"LIke a mcdonalds straw vs a bk straw. Mcdee straw the spit ball comes out slower vs the bk straw thats smaller diameter. :"

Except, there is no spitball, just the air that pushes it. I am not sure I understand this analogy. Doesn't the air flow easier in the larger straw?

 

at a slower velocity, the trick is sizing so it's not too small, and not too big


800 $ for a full turbo back exhaust? This one is in my price range, all the others so far are way beyond what I would ever pay for an exhaust, and there will be a muffler option that's not too much louder over stock? Sense I commute a drone will drive me crazy, and attract LEO

 

I dont know, i wont be making the DP to fit the stock catback because it will restrict it. The stock DP mats up really quick to the stock downpipe so there is not enough space there for me to reduce the 3" down to 2.25" etc. Unless you want a 2.5" DP or so?

 

If you can turn wrenches ill let you turn your own wrench and let you save on labor.

 

I hae to take the kids ride for a spin and get my own data as for droning etc. I know when i drove it , it did not seam bad inside at all. I have to try I95 later on in teh week. Pictures is only my proto so there are some things i want to address on my end before i make a setup that I can ship.

 

The velocity coming out the smaller straw is more than the big straw.

Take a water hose , the pressure should be the same to your house. PUt different size fittings at the end. The smaller the fitting the farther the water goes out.

 

It goes farther, but not as much comes out over a similar time period as a wide open hose. Why is velocity more important than volume. The idea is to get gas out, not restrict it. Yes?
My comments and questions are not intended to argue, but to understand.

 

Doesnt sound too bad for the price.

 

WHen you eat up air, it expands and takes up more volume. When you cool it down it takes up less volume. Its still the same amount of air. At the end of the exhaust system, the exhaust requires less volume vs the front because its not as hot as the front. There is a balance between how fast you want it to come out yet getting enough of it out. If you put a pin drop hole in teh back, it will come out a whole lot faster vs a 4" hole in teh back. However it creates a big restriction. You need to find teh balance between having it come out the quickest yet not restricting it.

Now im telling you this not as a money marketing ploy but to tell you what will work for this car based on experience. I can market you a full 3" system and make more $ on it or i can sell you a 3" dp with a 2.5" catback and make less money on it. I can bend any of them and at the end its your $. I can only recommend but the decision at the end is up to the customer.

There is no way that the STOCK turbo that is on this car now will outflow a 2.5" FULL exhaust. IM making a 3" DP only because its added insurance for the stock turbo. This is based on some one takign the stock turbo and installing bigger wheels in it etc. Now the 3" Dp will be fine but still not closed to being maxed out.

Here is something to think about. YOu have tons of 400-500 hp cars with a 3" system. THis is more than double what your car can dish out yet its only .5" bigger in diameter (the tubing).

The less the back pressure the better for the turbo. Thats a fact. SO bigger teh better right? If thats teh case why dont we jsut go with a 4", or maybe a 5"? SImple, because those two pipes including the 2.5" is not a restriction for the stock turbo. YOu wont notice a difference in backpressure between the different sizes.

Hmm, lunch time?

 

Finally someone to put people in their place when it comes to the whole 3" vs 2.5" bs! I'm sure they still won't listen though...oh well, like you said, it's their money!

Welcome ExhaustDepot, excited to see more of your work!

 

I believe he stated that the full turboback (Downpipe included) was going to be around $750. At least thats the information I had posted in the previous thread before the admins deleted it.

*Edit* whoops, saw that you were talking about just the downpipe.

^--- Do some work and get off NAM Blake.

 

No man, you rlooking at maybe $700 for a full base system (no cat). Ill pretty much toss up a burger king setup where you will have it your way. Ill add options for aggressive, mild, with or with out meow, type-r sticker or not, DP wrapped or ceramic coated blah blah blah.

 

Haha... how much to make my car sound like that F50 I sent you with the Tubi exhaust?

 

Most likely you are looking at about $250 or so.

 

I think you left off a few zeroes.

 

No I did'nt. 1 ipod mini, a cheap amp and one marine weather proof speaker mounted under the car in teh back.

 

And some sophisticated computer software to cancel out my current exhaust note and link engine rpm's directly to said speaker?

 

You misunderstand my question. Pipe size is an engineering issue and beyond my knowledge to comment on. I am just asking why restricting flow (finger on a hose to make the stream go farther) helps exhaust get out faster. No criticism of your design is implied. My understanding is you want to keep the exhaust gas hot and moving quickly. I am just trying to learn a bit about available systems to decide how I want to spend my car money.

 

Thats just it, your not restricting flow if you dont have enough flow coming out to be restrictive. You dont flow enough with this turbo to have an issue with a 2.5" plumbing.

 

^--- Also, the least restriction possible doesn't necessarily mean extra power. some back-pressure in the system is advantageous. The design Hector is talking about involves almost SUCKING the exhaust out of the engine by using a funnel-esque design.

 

Go to a warehouse or something where you see the a/c ducts plumbed all over the place. You will see that the begining of the system is large in diameter. Then as it goes out more it gets smaller and smaller. Thats to keep the velocity up and get the air otu to the other areas. If it was all one size the fan would not be able to pump it all out to the end.

 

when can we see the finished product....?

 

As I said above, you increase the velocity of the gas as you step down in size, this pushes the gas ahead of it out, and moves the gas in stream along faster. There is limits, note it also increases back pressure, and uses some of the Kinetic Energy of the gas to increase the velocity.

 

I have a 2.5" Milltek Cat Back exhaust. At the time of purchase the DP wasn't available due to CEL/SES problems and about a month later Milltek withdrew it.

The Milltek just buttoned right up to the OEM downpipe. Love it no problems.

Are you saying you can make a 2.5" downpipe that will button up to the stock turbo and Milltek exhaust, not have CEL/SES problems, have a high flow cat that will pass emmission tests and improve proformance?

What's the price, what's the performance increase and when can this be expected to hit the market?

 

Your asking if i can make one and then asking whats the perf inrease. lol Ive never done one. THe problemw ith the stock DP is that there is a flair right at the end of the bend. It is not long enough for me to flair it.

What I can do though is make a DP for you and supply you with a loose flange. Any compitent exhaust should should be able to cut your miltek by about 3" or so and weld a flange on it. Then my DP with a flex will bolt up to your setup. This will give you a much better connection using a flange and it will support engine flexing better than the factory ball joint setup.