I've been reading lots of threads where they start off with "I got this engine and I want this much HP" I think this is the wrong way to go about it. Which is funny because I got a thread "400+HP 273" but before I'd desided on the 273 I thought about every engine combo for my ride if I wasn't running in Time Attack (solo 1) I'd run a 500+ cid engine. The reason for picking the 273 was that I need 400HP with a 2000-7000 rpm powerband any more power than that I'll be running with Vipers with my 1965 Cuda.
Race engines and street & strip engine specs will mainly be desided on the class that you run but a street & strip will have to be a little more reliabile than one run at a time.
1st thing to deside is how streetable you want you ride and streetable means different things to different people but it mainly comes down to reliability, how often you want to tear into your engine (weekly, monthy, yearly or decades) which has to do with how often you run full out and at what RPMs
and how many miles you'll put on your ride. A decent built engine will have about a 5000 RPM powerband a race engine can narrow the powerband for more peak power.
RV idle-5000 or less .7-.9 HP per cid
Street Idle-5500 1 HP per cid
HiPo Street 1000-6000 1.1 HP per cid
Hot Street 1500-6500 1.2 HP per cid
Street&Strip 2000-7000 1.3 HP per cid
Obviously this genralized but get you in the ballpark.
2nd thing you should deside is power ratio to weight (P/W) and curising RPM
which includes final trans gear, rear gear, and tire size. A lot of people automatically think smaller engine gonna give you better gas mileage but smaller engine need more gear than larger engine, especially if you want a fast car so a smaller ones gonna turn more RPMs than a larger one and burn similar amount gas (mpg) for the similar amount of acceleration. A heavy auto car gonna need more gear than a lighter standard car, a car with a good P/W ratio and a lower RPM band gonna need a lot less gear.
Once you desided on your powerband, P/W and gearing that gonna shape your engine specs some compromises are gonna be made especially on a budget. Let say you have a Duster 3200-35000 pounds with driver and want Street level preformance with an 1 to 6 P/W 3.23 gears with 0.70 automatic overdrive and 25" tires. Thats 533-583HP and at 1 HP per cid would obviously be 533-583cid so a 540 stroker be your choice and would cruise 1800 RPMs at 60 MPH. A lot of engine for this power level, could do it with a lot less but this combo would make an great daily driver and be rock solid and very fast.
Spec'ing the engine so now you got a ballpark idea of what you need,
1st thing head choice you'll need about 2 cfms per HP @ 28" 266-291 cfms.
2nd cam choice enough lift to go with your heads and duration to go with your powerband, gearing, compression ratio, stall speed and cruising rpm.
3rd carb, intake, headers and bottom end to support your power level and powerband.
I know this is long but thats the way I see it and hopefully this helps some of you out, I'm by no mean an expert if other see something I missed or thats incorrect by all means add.
Race engines and street & strip engine specs will mainly be desided on the class that you run but a street & strip will have to be a little more reliabile than one run at a time.
1st thing to deside is how streetable you want you ride and streetable means different things to different people but it mainly comes down to reliability, how often you want to tear into your engine (weekly, monthy, yearly or decades) which has to do with how often you run full out and at what RPMs
and how many miles you'll put on your ride. A decent built engine will have about a 5000 RPM powerband a race engine can narrow the powerband for more peak power.
RV idle-5000 or less .7-.9 HP per cid
Street Idle-5500 1 HP per cid
HiPo Street 1000-6000 1.1 HP per cid
Hot Street 1500-6500 1.2 HP per cid
Street&Strip 2000-7000 1.3 HP per cid
Obviously this genralized but get you in the ballpark.
2nd thing you should deside is power ratio to weight (P/W) and curising RPM
which includes final trans gear, rear gear, and tire size. A lot of people automatically think smaller engine gonna give you better gas mileage but smaller engine need more gear than larger engine, especially if you want a fast car so a smaller ones gonna turn more RPMs than a larger one and burn similar amount gas (mpg) for the similar amount of acceleration. A heavy auto car gonna need more gear than a lighter standard car, a car with a good P/W ratio and a lower RPM band gonna need a lot less gear.
Once you desided on your powerband, P/W and gearing that gonna shape your engine specs some compromises are gonna be made especially on a budget. Let say you have a Duster 3200-35000 pounds with driver and want Street level preformance with an 1 to 6 P/W 3.23 gears with 0.70 automatic overdrive and 25" tires. Thats 533-583HP and at 1 HP per cid would obviously be 533-583cid so a 540 stroker be your choice and would cruise 1800 RPMs at 60 MPH. A lot of engine for this power level, could do it with a lot less but this combo would make an great daily driver and be rock solid and very fast.
Spec'ing the engine so now you got a ballpark idea of what you need,
1st thing head choice you'll need about 2 cfms per HP @ 28" 266-291 cfms.
2nd cam choice enough lift to go with your heads and duration to go with your powerband, gearing, compression ratio, stall speed and cruising rpm.
3rd carb, intake, headers and bottom end to support your power level and powerband.
I know this is long but thats the way I see it and hopefully this helps some of you out, I'm by no mean an expert if other see something I missed or thats incorrect by all means add.
