Guess the horsepower

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flipper said:
Bought this , won't be able to run it til next summer , take a guess at horsepower just for fun
340 bored .020" over
10.5:1 speed pro hyperutectic pistons
Racer brown solid cam, .520 lift, can't remember duration but it's a lot
360 j heads fitted with 2.02/1.60 valves, ported and flow tested (255 from on intake)
Titanium retainers
Victor jr intake
273 rockers (adjustable)
Windage tray
I think the crank is turned .020" on both mains and rods
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Your Cam is ST-21. .520 lift on intake and exhaust with 286 duration- direct connection in 1978 catalog. I use this cam in my build back then with Torker intake,273 rockers, 750 cfm Holley, 4 speed transmission with 410 post end. Ran in mid 13's all day. But then in the 70's, was not bad. This was a street car. For Horse Power- around 450.
 
flipper said:
Bought this , won't be able to run it til next summer , take a guess at horsepower just for fun
340 bored .020" over
10.5:1 speed pro hyperutectic pistons
Racer brown solid cam, .520 lift, can't remember duration but it's a lot
360 j heads fitted with 2.02/1.60 valves, ported and flow tested (255 from on intake)
Titanium retainers
Victor jr intake
273 rockers (adjustable)
Windage tray
I think the crank is turned .020" on both mains and rods
Click to expand...
The engine will do the 7000 rpm.
 
I had a 450 lift cam and the rest similar. I was at 415. Still poked well past 120mph with 3:55's though and kept a good layer of rubber on the pavement.
 
My stock '71 340 made 375 on track fwhp with .039" gskts so prob only 9.8:1?, stock 2.02 heads, 850DP, HSD intake and the .590 purple solid, so I would say around 430hp....depends on how much those heads [email protected]"
 
I'd say around 600+..
Does that make you feel better?

Just bustin' your chops. :steering:
 
ZieglerSpeed said:
I'm the only 1 on earth that don't exaggerate horsepower. Headers? What carb? It's a winder!! To much duration'll kill it for torque
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Whatever.
Who cares about the torque(i suspect you are talking about that allmightly popular lowend torque not actual torque) ?
This thread is about horsepower.
 
ZieglerSpeed said:
I care about torque and when I pick a cam I don't throw my torque away...or I'd pick a cam that kept the valves open all day.
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Yeah but this thread is about horsepower,and as we all know the engine needsto make a bunch of torque to be able to make good horsepower..
 
Torque is a product of cubes and stroke but you can kill torque with poor cam/intake selection. The 1/4 mile is the test bed of the American muscle car. You don't want to be the slow example with your motor
 
ZieglerSpeed said:
Torque is a product of cubes and stroke but you can kill torque with poor cam/intake selection. The 1/4 mile is the test bed of the American muscle car. You don't want to be the slow example with your motor
Click to expand...
Irrelevant there is a reason hp is king and more rpm aloves you to add gear and get more torque to the wheel just add more converter get into the engines sweetspot.
this is not rocketscience. Feel free to let me know when your low rpm short camduration turd gets to the finnishline of that quartermile faster than a prostock car and i will start to take notes.

Back on topic wich is HP.
 
I'm not runnin a pro stock and I doubt you are. If you have a stroker ie: 360 or 440, high comp and a 4-spd or big stall, pour on the duration. You wind those strokers = slower time. 375 is the most accurate estimate on the big cam 340
 
ZieglerSpeed said:
I'm not runnin a pro stock and I doubt you are. If you have a stroker ie: 360 or 440, high comp and a 4-spd or big stall, pour on the duration. You wind those strokers = slower time. 375 is the most accurate estimate on the big cam 340
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Whatever this thread is still about hp,and hp with more rpm means ability to add more gear and therefore transfer more torque to the wheels regardless of the torque at the crank,a stroker is no different.
Also the more headflow the more camshaft can you run before you reach the point of diminishing returns(or expiring shortblock) and heads flowing 255 or so cfm on a litle 340 is enough to go quite far even if more flow would be nice.

Edit: Sorry if im coming of as an asshole here,have had a little to rough week and i think it has cut my patience way short for this.Hope you dont take it personal.
 
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ZieglerSpeed said:
the hey---it has to do with stroke. The TORQUE CURVE of a given motor dictating how high you wind it to get best time
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Yes,and if you add more cam you move that torque up in the RPM range. its a function of camduration/headflow/enginedisplacement not stroke.

No problem realy to run big cams in small engines,just need to get the complete package right. I have run more cam than the OP(and im not alone) in a stock stroke 340 and i used to have a very good picture of a pair of straight 150ft long black marks made by hoosier, made by just kicking that throttle pedal to the floor from a standstill,no lack of available torque where it was needed.

Regarding stroke,Previously before good flowing heads at reasonable prices came out people ran fast by turning more rpm due to more cam even if it didnt make much more power just because more gear made the difference,nowadays we have better heads and ability to somewhat cheap create more cubes thru strokercranks and people are making more power and dont need to spinn their engines as high to make good power but we are now back at square one,since the heads are again what holds us back and if you are headsup racing you will add more cam and gear on strokers aswell.

Btw hope you saw my edit to the previous post.
 
Your no asshole. We are just making points. I must add I'm talkin nothing wilder than stock elim or super stock. A point to ponder in which I'll point at the other guys cuz they are more extreme. Do you think a 454 stock/super stock is going to wind as high as a 265 (chainsaw)?
 
I had a very similar setup in my Duster back in he 80s but with the STX 21 and a Holley Strip Dominator. It was a 4 speed street car with only a pinion snubber in the way of suspension mods. It ran 12.31 in the quarter with slicks and uncapped headers at 109 mph running 5:13 gears. It weighed 3460 with me in it. I don't know what that calculates into flywheel horsepower but I'm sure there is a formula somewhere.
 
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