twin throttle body 2.3 20v

[WabTheKing]

working on an idea at the mo with a friend, on a n/a 2.3 20v we have added another throttle body on to the manifold at the oppersite end to the existing one, so long as the air feeding both of these goes through the one air flow meter should this work?

[S2 Ant]

I think it would need to have exactly the same flow thru both inlets, otherwise if there is a greater flow or pressure from one than the other then its likely to flow in the high pressure one and out the other due to the pressure difference i think.

[Graham]

I would have thought that it would work, once the air is in their, there is only one place it can go, through the engine, but the throttles would have to be identical in movement for tickover purposes, or one would have to seal completely to allow the ISV to work.

[mcandmar]

It might confuse the ECU as it monitors the throttle body position, the engine would get more air than the ECU would think possible at any given throttle opening. In theory twice as much if there are two identical throttle bodies.

What I always found curious is the sensor for the throttle position reads WOT when the small throttle body is fully open. But this is only half of the throttle pedal travel, the other half opens the large throttle body

Do you have an S2 throttle body spare? Curious to see if we could change the dual butterfly to a single choke throttle body. I wouldn’t be surprised if it did wonders for low down throttle response.

It’s an unusual idea all the same, if you get it going please keep us posted.

Mark.

working on an idea at the mo with a friend, on a n/a 2.3 20v we have added another throttle body on to the manifold at the oppersite end to the existing one, so long as the air feeding both of these goes through the one air flow meter should this work?

[jogi730]

Moving on from this idea, maybe better off trying one TB per cylinder? That could well work as each cylinder being fed same amount as opposed to air coming in from just 2 points?
Any thoughts?
Chris

PS> What would this do to fuel consumption?

[gavs20v]

Theres a guy on audifans (aspro i think) doing a throttle body conversion on his 2.0 16v coupe, very interesting stuff. Hes using Motorbike throttle bodies.
Nice one
Gav

[S2 Ant]

That idea would prob work well and is how BMW's work, would probably work well for distribution of air flow to each cylinder too

[S2 Ant]

Actually looking at what i wrote earlier that would be wrong as obviously the lowest pressure would be in the engine itself so air would be drawn in from both inlets.

[ottawa coupe]

ITBs are pretty neat but there's a coupla obstacles i think (from me just museing at my computer instead of working!) that need to be addressed. the first is, how do you meter the air? you could have a simlar layout as factory and use the original MAF but then, due to the length and routing of the intake, you'd probably negate any benifit of the ITB. the other thing is that you'd, at the very least, want to re-map to get the proper mixture, some form of standalone would probably be better.

[Audi_CQ]

working on an idea at the mo with a friend, on a n/a 2.3 20v we have added another throttle body on to the manifold at the oppersite end to the existing one,

Why?

[WabTheKing]

Why?

ive pleaded with him to get an s2 but its like talking to a brick wall, i am just assisting him in his development,

[Audi_CQ]

My point was that's of no use to mount another throttle body. The original one is large enough so there would be no powergain. An easy way to check if you got any restrictions from airfilter to manifold is to use a vacuum gage. Check pressure in manifold on full throttle and compare with pressure in free air. If no difference there's little to be gained with other filter and larger (second) TB.
Separate throttle bodies would help some, but probably not justifing the cost.

Cheers,
Roger

[WabTheKing]

the car owes the guy nothing and nothing has been bought to do this as i had all the parts to do this as i had 3 7a engines so just playing with ideas really, we have another intake manifold if it doesnt work so nothing would be lost, at the end of the day he who never tried never succeeded! im only 21 therfore have alot to learn and theres no better way of learning than from experiance (so everyone keeps druming in to me)

[WabTheKing]

right, we have come to start the car, (in standard set up) but no spark at the coil, fuses under the red motor cap all ok,feed going to the coil pack, dizzy isnt alined would this make a differance to the spark from the coil pack?

regards
will

[porkkis]

Dunno 7A but 3B must have the dizzy aligned as the hall gap is used as a gate for the flywheel BTDC sensor.