Jump to content
SAU Community

Recommended Posts

Hey all,

Ok I have a 1991 R32 GTR. It has detonated since i picked it up in UK. It is unmodified except for a decat pipe. It has detonation. Looking at the pistons, 4 is pitted and 6 is mildly pitted. When I changed to denso plugs 4th cylinder took a tip off.

Important info:

  • It runs factory boost with restrictor.
  • Brand new coil packs (standard)
  • A/F ratio about 11/1 full boost (measured with innovate wideband LC-1.
  • Ignition timing set to 20o BTDC using HT lead between coil pack and plug on first cylinder
  • New cambelt
  • Completely unmodified engine
  • Cleaned and flowed fuel injectors
  • Fuel pressure tested and Ok.
  • Manifold checked and not leaking
  • boost around 6-7 psi.
  • stock ecu, unchipped.
  • new ignition amp (standard)
  • Fuelled on super unleaded.

Any ideas???

Link to comment
https://www.sau.com.au/forums/topic/368579-det-problem-getting-desperate/
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • From when I was looking at getting the 86 engineered for the turbo, the joint said to put in a few euro 5 or 6 cats, then tune the car on a nice clean E85 tune When I was looking at a turbo for the MX5, it was basically the same thing, a couple of cats and a nice clean tune Although, it will depend on the year of the Jeep IRT emmisions standards required, and what mods are done, especially if it has a newer engine installed that requires a higher Euro
    • Yeah - but it's not actually that easy. There are limits for HC, CO, NOx and particulates. Particulates shouldn't be a concern in any petrol engine unless trying to comply to the very latest Euro standard. But getting a tune right so that all the others stay within limits AT THE SAME TIME is not a trivial exercise. You couldn't possibly get it right by just guessing at the tuner's dyno, unless he had a 4 gas analyser up the pipe, which is not often the case these days. It used to be. Every decent shop that did "tune ups" (as opposed to tuning) would have a 4 gas analsyer. Perhaps there's still quite a few of them around these days. But most "tuners" are only watching O2 and power readings.
    • Slight segway but the most expensive part of the whole thing which I would have thought would only be required for an engine size/type swap, not a VIV test, is emissions testing.  That's when you get into the big bucks.  I can't remember the exact price now but I got quotes for the GT-R based on swapping to RB30 (not that anyone bothers doing it legally anymore...) and it was around $4500 just for that alone.  The guy that does them manipulates the tune on the vehicle to make sure it passes.  The cheaper option is to book into Kangan Batman Tafe (I think that's where it was) and hire their tester.  Allegedly you're not allowed in there with the car though so not in a position to tweak anything to make sure the vehicle passes.  I'm sure in this day and age of ultra tuneable ECU's you could get the tuner to program a special efficiency (clean) tune that emits the lowest amount of particulates possible that would pass the test.  It might only make 50kW's but as long as it passed who cares!
    • I'm sure he has left signs, or, he is looking down, laughing That's my cunning plan for when I leave, lots of half finished projects, with no rhyme or reason of where I was actually up to, just to keep everyone on their toes
    • Does that price include the rack time to straighten the frame and body and replacement of parts and paint, as well as the noise and emmisions testing  The last engineering certificate I had done, albeit about 15 years ago, was around $1000 for a few inspections and the certificate 
×
×
  • Create New...