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A tuner wants to install a spitronics ecu, he suggested to install a single large throttle body on MY RB26DETT which currently has 6 ITBs, he also will do away with the MAFs,He is going to upgrade my turbos with steel shafts, he promised me between 350-400kw after he his complete. Will my throttle response be affected by going single Throttle body? Is this recommended?

Yes throttle response will be (negatively) affected by doing that. It is hard to get any better throttle response than what you get from 6x ITB.

I wouldn't do it. If he needs a vacuum signal to run a MAP sensor, he could use the existing tapping points on the runners to get it.

supposedly it's easier to tune with a single throttle body rather than the ITBs. RIPS here in nz uses a single for almost all of builds.

But they're mostly massive power engines destined for the drag strip rather than street or track.

Laziness. The myth of easier tuning goes back to the 90s in Japan tuning with shitty add on HKS modules and not being able to deal with AFMs. They'd convert to MAP, and single throttle to achieve it.

This is no longer true. People know how to swap to bigger AFMs, how to tune with them, etc etc. No point in removing ITBs.

Laziness. The myth of easier tuning goes back to the 90s in Japan tuning with shitty add on HKS modules and not being able to deal with AFMs. They'd convert to MAP, and single throttle to achieve it.

This is no longer true. People know how to swap to bigger AFMs, how to tune with them, etc etc. No point in removing ITBs.

so are you saying afms are

in some way better than running a map sensor?

In some ways, yes, in others, no.

I run a map sensor just in case a cooler pipe pops off, my car will keep driving. This becomes more of an issue the higher boost you go.

AFM's are better at metering small changes in air velocity, and can be easier to tune for some. They will let you know if there is an intake leak by ruining the tune and running rich.

Why not run both? I do. :P

post-63525-0-39629700-1390185725_thumb.jpeg

which one does your ecu follow as the master sensor?

Map atm, but I have tuned with both before, AFM to 2psi them Map. It worked very well.

The auto gearbox needs the afm signal for line pressure adjustment...

I wouldnt even take the car back .If the guy cant tune an ECU with multiple throttle bodies, or is in any way scared of them, then hes not up to the task.

As has already been said its an old school thing that has no bearing on todays products.

I would use a MAP sensor only because, in my experience, they are less likely to fail. For some reason i have seen quite a few dud AFM's

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