Loss Of Power...?

[Zadz]

Hello All,

Iv have experience some issues and thought may aswell as if anyone has some ideas for me to check.

Alrighty, I bought a BA MKII xr6t about 10months ago now it has been modified alittle (see below list) and all has been good.

I was bitten by the modify bug a few years ago, when I had my r34 skyline, spent a pile of cash on that. All was good, but had a mid life crisis (at 22 lol) and sold it off and bought a house, years gone by and I couldnt sastify my car hobbie urges, so bought the xr6t and all is good.

Since I bought the car till now iv had a wedding and various other busy life things, so havent had much time to play with it yet. A mate of mine heard through his work a dyno day, so we went down to check her out, put her on the dyno and expecting 400ish HP (previous owner supplied old dyno sheets when it was tuned showing 330rwkw), the dyno only shown 300rwhp.

As you could imagine was very heart breaking.

Only thing I have changed on the car since I bought it has been install of a BOV (didnt have one preivously) and servicing.

But in fitting the BOV I had to make shift the piping etc to fitment, and after fitting the passenger headlight again it has compressed the intercooler piping ( I need to get some more pipe and silicon and fix it up properly, was taking shortcuts)

The piping under the headlght reduces the diameter to half the area in oval shape. This cant be good with power restrition.

So would this be the main cause of power loss?? It has been 40-50k kms added to the clock since the intial tune and dyno sheet. Would this have lowered the power over time. Something I havernt checked that may need maitenance?

Running out of ideas, I thought it was a collasped CAT so one weekend I took the cat off and checked, there is no problem there.

Any suggestions would be great.

Im in Perth.

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Known Mods:

Full exhaust dump and cat (3-3.5inch)

Nizpro Plenum

Nizpro Intercooler (reveresed end tanks, hotside bottom - cool side top)

Battery relocation for Pod filter in its place.

Fiberglass surround pod filter.

Nizpro valve springs

6psi wastegate actuator

injectors changed and fuel pump (not sure on size)

Custom dyno tune (old Xcal1 used) so retune will be expensive.

Running 1BAR boost (14.7-15)

(Nizpro Stage 2 kit,)

Dyno Tune by APE (55k km odo)

337kw @ 5000rpm

930NM @ 4000rpm

Car currently at 110k kms odo.

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[MX Dave]

Farout mate. My BA made almost 300hp basically stock. Do you have a boost gauge? Is it possible it was reflashed with the stock tune before you bought it?

[Zadz]

I know!! its really annoying. I have the Capa Tune box, it came with the car, and I ran it over again on the install, so im assuming it has the performance tune on, it has 1/2/3/4 tunes listed, on the card that came with it it says which tune is which.

I havern't got a boost gauge installed yet, my new cobalt actually has just came in the mail, will fit it once my xcite gauge holders turns up. but I have plugged in a mates boost gauge to check, was reading 1bar while I run up and down the road.(wasnt a PSI gauge, BAR only)

its getting frustrating

[Barra]

  On 06/01/2012 at 9:33 AM, Zadz said:

Most jap cars using a AFM will shot flames on gear change with a Atmo BOV installed, my old r34 did this untill a aftermarket ecu and retune was done.

I pulled my cat off one day to check if its collasped, it wasn't, but since I came that far I punched it out. other then smell, can't tell difference, as in power increase im having other problems atm to know.

This

  On 06/01/2012 at 9:45 AM, Barra said:

Hey mate saw your other posts and are some of your issues after bashing the cat? Your tune will not be set up for this, unless it was hollow to begin with, might make the car over boost. Found this out with my old s4 rx7, before I understanded the consiquences.

And this.

[Zadz]

had power issues before I played with the cat, I went searching through the cat thinking it could of been one of the problems. Before and after cat punching, car drivers the same,

if anything punching the cat has increased spool times etc.

[Ralph Wiggum]

still having problems mate?

[Ciaran]

Not only is the outside of your car almost a Twin to Lukes, but your engine bay looks almost the same too rofl.