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Nah lazy coils will cause misfires, not a straight power loss...

Plugs look fine, so long as the conductors are still in tact, and the plug isn't wet or covered in unburnt fuel.

Checked the BOVs yet? Start there.

BTW A small leak in a vac line won't flow anywhere near enough air for you to even feel a power loss.

ISMR's dyno is generally considered a low reading dyno and if you say your gtr is all standard, then a figure of 160kw atw isn't that bad.

From memory with my chats to Indy, standard gtrs will do around ~170kw atw on his dyno. What did Indy have to say about it ? Standard evos/stis only do around ~140kw atw there.

And how about reversing the mods ? Install the factory exhaust and remove the boost gauge and replace the tapped line with a new one, reset ecu and then test again.

ISMR's dyno is generally considered a low reading dyno and if you say your gtr is all standard, then a figure of 160kw atw isn't that bad.

From memory with my chats to Indy, standard gtrs will do around ~170kw atw on his dyno. What did Indy have to say about it ? Standard evos/stis only do around ~140kw atw there.

And how about reversing the mods ? Install the factory exhaust and remove the boost gauge and replace the tapped line with a new one, reset ecu and then test again.

indy said there is definately a problem, other cars of the same are making 10/20kw more

indy said there is definately a problem, other cars of the same are making 10/20kw more

Hrmm fair enough.. if it was myself, i wouldn't be worrying too much about a 10kw discrepency but if you say it feels much slower.

If it was me, i'd quickly chuck that factory exhaust on and remove the boost gauge, reset and test. Could be your ecu doing dicky things like the above mentioned. Checked intake/filter condition and cleared it out with upper engine cleaner? What's the air intake temp sensor reading when doing the dyno runs as that can affect ignition timing/power.

Edited by Touge Kyousou

My gtr with kakimoto exhaust, trust front pipes and apex pods made 160kw @9psi with the boost restrictor removed. Wouldn't boost any higher than that probably due to not having an ebc. This was at boostworx in adelaide which runs a mainline dyno I think.

well i was boosting up to 13 psi, sol it should be more than 160.. :D

Yeah should be near on 200kw at that power. Maybe try another workshop for a second opinion? As people of said it could be a number of things, take it to a tuner that specializes in GT-Rs if you haven't already.

i took it to Indy at is motoring, i have only heard good things about him, he does GTR'S all the time and he said that my power is definately down..

i will tick things off as i go

i am looking for a standard computer ATM

was it done in RWD?

have you done a compression test?

what position is the CAS at?

have you checked base ignition timing?

The Dyno was in 4wd

I have checked all those things

I guess I will take to a third mechanic and see if he can figure it out.

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