David Vizard, Uncle Tony's garage, Unity motorsport. Mission impossible Dodge 302 Head porting
If that is the case, my car is pretty fast, for under 450hp
What's your combo ?
What rpm do you think you peak?
You can guesstimate hp reasonable well if your good at guesstimating these two things peak torque and hp peak rpm.
Torque is fairly easy since it's heavily reliant to displacement, most of us don't build over 1.3:1 lbs-ft per cid so more amateur and or less then ideal parts 1-1.9:1, decent builders 1.2-1.2.9:1, pro builders 1.3-1.39:1, top 1% er builders 1.4-plus:1 .
So I generally use 1.15:1, 1.2:1, 1.25:1 depending what I feel the level of the build and builder or 1.175:1 for an all around general number if not much is known.
So cid x lbs-ft per cid = engine peak torque or just guess how much peak torque you make.
Torque at peak hp is generally 90% ish so peak torque x 90% = torque @ peak hp, now you just need to guess peak hp rpm or where does it feel where it peaks, and just plug the numbers into the hp formula, hp = torque x rpm / 5252,
So say you think you make 420 lbs-ft which is 378 lbs-ft at peak hp say at 5300 rpm, 378 x 5300 \ 5252 = 381 hp. And peak torque is generally 1000-2000 rpm lower,
381 hp @ 5300 rpm
420 lbs-ft @ 3700 rpm
