Just wondering if anybody has played around with this on here. I'm going to give it a shot on my b16 in the future until then it's just my turbo. I know there are some drawbacks to twincharging, but there is also no boost lag!

If anyone has done it post your setup. And dyno numbers if possible.

my possible setup on e85
1000cc injectors
hondata (with a good tune)
jrsc on 6psi or so
60 trim on another 6-10 psi
walbro 255
full 3" exhaust
3 bar map sensor

block will be built

 

no one has messed with twincharging? how about stock block low boost twincharging? or any comments regarding not doing it or go for it?

 

reason its just plain senseless in my opinion on a honda.... why twin charge when a single turbo can make crazy power? unless you are a show car and want a shock effect on ricers... its like when some local ask me how much power I am building my current setup for and I tell them 800whp they ask if its twin turbo.

 

Ive yet to see a twin charged setup make a better power band than a properly sized turbo.

 

https://honda-tech.com/forums/welding-fabrication-53/twin-charged-civic-2755640/ Not a show car for sure.

 

Type D16z6/y8 Twincharge and you will find mine on two other forums

 

There are so many of them out there...

Twincharging always offer a broader powerband. You just can't find a turbo-only Honda cranking out 170-180 lbft of torque from 2000-5000+ when the turbo spools up. Twincharging increases VE and makes the motor behave like a much bigger one. By comparison, if you had a 1.8L spooling a GT35R, twincharging would be similar to a 2.8L spooling the same turbo = better powerband...

 

yeah i completely disagree about the "ricer" show off effect. Ive seen a few twincharged cars and i know that the top end can get chocked if your supercharger can flow enough, but with both on moderately low boost it should be an amazing torque curve with at LEAST decent results!

 

theirs a prelude ive seen before with a twin charge setup he has pics somewere on here i beleive

 

Ha...that's the first car that came to my mind when twincharging was mentioned

 

There's the old ClemsonHatch car as well (with whoever the heck the previous owner was...can't think of his name off the top of my head).

 

Its just not worth the money, a properly sized turbo will spool fast enough and give a great powerband and not ROB hp like a charger dows. and a charger isnt instant full boost still takes some rpm to reach that maximum boost. im nto saying alot of rpm but some and they take power away from driving them. Id rather run a straight t3 or even a t25 to get lowe end grunt and still pull a little up top like a charger would or just lose a few hunred rpm of low end for a little bit larger turbo. Frankly honda motors arent ment for torque, thats why there so damn rev happy

Even with a turbo on the car that doesnt spool early the turbo is still always working and the low wned of the engine will increase reguardless of spool. the throttle responce will increase and so will torque production. I'm not at all a fan of a supercharger when a turbo is just more effecient at makign power and when properly sized will far outform a charger hands down.

 

Twincharging is very complicated, and often there are tons of myths around it and people drawing early conclusions without fully understanding what is actually happening. Over the years, I have read magazine articles, people's builds, race cars, etc.. and they often abort the project and thinking the supercharger is somehow "restrictive", but in fact, they had no clue why it resulted that way.

Here's a quick post I made over on another forum (Supra forum), briefy describing the compound twincharging process, and how I managed to make MORE power with a twincharged setup versus a typical single turbo setup:

Posted by Tony the Tiger
Guys get greedy when running compounded twincharged setups. Especially those who try to run like 10+ PSI of boost from the blower, thus, creating a lot of unnecessary heat. With all that heat, the amount of boost created by the blower gives no power increase. The other problem is that it takes energy from the crankshaft to make boost from the SC, and due to turbo exhaust back pressure, each PSI of boost from the SC nets lesser overall power due to lower VE. The parasitic losses from the SC simply overcomes the power gain when you start to run more boost from the blower. More boost, more parastic losses, more heat as well. Thus, it always appear that the motor needs so much more boost to make the same power.

There are lots of tricks and know-how in order to make the setup work, and it depends on how you size the turbo and the turbine as well, and understanding what is actually happening in a twincharged setup, and knowing how to keep things efficient.

A 3.0L V6 or I6 (eg. 2JZ, or a typical 220HP NA 6-cyl) motor needs is very little boost to give the turbo a good kick. A regular 2JZ-GTE, basic cams and port work and a decent sized single turbo, makes about 150-160 lbft of torque before the turbo spools. A 2JZ-GTE without boost, is about the same as an NA 2JZ just for comparison's sake, but it will make less power due to the turbo holding it back (turbo needs to spool in order to increase VE). This initial torque before the turbo kicks in would determine the VE of the motor, thus, you will get a general idea how soon the turbo will pick up and spool up fully. VE, is how much air and fuel those cylinders are being filled at a certain RPM. Displacement is just a figure. A 5.0L V8 that has 40% VE, will not spool a turbo faster than a 3.0L 6-cyl at 85% VE.

About 4-5 PSI of boost from a MP62 SC on a 3.0L motor can already increase low RPM torque to about 200-220 lbft of torque @ wheels at the lower/mid RPM band, thus, it tranforms the motor to behave like a much bigger engine. At such low boost, air temps are very minimal. A common 4.0L V8 for example, like a 1UZ-FE, or even the E92 M3 V8 (which is a high output V8 in NA form) also makes about 200-220 lbft of torque @ wheels from 2000-4000RPM. A low boost SC pulley on a 3.0L motor can already match the torque output and "energy" as a 4.0L V8 as a basic comparison.

That means a 3.0L 6-cyl under 4-5 PSI of boost from the blower, behaves exactly like a 4.0L V8 no questions asked. That's what it exactly did to my Camry (3.0L V6). Without the blower, my 3.0L V6 was making full boost at 5200RPM with an HKS T51R KAI (71mm turbo, 1.00A/R). After the blower, it makes full spool at 3800-4200RPM, just like what a bigger motor would do. The car also gets a massive rush of torque, and easily hits 12-15 PSI of boost at 3000-3500RPM, similar to when I had a much smaller T04E turbo back in the days.

For a compound twincharged Toyota 3.0L setup, the turbo has to be sized for a 4.0L V8. That's the major thing that other people overlook. They still size the turbo for a 3.0L 6-cyl which is a big mistake. The turbine is going to choke to hell. The compressor will run on a totally different portion on the compressor maps and probably choke. Along with the unintercooled boost and heat from the supercharger for those who try to run high boost from the SC, it doubles the problem so guys end up running like 30 PSI of boost just to make the same power as 20 PSI of boost on turbo alone. All the boost provided from the SC had no power increase, so it appeared the SC is "restrictive". At this point, everyone thinks it is inefficient and abandons the setup...lol

With my Camry, I gained power from twincharging across the entire RPM band. Due to the difference in intake pressure vs exhaust pressure, it means that my intake valves are seeing 26 PSI of boost, but my turbo is only working at 20 PSI of boost. This creates a significant reduction in exhaust pressures. The drastic difference between intake and exhaust pressures allow me to run way more ignition timing, lower EGT's, make more power on pump gas, and will eventually allow much more overlap and bigger cams. This also makes my turbo run at a lower pressure ratio, but much higher flow. So you have to size the compressor that is very efficient at low boost and high air flow. It is the exact opposite of what a typical higher revving import engine wants (lower flow, high pressure ratios).

Understanding the theory behind it will make the setup work. My Camry made 562 WHP at 26 PSI on a 1MZ-FE V6, which is typical for this economy V6 engine. After the supercharger, I made 580 WHP at the same boost, but 1000RPM less to get full boost. The car feels like a V8 spooling a small turbo, versus dead lag and sluggishness without the SC.

It only works in compound twincharging. Bypassing the blower when the turbo begins to spool up will not maintain the same engine VE during spool up. It does not work in the same fashion, and only works by compounding it.

With that being said, the supercharger in compound fashion is acting like an "inline air pump". Same theory would apply, as if you had two fuel pumps plumbed in series. One pump works under lesser pressure, thus, increasing in flow; while the other continues to deliver maximum flow with pressure fed through the pump inlet. However, you can never outflow the biggest pump in the system (aka the turbo). So for a compound twincharged setup to work, the turbo must be sized accordingly. What guys do is size the turbo for "better spool", failing to realize that turbine requirements are totally different with an SC on there.

The supercharger is always "adding" whatever flow and pressure that it is being fed. If you run 20 PSI at the turbocharger, then the supercharger only adds a certain amount of boost on top of that. If the SC had a 6 PSI pulley, your total boost is 26 PSI. If you run 30 PSI from the turbo, your overall boost at the engine is 36 PSI. Quite frankly, it is the same principle as compound turbocharging, but the first air pump (aka SC) gets boost under instantly.

The only reason why I gave up the twincharging setup on my Integra is due to the JRSC's poor belt drive system. I had the setup running well and matching the same power I had on turbo alone (650 WHP @ 24 PSI on pump) and managed to spool up my 71mm turbo at 4500RPM, but because I spin the motor up to 9700-10000 RPM, the SC and alternator belt just kept disintegrating after a day or so... sigh.

 

End of discussion :p

 

Thanks tony the tiger that was a great post but i already knew about that! Really it's common sense if you are trying to push more air through the turbo exhaust housing, it needs to be bigger...The same principle applies to trying to turbocharge with stock exhaust. It's just going to choke the hell out of it.

 

No, you made a mistake...

Turbine flow and requirement is determined by airflow and BSFC... From there, you can determine how much airflow was used to make a certain HP and TQ, and how much fuel was used, thus, be able to determine how much exhaust energy is being pushed out the exhaust ports. With the SC on there, the motor behaves like a bigger motor. Due to the reasons I've explained above, the relationship between SC boost vs turbo boost and the difference in efficiency is what ultimately requires a different sized turbine.

It's not due to pushing "more air into the engine".. The overall airflow is similar, but the difference is due to less efficient form of power and torque; just like why turbine requirements are different when compared to an H22A turbo vs a B16A turbo. Both motors could be running 500 WHP for example, but the H22A will need more turbine flow because of higher BSFC.

Twincharged or not, if your goal was to make 550 WHP, you would choose a GT3582R, correct? But without twincharged on a B18C for example, an ideal turbine would be a 0.63 a/r housing on turbo boost alone and still have acceptable TIP @ 550 WHP. With twincharged, you should be choosing the 1.06 A/R housing instead with the same 3582R compressor. Depending on how much power and torque the SC boost develops, you may want an even bigger turbine.

 

ok i see what your saying which is what i thought i meant, but now that you put it like that i see it differently. Correct me if im wrong...your saying since the s/c makes the engine perform like a bigger displacement engine, when you twincharge you have to size the housing and flow of the turbo to match the "larger engine" correct?

 

Sizing a turbo for a larger engine is based on the exhaust flow of the given motor. Compressor is sized based on airflow and horsepower production.

So if your goal was to make 600 WHP on a 3.5L 350Z for example, the exhaust turbine requirement is totally different than say making 600 WHP on a B16A motor. The 350Z will need more exhaust flow from the turbine wheel just because it makes more torque, less efficiency (much higher BSFC), lower RPM, lesser VE per engine displacement, lower compression ratio and so forth. For the same given fuel, the B16A is higher compression, and uses less fuel for the same 600 WHP. Less fuel, less wasted energy, etc.. would mean lesser exhaust energy and lesser exhaust flow. This is a very basic way to put this

However, since both cars are planning to make 600 WHP, the compressor will be sized with roughly the same flow requirements (give or take a few lbs/min and different efficiency ranges). This would be a 62mm billet compressor wheel let's say... But you don't go larger on the compressor because there is no point of doing so unless you plan to make 600+ WHP more.

So real life comparison for 600 WHP on both motors would be (example):

350Z = PTE 6265 T4 housing (A/R is for finer sizing)
B16A = PTE 6262 T3 housing

 

One thing to consider when twinchargeing with a turbo and (roots) supercharger is that traditionally roots superchargers are integrated into the intake manifold. And due to practice of low boost they generally have little to no intercooling.

But if you want to compound you need to consider the compounded heat, so for that application you would want to divorce the supercharger from the intake manifold so that you can redirect into an intercooler.

Something like this:
filter -> turbo -> intercooler -> supercharger -> intercooler -> manifold

http://www.youtube.com/watch?v=VOk-HsydQfc

http://www.youtube.com/watch?v=sGHOYZ8r_oI

 

That lotus is amazing. I wanted to run the turbo->intercooler->s/c->water to air intercooler already. And tony i already understand that, you need to size the compressor for the hp goals...although i honestly don"t have a hp goal in mind because this particular build for me is not about the hp in the end its about a car that has an amazing acceleration. If i wanted to say a goal i would say between 400-450! Thanks for all the input.

 

The LHT intercooler works with the JRSC without having to move it from its intake manifold position, FYI. Very functional, if a little pricey (though I doubt pricier than the fab work required for moving the charger).