I'm e-tuning, so I'm not quite sure of what to expect as far as getting numbers back. I'll ask Sebastian.

 

So let me get this straight... CB + Intake + tune = HFC + CB + Intake + tune

Meanwhile... CB + Intake (no tune) < HFC + CB + Intake (no tune)

Is that what your saying, ShuuraRG? I think I can believe that. It still sounds right that HFC (or TP) is the best bolt-on power mod you can do, but if I'm following your proposal, that's purely as an un-tuned bolt-on.

 

Sebastian is basically a god when it comes to tuning VQ's so I'd believe his info lol I don't know where everyone on here got this "TP's are the best power mod" attitude but I can assure you they're not. If you took a power to dollar ratio and compared it to more expensive mods, then I guess that makes sense. But as for our sedans. The cats are not the choke point, our CBE is. So starting with test pipes doesn't make sense. Pairing TP's and a good CBE exhaust will give you bigger gains when compared to just a CBE. But if you take mod for mod, and one mod only, you will make more power from a CBE. That's why I was so confused when people on here were expecting 0-5 hp gain from a CBE upgrade!

 

Gregor, it's hard to say this with confidence, because anecdotal evidence is only a guideline at best... but that runs counter-intuitive to the majority of opinions on this forum. Which is, if all you do is cats or a CBE, un-tuned, then the cats are the stronger mod.



Purely academic for most of us, I think, since after you do one the other isn't far behind.

 

This is not an opinion. It is a fact. The Dyno does not lie! lol I say this with 100% confidence. The stock g37 sedan cat back exhaust is more restrictive than the stock cats. TP's will not produce a larger gain over a cat back exhaust.

 

From my conversations with Sebastian, not exactly. HFC's will net you a few HP than without, but not as much as the cost of HFC's would lead you to believe. Here's a brief email exchange between he and I.

 

Look what I got . Was just gathering dust if my friends garage. Randomly gave it to me since he didn't need it. Now my G gets a brand new mishimoto oil catch can.

 

You have some awesome friends..

 

I know my Resonated TPs gave me much more kick in the butt dyno than my y-back, intake, and new y pipe. so
Hopefully some tune in the near future just to see if I need to have my butt re-calibrated

 

But it's not like you installed your TP with the OEM exhaust, then put the cats back on and installed the aftermarket catback.

Exactly to your point here... I installed the RHFC's first, and the FI catback a full year later. My butt-dyno impressions were significantly in favor of the high-flow cats over the added changes after the catback, although that was well-received, too. And all this still un-tuned.

IDK, man. Exhaust mods offer power gains at the cost of added noise, and the better power is always the mod closer to the engine. Maybe because the G's OEM headers are efficient enough that everything else is an un-tuned balancing act.

I don't want to get into it for a number of reasons, mostly because I'm a garage queen computer jockey, and not an engineer. But also because it's kind of a personal moot point, so this is just curiosity for me. But mostly because I don't want to argue the third-party integrity of a VQ God. I suppose if someone is a VQ God, then you just avert your gaze and agree.

 

Okay, I'm going to be THAT guy, again, and remind y'all the butt dynos are big fat liars. You made a change, you expect different performance, and you find it. Real or not...

Time slips and dyno charts don't lie.

 

Hey for my 6MT folks who upgraded their front end links when you installed your sways, what type of links did you end up going with? I've come across nothing other than SPL for RWD.

The reason for my inquiry is because I upgraded my front links to the SPL's and even though I've lubricated the bearings as recommended I'm still getting squeaking noises from them. I've 100% confirmed with my two mechanics that is where the noise is coming from.

If you do have the SPL's and are coming coming across this issue, what do you use for lubrication? If you have a different type of end link, could you please forward this info as well? I confirmed with Whiteline that they do not carry these for RWD.

Thanks in advance.

 

I assume this was referring to me since I used the "VQ God" term the other day... Whether it was or not doesn't matter.

Let me ask you guys this. When you go to the Doctor and they diagnose you with something, do you argue your point and then go google your symptoms to try and solve your issue yourself? Lol no. Didn't think so. So yes. When someone TUNES these cars for a living, and actually knows what in the hell they're talking about when it comes to mods... You bet your *** I'm going to believe them. The but Dyno is pure bull****. You guys speak of "un-tuned" power and tuned power. What you do not understand is that's our Ecu's are adaptive to a certain point. Our Ecu's have a target a/f ratio that they try and stick too. Our sedans seem to be at 11.5 which is rich as hell. So say you install some kind of aftermarket exhaust component that allows you to move more air in and out of the engine. Your computer will pick up on this and increase the duty cycle of the injectors to account for the increased air flow maintaining the target mixture. This results in a larger amount of air/fuel mixture in your combustion chamber which results in a stronger explosion making more power. Now, the real question is, how can you increase flow and where should you start? Would it be the catalyst? Would it be the intakes? Would it be the cat back? Which one is the most restrictive? Well that would be your dual 1.6 inch catback. What's the point of removing the cats and then keeping such a small tubing diameter throughout the rest of the car. Yes you'll gain power but then the exhaust will restrict your test pipes... Oh, and dont forget your y-pipe that's even worse...it's common sense to start with the biggest problem. Mod for mod can go round and round since different brands yield different results as well. Just change it all and get it tuned if you want to want to maximize your performance while staying NA. You guys just expect the TP's to net you more gains because that's what you've been told or heard. When it comes to the Z's that have free flowing exhausts, test pipes are a great addition. But not to our sedans. Because our cat back exhaust is where we lose power, plain and simple.

 

Also, I learned a lot while working with the engineering and quality control department at cataler of North America. Which makes the catalysts for Toyota, GM, and Subaru. A catalyst is nothing more than a clay type honeycomb structure that creates a chemical reaction once it reaches a certain temp. THats why they're close to the motor. That's where it gets the hottest. Notice during a cold start the exhaust fumes are abnormally strong and smell like you don't even have cats. Well that's because the catalyst hasn't reached the necessary temp to begin its chemical reaction. The whole point is to make the catalyst efficient to where it's not very restrictive while still completing the chemical reaction. You can extend the catalyst and use a less restrictive honey comb that will flow well but still do its job and omit the unwanted elements. So to assume that a catalyst is the most restrictive exhaust component just because it's a catalyst is nothing more than a uneducated guess. That's all I have to say about the whole test pipe vs cat back argument. It's been Dyno proven as well. Numbers don't lie. Change it all and get your air/fuel mixture right with a good tune. Staying stock is for quitters.

 

Tl;dr?

I think you'd probably be amazed...