n/a BETA max hp #'s
#21
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just a note: honda was building high revving engines way before the s2000, so they already had the technology. integra type-r was the first 9k i believe and the integra gs-r is either 7500 or 8k.
just letting you know it's nothing new for honda tongue.gif
just letting you know it's nothing new for honda tongue.gif
#22
<div class='quotetop'>QUOTE </div><div class='quotemain'>Red:
Denis,
What you're thinking of is *rod/stroke* ratio, a one of the main engine geometry factors that dictates how well it will rev. You take the length of the rod, divided by the full stroke of the crank. The higher this value, the more rev-happy it will be.
The *perfect* R/S is said to be right around 1.75:1... The Honda B16A2 (US Civic Si and CDN Civic SiR) has an R/S of 1.74:1; the Honda B18C5 found in the Integra Type R has an R/S of 1.72:1.
The Mitsubishi 4G63 has an R/S of around 1.65:1, which is enough to get it winding to around 7800-8000 reliably after modification.
The Hyundai BETA 2.0L has an R/S of around 1.54:1. The general feeling here is somewhere between and sad.gif
Long stroke, short rods, sucks for revving. What's funny tho is, the 1.8L BETA actually is around 1.7:1 with it's shorter stroke and longer rods in the 2.0L block. Theoretically, it should be able to wind into the 8K range without much drama. I don't have the first clue if anyone's tried that yet...</div>I was just curious what the ratio would be for the 2.7L V6?
Stroke I found at 2.95
Bore (probally not helpful) 3.41
Running at a lower compression of 10.0 then the 2.0L I4.
I thought I would give the 2.7L a try to see whats the most I can get out of it N/A cause I guess the whole F/I thing is out of the question. KORE is coming out with a lot of goodies, and no doubt Sharkracing may have some nice things to add on too!
Denis,
What you're thinking of is *rod/stroke* ratio, a one of the main engine geometry factors that dictates how well it will rev. You take the length of the rod, divided by the full stroke of the crank. The higher this value, the more rev-happy it will be.
The *perfect* R/S is said to be right around 1.75:1... The Honda B16A2 (US Civic Si and CDN Civic SiR) has an R/S of 1.74:1; the Honda B18C5 found in the Integra Type R has an R/S of 1.72:1.
The Mitsubishi 4G63 has an R/S of around 1.65:1, which is enough to get it winding to around 7800-8000 reliably after modification.
The Hyundai BETA 2.0L has an R/S of around 1.54:1. The general feeling here is somewhere between and sad.gif
Long stroke, short rods, sucks for revving. What's funny tho is, the 1.8L BETA actually is around 1.7:1 with it's shorter stroke and longer rods in the 2.0L block. Theoretically, it should be able to wind into the 8K range without much drama. I don't have the first clue if anyone's tried that yet...</div>I was just curious what the ratio would be for the 2.7L V6?
Stroke I found at 2.95
Bore (probally not helpful) 3.41
Running at a lower compression of 10.0 then the 2.0L I4.
I thought I would give the 2.7L a try to see whats the most I can get out of it N/A cause I guess the whole F/I thing is out of the question. KORE is coming out with a lot of goodies, and no doubt Sharkracing may have some nice things to add on too!
#23
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Rudy-
You've got a point there. The S2000 Motor is basically a Motorcycle motor, just a really damn big one. Honda's been building inline-4 motorcycles that rev to 14,000 for quite a while, the difference of course is displacement. The 954RR has a 75mm bore, but an utra short 54mm stroke. Even at 10,000 RPM these pistions only have to travel 540 meters per minute. 21 meters Less than the beta at 6000 RPM.
The Rod ratio has to do with the pistion acceleration, the side loading of the pistion against the bore and frictional losses against the cylinder walls. The shorter the rod ratio, the greater the acceleration loads on the pistion, and the greater the side loading against the cylinder walls, and the greater friction (lost power).
You've got a point there. The S2000 Motor is basically a Motorcycle motor, just a really damn big one. Honda's been building inline-4 motorcycles that rev to 14,000 for quite a while, the difference of course is displacement. The 954RR has a 75mm bore, but an utra short 54mm stroke. Even at 10,000 RPM these pistions only have to travel 540 meters per minute. 21 meters Less than the beta at 6000 RPM.
The Rod ratio has to do with the pistion acceleration, the side loading of the pistion against the bore and frictional losses against the cylinder walls. The shorter the rod ratio, the greater the acceleration loads on the pistion, and the greater the side loading against the cylinder walls, and the greater friction (lost power).
#24
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From what i saw and read about it two identical engines with only a rod lenght and piston change
(to accomodate the longuer rod)will tend to make a bit more power and higher rpm's
the only real benefits for us in this case would be the improved side loads
on a side note,v-8 wich are often tagged to be low rev engines can scream too...
take a 302 chevy engine (3* stroke 4* bore),put 6* rods in it (2:1 rod/stroke ratio)huge cam and great heads and it will turn up to 10000rpm's on a good run
Denis
(to accomodate the longuer rod)will tend to make a bit more power and higher rpm's
the only real benefits for us in this case would be the improved side loads
on a side note,v-8 wich are often tagged to be low rev engines can scream too...
take a 302 chevy engine (3* stroke 4* bore),put 6* rods in it (2:1 rod/stroke ratio)huge cam and great heads and it will turn up to 10000rpm's on a good run
Denis
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the key is the 3* stroke. That is ungodly short for a chevy 302. They shortened the stroke and lengthened the rod. The shorter stroke is what allows the high RPM.
The longer rod (6* is a DAMN LONG rod.) allows less side loads of the pistions/rings, and thus less friction at high RPM, and it will continue to make power at high RPM.
The longer rod (6* is a DAMN LONG rod.) allows less side loads of the pistions/rings, and thus less friction at high RPM, and it will continue to make power at high RPM.
#26
<div class='quotetop'>QUOTE </div><div class='quotemain'>Mike Free:
I'd say piston speed are at the danger level at, say, 8500 on the honda (but tech allows topping that), 7500 on the beta, and 6000 on a Chrysler 2.5. Just guessing there, but I'm probably close.
Rod ratio plays into this too, but I don't know the specs on these motors. Rod ratios affect the acceleration curve of the piston and the side loading in the bore.</div>For the 2.5 Chrysler, the danger level is almost 7,000 cause I get my mom's Cirrus flying up to about 6500 before it force-shifts me. And boy, does that Cirrus move. I can so easily wipe out 6-cylinder mustangs with it. It's funny when I beat them and yell out my window, *Nice mustang. Don'tchya feel bad that you got smoked by a FAMILY CAR??*
I'd say piston speed are at the danger level at, say, 8500 on the honda (but tech allows topping that), 7500 on the beta, and 6000 on a Chrysler 2.5. Just guessing there, but I'm probably close.
Rod ratio plays into this too, but I don't know the specs on these motors. Rod ratios affect the acceleration curve of the piston and the side loading in the bore.</div>For the 2.5 Chrysler, the danger level is almost 7,000 cause I get my mom's Cirrus flying up to about 6500 before it force-shifts me. And boy, does that Cirrus move. I can so easily wipe out 6-cylinder mustangs with it. It's funny when I beat them and yell out my window, *Nice mustang. Don'tchya feel bad that you got smoked by a FAMILY CAR??*
#27
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Nice! Those Mustang drivers must get REALLY pissed off at that....
About the 2.2/2.5 thing, I think Mike was referring to the old Omni/Horizon four-bangers, not the newer 6 cyl engine.
About the 2.2/2.5 thing, I think Mike was referring to the old Omni/Horizon four-bangers, not the newer 6 cyl engine.
#29
For those people that have all the mods, and are N/A pushing 140-160hp...how quick are you? anyone know what are you doing 0-60, or 1/4 mile? Has anyone broken 14sec 1/4mi? Or 0-60 in under 7 sec?
#30
I consistenly hit the 6.9-7.0 mark on the 0-60... I am not a 1/4 mile guy, With my tires, gearing and mod's I wanted the best 0-60 I could get. However the last run I did was a 15.2...
-Steve
-Steve