Nismo rear spats

[Sleepergm]

10 hours ago, MBS206 said:

No cats will keep discolouring the rear bar. Sends white paint a weird yellow stain.

Cut and polish normally gets it out, but you'll be doing that every fortnight I found.

Not sure I will have much paint left if I do that … I am going to do my mirrors shortly with some n45 primer from dr beasley then ceramic coat them. The rear has been ceramic coated already after the paint. 
 

going to put the high flow back on but just need a tuner to help me and mine is out of town for the next two months or more.  Just worried about the ignition timing. 

[Sleepergm]

1 hour ago, GTSBoy said:

Definitely needs ceramic coat and fresh wax every week.

And cats. Running with no cats is a (unt act.

Problem with putting them back on my ignition timing with the tune might get screwed up. What u think? 

[GTSBoy]

55 minutes ago, Sleepergm said:

Problem with putting them back on my ignition timing with the tune might get screwed up. What u think? 

I'd be surprised if it's a problem. A highflow cat doesn't present a massive restriction. You'd have to be tuned on the ragged edge for there to be any likelihood of something going wrong.

[joshuaho96]

14 hours ago, Sleepergm said:

Not sure I will have much paint left if I do that … I am going to do my mirrors shortly with some n45 primer from dr beasley then ceramic coat them. The rear has been ceramic coated already after the paint. 
 

going to put the high flow back on but just need a tuner to help me and mine is out of town for the next two months or more.  Just worried about the ignition timing. 

If the slightly higher internal EGR caused by a high flow cat causes detonation your tuner was way, way, way too aggressive to begin with. Timing scatter is a problem unless you go to a crank trigger, winter vs summer blend has different octane, list goes on.

[GTSBoy]

8 hours ago, joshuaho96 said:

winter vs summer blend has different octane,

I'm pretty sure that HK would only have the same blend all year 'round, but whatever.

[Sleepergm]

8 hours ago, joshuaho96 said:

If the slightly higher internal EGR caused by a high flow cat causes detonation your tuner was way, way, way too aggressive to begin with. Timing scatter is a problem unless you go to a crank trigger, winter vs summer blend has different octane, list goes on.

So you’re saying pretty safe to put back on the high flow. I guess I will lose alittle horse power which is fine. Never heard of timing scatter? My idle has been an issue running rich since I put on a custom intake with smaller pipings so not sure how it will react to the high flow cat also - would add some more back pressure to the system no? 
 

Thanks 

[GTSBoy]

22 minutes ago, Sleepergm said:

Never heard of timing scatter?

The stock Nissan CAS gets very messy at high rpm, particularly with bigger cams/springs, and most aftermarket ECUs don't do as good a job of filtering the noise as the OEM ECU somehow manages to do. So you get "scatter" in the timing signals that can be really destructive to the ECU's knowledge of engine position. And so you can get spark firing many degrees early, leading to catastrophic detonation events.

[Sleepergm]

10 minutes ago, GTSBoy said:

The stock Nissan CAS gets very messy at high rpm, particularly with bigger cams/springs, and most aftermarket ECUs don't do as good a job of filtering the noise as the OEM ECU somehow manages to do. So you get "scatter" in the timing signals that can be really destructive to the ECU's knowledge of engine position. And so you can get spark firing many degrees early, leading to catastrophic detonation events.

I’m running links ecu and an upgraded crank sensor. So I guess I have less chance of this. 

[GTSBoy]

29 minutes ago, Sleepergm said:

I’m running links ecu and an upgraded crank sensor. So I guess I have less chance of this.

Probably. But keep in mind that all Joshua was saying that because of things like timing scatter, and many other related and unrelated things, tuning too aggressively should be avoided. Hence why both he and I said that fitting the cat shouldn't cause you to suddenly fall into the danger zone.

[Sleepergm]

1 minute ago, GTSBoy said:

Probably. But keep in mind that all Joshua was saying that because of things like timing scatter, and many other related and unrelated things, tuning too aggressively should be avoided. Hence why both he and I said that fitting the cat shouldn't cause you to suddenly fall into the danger zone.

Yeah its tuned relatively conservatively being dynoed at 525hp with every bolt on and top end of the motor built wtih HKS vcam and springs etc.