What hardware was I supposed to get with these? Mine was loose in the box and I think I missing some bolts...

 

Did you buy those from us? http://www.performancenissanparts.co...roducts_id=188
If so we include a hardware kit and will send you one right out. They do not come with any hardware from the RT, but due to customer demand we now do.

 

We include hardware.

Included is 4 nuts and bolts per Cat (total 8) 2 washers for each one and 4 shims. You will re-use your gaskets and one of the bolts.

Let us know if you have any other questions.

 

Wow Thanks for the quick response!!!!

I did get 4 bolts per cat with nuts and washers + 4 shims.

I wasn't sure if there were supposed to be 5 bolts per cat, there being 5 holes

Oopps almost forgot...What are the shims for?

I did order from you guys. I think you have some of the most prompt service I've delt with!

Thanks everyone at Performance Nissan!!

 

When you are under the car, the shims go between the rear cross-brace incase your exhaust hangs low enough to hit it and rub. We recomend installing these any way.

Here are pictures of where they go. It will look more familar when you are under the car.

 

Aahhhh....Great, so it helps move the brace out of the way.

Nice Touch

 

Tadashi at TechnoSquare says the cars with the RT hi-flow cats run lean. He took out one of my spark plugs and the top of the threads was black. It was running very lean. You should watch out for that. The TS ECU flash solves that problem.

 

Crap! I think I'm running lean cause I have the plenum and straight pipes.

 

If you are reading the A/F ratio from behind the cats it is not accurate. It must be taken from the cylinders.

Here is my dyno graph with A/F and High Flow cats and no intake.

Intake mods will cause you to run lean. Cats will not effect how lean you run since they are placed after combustion occurs. High flow cats lets the exhaust gasses get out of your car faster.

Plenum / Intake mods cause lean conditions

 

The only way I could see the high-flow cats causing problems is if the ECU does some sort of long term monitoring of the O2 sensors. It's possible that the ECU could come to the erroneous conclusion that too much fuel is being supplied and therefore cut fuel.

I've read that ECU's can do some weird stuff like ossilate back and forth between rich/lean at part throttle to monitor the health of the cats as well as clean them.

--
Jeff

 

For now I am excited to get these cats in. Hopefully tomorrow before the feasting begins and I can't move

Regardless, I am interested in a CAM / ECU combo. Hopefully we will see something soon that gives gains that will justify the cam install price. Maybe JWT

 

If the "exhaust gasses get out of your car faster", doesn't that mean that more air/oxygen is drawn into the combustion chamber during the intake cycle? And if there's more air being drawn in within the same period of time, doesn't the air/fuel mixture become leaner?

 

dont like

 

Exhaust gasses are particulates; when more of the particulates are allowed to escape, more air molecules are allowed to enter, yes?

 

 

"just alows more to get out so the intake can pull more in..."


This is precisely my point. Since more exhaust gases are allowed to escape, then more air can enter the combustion chamber. More air for the same amount of fuel equals leaner mixture

 

From everything I have seen so far...

Cars that run lean have Intake and Camshafts' modded.

Anything alowing more air into the car then the stock ecu can calculate for. thast why the TS ECU comes in handy with intake modded cars.

I can not tell you exactly what the cat's do... but i can tell you that they definatly let exhaust gasses exit the engine faster with the least amount of resistance.

 

"Cats will not effect how lean you run since they are placed after combustion occurs."


Your statement above is contrary to my understanding of the how a combustion engine works. Cats do affect the air/fuel mixture.
This was the extent of my issue with your comment. That's all.

 

I understand that yes,

but not as much as intakes which draw more air into the plenum / cylinders.

until you go up to cams your not going to run lean to the point of causing harm.

as i know it atleast

 

"Cats will not effect how lean you run since they are placed after combustion occurs."




Can you just admit that this statement is principally incorrect? It is, you know. Sorry.