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Optimum Vtc Setting For R34gtt Neo

driftmeister

By driftmeister,
in Engines & Forced Induction

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driftmeister Community Regular

driftmeister

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Hi Guys

Im now tuning my PFC and trying to work out the Optimum VTC setting for R34GTT with a slightly laggy T04E turbo. To compensate the low rpm load before the turbo get spooling at fullboost around 4k rpm, can i set the VTC like 3500 rpm and will it do any damages if it were set that low? Still stock cams but with adjustable cam gears for exhaust side only (slightly retard settings).

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rob82 Mentor

rob82

Posted
Posted
Hi Guys

Im now tuning my PFC and trying to work out the Optimum VTC setting for R34GTT with a slightly laggy T04E turbo. To compensate the low rpm load before the turbo get spooling at fullboost around 4k rpm, can i set the VTC like 3500 rpm and will it do any damages if it were set that low? Still stock cams but with adjustable cam gears for exhaust side only (slightly retard settings).

Run the car up on the dyno with the VCT off then with it on, note the rpm at which the dyno graph cross over and set it at that - you could run full advance till the rev limiter and not cause damage.

driftmeister Community Regular

driftmeister

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Today i tried setting at 4000rpm for road tuning (since i hv wideband), car felt very lively and more spirited in town driving. Felt like VTEC effect especially when downshifting or upshifting the rpm will just drop on the sweetspot.

Just wondering whether VTC helps more on low or high load? Would consumption suffer at the setting im running now?

Not planning on doing any dyno runs atm, until i upgrade injectors and cams.

Edited by driftmeister
Rolls Grand Master

Rolls

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Run the car up on the dyno with the VCT off then with it on, note the rpm at which the dyno graph cross over and set it at that - you could run full advance till the rev limiter and not cause damage.

Make sure to do several dyno runs, one at 25,50,75 and 100% throttle and note the cross over points, put the change over at the mid point of all 4 cross overs.

Another option is to set up a 2 dimensional VCT activation mode, eg TPS (throttle position) and RPM to get he maximum effect. I do not know if PFCs allow you to create custom 2D maps from two inputs to control an output though.

Certainly be interesting to know your results if you do do this though.

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