Solid Vs. Hydraulic!!! Which is better?
69NovaKid
05-05-2009, 02:08 PM
Hey everyone- im sure this has been asked many times before, but as far as a street strip vehicle- which is better a solid cam of a hyrdaulic flat tappet? Currently i have a hydraulic flat. from lunati in a 355 sbc. specs are 480/480 lift 232. duration 109/107 - I wanted to change the cam to a solid - but arent sure what the best way to go is. Edelbrock Performer RPM heads with 1.6 ratio roller rockers- 3.42 gears- 2,500 stall. please help!
toddman67
05-05-2009, 06:44 PM
I'm have a similar set up and with the 1.6 ratio rockers you are getting .512 lift. That said changing to another cam with a greater lift, you will need to know if the valve springs will take it without binding. Also try to keep the duration low or you will have a hard time keeping the ilde in check for street use. I experienced problems and switched over to a eldebrock performer carb and bought the jet kit and springs to make it run good. I guess it all comes down to your preference and what the rest of your engine can handle.
toddman67
05-05-2009, 07:59 PM
If you're looking to get more out of your engine. put some more gear in the rear end. 373's or 411's. that will spark it up!
MrPbody
05-06-2009, 08:26 AM
Novakid,
To answer your question, it is accepted that solid lifters are ultimately better for power production than hydraulics. This is due to a variety of reasons. Mainly, the "positive" valve action of the solid makes for a predictable and stable open/close cycle. "Lift" is not "theorhetical" as it is with hydraulics. Also, iof your springs are "up to it", solids DO NOT "float". NOTE: A change of springs will likely be necessary.
We've been using Comp's XE grinds in small blocks of late, with the "drilled" solids. WOW! They make incredible power. XS274S seems to be among the better ones with "mild' heads. Very streetable, it will make that 355 a BEAST above 3,500, and still have good low-end for driving. It SHOULD be okay with that 2,500 converter, too. if you DO choose a Comp XE grind, let Comp o the engineering, do NOT deviate from their specs.
I would recommend the installation of oil restrictors if you go to the solid.
Agreed with Todd, changing the gear is called for. The 3.42 is much better with larger, higher torque engines. 3.73 is ideal for the 355.
Jim
To answer your question, it is accepted that solid lifters are ultimately better for power production than hydraulics. This is due to a variety of reasons. Mainly, the "positive" valve action of the solid makes for a predictable and stable open/close cycle. "Lift" is not "theorhetical" as it is with hydraulics. Also, iof your springs are "up to it", solids DO NOT "float". NOTE: A change of springs will likely be necessary.
We've been using Comp's XE grinds in small blocks of late, with the "drilled" solids. WOW! They make incredible power. XS274S seems to be among the better ones with "mild' heads. Very streetable, it will make that 355 a BEAST above 3,500, and still have good low-end for driving. It SHOULD be okay with that 2,500 converter, too. if you DO choose a Comp XE grind, let Comp o the engineering, do NOT deviate from their specs.
I would recommend the installation of oil restrictors if you go to the solid.
Agreed with Todd, changing the gear is called for. The 3.42 is much better with larger, higher torque engines. 3.73 is ideal for the 355.
Jim
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