haha unless you come out western pa or me over eastern pa, i doubt we will see each other

but yeah you contact the right cam grinders you'll have LSx type lift on sbc cam. my hydraulic is over .600 lift with 1.6's

 

On one of the boards where some of the big name engine builders hang out they put the dividing line at 6500rpm as has been stated above. So below 6500 go hydraulic roller. Above 6500rpm that is where the solid roller starts to take over. But like Lloyd said be prepared for some maintenace.

Also you have to be carefull on which solid roller setup you get. Some do not like to idle below say 1100rpm because of oiling problems and the wear associated with not enough oil at low rpms.

 

I have a question: If this is true (and for sure it is..) , why solid roller needs to be at least one step more in duration compared to an hydraulic?
I read somewhere that a 230 range duration on an Hyd. roller should be compared to a 236 or 238 with SR.

-Beppe-

 

seat to seat timing (advertised duration) is lower on a SR due to the faster ramps (how much different depends on how aggressive the HR and SR lobes are).

SR's are based on CAM specs and diffeernt than what the valves see due to lash. HR cams will vary very little at the valve since there is no lash and only variation will be what happend in the lifter (bleed down, pump up, etc).

Will be a little variance dueto flex/deflection in PR, stud and rocker but with good parts, it is not a problem and is just part of the equation. SR cam that "should" have .688 (lobe lift x rocker ratio) will have less due to .016-.020 lash and the deflection of these parts so the valve might only open .650 or so. If you are not using a std girdle and have some aggressive lobes and lots of pressure, it will be even less lift at the valve.

A GOOD SR set up with a HP making cama nd springs will last 2 "seasons" of track use but put that same SR cama nd spring set up on the street for 2 years at 15K per year and see what happens to lifters, lifter bores, cam bearings, spring pressure, etc.

The cam and springs should be designed for the abuse (RPM and mileage) they are gonna see.

I LIKE setting customers up with the parts to make some power (SR with aggressive lobes, etc), I just wanna amke sure they are not expecting to have the same springs, lifters, etc, on the engine 30-50 K miles later. A milder lobe SR will allow this if they plan on doing this and getting away with lashing the valves once every 6-12 months (might still not even need it) and not swapping springs for 3-5 years but there are less HP gains to be had as well. At this point, a GOOD hyd roller is not gonna cost much HP at all and be even more durable with even less headaches.

As long as the guy buying the heads and cam for there car knows what they are in store, enjoys working on the cars, etc, no big deal. As mentioned, alot of LT1 owners (especially B body and Y body owners) need to understand there are some compromises and just because it is a SR doesn't mean an extra 50 HP and just because it is a HR doesn't mean you lose 50 HP.

It takes the aggressive lobes and GOOD springs, rockers, PR's, etc to see 50 EXTRA HP while sucking through 58 MM TB, LT1 intake LT1 heads, 1 3/4 headers and exhaust. The more restritions there are, the less gains you will see.

A cam swap that shows a 50 HP increase with some Pro Action heads, Super Vic intake, 850 DP, 1 7/8 headers and no exhaust will only show a 20 HP increase when having to suck through a CAI, 58 MM TB, LT1 intake, LT1 heads, 1 3/4 headers and exhaust system. That is just the way it is.

Lloyd

 

I gotta agree w/ Lloyd here. I've thought long and hard about this, did a lot of research, talked with a lot of knowledgeable people (first hand), and I've come to the conclusion that....Race = SR, Street = HR.

 

if you are wanting a serious set up, just stay away from catalog cams (Cc 306, etc) and go with someone that knows what they are doing on cams and you will have aggresive lobes, lots of HP and RPm from a Hyd Roller.