1987RX7guy

iTrader: (3)

Hey all after the past thread with injector placment I ran into a company that does individiual throttle bodies that can be adapted to fit on a turbo rotary. I have several questions and things I am wondering about. First there are two places I can get the throttle boddies that I know of, tweakit and TWM. But only tweakit has a turbo plenum for running them on a turbo charged car. I liked the ITB's from more than a year ago since I was just an N/a guy but the thing that re-sparked my interest is that they have a setup for turbo's . I also like the fact that the intake tract is shortened somewhat although that is a double edged sword. :/ First of all if any of you all used these it would be cool to see some pics of the setup. I also thought it would really unclutter the engine bay as its a really simple setup and looks nice too. I was thinking about retaining the stock primary fuel rail setup with a set of 680's(swapped to an S4 rail) and having quad 680's on the throttle bodies and running a separate line for them from the fuel tank. With this I think I could support my power needs since it is equal to 720's in the primary spots and 1320cc injectors in the secondaries.

The big sticking point for most will probably be the total cost of the setup which is ~1000 dollars. But hit this up with any comments you have about it.


Santiago

NZConvertible

This is a pretty common set-up for high power turbo rotaries in Australia. Note high-power. Given your power goal I would doubt whether the gains are worth the considerable extra money and the other downsides of this set-up. This isn't something that should be done just for the bling factor (or "uncluttering" as you call it ).

The Rotary Webring would be a good place to start looking for more info, as there are a lot of Aussie cars there. Check out the Aussie workshops too.

1987RX7guy

iTrader: (3)

Um so 400whp isn't high? damn you must mean something like 800hp or something? I didn't ONLY want it for the nice look I wanted the gains from having a better intake. But the price is kinda steep its a little over 1k dollars for all of it up to the turbo plenum. Then all I have to do is add the injectors and connect the IC pipes and rig up a TPS somehow. I would also be guessing I should start looking at how to plum an air temp sensor since it won't come with one installed.

EDIT what are the down sides to it?

carx7

iTrader: (31)

Mind posting a link so I can see what you're talking about? I have talked to several Aussie companies about aftermarket intakes... but I wanted to see exactly what you are talking about before give useless advice/input.

-Chris

Bebesito21

you mean like this? http://mazdadragracing.com/intake.html

1987RX7guy

iTrader: (3)

Sure:

NZConvertible

I've seen 600hp 13BT's using the standard intake manifold, and you may remember this thread about aftermarket intake manifolds and the minimal gains from one example. There are pics of the set-up you want in that thread too, plus some more links.
Don't forget the aftermarket fuel rail and fuel pressure regulator, or do they come with the TB? Some do, some don't.
Those short, fat runners are good for top-end power, but you loose some torque down lower. Since the Aussies tend to do this to 900kg RX-3's and the like, it's no big deal for them.

sub9lulu

iTrader: (7)

i remember the 20b TB is good enuf for HIGH power ...

White_FC

Stock FC TB's quite possibly have more flow potential than two 50mm throttle bodies (which seem to be what was pictured earlier).
The inlet manifold however has much smaller runners than a webber manifold, also is longer which arguably might give you more power high up in the revs.

dr0x

Just get a fd UIM/tb assembly and port/polish it, then rig it up to your car.

carx7

iTrader: (31)

^ I hear this often but have never seen proof. Do you know something that I don't? I'm asking, not being sarcastic. There is an assumption that the FD manifold makes more power than the FC parts but I have never actually seen this. If you have dyno graphs I would love to see them.

As for the other parts. I think there could very well be a better solution to the stock intake manifolds. Most of the aftermarket manifold seem to be designed with drag racing in mind. That certainly doesn't mean that a better solution doesn't exist also for other types of driving that want better mid/low end power.

NZConvertible

The FD TB is 15% bigger than the FC one, but you need to be making a lot of power for the difference in power to be worth all the effort of swapping. From memory (someone correct me if I'm wrong) Soul Assassin picked up ~30hp from the swap (~600hp), but on a mild engine you wouldn't get near that much. I'd be interested to know the effects of losing the FC's plenum chamber (the FD UIM has no plenum).
I think you'd be hard pressed to beat the factory manifold for mid/low end power, as this is generally where manufacturers design their manifolds to work best. And any improvements you did make would almost certainly be at the expense of top-end, so I doubt anyone modifying for performance would be in the slightest bit interested in that.

carx7

iTrader: (31)

Didn't know that but not surprised.

I have heard 25 HP to bring the car up to 625 with a ported FD UIM... to me this is worthless hearsay. That's roughtly a ~4% increase in power. I have also heard gains of ~4% from porting the stock FC parts. I tend to think of the FD UIM as an asthetic mod and that's it. I haven't seen any actual dyno graphs to say otherwise. Being interested in squeezing out the last bit of performance from my setup, I am planning to do a dyno comparison of the two. Run the car, swap it out and run it again... while trying to maintain simliar test conditions... but that isn't my top funding priority right now. Maybe in a few months.

Agreed

Quite possibly, just haven't seen anyone speak up and say that they put an honest effort into trying such a thing... I may give it a try once the body work is finished.

bcty

fc tb over here has been proven to be good till 700ish hp till it starts to fall on its face

oregano

iTrader: (1)

what rpm range duz an intake manifold (like the pictured above) start making power gains?

J-Rat

iTrader: (2)

C,

I can call him and ask if you like.

Jarrett

carx7

iTrader: (31)

That'd be cool Jarrett. Find out exactly what it was. Was it port matched to the S5 lower? Ported UIM? ported TB, what exactly was the power gain? what else was changed? tunning or any other part of the system?

-C