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Rb26 Lag - Compression?

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My rb26 is extremely laggy, makes about 12 psi at around 5500rpm from memory, checked everything twice, thing is the compression is down, ranging from 135-118, would this be the cause of that amount of lag? only other thing that im unsure about is that its got split dump pipes on it and have never had anything to do with them


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checked base timing 3 times mate haha, no they are stock turbos not n1s, im from tasmania i dont have a cat lol, yes it does have adj cam gears, could it be possible its a combination of incorrectly set gears and the low compression?

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If its still got enough parts to run a stock ecu, put the stock ecu back in and see what that does.

The motors performance is only as good as the tune.

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Its got adjustable ones on it for some reason,had heaps of tension on them too

readjust the rod length of the actuators, may take a bit to get them right but it sounds like it should fix your problem.

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Most lag issues ive seen are because of air leaking from the induction side of the engine somewhere between the turbo's and the throttle bodies. I recommend blocking the hose from the twin turbo pipe to the intercooler with a plug and then pumping up the intake manifold with an air compressor and checking for leaks. You will spot most leaks with just a few PSI of pressure but you should pressure test to about 10psi above your target boost pressure.

If you find any leaks you should re-set your actuators to stock positioning, or you will end up overboosting on your first test drive and break off turbine wheels.

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ill check to see if its around 5mm duncan, yeah i blocked it up found a leak, fixed it and it made bugger all difference, also found an exhaust leak on number 3 cylinder from head to manifold where some champion had half broke the stud but i havnt had the car back together since finding that but i cant see how that would make that much of a difference really

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