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question about using cams with roller rocker set-up


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so my car has roller rockers and (i suspect) a stock cam.

 

do the roller rockers affect cam specs, or can I use any cam that I would normally want to use with standard slider rockers?

 

like, if I wanted to run one of tim's cams, would it have to be special in order to work with the roller rockers?

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Using a roller rocker on the stock slipper cam will actually give you less duration. On the stock cam I also highly doubt that your lifter preload is enough. I played around with a few cams, roller and slipper grinds. Also tried 1.5 and 1.6 ration rockers. As far as I have seen it's not possible to "correctly" run roller rockers and get the proper hydraulic lifter preload with the late model (shorter) valves without running some kind of lifter shim. There's more to it but that's the gist of things. It may run fine but you likely aren't getting the most out of it.
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Some info here, copied and pasted from Starquest.i-x.net SOS manuals:

 

Is a ROLLER a ASSET to performance? Only if you have a REAL-DEAL ROLLER PERFORMANCE CAM http://starquest.i-x.net/images/smiles/icon_exclaim.gif That SHORT RADIUS on a ROLLER WHEEL will cheat you outta DURATION TIME/DEGREES. http://starquest.i-x.net/images/smiles/icon_rolleyes.gif

 

And....that ROLLER WHEEL is SPLASH LUBRICATED ONLY http://starquest.i-x.net/images/smiles/icon_exclaim.gif Without a REAL ROLLER CAM PROFILE, YOU BEAT THE s*** OUTTA YOUR ROLLER WHEELS & LOBES http://starquest.i-x.net/images/smiles/icon_exclaim.gif

http://i35.photobucket.com/albums/d182/Professor-Quest123/Heads/RS-24B.jpg

 

http://i35.photobucket.com/albums/d182/Professor-Quest123/Heads/RS-24BA.jpg

 

-N8

Edited by natallica
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It won't hurt anything to run the roller rockers, but as others have already said, you lose duration. Certain roller rockers add a bit more lift that some say makes up for the initial loss, but I don't think it is a good idea to put a roller rocker on a non-roller cam for the most part.

Now Brian had good success with his performance grind slipper cam and roller rockers, but it was not a stock cam. It depends on the grind characteristics, but generally, a cam ground for roller rockers is needed to get the advantage that the rockers bring.

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So is the cam that comes on the Magna any good in our engines. I have a full set of rollers and the Magna cam sitting on the shelf. Right now I run slippers with mechanical adjustment.

A while back I got some specs on the cam from the magna and it was basicly same specs as the stock slip rocker (when using the rollers) Maybe slightly better then stock because or rollers but no gain in duration or lift

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stock magna rockers are 1.5 to 1 , useing 1.6 v6 roller rockers give some duration increase and a slight lift increase

eather way you should see a power gain from useing roller rockers if properly set up due to the less turn resistance it makes to the engine , turning the engine by hand there is a noticeable diff in effort required

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  • 9 months later...
Soooo....if running roller 1.6 ratio rockers, a roller cam (such as a Magna) without going crazy with custom grind cams, should be used?
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Id bet most of that "slight" lift increase from the rollers gets absorbed in lifter compression.

 

Has anyone done any REAL roller cam testing? Benefit behind a roller is the better/more aggressive lobe profile that can be had. Slapping it on a slip cam is kinda pointless IMO.

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I've been running a magna roller on my flatty for a couple of years, as has been said it has the same specs as the stock cam/slipper rocker setup but it does seem a bit smoother. The 1.6 ratio was too high though, it held the valves open enough to give 70% leakdown, I had to switch to the 1.5 roller ratio to make it work.
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I've been running a magna roller on my flatty for a couple of years, as has been said it has the same specs as the stock cam/slipper rocker setup but it does seem a bit smoother. The 1.6 ratio was too high though, it held the valves open enough to give 70% leakdown, I had to switch to the 1.5 roller ratio to make it work.

 

Thats good info. Dod you notice an increase in vacuum?

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I really need to get my Monsta Banshee roller cam setup in my car one of these years...

Maybe I can get that dialed in and have the 284 slipper setup on a rocker assembly ready to switch out quickly on a dyno day for comparison... sounds good but it probably won't happen

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so is the 1.6 rockers a bad idea with a stock cam? I am thinking of installing a cam and don't know what to go with any suggestions?

 

Yes don't use rollers on a stock cam.... rollers are for roller cams.

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I was looking at these last night 284h i was really looking at but wanted to see everyone's feed back

http://schneidercams...amshafts-2.aspx

 

That is for regrinding your cam. I guess what are your goals? Have you upgraded everything eles first? It's not going to be like say an LS where you just recam it and the car just wakes up.

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