I'm pretty sure both coupe and sedan have the exact same engine with the exact same compression ratio which in turn means both cars require the exact same fuel.

Thanks buddy, you have answered me with a great deal of information yet again. Now to just clear things up even further, so 94 octane fuel is too high of an octane and may actually reduce power to my untuned '04 G35??

Also the Osirus tune CAN increase compression ratio because our engines have electronically controlled cam phasing meaning my car can be tuned to run the 94 octane??

Thanks again

 

94 octane will not hurt hp output. If anything, it allows your motor to make more power. A higher octane does not necessarily make more power by itself even though you will fell a difference, but that's because your ECU is making adjustments by itself. All you really need to know is that higher octanes help prevent detonation better so you can make more power. This basically allows you to squeeze more fuel into the cylinders, and more gas = more power. For example, we only have 91 out here, but a map for 100 octane gave me over 10 hp to the wheels (something like 18hp... I don't quite remember anymore). The reason for this is because the 100 octane allowed us to tune my car more aggressively than 91 octane would allow.

There is a way where a high octane fuel can become harmful to your motor, but your motor will still be able to put down much more power with it, and you will never have to worry about that problem at any commercial pump or gas station... At least not until they start carrying 112 ethanol.

 

Will 2003 sedan valve covers (non rev up i assume) fit my 2005 6mt coupe (revup)

 

I have this rattle, and found this video on youtube that exactly sounds like the rattle that I have


It comes from the back of the car, and usually occured when going on a bumpy road, but now it's rattling more frequently. What can I do about it? Is it the axis? Something else? It's becoming increasingly more annoying.

Please help

 

^ Well I figured if my untuned engine can't compress the higher octane enough then I'm just drowning it with the harder to ignite high octane fuel.

I'm not sure if I misread your reply but you said that the ECU makes adjustments by itself and adapt to the 94 octane? I thought it just prevents pinging in the engine not increase compression ratio....

^ That's a new gen G35 you're in the wrong part of the forum.

(I can't believe you have the same name as me lol.....)

 

So I have a crawford intake plenum. It came on my car when I bought it. So I read crawfords site and it says the slanted stock plenum restricted airflow to the front cylinders. The crawford plenum is designed to have equal airflow distributed to all the cylinders.

Ok, so I ordered the isothermal motordyne 5/16. It should be here Monday. My question is do you think the spacer will be a waste? I'm assuming the purpose of the spacer is to take care of the restricted airflow problem. I know that it has other benefits too with the cooling of the plenum. So let me know what you think.

I don't know if I already have an mrev2, I figure id find out once I put the spacer on. If I didn't have it, id buy it.

 

^Buying the spacer probably was a waste in your case, or you could just not use the Crawford.

This is what the MREV2 looks like: https://g35driver.com/forums/2540400-post16.html

 

I didnt realize that I posted it in here, very weird. And lol, nice choice of name haha

 

Coupe or sedan? If you have a coupe, there is a metal piece right next to the muffler that is only there for aerodynamics that tends to get loose and rattle a lot.

There is an increase in output from simply switching from 91 to 100. You can gain much more with a tune, but there are definitely a few extra horses there, and the G35's intelligent ECU is the only explanation.

 

That could be! Could you specify where/what metal piece it is? And what can I do about it?

Thanks!!

 

any Gs you know of that went VIP? links?

 

It's right before the muffler. If you get down behind the cat, it's a metal piece directly on the other side of the muffler. It has a triangular shape from the side, and it looks almost like another muffler-like canister from below. You can either tighten it or remove it altogether.

 

Well im a new driver but have a noob question but want to make sure of this problem

Well yesterday I had my key in the ignition for 10 seconds and my battery didnt die but would not turn over to start

All day yesterday it was fine than a half hour ago 24 hours after the problem never expiernce e this before I go right into my car after work work and put my key into ignition wouldn't turn on.

Is my battery going dead I think so please help because if so I need to buy a new one tomorrow

 

Made a reply by accident

 

Anyone know a good site for deals on tpms sensors I also need to get new tires maybe throw some rims on it to.

I want to drop about $1500