates for ratio rockers!
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Old 02-06-2002, 08:56 PM
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I believe that stock rockers are very close to 1.3:1 ratio. (I've also heard that the intakes and exhausts are a little different, one is just below 1.3:1 and one is just above 1.3:1 .)

I'm trying to make Dunkel's this weekend, but it's not looking very good. I've got that nasty flu that's been going around, and I'm not at all sure I'll be able to get over it enough to head down.

--DD
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Old 02-07-2002, 08:06 AM
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D.D.D.D. is a WUS.S.S.S.

a few 911 hot wings from Hooters will fix that flu right up!..

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Old 02-07-2002, 09:44 AM
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Jeff, please allow me to quote from the inimitable Mike Z:

"Bite me."



Actually, have your sister come over and bite me!!

So much for Ginter's 'cados... Unless Jenny wants to deliver 'em.

--DD
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Old 02-07-2002, 10:21 PM
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Thumbs up Daves got the flu

hummm, lets see, SUNNYvale Cal. no snow, no ice , no below freezing temps, why should we feel sorry for Dave???????????
Go this week end and post lots of pictures.

Old 02-08-2002, 01:55 AM
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