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yeah yeah, hyd roller may be for girls or w/e, but it is alot nicer on the street in a daily driver thats for sure. and i hear they make better bottom end torque
 

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The engine is a 355 with a stock GM block- 13 to one compression-modified 850 Holley on a super victor- the two cams were 276-286 at o50, both on 106 centers- Roller cam made 616 at 7700. flat tappet made 559 at 7600- AFR 210 heads ( ported ) two inch headers- That is all I can say about it

JOE SHERMAN RACING ENGINES

Those are pretty big duration cams.
Have you performed similar tests with the duration around 240 or so?
I could be wrong but I would suspect that at lower durations, the solid roller has less of a dramatic differnece.
 

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Discussion Starter #25
You are right about the longer duration making a bigger gain-- When the hyd rollers came along about 15 or 20 years ago, I did a test on hyd flatt to same duration hyd roller. I cant remember the exact duration , but like 240 at 050- the roller was only 7 or 8 HP better at a cost of 600 dollars more-- Not a good deal. Much later i have run the more modern Comp Cams grinds, and the same duration is worth 20 to 25 more than the flat lifter with the same duration- The solid lifters, flat or roller , do not out perform the hyd very much untill you rev up past 6000 RPM. The higher you go, the bigger the differance will be. By 7000, it could be as much as 50 HP, at 7500, it could be 100 horsepower

JOE SHERMAN RACING
 

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Joe, since you have performed so many dyno tests and engine builds, I have a question for you.
Lets say a 400 inch small block (4" bore, 4" stroke) like one of you windsor strokers has a 235 @ .050 on 110 LDA hyd roller. 10.5 compression.
It makes good smooth low end and revs to about 6K.
If you replace that cam with a 245 @ .050 solid roller, can it then make power up to 7K and not lose any low end drivability (and still pick up 50 hp)?
 

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I would have to agree that unlimited (unrestricted) classes can benefit significantly from rollers, but lift-limited or duration-limited scenarios or classes can often see flats easily outrun rollers. There are too many situations to make flat (no pun intended) statements that one type is always better.

David
 

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I would have to agree that unlimited (unrestricted) classes can benefit significantly from rollers, but lift-limited or duration-limited scenarios or classes can often see flats easily outrun rollers. There are too many situations to make flat (no pun intended) statements that one type is always better.

David
Very accurate statement David..... and it needed to be said.

People read threads like this, get all excited and think they are going to gain 60hp from going from solid FT to a similar solid roller. BUT ... like you state, actual results is going to depend on application.... and not to mention combination.
 

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Very accurate statement David..... and it needed to be said.

People read threads like this, get all excited and think they are going to gain 60hp from going from solid FT to a similar solid roller. BUT ... like you state, actual results is going to depend on application.... and not to mention combination.
X3. One shouldn't overgeneralize.

paulie
 

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I don't really agree that hyd rollers are that "*****".
They have their place.... and from our experience, in most situations a "milder" hyd roller will match a slightly "hotter" solid roller hp wise.... meaning comparing cam to cam, you need more duration/lift from a solid roller to match the performance of hyd roller. Think about it, a hyd cam has a big head start over a solid.
Alot of people will say that that is b/s .... They will also tell hyd lifters are so much heavier too, but directly comparing apples with apples (i.e a performance link-bar hyd to link-bar solid) they are only around 15gms heavier. Think about a solid roller lifter, it is around 40 grams heavier than a solid flat lifter....
I think the biggest "issue" with the hydraulics is perhaps the actual lifter performance and cost.... like everything else, there are the "cheap" ones and the good ones. And the good ones certainly aren't cheap....

Like all things, there are compromises to be made but if you have a street or street/strip deal thats not getting turned to "excessive" revs and "have to have" a roller.... why not hydraulic?
If nothing else, it will be easier on the valvetrain...
 

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Great information coming from you, Joe! I, for one, am a true believer in your ability to extract horsepower, after reading the dyno sheet on the iron headed 396 you recently built for Dave Henry, which is back in my shop for its final round of metal work. I for one cannot wait to see his grin when he puts this powerplant to work!!
 

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Joe - any way we could see some average hp/tq numbers? Or even comparative dyno sheets? Peak numbers tell little of the whole story - unless we're racing dyno's. ;)

David
 

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Great information coming from you, Joe! I, for one, am a true believer in your ability to extract horsepower, after reading the dyno sheet on the iron headed 396 you recently built for Dave Henry, which is back in my shop for its final round of metal work. I for one cannot wait to see his grin when he puts this powerplant to work!!
Great information coming from you! I, for one, am a true believer in your ability to extract horsepower, after reading the dyno sheet on the iron headed 396 you recently built for Dave Henry, which is back in my shop for its final round of metal work.
Huh?
 

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Hhhmm and now greg23 or his post ... don't exist ??
I smell something ....
Whats happening admin ??
 

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A few days ago I ran a SB Chevy where we tested camshafts-- The same duration at 050 and 200 lift-- The roller camshaft made 57 MORE HP at the peak, and 33 pounds more torque at the peak- I am showing this for any of you who think than a flat tappet is sort of close to a roller ---WRONG-- The only time a flat tappet is close to a roller is when it has 25 or 30 degrees more duration

JOE SHERMAN RACING ENGINES
Solid Roller is the only way to go. Hyd roller for guys who don't like foolin' with their cars, and messing up valve covers with oil. Once u drive Solid Roller u'll never go back. Only maintenance is valve lash every 6 months or so.

If it's mainly street car, then go with Comp Cams Solid street roller series, they have gentle ramp rates and r designed to be easy on roller lifters and valvetrain components, plus the cam is cast so u can use steel gear for Dist, and ur street longevity will be way longer compared to regular race solid roller. Spring pressures r less also which is good for lifters. Comp has new Elite Solid Roller lifters coming out in late December early Jan of 2010, supposed to be 50% better than Endurex and best Solid Lifter on the Market.
 

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Solid Roller is the only way to go. Hyd roller for guys who don't like foolin' with their cars, and messing up valve covers with oil. Once u drive Solid Roller u'll never go back. Only maintenance is valve lash every 6 months or so.

If it's mainly street car, then go with Comp Cams Solid street roller series, they have gentle ramp rates and ...
That's all generally good advice, and not to twist your nipples, but the question was solid flat vs. solid roller and was the basis for Joe's quote you used. While I usually use and generally recommend rollers, there are some situations where flats can perform better, especially when faster flat lifter acceleration can be used to advantage. These situations are not entirely common, and not likely the type of engines that Joe tends to produce on a daily basis. I doubt Joe makes many - if any - engines that fall into that category, and for him, solid roller is king. That's fine, but doesn't always apply to everyone, nor every situation. Use what will work best for the specific application. There's your answer. If it's not critical enough to do the homework on each type and evaluate the pro's and con's of each for a certain application, it's probably not important enough to worry about. Just go roller.

BTW - you simply cannot directly compare flat and roller cams on a dyno without producing special grinds to make an empirical comparison. With computer software geometries can be evaluated for benefits that won't show-up until it's on the dyno. Without those minimally required comparisons no favor can be placed on one or the other, except in a general sense or by personal gut-feeling opinions. Example - for very high relative lifts and durations at relatively high RPMs, the solid roller will generally be at advantage. That's Joe's territory, and he does well with them.

By contrast, an example I alluded to earlier was a class limited (as most classes are) engine. We were working with Crane at the time, and were curious about a loophole in the rules that would allow rollers. Crane said that no roller grind would out-perform the optimized flat we were using. With lift and duration limits, we would have made a few more peak horsepower, but the flat (with it's faster initial valve acceleration) made more average power in the range it used. Bottom-line was that the flat - in that case - was faster than the roller on the course, although it would have looked better on the dyno with a roller. Horsepower peak wins sales. Horsepower average wins races.

David
 
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