question for engine builders
iroczman
08-24-2005, 02:30 PM
is .030 over on a 350 a 355?
And how can i get 375 hp and 400 and over ft/lbs out of a 355 carburated? thinking a rv cam
And how can i get 375 hp and 400 and over ft/lbs out of a 355 carburated? thinking a rv cam
ct91rs
08-24-2005, 07:36 PM
is .030 over on a 350 a 355?
And how can i get 375 hp and 400 and over ft/lbs out of a 355 carburated? thinking a rv cam
Yes, thirty over would give you a 355 cid engine.
Displacement = # of cylinders x .7854 x bore^2 x stroke
8 x .7854 x 4.03^2 x 3.48 = 355.116 cid
About the hp. It's possible, but without a shot or forced induction, your probably looking for some good heads/intake/carb/headers-dual exhaust to find those numbers.
And how can i get 375 hp and 400 and over ft/lbs out of a 355 carburated? thinking a rv cam
Yes, thirty over would give you a 355 cid engine.
Displacement = # of cylinders x .7854 x bore^2 x stroke
8 x .7854 x 4.03^2 x 3.48 = 355.116 cid
About the hp. It's possible, but without a shot or forced induction, your probably looking for some good heads/intake/carb/headers-dual exhaust to find those numbers.
blindeyed
08-24-2005, 09:04 PM
Yes, thirty over would give you a 355 cid engine.
Displacement = # of cylinders x .7854 x bore^2 x stroke
8 x .7854 x 4.03^2 x 3.48 = 355.116 cid
About the hp. It's possible, but without a shot or forced induction, your probably looking for some good heads/intake/carb/headers-dual exhaust to find those numbers.
How did you come to get ".7854?" The equation I use when I figure my numbers is: (3.14)(bore²)(stroke)(#cylinders). Because to get the volume of a cylinder, don't you need (3.14)r²h, then multiply that by the number of cylinders? Just kind of curious as to how you came with that. Because when I put in his bore & stroke on mine, I came with 352.29 ci. Am I doing this wrong?
Displacement = # of cylinders x .7854 x bore^2 x stroke
8 x .7854 x 4.03^2 x 3.48 = 355.116 cid
About the hp. It's possible, but without a shot or forced induction, your probably looking for some good heads/intake/carb/headers-dual exhaust to find those numbers.
How did you come to get ".7854?" The equation I use when I figure my numbers is: (3.14)(bore²)(stroke)(#cylinders). Because to get the volume of a cylinder, don't you need (3.14)r²h, then multiply that by the number of cylinders? Just kind of curious as to how you came with that. Because when I put in his bore & stroke on mine, I came with 352.29 ci. Am I doing this wrong?
ct91rs
08-24-2005, 09:56 PM
pi/4
I came across it one time, and it eliminates cutting the bore (diameter) in half to come up with the radius. But if you don't remember the number, it's just as much work.)
Displacement = # of cylinders x pi x bore radius^2 stroke
8 x 3.141 x 2.015^2 x 3.48 = 355.1152
or
Displacement = # of cylinders x .7854 x bore^2 x stroke
8 x .7854 x 4.03^2 x 3.48 = 355.116 cid
I came across it one time, and it eliminates cutting the bore (diameter) in half to come up with the radius. But if you don't remember the number, it's just as much work.)
Displacement = # of cylinders x pi x bore radius^2 stroke
8 x 3.141 x 2.015^2 x 3.48 = 355.1152
or
Displacement = # of cylinders x .7854 x bore^2 x stroke
8 x .7854 x 4.03^2 x 3.48 = 355.116 cid
blindeyed
08-24-2005, 10:07 PM
Ah, I see. Very ingenius, I would have never thought of that.
89IROC&RS
08-24-2005, 10:54 PM
AHH its off by .0008, you silly little rabbit.............
but anyway, the power figures youre looking at with an RV cam are probly pretty optamistic. id be looking at some vortec heads and a mild hydrolic roller cam with around .470in of lift. and moderate durration. check out hot rod magazines, or chevy hi performance magasines "agent 87" it was a low buck 355 with vortec heads that ran 408hp and about 400ft/lbs of torque.
but anyway, the power figures youre looking at with an RV cam are probly pretty optamistic. id be looking at some vortec heads and a mild hydrolic roller cam with around .470in of lift. and moderate durration. check out hot rod magazines, or chevy hi performance magasines "agent 87" it was a low buck 355 with vortec heads that ran 408hp and about 400ft/lbs of torque.
iroczman
08-25-2005, 03:11 PM
thanks guys.
Morley
08-26-2005, 01:59 AM
375 on a carbed engine is easily obtainable, the torque figure you are looking for, you probably won't get or just barely make 400. For torque you can't beat TPI.
Go with 9.5:1 compression, some nice alumnium heads (ported 113 corvette heads would do), a good cam kit, single plain intake manifold, a quadrajet carb (yes a quadrajet..I'll explain later) headers and a good freef lowing exhaust (doesn't have to be duals, a good 3" single will work just fine)
The reason I say quadrajet is that they have small primaries which will get you some decent fuel economy. but the secondaries are absolutely huge, for that quick launch or passing. And they are very reliable. I've personally had nothing but trouble from Holley carbs, that and everyone wants a 750 double pumper...this is just plain too much carb for any small block that isn't an all out race engine.
Go with 9.5:1 compression, some nice alumnium heads (ported 113 corvette heads would do), a good cam kit, single plain intake manifold, a quadrajet carb (yes a quadrajet..I'll explain later) headers and a good freef lowing exhaust (doesn't have to be duals, a good 3" single will work just fine)
The reason I say quadrajet is that they have small primaries which will get you some decent fuel economy. but the secondaries are absolutely huge, for that quick launch or passing. And they are very reliable. I've personally had nothing but trouble from Holley carbs, that and everyone wants a 750 double pumper...this is just plain too much carb for any small block that isn't an all out race engine.
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