Physically, my Exige looks like it would be setup very well for individual throttle bodies. There is even a one off by Trial (more info)



But I do have some questions about ITB's, that wouldn't normally show up in discussion here, but you guys might know an answer with the vast knowledge here.

All Exiges are equipped with electronic throttle (that Trial one is converted to cable). Can you still use e-throttle on ITB's? Do you basically use the same linkage, just remove the return springs and let the motor directly actuate them?

Now the other problem. The Toyota 2ZZ-GE uses a MAF setup. Is there any way to use MAF on ITB's? I figure you can put a plenum around the ITB's to meter total air being pulled, but wouldn't that kind of negate the effects of ITB (or rather make it even harder to tune)? It seems like a MAP conversion would be the most practical...well not practical, but most succesfull method.

The intake ports on the 2ZZ come up at a pretty high angle. So that would help line up the ITB to naturally point up, where I have a ton of room thanks to the fast back design of the Exige. However I may still want to curve them up as shown just to make them point a little more up so that I don't ITB's opening directly to my ear thats 8" away

Would that long intake port affect the tuning length of the runner? Requiring a shorter than "normal" runner?



If you notice the stock intake manifold uses round tubing and it comes out fairly straight, so I would imagine welding the flanges for the ITB's would be pretty straight forward to the manifold flange.





Heres my dyno so far. Some midrange grunt would be nice, but so would maintaining that torque out to 8000 RPM.



From what I have seen, even adding cams to these engines (on Celica's) gets more torque, but it always starts falling off at the same point. So it makes me wonder if Toyota made the intake manifold have a nice resonance at around 7000 RPM to balance easy to drive and all out performance. Celica owners are limited by intake designs though because of hood clearance.....I don't have a hood



PS, with the open mesh engine cover, I bet it would sound freakin awsome on my car (just to get the REAL reasons cleared up )

 

I think your problem can be solved either way, a map or maf..however u must create a vac box for the itbs to successfully work.. the maf/map could put plugs into one of the serverval hoses in the vac box showing the correct readings i think this alone would help solve a major dilmmea.

 

MAP would definently work that way, but I think MAF actually has to be in the path of the air. Now if you could a MAF sensor thats kind of low profile like a O2 sensor and just thread it in and let it sample that might be cool...

 

I guess another way would be to find like a 45mm or 50mm MAF and use it on one of the runners. Or maybe two of the runners and average the voltage....don't know if the air flow would oscilate on one runner as the intake valves open and close.


Modified by Westrock2000 at 2:57 PM 5/21/2007

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Westrock2000 &raquo;</TD></TR><TR><TD CLASS="quote">I guess another way would be to find like a 45mm or 50mm MAF and use it on one of the runners. Or maybe two of the runners and average the voltage....don't know if the air flow would oscilate on one runner as the intake valves open and close.</TD></TR></TABLE>
bad idea..ur obstructing the air flow..into the cyl..so nono

i think coverting, from what your saying, is goin to be your best bet.

 

http://www.prototyperacing.com/
Talk to Joe, he may have a few ideas.

 

Can you not ditch the e-throttle?

After that, use something like AEM EMS to run a speed-density setup, and tune what you can with MAP vs. RPM, then set it to switch to TPS vs. RPM.

- Derek