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Hey,

I have a L28E engine in my Z, the EFI setup came off a MR30 skyline.

There seems to be a bit of a flat spot before 1200rpm, i was wondering how one would go about tuning the EFI setup so i might be able to get rid of this?

I have no idea about early nissan EFI systems. I'm just trying to learn.

thanks

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https://www.sau.com.au/forums/topic/67870-r30-l24l28-tuning/
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Thanks For the Replys.

I have a feeling it is the TPS, however because this is the upgraded throttle body from a VL, TPS adjustment is a little difficult. I need to look at it some more.

Though in a recent test, I brought the revs up to about 3k, and disconnected the vacuum line to the distributor and it didnt sound like the timing had retarded at all. There was no real descernable difference in engine note. Dad is convinced its working, but i dont know. If it was stuck constantly on advance, i suppose it would explain why i have a lumpier (than i would expect) idle (or that could be the cam).

As for the differences between the ZX and r30 setup, the zx is alot more complicated, electrically, and slightly mechanically different. The r30 is good because the entire system is seperate from the rest of the cars wiring, and only requires 6 connections (and a couple of relays) to the cars existing system (its also a good immobilisation point). The 280zx was designed as an EFI car so the wiring is alot more intergrated, thus I imagine harder to retrofit into say a datsun 260z (like mine). i didnt do the conversion in my car, however the previous owner that did it, did a bit of a hack job (ECU sitting in the passenger floor well, lots of different coloured wires, lots of electrical tape) i have spent the last few months rewiring alot of the system. And its all good now, apart from this small problem.

Thanks For the Replys.

...Though in a recent test, I brought the revs up to about 3k, and disconnected the vacuum line to the distributor and it didnt sound like the timing had retarded at all. There was no real descernable difference in engine note. Dad is convinced its working, but i dont know. If it was stuck constantly on advance, i suppose it would explain why i have a lumpier (than i would expect) idle (or that could be the cam).

Whack a timing light on it and see what happens when you rev it.

LOL, Kirby, It sounds like you have emailed me from the future and you had purchased MY 260z :-) (ECU sitting on passenger floow, all different colored wiring, electrical tape etc etc...).

It makes sense that the L24 electrics would be easier to retrofit.

Thanks For the Replys.

I have a feeling it is the TPS, however because this is the upgraded throttle body from a VL, TPS adjustment is a little difficult. I need to look at it some more.

Though in a recent test, I brought the revs up to about 3k, and disconnected the vacuum line to the distributor and it didnt sound like the timing had retarded at all. There was no real descernable difference in engine note. Dad is convinced its working, but i dont know. If it was stuck constantly on advance, i suppose it would explain why i have a lumpier (than i would expect) idle (or that could be the cam).

As for the differences between the ZX and r30 setup, the zx is alot more complicated, electrically, and slightly mechanically different. The r30 is good because the entire system is seperate from the rest of the cars wiring, and only requires 6 connections (and a couple of relays) to the cars existing system (its also a good immobilisation point). The 280zx was designed as an EFI car so the wiring is alot more intergrated, thus I imagine harder to retrofit into say a datsun 260z (like mine). i didnt do the conversion in my car, however the previous owner that did it, did a bit of a hack job (ECU sitting in the passenger floor well, lots of different coloured wires, lots of electrical tape) i have spent the last few months rewiring alot of the system. And its all good now, apart from this small problem.

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