Newbie: Why do rotaries make such high HP on low boost?
#1
Junior Member
Thread Starter
Join Date: Sep 2002
Location: Raleigh, NC
Posts: 46
Likes: 0
Received 0 Likes
on
0 Posts
Newbie: Why do rotaries make such high HP on low boost?
Hi,
I'm writing using my brothers account and had a quick question(s):
How do rotaries run such huge horsepower numbers on lower boost levels? (I'm coming from an EJ20 background so forgive me)
Also, the single upgrade turbo kits seem to use huge turbos (72s, 78s etc) Putting one of those on my car would be insane lag. What are the lag characteristics of these single turbo kits?
Is it that the rotary engines produce an unusually high exhaust velocity as compared to inlines and boxers, thereby alowing the use of larger turbos?
Thanks
I'm writing using my brothers account and had a quick question(s):
How do rotaries run such huge horsepower numbers on lower boost levels? (I'm coming from an EJ20 background so forgive me)
Also, the single upgrade turbo kits seem to use huge turbos (72s, 78s etc) Putting one of those on my car would be insane lag. What are the lag characteristics of these single turbo kits?
Is it that the rotary engines produce an unusually high exhaust velocity as compared to inlines and boxers, thereby alowing the use of larger turbos?
Thanks
#2
Original Gangster/Rotary!
iTrader: (213)
Re: Newbie: Why do rotaries make such high HP on low boost?
Originally posted by protege5turbo
Is it that the rotary engines produce an unusually high exhaust velocity as compared to inlines and boxers, thereby alowing the use of larger turbos?
Thanks
Is it that the rotary engines produce an unusually high exhaust velocity as compared to inlines and boxers, thereby alowing the use of larger turbos?
Thanks
#4
Constant threat
The stock boost of about 11-12 lbs. maximum is not really all that high of boost levels.
For a street car that is decent, but look at Toyota's GTP cars of the '80s....they ran about 55 lbs of boost on a 1.5 litre engine to get over 700 hp, if memory serves....
For a street car that is decent, but look at Toyota's GTP cars of the '80s....they ran about 55 lbs of boost on a 1.5 litre engine to get over 700 hp, if memory serves....
#5
Full Member
Join Date: Aug 2002
Location: Scottsdale, AZ
Posts: 100
Likes: 0
Received 0 Likes
on
0 Posts
Rotary engines are completely different from pistons, as you already know. Therefore, numbers are going to be very different also. Take a look just at the size of the engine, 1.3l, and then take a look at a civic that is turboed, with their almight 1.8l if they don't swap it. Look at the number differences, its the way the engine was built and the workings of it that allows for the numbers to be high even with a lower boost.
#6
Junior Member
Join Date: May 2002
Location: wide awake
Posts: 44
Likes: 0
Received 0 Likes
on
0 Posts
i don't understand exactly what you mean about the civic comment. the largest engine they (honda) has put in a civic thus far was a 1.6L b16. but if you turbo'd a b18 like you were saying at teh same boost levels you would likely produce more hp than a 13b at teh same levels
1.8L@10lbs
http://hondata.com/dynoericksracinggm.html
1.8L@10lbs
http://hondata.com/dynogsrturbo.html
and just for ***** and giggles heres a 2.0@12.5lbs see 372hp
http://hondata.com/dyno372turboimportbuilders.html
turbocharged hondas ain't no joke man
1.8L@10lbs
http://hondata.com/dynoericksracinggm.html
1.8L@10lbs
http://hondata.com/dynogsrturbo.html
and just for ***** and giggles heres a 2.0@12.5lbs see 372hp
http://hondata.com/dyno372turboimportbuilders.html
turbocharged hondas ain't no joke man
#7
It's never fast enough...
Join Date: Feb 2001
Location: Miami - Given 1st place as the POOREST city in the US as per the federal government
Posts: 3,760
Likes: 0
Received 3 Likes
on
3 Posts
Yeah, but look at the extensive mods the engine has. With 11-12lbs, we have been known to push anywhere between 300-330 (or so) RWHP with only bolt on mods.
Let's use Adam Sawatari as a good example. The guy was running about 17lbs with a single, he dynoed somewhere around 550hp, and the guy ran mid 9s. To get anywhere near 550hp, a honda motor will have to at least run somewhere around 25psi or so.
Let's use Adam Sawatari as a good example. The guy was running about 17lbs with a single, he dynoed somewhere around 550hp, and the guy ran mid 9s. To get anywhere near 550hp, a honda motor will have to at least run somewhere around 25psi or so.
Trending Topics
#8
Originally posted by Flybye
Let's use Adam Sawatari as a good example. The guy was running about 17lbs with a single, he dynoed somewhere around 550hp, and the guy ran mid 9s.
Let's use Adam Sawatari as a good example. The guy was running about 17lbs with a single, he dynoed somewhere around 550hp, and the guy ran mid 9s.
#9
The main reason why a rotary makes so much hp is related to VE AND to a free path into the "combuston" chamber. Typically, 70% of intake restrictions on a piston engine are located in the head alone. We have no cylinder head, no valves, etc...It's a much straigher and less cluttered shot in AND out. Piston engines require higher boost levels to overcome those restrictions. This info comes from a head engineer at Ford, btw...
Michel
Michel
#10
It's never fast enough...
Join Date: Feb 2001
Location: Miami - Given 1st place as the POOREST city in the US as per the federal government
Posts: 3,760
Likes: 0
Received 3 Likes
on
3 Posts
Originally posted by Silver7
Where did you get this info? 550 sounds high for only 17 psi. I'm not saying he didn't do it but it would take a hell of a port job and a hell of a turbo to pull those kinds of numbers.
Where did you get this info? 550 sounds high for only 17 psi. I'm not saying he didn't do it but it would take a hell of a port job and a hell of a turbo to pull those kinds of numbers.
"Turbo Magazine" March 1999 P.82
Oh, I was a little bit off my figures
17.5lbs . He dynoed 548RWHP
The article states the 13b was extensively ported. No mention of the type of port job it is. "The main power adder is a one-off hybrid turbocharger from FasTrax Turbochargers.......the unit is a custom one off. A T4 turbine housing is joined by a diesel-based compressor housing that has been modified for rotary duty. A custom back plate is used to register the wheel which has been re-contoured for improved flow."
That's his secret sauce.
#12
fart on a friends head!!!
you guys are all wrong!!! the rotary engine creates so much power with such little boost because of its high amount of "mojo". it is a scientific fact that "mojo" has radical effects on many things. it makes ugly men attractive (austin powers). women usually cant bear the sight of a man with green "cavemanesque" teeth, but with the proper mixture of mojo into the bloodstream that same hygenically incorrect man can have the best of the best. its simply that simple. this equation can be related to the rotary engine and boost. lets say that the rotary engine is the ugly man with no chance in hell to succeed against the other more popular engines. . . oh my, here comes the boost. the boost is the rotary engines mojo. by adding this mojo directly into the bloodstream (bloodstream=fuel/air mixture) of the rotary engine he is now the hit on the street. . . now he is out on the road ready to eat everything up!!!. . . . . . . . . .. and maybe even get some head. . . . . . . . . .. . . . . . . . . .. piston head that is!!!
paul
paul
#13
Stabbed by a pen
iTrader: (1)
Originally posted by rotorbrain
you guys are all wrong!!! the rotary engine creates so much power with such little boost because of its high amount of "mojo". it is a scientific fact that "mojo" has radical effects on many things. it makes ugly men attractive (austin powers). women usually cant bear the sight of a man with green "cavemanesque" teeth, but with the proper mixture of mojo into the bloodstream that same hygenically incorrect man can have the best of the best. its simply that simple. this equation can be related to the rotary engine and boost. lets say that the rotary engine is the ugly man with no chance in hell to succeed against the other more popular engines. . . oh my, here comes the boost. the boost is the rotary engines mojo. by adding this mojo directly into the bloodstream (bloodstream=fuel/air mixture) of the rotary engine he is now the hit on the street. . . now he is out on the road ready to eat everything up!!!. . . . . . . . . .. and maybe even get some head. . . . . . . . . .. . . . . . . . . .. piston head that is!!!
paul
you guys are all wrong!!! the rotary engine creates so much power with such little boost because of its high amount of "mojo". it is a scientific fact that "mojo" has radical effects on many things. it makes ugly men attractive (austin powers). women usually cant bear the sight of a man with green "cavemanesque" teeth, but with the proper mixture of mojo into the bloodstream that same hygenically incorrect man can have the best of the best. its simply that simple. this equation can be related to the rotary engine and boost. lets say that the rotary engine is the ugly man with no chance in hell to succeed against the other more popular engines. . . oh my, here comes the boost. the boost is the rotary engines mojo. by adding this mojo directly into the bloodstream (bloodstream=fuel/air mixture) of the rotary engine he is now the hit on the street. . . now he is out on the road ready to eat everything up!!!. . . . . . . . . .. and maybe even get some head. . . . . . . . . .. . . . . . . . . .. piston head that is!!!
paul
#14
Junior Member
Join Date: May 2002
Location: wide awake
Posts: 44
Likes: 0
Received 0 Likes
on
0 Posts
the first engine was not extensively modified, it says in the write up that it was a sotck GSR engien and tranny. it also sates that it makes 260 hp at the wheels and 300 at the crank, all at only 10psi! and to top that it gets 30mpg on the highway. a stock FD only gets 255 at teh crank and something like 20mpg?
regardless i would still rather have a FD, im just saying that turbo'd honda's can creats some serious power. they are great engines.
regardless i would still rather have a FD, im just saying that turbo'd honda's can creats some serious power. they are great engines.
#15
You are forgetting one thing. What was the compression ratio on that first GSR engine? If it was a stock engine then I am sure its compression is higher then the stock FD engine's.
The FD has a 9:1 compression ratio. @ 10lbs of boost that is a simulated compression ratio of 15.1:1
If someone can find out the compression ratio of the GSR engine I can find out it's simulated compression ratio @10lbs of boost.
The FD has a 9:1 compression ratio. @ 10lbs of boost that is a simulated compression ratio of 15.1:1
If someone can find out the compression ratio of the GSR engine I can find out it's simulated compression ratio @10lbs of boost.
#16
Rotary Enthusiast
Join Date: Feb 2001
Location: Huntington Beach, CA, USA
Posts: 1,025
Likes: 0
Received 4 Likes
on
4 Posts
High exhaust gas energy and very straight exhaust ports (no valves in the way) allows us to use very big turbines so we can move more air (what the other guy said). Thats why we have big turbos on small engines and still don't have much lag. With big turbos you don't need as much boost to make power.
#17
Rotary Freak
iTrader: (1)
A few things about rotary engine propensity for boost.
1. Turbo is 4-6 inches away from exhaust;
2. Exhaust pulses are once every rotation of the crank even though the rotor runs at 1/3 the speed of the crank; and
3. The exhaust port is not a peripheral meaning it's a straight shot into the turbos.
1. Turbo is 4-6 inches away from exhaust;
2. Exhaust pulses are once every rotation of the crank even though the rotor runs at 1/3 the speed of the crank; and
3. The exhaust port is not a peripheral meaning it's a straight shot into the turbos.
#18
Rotary Enthusiast
the 1.3L rotary displ rating is based on 1 crank rev, the 4-cycle piston eng displ is based on 2 crank revs.
13B should be compared with a 2.6L piston eng, not 1.8L. that's what's done in road race competition regulations.
13B should be compared with a 2.6L piston eng, not 1.8L. that's what's done in road race competition regulations.
Thread
Thread Starter
Forum
Replies
Last Post