Fast Intentions exhaust is here!

ProfessorDave

Hey Pelican,
While I don't have HFCs, my understanding is that the hiss is inevitable. I'll let someone more technically savvy explain it better.

In terms of the oil temp, I've been in the 220 range before. Limp mode kicks in at around 280 I think? I don't think 240 is anything to be concerned about, but again I'm not up on the details of the oil temp thing.

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Pelican170

yea, the hiss isnt a problem, i actually think its kinda cool lol, just wondering what it is exactly. And the oil temps I was just curious about because i havent seen them that high until i put the bolt ons on... Thanks for the help though...

wstar

I've never fully understood the technical reason for the hiss, but all our cars seem to have it HFCs at least. It happens on decel at a certain RPM range. Personally I kind of like the sound, but I'm wondering if it will change or go away with LTHs. I'll find out soon

Re: oil temps, keep in mind the ambient temp is warming up everywhere as we enter summer, and this has a huge impact on your oil temps, it's likely the reason you're seeing a rise. I'd say as long as you're not regularly staying up past 240 (e.g. 260+) you don't really have anything to worry about. A good oil cooler is the solution if you're tracking the car, or driving it hard in hot climate. The exhaust setup isn't really going to change the oil temps situation much, except that maybe you're more prone to pushing the car harder now that you enjoy the exhaust note more.

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Pelican170

I understand the fact that its getting warmer out, but last year even in the hot humid summer, it never got past 220 and now when i was driving mildly on the highway, it was sitting at 240... thats strange and never happened until i got the bolt on's on...

XwChriswX

First point - The hiss comes from having an X-Pipe. Has nothing to do with Stock cats or HFCs or test pipes. If I recall correctly it is from the equalization of backpressure between the two sides of the system... Tony will have to come in and 100% answer that one. But the only way to defeat the hiss is to have either a complete dual system or have an H pipe as with the Nismo exhaust.

Second Point - The overheating issue... When you installed your CBE/HFCs, did YOU do it or did you take it to a shop and have them do it? In either instance, did you get it tuned afterwards? If no tune did you at least pull off the negative battery terminal for a few minutes to reset your ECU? Adding these breathing mods allows your engine to flow more air = more power. However comma if you haven't reset your ECU to adapt to this, it might still be running the same cooling maps as it would for stock. Which now that you're getting more power your block is heating up faster and the ECU isn't compensating for this. If you haven't done the battery reset, I would suggest to try that, remove the NEGATIVE terminal for about 5 minutes. Then return it and crank. Let it sit and idle for about 10-15 minutes. Then take it around the block a few times without getting on it. And let your ECU learn how your engine reacts with the new mods. Maybe this will help it adapt better and keeps your temps back down where they were. Or it could just be due to the weather getting warmer/more humid...

LTH's will not effect the sound at all. It's still there loud and proud.

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Bonnie - Stage 2, Audio build coming this fall!
R.I.P. Abby 3/29/10 - 3/30/14

Pelican170

Hey thanks for you information. I did bring it to a shop to have it installed and I did not get a tune. I was under the impression that with just bolt on applications, you wouldnt have to worry about the ECU and that it would adjust itself with some miles. If i dont see a change in the temp after driving it a bit more, I will do as you have suggested and remove the negative battery terminal as instructed. Thanks again for you advice...

Ron

Hmmm I know of someone that has HFCs with a Y-Pipe and the hiss there.

XwChriswX

A tune isn't completely necessary unless you do full bolt-ons, but it's still good practice to do the battery reset anytime you change any performance mod. The ECU would eventually adapt to the new things over a given amount of time, but instead of the adaptation we want it to have, it would think something is wrong and cut back power. This way you're starting fresh and it takes what it's reading from the engine as 'normal'.

Do they have the stock exhaust still?

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Bonnie - Stage 2, Audio build coming this fall!
R.I.P. Abby 3/29/10 - 3/30/14