My S4T2 rebuild finally has over 1000 miles on it so I started running it a little harder. But, it cuts out/misses really bad after 5k rpm. Its not just a miss, its like it running on 1 rotor. Compression is over 110 on all faces of both rotors. Timing looks on. The motor is all stock except for the air intake. No cats, original pipes with glass packs.

Any ideas guys.

 

do you have a fuel cut controller???

 

Check spark plugs and wires, and coils packs.

 

Double check that your timing is correct. What are you adjusting it by? Just zero'ing the CAS or actually checking with a timing light?

 

sounds like your timing is off, or you're hitting fuel cut. probably fuel cut if you have no cats.

 

Unless you have an FCD, rtek, standalone, etc... I also say it's fuel cut. Opening the intake and exhaust up will easily overwhelm the tiny s4 wastegate.

By the way, glasspacks will melt on a rotary.

 

I set the timing with a timing light. Plug wires and plugs are new.

The glass packs are holding up pretty good, really loud though.

If it is fuel cut-off, how can I fix that.

 

by getting one of these:

http://racingbeat.com/resultset.asp?PartNumber=11570

 

that's right, i quoted myself...

seriously, free flowing exhaust + stock ecu = boost spike and bucking...

get a fcd...