HKS Twincharge

[karma]

ok plain and simple, how does it work? does n e one know how the supercharger is "turned off" to allow the turbo to control boost in the higher RPMs? What is used for fuel needs? can this kit be custom fabricated? thanx

[DerekDorifto]

HKS made this kit for the 4AGZE back in the late 80's and into the early 90's. If you are familliar with the 4AGZE SC12 setup, it is controlled by a 12v signal from the ecu which electromagnetically engages/disengages the supercharger clutch assembly. The kit comes with a HKS Supercharger Controller, which modifies this SC12 signal to complement the boost made by the turbo. People have replicated it with standalone systems, but not too many have been 100% successful (it's difficult enough to tune the car with the original HKS kit alone). Try checking out Nad Parvez's UK site for his 4AGZE HKS TC setup.

[karma]

great wahts the address?

so the Hks kit doesn't use vacuum/boost to run any types of valves that close off the superchargers boost its competely controlled by placing them all on the same intake line and then using a signal to unlock the cluth on the supercharger right? thanx

[DerekDorifto]

http://www.nparvez.pwp.blueyonder.co.uk/twincharge.htm

btw: Nad sometimes posts here so maybe you can ask him directly

[fatredcircle]

For cosemetic purposes a tc is kool, but why would you want one for performance? aren't they a biatch to tune? And wouldn't you just use a ball bearing turbo instead? Because wasn't the TC supposed to take care of the lag associated with early turbochargers?
Just my two cents.

[bondobondo]

there was HUGE debate over this on the mods-list

the concensus is:

HKS came out with this over a decade ago, and turbo technology has come a LONG way over the last 10 yrs,

if HKS would do it again,

they would scrap the super charger.

[4Aaron GE]

Meh. I'd just use the kit to run a HUUUUUUUUUGE turbo.... :p

[DerekDorifto]

HKS did do it again Andrew, less than a year ago I remember seeing a Sport Compact Car or Super Street issue with a red DC2 Integra with a prototype HKS Twincharged Kit for the B18. Does anyone have that issue to scan and post?

[DerekDorifto]

http://www.teammeguiars.com/feat_typer.asp

[bondobondo]

i have seen a blitz twincharge with 2 turbos AND a supercharger for an RB26.

either taht or it may just be a blitz supercharger for the RB.

[ericlee303]

We are trying to figure out if we can cobble a twincharge kit together. Aaron thinks he knows how. I hope so - we have the standalone to do it.

[randedge]

Just out of curiousity, I plotted this dyno table's torque and horsepower figures into a graph.
(it's gerald san agustin's Twincharged MR2) 376 peak power...


And then re-plotted this graph of a relatively mild T3/T4 Turbocharged AE86 against the TWinCharged MR2's torque and hp lines...

http://sdsefi.com/features/aug03corolla.htm



The MR2 produces MORE torque and More HP ANYWHERE in the powerband.

Just for further proof, I even plotted a Cusco pulley'd SC.
(Mr. Lofthouse's MR2)



AE86 with relatively Big Turbo vs. stock-ish SC.

-The Cusco pulley equipped SC MR2 had no other mods but good ECU tuning with the Techtom, yet it produced MORE hp and More torque than the T3/T4 equipped Corolla at anything below 5000rpm.
-The largest difference in torque occurs at 3000rpm. (a 50lb/ft difference)

AE86 Turbo only VS. Gerald's Twincharged MR2.

-The powerband in the MR2 resembles that of a V8. No sudden dips and no sudden rises. From the bottom portion of the powerband up to the power peak, it took off very steeply and linearly.
-The T3/T4 equipped corolla by comparison had a less than even powerband. Below 5 grand, the slope isn't very steep, and above that, it just took off all of a sudden.

I also have researched twincharged systems a bit and for it to really work, 2 things are necessary: an SC switch-off at higher rpms, and a Bypass valve. I suppose you must add to that a really good standalone.

So just looking at one very good example such as Mr. San Agustin's (former?) MR2, with enough time, patience, and understanding of how to move switchovers around (when to open BPV and when to kill SC), a really nicely tuned twincharged setup will outdo any turbo system for a kickass powerband.

Even with Ball bearing turbos and more efficient compressors that can move spool time a few hundred rpms earlier, the low rpm tractability of a roots type blower will always win. I suppose you just have to find the sweet switchover spot.

Plot the points and see for yourself!