Rb20det Problem

[lawler]

Ok mates has a silver top rb20det in a r31 s2 silo.

If you flaten it it comes onto boost it bogs down until 3500rpm then takes off then hits a wall again at 4800rpm we have tryed new plugs gaped at .8mm, cleaned air flow meter (also tryed a diffrant air flow meter) new fuel filter and r33 fuel pump but still no diffrant. also if you free rev it it limters at 6200rpm but dosnt sound like the proper limiter

Anyone have any ideas what to look at next

All thats done to it is cooler, full 3inch exhaust and 12psi (some times 14psi)

[Rekin]

tried new coilpacks? Cracked/worn coilpacks cause misfiring around the 4000rpm~ mark

[blind_elk]

What happens if drop the boost a bit - say 10psi?

[Trozzle]

RICH+RETARDED

Well, 12psi would be pissing on the limit for R+R, 14 would definitely cause it. Do the above and drop boost down, perhaps even further to be sure. If you don't have the same problem, you know what it was.

[forged_rb20det]

sounds like internal wastegate problem maybe needs to be replaced sounds like the actuator is sticking the same as what my car was doing

[lawler]

not rich and timming isnt retarded Ive all ready checked that.

we cant get the boost any lower than 12psi the dump pipe seems to flow to well. waste gate is not sticking. it builds upto that boost and holds it solid.

Would the coil packs cause it to bog down when it comes onto boost then take off at 3400rpms