nub Posted November 30, 2016 Share Posted November 30, 2016 Hi guys I've been researching what kinda setup I'd have on a 370z. Because for good power I'd need the stillen intake, some brand of HFCs and an after market exhaust. Is there anything else? I might one day try decat pipes too if the gains were like 20bhp over the HFC, but I'm guessing it's far less. Horsham developments told me the highest figure they made on a 370z with decat/test pipes, a cat back and intake is 357bhp. Is this true, or has anyone achieved better than this ? Secondly, after watching many YouTube videos it seems that with either HFCs or an aftermarket cat back alone, it improves the sound and volume dramatically yet still remains refined. But add both of them together and it becomes too loud, subjectively speaking. But most would agree it's a bit too loud and approach WOT and you'll really let the whole street know about it. It was the same @*!# with my EP3 & FN2, the aftermarket cat backs are designed with consideration that most owners will not use HFCs or worse, a decat. They may actually be the same in volume if the HFCs do not have any resonator or deadening, I do not know. So my plan was that if/when I got HFCs I would go to a custom place and add another two smaller silencers in the cat back system, they wouldnt be huge but enough to reduce the volume/decibels by 10-30%. At least 20% to be worthwhile it's quite possible to do so on a stillen car back as they appear to have the space. Other systems may not, without having the whole section redesigned. This should get it to the levels of a system with only either HFCs or a CBE, but not as overwhelming as both. And I know different CBEs vary slightly. The next issue I have is, ARK GRIP and HKS power have opted for like a second silencer where the piping is blocked off. Two of them. I guess the idea is that the gas/sound flows into there and out again, some of it being reduced before coming out of the exit pipe. As I understand, this is considered to be the best sounding exhaust, and the disruption in flow and exhaust pulses may enhance the sound, much like unequal length headers create a nice burble. HKS also sounds prettt nice and it's the exact same principle. But surely this design must cause back pressure? on K20 systems any back pressure results in loss of BHP, if only 2-5 BHP and at the higher rpm. Is the regular straight through design of the stillen not proven to be superior? I don't pretend to know about this engine but that's how it works on the K20 so it made me wonder. Has anyone done any comparisons? There may be other factors involved too such as the pipe diameter, routing & quality of bends, welds etc and it could even be that the ARK GRIP is simply slightly louder and people assume it sounds better because of this. P.s I've just realised they refer to it as an X-flow or dual chamber so I'm going to research what they claim this does ! Quote Link to comment Share on other sites More sharing options...
Jetpilot Posted November 30, 2016 Share Posted November 30, 2016 (edited) They arent silcencers as such, they are helmhotz resonators, designed to reduce certain unwanted frequencies, back pressure is immaterial, its not forced induction where removal of back pressure is important for hp gains, which leads nicely onto and as mentioned before, forget bhp talk, its just pub banter, if 357hp is the highest figure Horsham have achieved why would you question if its true? Even if some had achieved 367 or 373, put all three side by side, the difference would be barely noticeable, so why does it matter if its 357, 367 of whatever? Sorry if thats not what you want to hear, but if your chasing dyno figures, a na car is not for you. I also wouldnt be cutting up over a grands worth of exhaust, if you want custom sound, just go custom to start and after trying a few exhausts first hand, youtube really doesnt give much more than a guide, they sound very different in the flesh than through speakers, pop to a meet for an accurate appreciation. Edited November 30, 2016 by Jetpilot 2 Quote Link to comment Share on other sites More sharing options...
Tarmac@TarmacSportz Posted November 30, 2016 Share Posted November 30, 2016 You can't beat the sound of the Ark Grip in my opinion, i've had them on a few cars now. We have the Berk Decats and Stillen intakes in stock and can get the Ark in for next week. Quote Link to comment Share on other sites More sharing options...
nub Posted November 30, 2016 Author Share Posted November 30, 2016 Well that's interesting that they're resonators but these would cause back pressure on a 2.0l NA. Pub figures or not, I do like to know what BHP each mod is making and if I had that care free attitude to each mod on my car then gains would be entirely irrelevant! Of course there is a difference between 357bhp and 373bhp, it's not a great deal and you'd struggle to notice it but it is a significant difference. I figured someone might know the performance difference of the two exhausts and what effect that dual chamber design had. On type R forums it's pretty straight forward and through dyno evidence we've learned which mods perform better etc, even if the difference is minor. A combination of superior mods can result in a more significant gain. I think I'd try one of the resonated decats if I wanted all out power. An ARK would be great but I cannot see myself buying one brand new, well not just yet Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Payco Posted November 30, 2016 Share Posted November 30, 2016 (edited) Hi. Not sure where you are based in Sussex but I have the ARK Dual Grip on my 350z so you are welcome to come along and view and listen. Just PM me. Edited November 30, 2016 by Payco Quote Link to comment Share on other sites More sharing options...
Jetpilot Posted November 30, 2016 Share Posted November 30, 2016 Of course there is a difference between 357bhp and 373bhp, it's not a great deal and you'd struggle to notice it but it is a significant difference. On paper, yes, in performance, no, so why does it matter? except for pub banter, its certainly not significant. Its a 1500kg plus car, I have driven an upreved 350z and non upreved, so maybe 20hp if you take factory numbers as gospel, was the upreved any faster, no, did it feel better, yes, but i put that down to having the throttle restrictions removed, i have also been on track with both, i couldnt overtake the upreved, he couldnt overtake me, that is not significant. Just trying to say from experience of ownership, if your chasing figures, you will be disappointed, if you want a great rwd sports coupe, you will love it. Quote Link to comment Share on other sites More sharing options...
nub Posted November 30, 2016 Author Share Posted November 30, 2016 I like to know that my performance is maximised and so my money is well spent on mods that provide the best gains possible. If 360bhp is the most I could get on a 370z then so be it, but if 370 were possible then I'd be happier 'chasing' that figure, whether it's significant or not. We don't utilise the power all the time when driving but just knowing what it's capable of is half the fun. And to me, 20bhp/lbft would certainly be worthwhile and perhaps just about noticable. If I was only interested in performance then I'd stick with my civic, which is a fair bit quicker already than a standard 370z, or even a modded one. But if I'm to change to a 370z then I'd want to extract as much power as possible, which is what I'm trying to determine at the moment. But I'm guessing nobody has done back to back comparisons of the cat backs, so I'll just have to make a guess. There's probably not more than 5BHP difference between them anyway Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Dracostan Posted November 30, 2016 Share Posted November 30, 2016 (edited) I have just been in a similar situation to you - go for an Ark Grip, AAM 3" Competition or cat-back custom. I decided on a custom, as in talking with the owner of the fabrication garage, I could get the combined look of both the pre-made exhausts that I wanted for SIGNIFICANTLY less money - almost £400 less than the Ark and £800 less than the AAM(!) and get the right volume level for my preference. In fact, I am booked in to get some center silencer cans as I found the first configuration, while sounding awesome and the right tone, it was just too loud - and the fabrication garage is doing this for free .... well, as part of the original system costs. The benefit of a custom is exactly this: you can choose the volume and tone of the exhaust note and get details of personal preference just right (like can size, hang angles, exit tip finishes, etc), in combination with other exhaust components like HFC's or decats, without the up-front costs of a pre-fab - then possibly having to pay extra to chop into it, or finding a whole other system to get that 'just right' exhaust note you are looking for. If you do choose to go custom, I'd recommend the Longlife franchise - they are fabrication specialists and have workshops in Sussex and Surrey - as well as several members here (including me) having had systems from them up and down the country and being very satisfied with the quality of work and results. Draco Edited November 30, 2016 by Dracostan Quote Link to comment Share on other sites More sharing options...
GMballistic Posted November 30, 2016 Share Posted November 30, 2016 On paper, yes, in performance, no, so why does it matter? except for pub banter, its certainly not significant. ...Just trying to say from experience of ownership, if your chasing figures, you will be disappointed, if you want a great rwd sports coupe, you will love it. Totally agree. Plus you have to remember nub that 350Bhp on one companies dyno maybe 325Bhp on another companies dyno, ....or my car with 300Bhp tested on a company dyno one day maybe 315Bhp on the same dyno the very next day (so many variables). Also as proven countless times on here just because one persons Zed made X amount of Bhp with certain mods doesn't mean that another Zed albeit of the same year/age/mileage etc will make the same Bhp figure with the exact same mods. For example my 2003 350Z with a Vortech supercharger set up made 436Bhp@fly but similar modded Zeds have made plus or minus of 20-30Bhp. Just take a look at the "Official list of UK FI Zeds" here: http://www.350z-uk.com/topic/66265-official-list-of-uk-fi-zeds/page__st__140 Or the "Dyno Results Info Thread" here to see what I mean: http://www.350z-uk.com/topic/23450-dyno-results-info-thread/ I totally get though why you're trying to research this as best you can for when/if you start modding a 370Z but certain things like the exhaust systems are governed a lot on here more by what it looks like, how much it costs and the sound it makes more than how much extra Bhp/torque it will give you as the difference in that respect on an N/a engine is so small it really won't make a lot of difference on the road/track. Hence why JP mentions it's only good for "pub figures". Better tyres, brakes, suspension components and some professional driver training will easily make you a faster driver than a few extra Bhp from one exhaust system over another. All imho. Quote Link to comment Share on other sites More sharing options...
EvansJD2112 Posted November 30, 2016 Share Posted November 30, 2016 Ark Grip with Cobra HFCs Quote Link to comment Share on other sites More sharing options...
nub Posted November 30, 2016 Author Share Posted November 30, 2016 Oh come on I'm not new to the modding scene, I did supercharge my FN2 I know all this anyway but I was still interested in the gains, but it seems not any care about it. It is important though, there can be a fair bit if difference between the best and worst induction kit (for example). Different dyno s, different engines yes. I know. Even different ambient temp on the day. Yet still on CTRO we've managed to establish which are the best performing mods! You can pretend you're not so bothered but then you would be if it turned out the ARK GRIP consistently made 10bhp less than its rivals! Dyno figures sell a lot of products. Anyway if u wanted all out performance I'd have stuck with the FN2. But I like the other characteristics of the 370, namely the engine and sound of it. Also the looks. Plus I'm looking forward to doing some 1st gear launching which I can't do on my FN2. I'd probably go with one of the resonated HFCs for now and swap it with resonated decat when I go for remapping, depending on how restrictive 2x 200 cell cats turn out to be. I guess there's no point asking you guys this question but on a K20 even one sports cat would probably lose 10 BHP over a decat. I'd love to find out more about the dual X flow chambers, it may be legit, probably is but it sounds a bit like a gimmick. I've had 3 different custom cat backs. First one with longlife and then two from solid fabrications. I did consider a whole new system but it would be much cheaper to get a stillen modified slightly. It would be done in a very professional way, the fact is, I think with any HFC or decat it would just be too loud. But I've not heard the resonated ones so I may be wrong. All I can do is search you tube. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Jetpilot Posted December 1, 2016 Share Posted December 1, 2016 As an example , the best induction for the 350z is the std air box with a decent panel filter, open filter induction kits actually loose power, but people still fit them, so I guess dyno figures are not important on here and the x pipe is just do with the note achieved by mixing the pulses from each bank of the v configuration. Its a lazy big capacity 3.7 ltr v6, not a high revving small capacity 4 pot that probably responds better to breathing mods, your asking questions and not liking the answers, no one is lying mate, its just the way it is. Quote Link to comment Share on other sites More sharing options...
nub Posted December 1, 2016 Author Share Posted December 1, 2016 Jet pilot can we not just agree to disagree? The stillen intake & cat back are claiming 10-20bhp each and that is relevant to me, even if you don't care what they make. The X note sounds interesting and I wish there was more info to back up the claims. If everyone says it's the best sounding exhaust then it probably is, and that's the kind of definitive info I was looking for. I do think of the 370z. An make over 30-40bhp with mods and remap then that's certainly worthwhile for me Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
coldel Posted December 1, 2016 Share Posted December 1, 2016 I put Berks HFC Stillen intake milltek exhaust motordyne plenum spacer and a remap on my 350z which based on manufacturer individual claims of 10-20bhp each would have got me a lot more bhp than I actually ended up with. In any case I generally ignore max bhp figure that's not a measure of performance increase at all it's the increase in area under the entire curve that actually makes a difference to on road performance. Sent from my iPhone using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
sipar69 Posted December 1, 2016 Share Posted December 1, 2016 Re the original post - I wouldn't agree that an aftermarket CBE and HFCs are too loud. Mine is certainly loud on cold start but once it settles down it's fine and the same goes for normal driving - perfectly civilised if you drive normally, but plenty of volume available if you want it. Quote Link to comment Share on other sites More sharing options...
nub Posted December 1, 2016 Author Share Posted December 1, 2016 Got any driveby vids? The ones I've seen are so loud you can hear them a mile off and in a built up area they reflect off everything and so loud you'd gain the attention of pretty much every pedestrian just by going above 4000 let's say. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
SunnyNags Posted December 1, 2016 Share Posted December 1, 2016 I've got a full motordyne setup. ART pipes and full shockwave system. The craftsmanship is excellent but its a premium compared to other setups. Its rediculousily loud and aggressive but what I wanted. Try out a listen to different cars to see what sound you like. Be careful if you're thinking of dropping your car. I've had mine on coilovers and the rear can't go too low as the exhaust pipes at the confluence get battered. Good luck! Quote Link to comment Share on other sites More sharing options...
nub Posted December 2, 2016 Author Share Posted December 2, 2016 I think I'd stick with CBE until I can find a cheap or 2nd hand HFC with resonators. Then before mapping I'd find a decent decat, again with resonators. There seem to be some cheap alternatives to the bigger brands and being that it's such a small section of the exhaust I don't see why the cheaper versions sound perform any worse than the £500 berk HFCs or however much they are Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
nub Posted December 2, 2016 Author Share Posted December 2, 2016 I'm very particular when it comes to exhausts. It needs to be quiet and refined enough yet still loud enough to open up the melodical engine note of the V6. I dont normally buy cheap stuff but in the case of decat pipes it's such a small section of pipe, as long as the welds and OD is good I don't see any problem. I've found some cheap resonated decat/test pipes and some cheap high flow cats. I'd purchase the latter purely to swap over for MOT and remap the car with the resonated decat pipes for maximum power. If I achieved 360bhp I'd be very pleased. If that's still too loud for me I'll have 2 smaller silencers added in the system which wouldn't cost more than £100 or so. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
nub Posted December 6, 2016 Author Share Posted December 6, 2016 I'm posting this in here too: Hi TORQEN & other traders. What's the best price you can do on these? As I'm guessing they must be the quietest best performing resonated decat pipes you can buy? But if I'm wrong please correct me. I'm thinking that logically the larger the perforated silencer the quieter it will be l. Below is the motordyne decat. And then this is a resonated fast intentions high flow cat which I think would be a quiet HFC, perhaps the most. Who can give me the best price on the motordyne decats ? I know ARK do a similar version but their Helmholtz chamber things look shorter. I'm also assuming that Helmholtz chamber is for effective or sounds better than your typical straight through silencer. That's what I'm trying to determine. It's really complicated this @*!#, trying to produce the best and balanced sound Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
nub Posted December 6, 2016 Author Share Posted December 6, 2016 Nvm I've decided the best sounding BY FAR is the motordyne shock wave band the motordyne decat ðŸ‘ðŸ‘ðŸ‘ðŸ‘😎😎 Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
sipar69 Posted December 6, 2016 Share Posted December 6, 2016 Sounds to me like the best solution for you could be one of less noisy exhausts - Stillen or Invidia for example - with HFCs if you want a good bit of noise on demand. Aside from cold starts, I can happily cruise along without attracting attention to the noise, but drop a gear and prod the pedal and it's a whole different story. Quote Link to comment Share on other sites More sharing options...
Jonny B Posted December 6, 2016 Share Posted December 6, 2016 I've got a stillen CBE with Berks HFC's. It isn't particularly loud and if you're driving through a built up area can easily keep the noise down by maintaining a lower engine speed. At motorway cruising speed it's not at all noisy or annoying. But when you do open the throttle it does sound good. I had the stillen fitted with the standard cats for a while and it was still far too quiet, only a fraction louder than standard but with a better tone. I've also had one of the switchable maps set for 'pops and bangs' so with my current set up and with Rev match switched on it sounds awesome on downshifts 😃👌 Quote Link to comment Share on other sites More sharing options...
nissanman312 Posted December 6, 2016 Share Posted December 6, 2016 i had invidia with decats on my supercharged z sounded epic when opening the taps but you could cruise without any intrusion Quote Link to comment Share on other sites More sharing options...
nub Posted December 7, 2016 Author Share Posted December 7, 2016 It seems that what I want is a HFC or decat which is resonated. But furthermore, the Helmholtz chamber which elinates certain frequencies. Likewise with a CAt back, ark Grip and motordyne shockwave use the same technology, yet are not particularly quiet as cat backs come. The Motordyne ART pipe is definitely for the win. If you simply want to reduce the noise then any resonated decat m/HFC is ok. Just look at the size of the fast intentions HFC resonator, it's pretty big. Yet this is the ART decat I would ultimately be acquiring The motordyne shockwave cat back used the same principle although it's not particularly quiet. It takes away enough of the bad frequencies though. The Ark Grip uses the same Helmholtz chambers yet has additional silencing so must be quieter than the shockwave I'll post a video of the sound I'm trying to achieve soon. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.