Legitimate questions about b18 JRSC
04-18-2004, 08:41 AM
#1
Honda-Tech Member
Thread Starter
Join Date: Jul 2003
Location: The Zoo,, MI, USA
Posts: 3,180
Likes: 0
Received 0 Likes
on
0 Posts
Legitimate questions about b18 JRSC
I have some questions about b18 jrsc setups. I have searched, but myr euslts have either but inconclusive or nonexistent on these issues. That, or I just want some confirmation
1. I read that you can use a b18c setup on a b18b by simply boring out new holes in the mani to match the studs on the head. Is this true? Would it be worthwhile? It seems to me that it would make more power being a bigger blower, and that with proper fuel management this would be safe power.
2. I know that with turbo setups, you usually say your engine is 'safe to xxxwhp' etc. However becuase of the draw on the engine by a super charger, are the numbers different,e ven with proper tuning? For example, I am confident with a hondata and larger injectors on a good tune I could make 250whp reliabily on a b18b, however I do not know if the same would be true for a super charged b18b (although I know I will not reach 250whp on a jrsc)
3. How do the qrt mile times compare generally, at equal hp? In other words, becuase super chargers make more power low end, would a 200whp super charged integ beat a 200whp turboed integ?
4. I read about the lht intercooler, bt is there any other way to do it? What if, perhaps I used a radiator ont he front and ran it via hoses and a pump in a loop to a block which I placed between the blower and the mani, having it bored and sealed to match the port on the sc. In other words, between the blowe and the mani Id have a box with a hole in it thru which coolant was running. I could have an empty block cnc'ed and welded by a local machine shop, so is this possible? I dont know how the jrsc bolts up.
5. At 10psi (crv crank pully and jrsc 8lb pully) does the heat of the sc itself have any kind of affect on the intake charge temp, or is it still 99% compression process.
6. Can someone PLEASE hook me up with some vids/times/numbers of super charged LS's? All of the ones I found were dead.
I will use this info in my decision of JRSC/Kamakazi header/Hondata/440CC/2.5in Exhaust/Turbo cam OR hondata tuned turbo setup built around an 18g/small t3 snail for fast spooling. This is a daily driver that I put quite a few miles on, and I dont want something I will speed TOO much in either. Thats the draw of an SC to me, I wont have to go thru 2 - 3 gears to really show the power of my engine (spool time) itll be there all of the time. I guess if the turbo spooled by 3gs that wouldnt be too bad, but.... idk I am a confused person on this issue ;P
1. I read that you can use a b18c setup on a b18b by simply boring out new holes in the mani to match the studs on the head. Is this true? Would it be worthwhile? It seems to me that it would make more power being a bigger blower, and that with proper fuel management this would be safe power.
2. I know that with turbo setups, you usually say your engine is 'safe to xxxwhp' etc. However becuase of the draw on the engine by a super charger, are the numbers different,e ven with proper tuning? For example, I am confident with a hondata and larger injectors on a good tune I could make 250whp reliabily on a b18b, however I do not know if the same would be true for a super charged b18b (although I know I will not reach 250whp on a jrsc)
3. How do the qrt mile times compare generally, at equal hp? In other words, becuase super chargers make more power low end, would a 200whp super charged integ beat a 200whp turboed integ?
4. I read about the lht intercooler, bt is there any other way to do it? What if, perhaps I used a radiator ont he front and ran it via hoses and a pump in a loop to a block which I placed between the blower and the mani, having it bored and sealed to match the port on the sc. In other words, between the blowe and the mani Id have a box with a hole in it thru which coolant was running. I could have an empty block cnc'ed and welded by a local machine shop, so is this possible? I dont know how the jrsc bolts up.
5. At 10psi (crv crank pully and jrsc 8lb pully) does the heat of the sc itself have any kind of affect on the intake charge temp, or is it still 99% compression process.
6. Can someone PLEASE hook me up with some vids/times/numbers of super charged LS's? All of the ones I found were dead.
I will use this info in my decision of JRSC/Kamakazi header/Hondata/440CC/2.5in Exhaust/Turbo cam OR hondata tuned turbo setup built around an 18g/small t3 snail for fast spooling. This is a daily driver that I put quite a few miles on, and I dont want something I will speed TOO much in either. Thats the draw of an SC to me, I wont have to go thru 2 - 3 gears to really show the power of my engine (spool time) itll be there all of the time. I guess if the turbo spooled by 3gs that wouldnt be too bad, but.... idk I am a confused person on this issue ;P
04-19-2004, 07:19 AM
#3
Join Date: Jan 2003
Location: Manchester, NH, USA
Posts: 1,273
Likes: 0
Received 0 Likes
on
0 Posts
Re: Legitimate questions about b18 JRSC (Atheist)
I hate superchargers, so I can't answer all of these questions. I will do my best though.
That's a very legitimate question. Think about it this way:
If a turbo car is good to 250 whp, that means it can take XXX crank horsepower, with the diference due to drive losses. The limit for that car is really not 250 whp, but the crank horsepower that corresponds to 250 whp on that turbo car.
So, if the crank horsepower limit is the same for your supercharged car, the wheel horsepower limit will be lower (maybe about 20 hp lower). That's because your losses from the cylinder to the wheels are greater, due to the drag of the supercharger.
However, there is something else very important at hand here. 300 crank horsepower at 7500 rpm (a turbo car's peak power, for example) is NOT the same in terms of engine loading as 300 crank horsepower at 5000 rpm (lower peak power rpm with a roots type supercarger). At lower rpm's, the combustion actually lods the motor up more than at higher engine speeds.
Because of this, you will likely have lower power limits than a turbo car.
Also, consider the additional fact that a roots blower will put out a charge temp that is quite a bit hotter than a turbo at the same boost level, and you have a car that is more suspectible to detonation. As detonation is the main killed of forced induction Honda motors, you also have a limitation due to that.
You probably can begin to see why I don't like superchargers.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">3. How do the qrt mile times compare generally, at equal hp? In other words, becuase super chargers make more power low end, would a 200whp super charged integ beat a 200whp turboed integ?</TD></TR></TABLE>
It's all about power under the curve, for two equal cars. If you both have the same power curve but the turbo car has it 2000 rpm later, you will still end up in the same place.
Turbo cars tend to have more power under the curve in the region you use when racing. That's why they have a tendency to be faster on the drag strip.
Roots blown cars have more power under the curve in the daily driving / lugging / cruising range of engine speeds, which is why they "feel" faster on the street. However, once you downshift and put your foot in it, the turbo car has the upper hand.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">4. I read about the lht intercooler, bt is there any other way to do it? What if, perhaps I used a radiator ont he front and ran it via hoses and a pump in a loop to a block which I placed between the blower and the mani, having it bored and sealed to match the port on the sc. In other words, between the blowe and the mani Id have a box with a hole in it thru which coolant was running. I could have an empty block cnc'ed and welded by a local machine shop, so is this possible? I dont know how the jrsc bolts up.</TD></TR></TABLE>
I won't start a whole thread on heat exchangers. However, note this one thing: You can't just put air through a hole surrounded by cold metal and hope to cool it down. You need the smaller passages and large surface area of fins, like a FMIC or a radiator has.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">5. At 10psi (crv crank pully and jrsc 8lb pully) does the heat of the sc itself have any kind of affect on the intake charge temp, or is it still 99% compression process.</TD></TR></TABLE>
The charge heating comes from a lot of places. The inefficiency of the blower, the heat of the motor working its way into the blower, and the heat of friction within the blower.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">I will use this info in my decision of JRSC/Kamakazi header/Hondata/440CC/2.5in Exhaust/Turbo cam OR hondata tuned turbo setup built around an 18g/small t3 snail for fast spooling. This is a daily driver that I put quite a few miles on, and I dont want something I will speed TOO much in either. Thats the draw of an SC to me, I wont have to go thru 2 - 3 gears to really show the power of my engine (spool time) itll be there all of the time. I guess if the turbo spooled by 3gs that wouldnt be too bad, but.... idk I am a confused person on this issue ;P</TD></TR></TABLE>
In my opinion, there is no reason not to go turbo. A supercharger will give you more power where you don't really need it, and the turbo will give you more power where you do.
Small displacement imports are generally not very torquey; however, do you really need or want power at 2500 rpm in a FWD daily driver? I know I would not. All that will result in is more wheelspin and worse gas mileage.
Since this is your thread, I will let you decide where it goes. If you want to talk about the benefits of turbos vs. superchargers, let me know!
Originally Posted by Atheist
2. I know that with turbo setups, you usually say your engine is 'safe to xxxwhp' etc. However becuase of the draw on the engine by a super charger, are the numbers different,e ven with proper tuning? For example, I am confident with a hondata and larger injectors on a good tune I could make 250whp reliabily on a b18b, however I do not know if the same would be true for a super charged b18b (although I know I will not reach 250whp on a jrsc)
If a turbo car is good to 250 whp, that means it can take XXX crank horsepower, with the diference due to drive losses. The limit for that car is really not 250 whp, but the crank horsepower that corresponds to 250 whp on that turbo car.
So, if the crank horsepower limit is the same for your supercharged car, the wheel horsepower limit will be lower (maybe about 20 hp lower). That's because your losses from the cylinder to the wheels are greater, due to the drag of the supercharger.
However, there is something else very important at hand here. 300 crank horsepower at 7500 rpm (a turbo car's peak power, for example) is NOT the same in terms of engine loading as 300 crank horsepower at 5000 rpm (lower peak power rpm with a roots type supercarger). At lower rpm's, the combustion actually lods the motor up more than at higher engine speeds.
Because of this, you will likely have lower power limits than a turbo car.
Also, consider the additional fact that a roots blower will put out a charge temp that is quite a bit hotter than a turbo at the same boost level, and you have a car that is more suspectible to detonation. As detonation is the main killed of forced induction Honda motors, you also have a limitation due to that.
You probably can begin to see why I don't like superchargers.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">3. How do the qrt mile times compare generally, at equal hp? In other words, becuase super chargers make more power low end, would a 200whp super charged integ beat a 200whp turboed integ?</TD></TR></TABLE>
It's all about power under the curve, for two equal cars. If you both have the same power curve but the turbo car has it 2000 rpm later, you will still end up in the same place.
Turbo cars tend to have more power under the curve in the region you use when racing. That's why they have a tendency to be faster on the drag strip.
Roots blown cars have more power under the curve in the daily driving / lugging / cruising range of engine speeds, which is why they "feel" faster on the street. However, once you downshift and put your foot in it, the turbo car has the upper hand.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">4. I read about the lht intercooler, bt is there any other way to do it? What if, perhaps I used a radiator ont he front and ran it via hoses and a pump in a loop to a block which I placed between the blower and the mani, having it bored and sealed to match the port on the sc. In other words, between the blowe and the mani Id have a box with a hole in it thru which coolant was running. I could have an empty block cnc'ed and welded by a local machine shop, so is this possible? I dont know how the jrsc bolts up.</TD></TR></TABLE>
I won't start a whole thread on heat exchangers. However, note this one thing: You can't just put air through a hole surrounded by cold metal and hope to cool it down. You need the smaller passages and large surface area of fins, like a FMIC or a radiator has.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">5. At 10psi (crv crank pully and jrsc 8lb pully) does the heat of the sc itself have any kind of affect on the intake charge temp, or is it still 99% compression process.</TD></TR></TABLE>
The charge heating comes from a lot of places. The inefficiency of the blower, the heat of the motor working its way into the blower, and the heat of friction within the blower.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">I will use this info in my decision of JRSC/Kamakazi header/Hondata/440CC/2.5in Exhaust/Turbo cam OR hondata tuned turbo setup built around an 18g/small t3 snail for fast spooling. This is a daily driver that I put quite a few miles on, and I dont want something I will speed TOO much in either. Thats the draw of an SC to me, I wont have to go thru 2 - 3 gears to really show the power of my engine (spool time) itll be there all of the time. I guess if the turbo spooled by 3gs that wouldnt be too bad, but.... idk I am a confused person on this issue ;P</TD></TR></TABLE>
In my opinion, there is no reason not to go turbo. A supercharger will give you more power where you don't really need it, and the turbo will give you more power where you do.
Small displacement imports are generally not very torquey; however, do you really need or want power at 2500 rpm in a FWD daily driver? I know I would not. All that will result in is more wheelspin and worse gas mileage.
Since this is your thread, I will let you decide where it goes. If you want to talk about the benefits of turbos vs. superchargers, let me know!
04-19-2004, 01:01 PM
#4
Honda-Tech Member
Thread Starter
Join Date: Jul 2003
Location: The Zoo,, MI, USA
Posts: 3,180
Likes: 0
Received 0 Likes
on
0 Posts
Thank you for your replies, Kyle. It gave me a lot to think about. The more I think about it, the more I think id be best off with a smaller t3 or even an 18g snail thatd spool up around 3500, whoichw ould be nice for 'spirited' daily driving becuase of when it spools. Its mainly just a lack of desire to have to really be flying, to feel the power of the setup you know? I feel like with an sc, and the power being more immediate, I wouldnt have to downshift and stay in the gear for too long. Ill probably end up with an ls due to funds, too, so even though the gears are longer a 6700 (or is it 6800? ) that still isnt much time in boost.
) that still isnt much time in boost.
Thread
Thread Starter
Forum
Replies
Last Post
