US Headers & Exhausts NA

[project.r.racing]

That's the system I bought and will review it when it gets here. No one has made a reccomendation on what 4-1 system would be best to buy but very quickly the critizise a company that produces successfully at affordable prices without evidence/actual data but just heresay.

If you go back to page 1, you will see many point out the the pipe lengths are all different lengths. The lengths are quite easy to see from the supplied pics. You being a smart educated man with fluid dymanics expertise should have noticed the different length pipes?

[Black_Penguin]

So decades of successful header design = hearsay. Also those primaries are way too short, they might start working by the time the valves start coming out of the top of the head.

[Pamex]

I love the classic "I am the only dissenting opinion between many people THEREFORE THEY ARE ALL WRONG AND I AM RIGHT".

To be honest, for that price, why not buy a welder and a flex join and do it yourself? You seem so knowledgeable on the subject, it shouldn't be too hard for you.

[project.r.racing]

That's the system I bought and will review it when it gets here. No one has made a reccomendation on what 4-1 system would be best to buy but very quickly the critizise a company that produces successfully at affordable prices without evidence/actual data but just heresay.

If you go back to page 1, you will see many point out the the pipe lengths are all different lengths. The lengths are quite easy to see from the supplied pics. You being a smart educated man with fluid dymanics expertise should have noticed the different length pipes?

Deary me, its about the gases from each cylinder getting to the collector at the same time. If you look at vivid's equal length headers for the wrx sti, it is easier to understand.

NO!!!

It's about the gasses getting to the collector at differently evenly spaced times, so they cause a vaccuum effect for the other pipes.

They will only get to the collector at evenly spaced times if all the resistence and velocity are all the same. As the combustion of each cylinder is evenly spaced out between all firing cylinders.

[hks_kansei]

So, in formula 1 they try and reduce weight dramatically, down to every last gram.

Here is a Formula 1 V10, with tuned extractors.

http://upload.wikimedia.org/wikipedia/c ... anello.jpg

now, if you could get tuned length extracors by simply reducing the diameter, that would mean you could reduce weight, for example, the pipe on the rearmost cylinder could be half that length, saving weight on all that "useless" extra pipework.
and cylinder 1 would have less weight in the headers due to the smaller pipe being less weight than a larger one.

if diameter was the only possible variable here..... why would Formula 1 engineers not use it?



And I look forward to the review of your headers, no doubt it will be 100% unbiased and properly tested.
"the car runs"
"it sounds faster"
"it picked up 10kw, I can feel it, my mate said it felt faster too"

If anything you might get a cool exhaust note from the uneven exhaust pulses, but that;s about it.

[sailaholic]

Ummmm I think you missed something mx5 is naturally aspirated. Sti is not.

[tbro]

Yep=======length race tuned

[gslender]

There is a saying that I think applies here....

I learned long ago, never to wrestle with a pig.
You get dirty, and besides, the pig likes it.


Sent from my iPad using Tapatalk HD

[orx626]

Dupain, from your posts in this thread it is clear to me that you do not fully understand, or are able to effectively apply the fluid dynamic concepts you were taught at university whilst doing your Chemical Engineering degree. The reason I say this is that you would be agreeing with the majority of the advice that the forum members have offered if you did. I don't believe anyone here has agreed in full with your performance assessment of the headers you have purchased. Have you asked yourself why that would be so?

In general forum members don't take pleasure in telling other forum members that they are wrong or ill-advised...well I don't anyway. Like you some of the forum members here are very well educated at an engineering level, some have a wealth of experience, and in some cases they have both! This forum is here for MX-5 enthusiasts to help each other enjoy their passion and at times that requires the promotion of incorrect information, bad advice and flawed concepts to be flagged and discussed... especially those that are safety related. However, I digress.

All the best with your purchase.

[taminga16]

I have just found this thread . Asthetics are just so important.
Greg.

Look in the end, I'm reviewing a cheap, decent looking header with promised power gains.

Get the pic up if you can and have a look.

Dupain.

[ManiacLachy]

Yeah, Danny has no experience and doesn't know what he's taking about at all. Certainly isn't an expert. /sarcasm.

[jimmy_vee]

[emily_mx5]

It is clear that your knowledge vastly exceeds all of us lowly cartalk members.
I hereby suggest you pose your thoughts and questions from now on to miata turbo.

Definitely take the same argumentative approach there too.

[hks_kansei]

Actually Miata TUrbo would be a good one to ask.

There are a lot of members there who really know their stuff, including fabricators etc who make parts for a living.

They will be able to give you a good objective response.

[project.r.racing]

hks_kansei - hits the track, does autocross
sailaholic - builds and races race cars
tbro - builds and races race cars, mechanic by trade
gslender - hits the track regularly
orx626 - builds and races race cars, owns a mx5 performance shop
project.r.racing - kits the track regularly, does autocross, rally, motorkhana

and that is only the posters i'm aware of from this page alone. i think i could find more in this thread if i went looking.

no one is bullying you. grow up!!! there is a massive experience base you just accused of being sh!t talkers. look in the mirror. he is the sh!t talker. the only one doing any bullying is you. you have slagged of most poster and the entire australia population so far in this thread.