enrique

I am researching exhausts for my fc and have a question. which is better? a stagered size exhaust such as the apexi gt or a straight throught like n1 or hks? I assume apexi did the stagered for a reason, but if they did why don't other companies do the same? TIA

tonyge

whats meant by staggered. going from one size to the next like a 2.5 to 3 inch set up?if so i would also like to know the answer to this

enrique

after relooking at apexi's site both the n1 and gt are stagered and both have the same diameter piping.
65-70-85 hmmm this has me confused. whats the differance between the 2

SidewaysFC

straight through is better...more flow less back back pressure...they taper down to fit on the stock cat, assuming yours is stock...you may have to go custom made if you 3" all the way through

enrique

I plan on no cats since this won't be my daily driver.

tweaked

iTrader: (4)

Straight is the way to go. As far as I can tell the only advantage of the stagered exhaust is for sound. and it doesn't help power.
Whe the pulse gets to the larger diameter, it slows down. this will change it's tuned frequency. My Ford truck has a stagered exhaust. ( don't think that is right term by the way). Starts out with dual 2" then to 2.5 then to 4". It has a very low deep kinda growl. A freinds truck wich is similar is pretty much the same exhaust but it is the dual 2" instead. It has a louder pop to it. I don't think it will have much of an effect in a rotary.
go straight.

rotarygod

iTrader: (1)

In theory the stepped exhaust design is better. However reality has shown that in about half of the cases it worked better and in the other half it did nothing so you decide. The fact that air slows down as it gets to the larger area and therefore has a negative effect isn't quite true. It is a different phenomenon that the larger diamter is taking care of. Even in a good constant area pipe, exhaust gasses will encounter resistance at a certain distance and actually slow down a little. The larger pipe placed at a strategic point will relieve this pressure with a small area increase and flow will actually increase. In a perfect world we would have a slowly expanding with length pipe that would never end. Obviously we can't do that. The unfortunate part is that without actually dynoing and building the system yourself, there is no way to tell if it worked better or worse than a typical straight system. Theory doesn't always apply to the real world. If both systems are out there on the market then there was probably a fair amount of research that went into those systems so either one will most likely work well. If you were building it I'd say go traditional.

RETed

A'PEXi runs their N1 style exhausts to make the best power for the Group N1 racing.&nbsp The Group N1 cars have to run stock engines, so the exhaust is tuned to work with the stock power plants and restrictions.&nbsp The stepped exhaust piping is supposed to keep low end power/torque up without hindering top end power.

The A'PEXi N1 exhaust systems were designed to work well with stock engines and turbos.


-Ted

V8kilr

I did one exhaust staggered,

was 2 1/8 on the straights and 2 1/4 on the bends

dont know if its better, would imagine so, but took to long to make and I never dyno'd it

enrique

I don;t plan to keep my engine stock for long, so I would like something that can work ok w/stock and better w/modified engine.

RETed

Then you're wasting our money.

If you like the look of the muffler, A'PEXi does sell the muffler alone with no pipes - just run your own pipes and get the muffler welded at the end.


-Ted

enrique

if I were to do that I would still end up with a bottle neck from larger pipes as the universal mufflers are smaller. I like the hks exhaust but at 1300 I think thats a little much.

1987RX7guy

iTrader: (3)

Like the man said "Speed costs money. How fast can you afford to go?"

enrique

I know its gonna cost money. but it doesn't seem worth the extra 800 for the 1/2 of diameter the piping gives. I will probably get the hks I just want to make sure that the costs are justifed over something that costs half of it that is just slightly smaller.

1987RX7guy

iTrader: (3)

When you look at the cost a mandrell machine you will realize why things cost so much. Not to mention the purpose of a business is to make money.