Twin charged ECU?

[Blazin674]

hey im in the process of putting a twin charged 4agze in my 1994 geo prizm and was wondering first off is it worth it to go with the twin charger setup? i will be running a heafty size turbo and dont want the turbo lag to interfere with my launches. i have heard that it is more of a "look what i can do" thing.i dont know if i should just upgrade the supercharger or just a turbo. also i was wondering if i should go with a greddy emanage ultimate or a power FC would be better for my app. does any one have any input on this subject ?

[REN69]

You're basically answering your own question dude.

As for aftermarket engine control.. depends how much you wanna spend, there's a few out there.

[punter]

Not much help on the ECU's as I'm not familiar with those units, but I was just wondering what you are using to switch between boost sources?? That seems to be a big stumbling block for twincharding. (unless your running the together, ie. cheating)

[REN69]

I believe that's the way the twincharger kit worked.. the SC worked all the time while the turbo kicked in at high rpm. (4500rpm I believe it was)

[punter]

Originally Posted by REN69

I believe that's the way the twincharger kit worked.. the SC worked all the time while the turbo kicked in at high rpm. (4500rpm I believe it was)

What kit is that?? Thats a crap way of doing it IMO. The HKS kit switched between them, charger down low and turbo up top.

This one runs parrelel



and this one sequential

[freakinbox]

this was covered in initial d with 2 rx7's lol. I swear that show has the answers to everything car related
- Ok big turbo is more laggy, but more powerful. Also they will be more smog legal. usually 1 larger turbo rather than 2 smaller ones
Twin turbo is more resonsive, but weaker than a single turbo. Will be harder to keep smog legal.

Super Charger is the most responsive since it's belt drivin. Not as much torque compared to a turbo and it will burn more fuel then if you turbo it. But it's the closest to the responsiveness of an N/A motor that a forced induction motor can get.

[punter]

Originally Posted by freakinbox

this was covered in initial d with 2 rx7's lol. I swear that show has the answers to everything car related
- Ok big turbo is more laggy, but more powerful. Also they will be more smog legal. usually 1 larger turbo rather than 2 smaller ones
Twin turbo is more resonsive, but weaker than a single turbo. Will be harder to keep smog legal.

Super Charger is the most responsive since it's belt drivin. Not as much torque compared to a turbo and it will burn more fuel then if you turbo it. But it's the closest to the responsiveness of an N/A motor that a forced induction motor can get.

What the hell has that got to do with anything?

The guy was asking about twincharging!

Also not much of that is even true.

[Blazin674]

so there is actually a block off to switch between the two? i think i might just save my money and keep the stock 4agze so i can go buy another trans am. the only thing i might do is a sc14 upgrade

[REN69]

Originally Posted by punter

What kit is that?? Thats a crap way of doing it IMO. The HKS kit switched between them, charger down low and turbo up top.

This one runs parrelel



and this one sequential

NVM, I was under the impression that the HKS kit kept the SC on at all times.

[punter]

Originally Posted by REN69

NVM, I was under the impression that the HKS kit kept the SC on at all times.

NO the HKS one switchs the supercharger off up high.

more photos.

[thespud]

The best way to do this is to get yourself a custom ECU Unit that will handle both. You may want to pick yourself up an SC with Electronic clutch (Will disengage at a certain RPM). You then set up a one-way valve system in the tubing.

This would work on the principal that when the Turbo is spooling and not at full boost, the SC will be pushing the one way valve shut, and the opposite occurs when the clutch on the SC is open and the Turbo is at full boost. I am in the process of getting a friend to engineer an air-tight one way valve system for this purpouse as i am looking to Twincharge my 20v Properly.

And yes: the HKS system cheats, and the SC is running all the time. This can be an advantage though, as you get much more air displacement running through to the engine, giving better fuel burn.

[punter]

From http://www.divisionone.org/sn/rebirth.html

For boost a EVC unit, and a SC controller by HKS was used to disengage the SC when the TO4 turbo takes over.

From http://www.twincam.org/forums/index....hks+twincharge

The HKS kit was shown in the edition of Fast Fours that compared the 2 red AE82s (20v Vs GZE).
The performance was understandably quite impressive, with a very smooth transition from super to turbo.

from http://www.twincam.org/forums/index....topic=15248&hl=

Yea I am in Japan. Yes the original HKS twincharge kit is rare. I was lucky to come accross it. There are alot of twincharged ae86's here that I know of but not sure how they controll the S/C. The HKS kit I have has a sensor for boost and shuts off the S/C when out of the S/C boost range.

Pretty sure that it switchs off......

[thespud]

I stand corrected. Maybe the ones i have seen have been a 'Fake' HKS Twincharge 'kit'. Silly people that i was taliking to. Still makes it more fun for me to design one from scratch

[epyon22]

look into megasquirt i just started it looks really good you can get exctly what you want for half the price an a little bit of sodering sounds like a good deal to me

[AVANT]

Since punter got it handled with the twincharging questions. I'll just comment on this.

Originally Posted by freakinbox

this was covered in initial d with 2 rx7's lol. I swear that show has the answers to everything car related
- Ok big turbo is more laggy, but more powerful. Also they will be more smog legal. usually 1 larger turbo rather than 2 smaller ones
Twin turbo is more resonsive, but weaker than a single turbo. Will be harder to keep smog legal.

Super Charger is the most responsive since it's belt drivin. Not as much torque compared to a turbo and it will burn more fuel then if you turbo it. But it's the closest to the responsiveness of an N/A motor that a forced induction motor can get.

Some of things you said are correct, and other parts 1/2 right.

1) A larger turbo will create more turbo lag.
2) There are 2 different methods of going twin turbos, sequential systems and bi turbo systems. A sequential system runs a smaller turbo and a larger turbo inline to get the best of both worlds (mid range and top end). A bi turbo system involves 2 identical turbos feeding to different cylinders.
3) There are different reasons for going with different turbo setups.
a) A single large turbo can make lots of boost up top to make lots of top end power, this option is generally only good for drag racers since the powerband is very narrow.
b) A single small turbo gives you quick spooling low end, but these turbos will run out of breath quickly giving a weak top end.
c) A single medium sized turbo, compromise between a and b.
e) A bi turbo system can produce a wider powerband than a single turbo of similar power output. Usually built for a very powerful mid range and decent top end.
4) A supercharger creates the most amount of low end torque because unlike a turbo, it does not need to be spooled (altho rpms still affect how much boosts a SC can produce). Superchargers are the best option for people seeking low end torque. However, superchargers are generally not as effecient as turbos (meaning they blow hotter air sooner), making turbos a better choice for top end seekers. A supercharger doesn't always produce worse gas milage than a turbo setup, it really depends on the tune and setup of the vehicles.

I don't understand your smog comments... what does the number of turbos have to do with passing smog?