ok i been thinking about this... no bore... stroke... wouldn't it take longer to whind up?.... yeah, it would make better overall power... but wouldn't it loose 0-60??

i dunno... enlighten me...


i mean.. thats why some people DE-stroke 350's... don't they?

 

Any engine that is stroked will give much better low end torque. Weird cam configurations being the exception. Torque is what gets you off the line so a stroked engine with all else being the same will jump off the line faster than a stock stroke.

Phew say that 3 times fast.

 

a stock bore with a 3.75 crank is a 377, to go 383 you need to bore the motor .030 over thus making it a 383 more stroke gives the crank more leverage in which to push the piston up, giving the engine more twisting force (tq). Enlarging the bore will also give you more tq along with hp and compression. The motor in all actuallity might rev a tad slower, but the low end tq you gain will MORE then make up for it. and if you cam the motor right it will have the power in the appropriate places

 

If that was the case, wouldn't we all want 1.0L honda engine .

 

The usual statment at this point is:
There's no replacement for displacement.
And hell no i wouldn't want a 1.0L

 

The 383 can make good power.

With a more "stock" induction system you'll see alot more torque but not a whole deal more horsepower. If you want to push alot of hp, you just need the right heads, intake, cam, etc..

-Mindgame

 

tq is what moves your car. HP isnt near as important... horsepower in a choppy deffinition is the engines ability to make tq readily.. so kinda how fast the engine can make tq in a way.. a High tq motor IE big block will be faster in most cases then a lower tq higher reving motor ie Small block.. obviously not in all cases.. but TQ is what moves you.. especally off the line

 

You can't really seperate one from the other. Two similar motors in identical cars, the one with more hp is gonna make it to the end of the track quickest. You simply move the torque up the rev band and gear the car accordingly.

-Mindgame

 

more hp dosent always make the car get there faster.. Tq is very important.. this is drastic but if i have 1000 hp and 200 ft lbs of tq.. something with 600 hp and 600 ft lbs of tq will be faster depending on how the cam is set up and what not... HP isnt always the most important thing in the world people always disregaurd TQ and its also a very important factor.

 

Not to turn this into a hp vs torque thread but I can think of numerous times I've seen the car with more HP vs the one with more TQ but less HP win the race..... this seems to happen more than the opposite actually.

Take an L98 Vette and put it up against an LT1 Vette. Same trannies, same gearing, same weight... very imuch identical. Now consult some old Road and Track magazines or whatnot cause the LT1 Vette was consistently quicker.... same goes for LT1 vs LT4 Vette.
The L98 makes 250 hp @4000 rpm and 340 lbs-ft @ 3200, the LT1 is 300 hp @ 5000 rpm and 340 lbs-ft @ 3600. Launch both cars at the same rpm and the LT1 Vette will progressively put more space between itself and the L98. It has another ~1000 rpm in which to accelerate before each shift. You could draw the same comparison between the LS1 and LT1 camaro. The more gears you have to work with (the tighter the spread), the higher the torque peak can be. A peakier engine can actually make for a faster trip down the strip in this case.
What would be even more important is the torque curve in the rpm range that is relevent to a drag race..... or a road course.... doesn't matter. It's all about gearing. So the question is..... torque where?
Having drag raced on a competetive level for some number of years I can tell you that the guys who make the most hp only worry about torque where it's relevent to the combination.... tranny, gearing, and rpm is where it's at.

"Most torque" doesn't mean much by itself. As I said you can't seperate one from the other. Torque at higher revs... I'll take that.

-Mindgame

 

Well said. Anyone who has ever driven a diesel will appreciate the limitations of a motor that makes a lot of torque at low rpm but can't rev.

Bonus question (answer to follow, no prize to winner): If two motors in identical cars had identical torque and hp curves, but the curves were "offset" a couple of thousand rpm apart, and gearing could be optimized for each combo, which would be faster? The one with the higher rpm rnge or the one operating lower?

Rich Krause

 

The higher one. Because when you shift, you always take it up to redline, or close to that. Well, lets see if I'm correct.

 

thats kind-of a trick question

it depends on the shift points
traction suspension
auto or manual
what size converter
weight of each car
hp and tq split
drag co-eficent

and the motor whose hp and tq is down low is more efficent if it they are the same

the one who's hp is lower may be quicker while the one who's hp is up higher is faster

 

It wasn't intended to be tricky. Ignore traction. Consider the hp and torque as measured at the rear wheels and the transmission are the same excpet gearing is optimized.

Rich Krause

 

well then

letz say their both 3300 lbs and have a th350 3000 10 inch converter
then gearing is optiumized(sp) for indavidual hp

the one with a lower peak