Individual Throttle Bodies
 

Well, I was really board last night and I came across these Throttle Bodies on ebay...

Ebay link TB

I was wondering if any one has ever you these or another brand/company like them on there NA or Turbo motor? Is there really any power gains? Or just a more responsive engine? I also assume you will need to run a After market fuel computer, would a Apexi SAFC run this just fine? Or do you need like a Halteck? Any help, or info would be much appreciated!

No one has ever used IND TBS on there rotary guess?

Damn, dude- I was JUST looking at these and was going to post a big ass post when I came upon yours- I will keep an eye peeled for a guru's response. Seems to me some guy posted not long ago about using a couple of motorcycle throttle bodies, don't know what happened to him. Guess I will try and search...

Penguru is using the TWM TB on his Haltech equipped car. Maybe he will share here. Or you can go to NOPISTONS to talk to him. BTW, you can get better prices than that EBAY auction. John

I know they are based in Australia, but other than that, no dice...

Re: Individual Throttle Bodies
 

You will need a Stand Alone ECU (haltec, microtec, wolf 3d, etc. I wiould rather go with the EFI carb setup just because of the need for a RB inatake manifold or somehting similar!

KNONFS, So you can't go the cheap way with a Apexi SAFC or HKS AFR?

All a "piggy-back" does is modify the ECU signal, it has no controlling/generating capabilities

I've seen those babies...Very sweet. Technically, you could pipe the AFM into a Y pipe, which would then connect to the throttle bodies. So you could run the stock ECU. Not sure why you would want to do this, since the gains from the IDA bodies are because they are so damn free flowing (but you're going to kill your low end due to such short runner lengths).

Edit: and you really need a large port job (huge street, bridge, peripheral :) to take advantage.

IMHO This sort of setup is vital if you want to get the best from your car, NA or boosted. Yes it needs a new fuel computer, but the megasquirt is well proven on the 12A and 13B and is only $120 plus soldering time. And if I ever get off these forums will have spark control for the rotary as well.

I've been fighting a recalicitrant dry sump system recently but should have my Westfield back on the road very soon. Gimmie 1000 miles and I'll get some dyno data. Expecting 210-220 from a pre-85 13B 4-port running 50DCOE TBs on a custom manifold. Stock and on a DCOE carb I was getting 140 at the wheels, and that was with an inlet a foot too long.

Australia is the place to go for IDA setups. Injection perfection do very nice stuff as well as the ebay lot. If you are patient it can be cheap. My intake has ended up costing around $250 all in, but the pain, swearing and cursing has made me wish I had just bought the kit....Come to think of it the dry sump has done the same.

As and when I decided which engine will go in my FB then I will be getting a bike TB adaptor made up. Currently umming between dropping in a new T2 block I have and running that NA or using that block as parts to build up a screaming 6-port. Now that I know 250HP is possible out the 6-ports I am sorely tempted, but as ever its time and money.

Oh my toy:

Aaron Cake, is there a way to counter at the loss at low end? The only thing i could guess would be avriable intake runners, but i doubt any one makes them or has money to actually do someting like tah over the cost of just turboing the car.

I would assume it would be the same for a turbo if you used ITBs.

Do you still use the stock ecu with like a Haltech or Motec etc? Or do you just like throw that away? I am just confused why you could not use Apexi or HKS, or is it just the fact that you cannot control it as much?

I had just thought of something else, would you gain anything by mounting ITBs to the stock lower manifold? Or is that just a waste of money?

www.japperformance.com do such an adaptor for a stock lower.

As regards loss of low end, it really depends what you are optimising for. With the 6-port engine there are some options for having different length runners that would use seperate throttles for the aux ports.

But on a 6-port if you use ITBs you can get 230HP. If you increase the lengths of the runners to get more midrange your peak will drop by 20HP.

There are no free lunches out there. If you really must have the maximum torque at 2000RPM you need to stick with a stock system and accept that you are well down on the engine's potential.

On the ECU front you can leave the stock unit running spark and just use an add-on for fuel.

my method for countering loss in low end due to short runner will be an extra rotor :)

Can you enlighten me? or would it be more like having say 3 TBs in stead of 2 TBs? Now as for the 230hp, would that be with the stock LIM or just with a downdraft and ITBs?

Is there a way to stilluse the VDI to help with lowend and while using the stock LIM, I can't remeber of hand what part that is mountedto..

I've been toying with a number of options on this. Current favourite is a 5 throttle system:

1 on the primaries
2 on the secondaries
2 on the aux ports

Smaller bike TBs are 38 mm, which lends itself nicely to this. If you look at the euro 6-ports, instead of a sleeve, there is a 28mm butterfly on the aux ports. However it takes up about half the port area even when open. Moving the butterfly further upstream makes this restriction much less (aside: euro ports are operated by manifold vac, not back pressure, as we didn't have cats on the 2nd gen cars at all).

Now the devil is in the details on this, the details being, how to operate the throttles so they open at the right time and how to tune the inlet runners, especially the secondaries such that you get best of both worlds.

I am a fan of electronics, so am seriously considering using fly by wire controllers on all bar the primaries. I haven't yet worked out how to do all the runners.

You then look at the torque curve for the racing beat street port that was featured in dragsport and realise that 90% of peak torque (162lbft) is available over a 3000RPM band and you start to wonder if the complexity is worth the gains. The no free lunch rule kicks in again.

I'll build it one day for the hell of it, but mainly because it will allow outrageous timing on the aux ports