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Got a mates s13 which has a stock rb26dett and ECU. It idles fine and free revs fine. When driving flat foot it seems fine but is slow. When driving at constant speed and boost is around 0-5psi it starts to surge bad. Like when you back off the throttle with no BOV how the air rushes back into the turbos but it happens continuously while on the throttle. Cam timing is correct but for 20 degrees ignition timing the CAS seems to advanced. It back fires a poop load.

Any thoughts. Its a real pain in the arse to drive.

Dave.

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Well i pulled both turbos off today. Front is fine but the rear has lost its wheel completely. Did a compression test before i drove it home with a blown turbo and all come up at 160 -170 but #6 was 112 :D Will do another one later in the week.

Car ran like absolute shit, haha. My guess is O2 sensor sensors are buggery too. Had been running rich for a while before the turbo went. Mate has no cat in it either :/

So im thinking my mate should. Get a set of decent 2nd hand n1 turbos, new o2 sensors, new plugs and a cat.

You think it should be fine with having only #6 cylinder that low on compression??

Does the ECU need the sensor that taps in the exhaust around the middle of the car?

Edited by Ganador
Well i pulled both turbos off today. Front is fine but the rear has lost its wheel completely. Did a compression test before i drove it home with a blown turbo and all come up at 160 -170 but #6 was 112 ;) Will do another one later in the week.

Car ran like absolute shit, haha. My guess is O2 sensor sensors are buggery too. Had been running rich for a while before the turbo went. Mate has no cat in it either :)

So im thinking my mate should. Get a set of decent 2nd hand n1 turbos, new o2 sensors, new plugs and a cat.

You think it should be fine with having only #6 cylinder that low on compression??

Does the ECU need the sensor that taps in the exhaust around the middle of the car?

by the time you find and buy the used n1 turbos you might as well have just saved time and ordered some new garret bolt in replacements.

Ouch that's not good. Probably just needs hone and rings but if you go through that much effort, for $2500 can buy forged rods pistons head gasket and bearings from spool.. Good for a long time then.

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