Query About Possible Misfire @ High Revs?

[DeeUnit]

Hey there,

First time poster, just wanting to ask a question or two.

I am looking at this car:

http://www.trademe.co.nz/Trade-Me-Motors/Cars/Nissan/Skyline/auction-356498641.htm

Have driven it a couple of times, but have noticed that when changing from 1st to 2nd at high revs under load, it 'misfires' (aka car chugs back and forth for a split second), seeming to miss a beat, but then hits back and carries on like nobodies business.

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That is the info via the ECUTorque cable we have, graph indicates travelling from 1st to 3rd.

This is the only niggling thing which is preventing me from buying the car.

A couple of things that the owner has mentioned:

-Chipped ECU

-RX7 Injectors

Now those two things should indicate a problem, but where I do not know.

Do any of you guys have any idea as to what I should be looking for? Best and worst case scenario? Should I just stay away from it and keep looking?

Cheers for any help,

Damien.

[browneye91]

Also another thing to look at Holden coil packs?? Never heard of that before

[DVS JEZ]

It needs a better tune.