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Munch Munch Rice 4 Lunch
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594 Posts
Discussion Starter #1
well just from reading on the forums got me thinkin, solid cams use solid lifters hydraulic cams use hydraulic lifters pretty straight forward so far, but can roller lifters be used with a hyd or solid cam? if so wouldn't they be a good option for those running high performance valve train?
 

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Munch Munch Rice 4 Lunch
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594 Posts
Discussion Starter #2
by the way i was considering this for a 351clevo rebuild.
and another thing are windsor roller rockers the same as clevo i saw ones advertised in parts peddler for 351 windsor that were 1.71:1 ratio so does that mean they'll fit... i'm confused
 

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Whats traction?
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2,197 Posts
Its not something I've heard of being done, I would say at a wild, barely educated guess that yes it would work... but if your spending all the money buying the roller lifters then why not get a cam to suit?

Also you'd be missing out on the major benifits of a roller cam and that is the lobes are shaped differently to take advantage of the constant contact between the roller and the cam lobe. The cams are ground with the mid-lobe area larger than the hydraulic for this reason.

A hydraulic cam needs to push the oil pressure up to get the valve to open fully at the lobe peak so its mid-lobe area is designed to do that, the roller cam is instead designed to give more lift in the mid lobe area, thus the valve is open wider during the ramp up and its action is much smoother too.

In an article I was reading recently from the US they swapped a flat-tappet cam to a nearly identical spec roller cam and shaved 0.3 of their quater mile time and noted much better low-mid range power. After that they swapped the Victor Jr manifold with a Weiand and sliced another 0.2 second off their quarter. Half a second for a cam and manifold swap is damn good if you ask me!

Apologies for the long post....
 

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Two SC 61's = trouble
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6,360 Posts
Flat tappet cams are generally ground with slight angle to make lifter turn, while roller cams are straight, square..Pluss the lift and ramps on roller cams are generally too steep for flat tappet.Keep to what they're designed for...This part of the engine takes a beating and often what stuffs up initially...
 

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Munch Munch Rice 4 Lunch
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594 Posts
Discussion Starter #6
do they make roller cams for clevo's, i thought it was something that the block had to be machined to take, unless it was like the late model windsors that are already setup for roller cams.
 

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yes there are roller cams for clevos and conversion kits for the lifters the spider as its called simplly ataches to bolts you tap in the drain holes sitting inside the lifter valley, the spider is cheap the lifters and cam are expensive compared to a hydraulic, vpw probably best ppl to talk to if u dont have a trade account elsewhere.
 

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xdc351 said:
In an article I was reading recently from the US they swapped a flat-tappet cam to a nearly identical spec roller cam and shaved 0.3 of their quater mile time and noted much better low-mid range power.

I had to register just so I could add something to this from my personal experiance. That sounds like a bogus article, unless they had a really lousey flat tappet cam.
Here's why I think this; A couple of years back, I sheared the pin in the front of the cam on my solid roller camshaft. Since I was in the midst of a points battle, we fixed it, but put a solid flat tappet cam in instead. The specs were similar. The solid roller was 264/272 duration @ .050, .650/.650 lift, 108 lsa and used .026/.028 lash. The solid flat tappet was 266/277 duration @ .050, .625/.623 lift, 107 lsa, and used .022/.024 lash. With the solid roller the car ran low 6.40's in the 1/8 in the heat of the summer (the last full pass with the roller it ran 6.43.) When I put the solid flat tappet in, I expected it to slow down a bit. First pass with the flat tappet cam, it ran 6.43. The 60' time was the same as was the mph.
 
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