Twincharging a turbo car

Hi guys. New to the site but lotta info here. I've got a '99 Honda Civic Si with a Jackson Racing SC installed. Running 5-7lbs boost right now. Considering twincharging. Seems like a great option to drastically increase my performance. Looking to install an LHT intercooler to keep SC temps down and a water/meth kit to further decrease temps and increase octane allowing me to get more power on 93 octane. It's a 1.6L engine and I know I have to size the turbo as if its a bigger engine, any idea what size to run?
I would say something like a Garrett GT 3076 would fit the bill :), should have the potential of 500bhp, but you'll have to make sure the engine is up to it.
 
Yeah, i'd be happy with 400-500. Surprising how many people talk down about twincharging, but its seems extremely beneficial. I do plan to upgrade internals with forged pistons and rods, possibly crankshaft if that much power requires it. New valve train as well and cams. Any suggestions on compression to run with this set up?
 
Been looking at eventually running a compound system in my old diesel... :) Seems reletivly easy. As there is no throttle, is the forced air constantly running and making boost from both the SC and turbo?

Doing a supercharger and turbo on the 306 should be straight forward as there's plenty of space between the engine and radiator it will be the belt routing that needs looking at....

Does yours have air con Dave?
 
Doing a supercharger and turbo on the 306 should be straight forward as there's plenty of space between the engine and radiator it will be the belt routing that needs looking at....

Does yours have air con Dave?


Yes... I can take the AC pump out which will make me room for the SC and its belt placement, belonging I dont run a massive pulley! But.. Don't smaller pulleys mean more power when SC are concerned?
 
Yes it does mate,

On AC models the power steering pump is up by the coolant header tank, on non ac models its down below the alternator, I'd switch to this setup,

Does your AC work Dave?
 
Okay... Makes sense I guess. Looks like an Eaton M45 charger looks like it will be simple to plumb in, with the manifold off of a Merc.
 
Yes it does mate,

On AC models the power steering pump is up by the coolant header tank, on non ac models its down below the alternator, I'd switch to this setup,

Does your AC work Dave?

Sure does.... doesn't beat the feeling of sticking your head out the window though.... ;) :lol:

It does look easier to compound charge a ph1 d turbo. So... Remove the AC pump then locate the power steering under the alternator? Surely that would that would cause timing issues?

If I can get my hands on a DHX engine, that issue will be sorted, anyway...
 
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Sure does.... doesn't beat the feeling of sticking your head out the window though.... ;) :lol:

It does look easier to compound charge a ph1 d turbo. So... Remove the AC pump then locate the power steering under the alternator? Surely that would that would cause timing issues?

If I can get my hands on a DHX engine, that issue will be sorted, anyway...
??????????????
 
Just read what I said... I was in a rush at work.

What I mean is.... Will the supercharger prevent the alternator from charging, as I would have changed the formation of the pulleys? Looking at it, would the idler fail? 'Timing' is quite a general term.
 
How would the supercharger prevent the alternator from charging?
and what do you mean by "Timing is quite a general term" ?
 
Sure does.... doesn't beat the feeling of sticking your head out the window though.... ;) :lol:

It does look easier to compound charge a ph1 d turbo. So... Remove the AC pump then locate the power steering under the alternator? Surely that would that would cause timing issues?

If I can get my hands on a DHX engine, that issue will be sorted, anyway...

You've got a lot to learn my young padawan...

No it won't cause timing issues, the Aux belt "circuit" is independent of the main cam/timing belt,

and the phase 2 setup is easier as you can move the header tank, where as the phase1 its built into the radiator so you have less space....
 
How would the supercharger prevent the alternator from charging?
and what do you mean by "Timing is quite a general term" ?

To make the supercharger fit in my car, it will have to be before the alternator, meaning contact wont be great.... I suppose when I was first tinkering with cars, everyone I knew used timing as an excuse to describe something that went 'wrong', if that makes sense. Basically, I was told otherwise.... So in other words, wrong. :embarrest::embarrest:
 
You've got a lot to learn my young padawan...

No it won't cause timing issues, the Aux belt "circuit" is independent of the main cam/timing belt,

and the phase 2 setup is easier as you can move the header tank, where as the phase1 its built into the radiator so you have less space....

Sorry I thought it was the other way around.....

:embarrest::embarrest:

Now I am embarrased! I am here to learn!
 
Whats the best compression ratio for a twincharge setup? They say low compression when boosting but i've also heard SC needs slightly higher comp in order to wirk efficiently.
 
Whats the best compression ratio for a twincharge setup? They say low compression when boosting but i've also heard SC needs slightly higher comp in order to wirk efficiently.
Boosting is boosting, doesn't matter whether it's Turbo, Super or both, you should lower the CR if you are going more than about 6psi boost.
 
How low? 9:1? 8:1? I know somecars are running high boost and compression but that lessens engine life correct? I know if you lower compression too much with turbo you lose alot of low end power. But with the super you shouldn't have that problem...
 
I dont think a higher c/ratio in itself lessens the life of the engine its what a H/C does

It can alter the knock level quite dratstically as does higher boost and too much at full load and you can have a dead engine

How low you need to go varies on the engine charchteristics but if it is running high boost you probably dont want higher than 8 : 1
 
It's a common upgrade to Pontiac Grand Prix's here.
20111231100745.jpg

http://www.youtube.com/watch?v=ywifp93AB9k

A few links I was able to find on the subject in the American W-body scene:
http://montecarloforum.com/forum/nitrous-super-chargers-turbos-tuning-14/twin-charging-21689/
http://www.fiero.nl/forum/Archives/Archive-000001/HTML/20110502-2-108196.html
http://www.clubgp.com/newforum/tm.asp?m=5241803
http://www.clubgp.com/newforum/tm.asp?m=5044761&p=&mpage=1&tmode=1&smode=1&key=twin%2Ccharged&language=single

This may be more relevant to you though (seeing as how the L67 is supercharged from the factory)
http://forums.vwvortex.com/showthread.php?3874370-supercharger-w-turbocharge
http://forums.vwvortex.com/showthread.php?3684675-Twin-Charge
 
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Hello!
Glad to find a forum where twin-charging is not like "i-won´t-talk-to-you-any-more" |B

I´ve got an old toyota celica, and plan to twin-charge it (just for the kick of building). Now i´m in search of information for the best concept. I think the best way would be a serial charging,Turbo->SC->Engine. But there is really no room left to fit two intercooler in my car. So I think about a parallel setup, feeding both turbo and SC into one big intercooler. I can get a big turbo so i will achieve same boost levels like with the serial conecpt.

I know I need some valves to prevent the SC boosting the turbo and vice versa, but that shouldn´t be a problem. Just a T-piece with a flap inside it, the one with higher pressure will win. That way I will get a smooth transition between SC and turbo, a "wastegate" at the SC side will prevent the SC from crushing against the wall. Also the engine management will be simple, because the ECU don´t have to care about the charging system, will see boost like on a stock engine and can control the turbo like any stock turbo system.

Sounds good for me? Are there any downsides of this concept, except the bigger "turbo lag" compared to a serial system?

Thanks and best regards,
Andi
 
Relocate the battery to the rear of the car to free up space. The aircon pump is often sacrificed to add the supercharger.

The parallel setup is just two streams of compressed air. The serial setup is much better if you can make it work.

Proper twincharging compresses the already compressed air further which is where there is a big win.

One benefit of the parallel setup is that you get supercharger power and low revs and turbo power at higher RPM - the best of both worlds.
 
Hello and thanks for the welcome :)

Yeah the battery is already in the rear, so i have space for an electronic steering pump. Now I can place the alternator at the backside of the engine and the supercharger over it.
I´d like to keep the aircon, black car and summer.. :cool:

Yeah the serial setup would be nice, but the tranny will not make that much boost. What i´ve read the limit is at around 500NM, and that can be easily reached with a bigger turbo. So multiplying the boost is not really the goal, but killing the lag. And that will work with a parallel setup, it will also help spinning the big turbo much earlier right?

Thanks!
 
Yeah the serial setup would be nice, but the tranny will not make that much boost. What i´ve read the limit is at around 500NM, and that can be easily reached with a bigger turbo. So multiplying the boost is not really the goal, but killing the lag. And that will work with a parallel setup, it will also help spinning the big turbo much earlier right?

Thanks!
That makes sense to me. I see where you are coming from.
 
Hello all new here :) ive got a 96 3800 N/A from a firebird thats going into a 79 Datsun 210, i had looked into just doing a turbo or just a sc since they are so easily available for this engine but i got excited to learn you can twincharge hahaha so here i am.

Just a few questions;
1:would you recommend upgrading the internals when doing a twincharge set up?

2: still a little confused on which is better sc turbo engine or turbo sc engine ive read all the above just still not sure?

3: what rear end ratio would you recommend after doing this to this engine? (i have the whole drive train from the 96 bird motor to axle)
 
If you increase the power by a wide margin you should strengthen the internals of the engine and i'd also recommend dropping the compression ratio as well which allows you to run more boost. Water injection can help out with detonation issues here as well.

I would personally put the SC first then the turbo, the turbo can make more power compared to the supercharger and you'll get a better throttle response low down with the supercharger first as it won't be dragging air through a slow spinning turbo. I don't really think it matters too much though in the real world. Engine bay space and pipe runs are the limiting factors with these setups and pretty much dictate what you have to do.
 

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