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i was looking around and noticed that the U.S. spec k20's have just over 140lb/ft of torque while the type r's from japan have between 150 and 160 lb/ft and then the us k24's have between 160 and 170lb/ft. I'm wondering what the noticable(if any) difference betweeen these torque numbers is?
 

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Horsepower is that buzzy sound that goes along in high revs. Torque is the feeling of being pushed back into your Recaros. You'll feel torque #'s way before horsepower #'s.
 

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i know what horsepower and torque are and i understand it. i'm just wondering how great of a difference is noticeable between those numbers i posted. Like you may not notice to great of a difference in first and second but what about like 3rd and 4th gear pulls? how great would you say the difference is?like is there a lot more noticable of a pull, or is it ever so slight of a difference, or is there definately a difference but nothing to big?
 

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i know what horsepower and torque are and i understand it. i'm just wondering how great of a difference is noticeable between those numbers i posted. Like you may not notice to great of a difference in first and second but what about like 3rd and 4th gear pulls? how great would you say the difference is?like is there a lot more noticable of a pull, or is it ever so slight of a difference, or is there definately a difference but nothing to big?
Yes
 

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i know what horsepower and torque are and i understand it. i'm just wondering how great of a difference is noticeable between those numbers i posted. Like you may not notice to great of a difference in first and second but what about like 3rd and 4th gear pulls? how great would you say the difference is?like is there a lot more noticable of a pull, or is it ever so slight of a difference, or is there definately a difference but nothing to big?
You listed a variance in yer first post of 30 ft.lbs. Yup I took into consideration you knew the difference between torq and ponies before posting. You'll feel a BIG difference in torq gains, especially in a game where one spends $$$$ for a few horsepower. You'll feel torq gains in any gear selected. You'll feel HP gains when at the end of each gears practical range.
 

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i know what horsepower and torque are and i understand it. i'm just wondering how great of a difference is noticeable between those numbers i posted. Like you may not notice to great of a difference in first and second but what about like 3rd and 4th gear pulls? how great would you say the difference is?like is there a lot more noticable of a pull, or is it ever so slight of a difference, or is there definately a difference but nothing to big?
Depends on the transmission and tire size. A stock K20A motor/tranny will pull harder than a K20A2 motor/tranny in the same chassis with the same tires. The K20A transaxle has a higher final drive.
On a motor dyno the K20A and K20A2 are very close. So is the K20Z1.
The K24 will make peak torque sooner, but it is fundamentally different. The longer stroke will ingest more air per RPM by design. Keeping it spinning safely is the key :up:
 

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Torque wins races, Horsepower wins shows

'nuff said
Oh really? When an F1 engineer designs an engine what do you think he strives for, having the most power or the most torque?
A Miata has almost as much torque as an S2000, infact it has a better torque/weight ratio.. why then is it much much slower in a straight line?
Torque wins races sure.... torque in the rev range that the motor is seeing most of which for almost all forms of racing is the upper half of the powerband ie where power is always higher than torque.
Horsepower+gearing>>>>>>torque as far as a number goes.
Think what would happen if only a cars torque figures were used as a rating for advertising....
 

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Oh really? When an F1 engineer designs an engine what do you think he strives for, having the most power or the most torque?
A Miata has almost as much torque as an S2000, infact it has a better torque/weight ratio.. why then is it much much slower in a straight line?
Torque wins races sure.... torque in the rev range that the motor is seeing most of which for almost all forms of racing is the upper half of the powerband ie where power is always higher than torque.
Horsepower+gearing>>>>>>torque as far as a number goes.
Think what would happen if only a cars torque figures were used as a rating for advertising....
And then you look at the R10 lemans car and your whole theory gets thrown out the window. Im just saying that I would rather have a car with 650hp/650torque than a car with 750hp/550torque. But that is just me.
And F-1 car/motors can't produce torque because of the rules/regulations on the motor. Its got a like a 1 inch stroke because its a 2.4 litre naturally-aspirated V-8. Its not possible to make torque with that little of a stroke.
 

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Torque wins races, Horsepower wins shows

'nuff said
Tell that to team Titan. In a tire limited class like the extreme 10.5 class in ADRL you will reach a point were there is such a thing as to much TQ. Titan has been whipping 600+ inch blown injected V8s all year with about 200 inches from a 6cyl. Hell I think they finished the year with the record in the class. If you watch them race they are killing the V8s out of the hole because they have the right amount of TQ for that size tire. Bring a Turbo v8 street car and run it in a turbo street FWD class on a 24.5x9" tire and see if you still feel the same way. Bigger isnt alway better in racing.
 

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Depends on the transmission and tire size. A stock K20A motor/tranny will pull harder than a K20A2 motor/tranny in the same chassis with the same tires. The K20A transaxle has a higher final drive.
On a motor dyno the K20A and K20A2 are very close. So is the K20Z1.
The K24 will make peak torque sooner, but it is fundamentally different. The longer stroke will ingest more air per RPM by design. Keeping it spinning safely is the key :up:
that's why I am going with the K20A complete swap tuned by Kpro.
 

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I think k20a's are a waste of money. you can buy a k20a2,z1,z3 swap for 3gs. you can add a freakin lsd,rbc,cams,a red valve cover lol and make more power than a k20a, and it would still cost less. if you get z3, shit you could build your whole motor up with the extra money. cause it already has the rbc,lsd,4.7.
 

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Discussion Starter #15
You listed a variance in yer first post of 30 ft.lbs. Yup I took into consideration you knew the difference between torq and ponies before posting. You'll feel a BIG difference in torq gains, especially in a game where one spends $$$$ for a few horsepower. You'll feel torq gains in any gear selected. You'll feel HP gains when at the end of each gears practical range.
i apologize for not being more clear in my statements and questions. i will try again.
so you have a u.s. spec k20z1 with 201 hp and 143 ft/lb oftorque and a k20a-r from japan with 217 hp and 152 ft/lb of torque. now we all would expect that the k20a-r would pull harder and climb rpm's faster then the k20z1 ultimately being the faster engine. for the time being i'm excluding all other factors of torque multiplication and reduction(i.e. tire size, final drive, transmission gear ratios, etc.)i am focusing purely on these two engines, imaging that they are in identical vehicles.

realisticly how much of a difference is that 9 ft/lb of torque going to make? Is k20a-r car going to feel a much harder pull or just a slight difference in comparison to k20z1 car?

i know i have not mentioned or keyed in on anything to do with the horsepower numbers. please be patient. I want to work out this part first and then we'll throw in the equation of different horsepower figures but for the time being can we assume these cars have the same horsepower as well.

What i meant when i was talking about not noticing the difference in first or second gear was that when in those two gears torque multiplication is already so great that the addition of more torque might not be as noticeable(assuming full tire grip) when compared to a third gear pull where multiplication of torque is far less therefore that 9 ft/lb of torque may put a substantial gap between the two cars in a race. What do you think? or am i out to lunch?
 

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The higher torque motor at X RPM will accelerate faster. It will cover the ramp range, a span of RPM, in a quicker time giving identical conditions. It will be faster. Now the question is how much does that HP cost. Find your goal, and from there you can build a combo that will yield the best $$$/HP ratio.
 

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Discussion Starter #17
okay so back to the original question. Just how much of a difference are you actually going to notice between these two engines in identical cars?

Is it safe to assume that a k20z1 and a k20a-r have simular looking power and torque curves?
 

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Oh really? When an F1 engineer designs an engine what do you think he strives for, having the most power or the most torque?
A Miata has almost as much torque as an S2000, infact it has a better torque/weight ratio.. why then is it much much slower in a straight line?
Torque wins races sure.... torque in the rev range that the motor is seeing most of which for almost all forms of racing is the upper half of the powerband ie where power is always higher than torque.
Horsepower+gearing>>>>>>torque as far as a number goes.
Think what would happen if only a cars torque figures were used as a rating for advertising....
Keep in mind that hp = tq * rpm / 5252.

So hp alone doesn't mean much. You only have hp because you have tq.

So tq + proper gearing is what makes the difference. With vtec, vtc, etc. Honda has done a lot to broaden the engines powerband and smooth out the torque curve. Add a good tranny on top of that that keeps you in that powerband after shifting and you have a good combination.
 

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I think k20a's are a waste of money. you can buy a k20a2,z1,z3 swap for 3gs. you can add a freakin lsd,rbc,cams,a red valve cover lol and make more power than a k20a, and it would still cost less. if you get z3, shit you could build your whole motor up with the extra money. cause it already has the rbc,lsd,4.7.
Agreed. k20a makes sense if someone has to build according to rules.
 
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