Converting To Single Throttle Body

[skylinekid]

hey everyone wen converting a gtr from 6 throttle to big single throttle im very unsure if u have to sumhow strip the 6 butterflies out of the 2nd part which attachs to the head or do u take that whole piece off all thogether cuz that main part is where water is delivered to ur engine which im very unsure wat u have to do???

[infamous_t]

Why?? Get new plenum(Single TB) if you want single throttle body.

[skylinekid]

well for one i will be running an apexi powe fc d-jetro word is they have trouble tunning them with the 6 throttle setup hence y i want a single throttle body setup and i want the apexi bcuz its the cheaper option to still be able to have a heads up display to keep a close on on knock......

and on closer inspection the throttle bodies are actually seperate from the other part of the manifold so yeh i guess that solves that issue

[2BNVS]

ive seen a couple 700hp gtrs runnin stock inlets with the Jetro, shouldnt be that hard to tune with the right knowledge

[skylinekid]

orite well i havent really looked much but ive just been informed of the issue by one of the tuner i know... he works for motec...

will have to ask a few shops wat there recommendations are on the matter

[infamous_t]

True, its harder to tune the ITB setups, but not impossible, theres gains to be had by keeping it... mainly response.

[W0rp3D]

heads up display to keep a close on on knock......

i may be mistaken but isnt one of the down sides of the power fc that it does not use the knock sensor?

[R31Nismoid]

PFC is one of the ONLY ECU's that uses the factory knock sensor to display a readout, its the upside of MANY ECUs.

And as for the motec/tuner/whatever - obviously he isnt as good as he thinks if he is saying it cant be done

[Adriano]

PFC is one of the ONLY ECU's that uses the factory knock sensor to display a readout, its the upside of MANY ECUs.

Yes, but the PFC doesnt do anything about it, so unless you hear knock and keep into it whilst looking at the hand controller, or watch the hand controller whilst the car is driving, its not really much good unless you have datalogit. If you are running stock cams, there is no reason to go single throttle, the d-jetro will run it fine, just hook the map sensors up exactly as the instructions say.

[R31Nismoid]

If you are "hearing" knock... then the tune is simply shithouse and the tuner should be replaced quick smart.

I have never "heard" knock in any of my motors in 5 years. Its reached 40-50 on some occasions due to a cell (or two) being out, but that's it.

Any more than that has been due to too much ignition advance by my own doing.

Whilst the PFC doesn't retard like a stock ECU would, a decent tune would not reach that limitation at all.

[Adriano]

But hot weather and/or a bad batch of fuel could certainly do it

[W0rp3D]

But hot weather and/or a bad batch of fuel could certainly do it

Unless it was a race car (in which case it would be tuned for the conditions of race day anyway) then i would expect my tuner to allow a safety margin for atleast the weather which should also account for a dodgy batch of fuel.

Or maybe im just expecting to much??

[Adriano]

Expecting way too much, if you tune it on 98 RON, and put 91 RON in it, it will knock. If you have a 91 RON tune, then no point running 98 RON, there can be 6 degrees of full load ignition timing between the two tunes.

[W0rp3D]

i am assuming that it is tuned on one ron and only used on one ron, mine is standard but i always use 98 anyway.

do bad batches of fuel get bad enough that when filling up with 98 that it can actually be as low as 91?

[TiTAN]

PFC is one of the ONLY ECU's that uses the factory knock sensor to display a readout, its the upside of MANY ECUs.

Yes, but the PFC doesnt do anything about it, so unless you hear knock and keep into it whilst looking at the hand controller, or watch the hand controller whilst the car is driving, its not really much good unless you have datalogit. If you are running stock cams, there is no reason to go single throttle, the d-jetro will run it fine, just hook the map sensors up exactly as the instructions say.

You don't have to be looking at the power FC controler to see if there is any knock, if the reading goes over 60 it flashes the "Engine check" light.