Airflow increased by 1.76lbs/min for $95

This is going to be my review of RRE's UICP. It came in the mail on Tuesday and I didn't get a chance to install it in until yesterday. The part looked great....except that UPS decided to play hockey with the box :disappoin

It took me about 1 1/2h to put it in, but if I did another one today it would probably only take 30 minutes. It was a very simple install and the fitment of the pipe was great. I only had to trim about 1/2" off the stock flexable tube, which was described on RRE's website.

Now for the performance aspect:

My max airflow @ 17psi before the installation was normally about 28.50 lbs/min. After the installation that was increased (similar ambiant air temps) to 30.26 lbs/min. 1.76 lbs/min for $95 (+$15 shipping). Not too shabby :grinno: .

Prior to the install I had tried to increase the boost and saw no increase in airflow. After installing the UICP I turned up the boost to 19psi and was able to get the airflow up to 32.15 lbs/min.

I also noticed that the response was more linear durning the spool period. Prior to the install there seemed to be a "jerk" as full boost set in, almost an instant where it seemed as thought the turbo was "turned on". This has leveled out and has a more consistent pull as full boost is approached. I now have even worse wheelspin in 1st meaning I can only accelerate in 1st at part throttle. As full boost is reached in 2nd gear it normally lets loose again. It never used to spin in 2nd unless I downshifted from 3rd at about 40mph. FWD Sucks!

So, total after the installation I was able to get an extra 3.65 lbs/min !!! :naughty: .

I am contemplating turning it up to about 21psi but need to take a look at some logs at 19psi before I start doing that. I'm also a little concerned about lifting the head at that boost pressure (I'm still on the stock head studs :disappoin ).

Questions:

1. Is there an approximate correlation between an increase in pressure and an increase in airflow? Is a 1.89 lb/min increase "normal" for a 2 psi increase in pressure?

2. If my log looks good at 19psi is it safe to run 21psi on the stock head studs?

Anyway, needless to say, I am very happy and would recommend RRE to anyone.

I'm sure that I could see a really big gain by replacing the stock cat back, but I really don't want to do that. Last time I had it up on the lift, I noticed a reduction in exhaust pipe size directly after the cat. It lasts for about 1' and then becomes larger in diameter. I'm thinking about removing that section and replacing it with a stock sized pipe. It sounds cheap enough and I'm courious to see if that increases the flow.

My guess right now is that my exhaust is the next and probably largest restriction in flow.

Anyone know what a normal EVO at 20psi flows? One with the same mods as mine + the cat back. I have heard of people flowing 44 lbs/min on the EVO, but I'm guessing that is with cams, 1g manifold, etc.

On 99's the install is a little harder because of the fuel vapor lines running on top of the bolts that you need to remove. Took me like 5 hours lol. I got my RRE pipe along with the 1g BOV for $60 total though. :) So why dont you want to get a cat-back?

Yeah, I think the law is called "Ideal Gas Law". Their in another one I would have to open up a book that talks about how Airflow and Pressure are related and how if one changes one will equally chage based on size & air volume. I keep wanting to saw Brewers law. but i did a search, and its not.

21 should be just fine with 35lb/min! I really don't know what the headgasket & studs mechanical threshold is. I'm sure it's expressed in some sort of mathamatical equation somewhere around here on the internet. Would be nice to know. Im's sure it has somthing to do with cylinder pressure.

Wow! Very nice airflow #'s. Now, how are you going to get to 44lb/min :tongue:

Yeah, I think the law is called "Ideal Gas Law".

Yeah, the good old PV=nRT . I thought of that but the equation doesn't account for flow restrictions (such as my cat back). Also, I don't know the temperature of the air after the intercooling. I'm sure I could calculate the temperature of the air after the turbo, but after the intercooler....I doubt it without a direct measurement. You would need to know the intercooler efficiency at different ambiant air temperatures, pressure drops etc.


So why dont you want to get a cat-back?


I hate the increased volume of an aftermarket cat-back. I would buy on that sounded the same as the stock, but I doubt that's possible. Increased flow = increased volume :shakehead

I have hear of some being louder than others, but I'm not about to buy one for $500, install it, then start the car and hate the sound. I'm such a wus! :lol2:

I hate the increased volume of an aftermarket cat-back.

You could get a custom made one with a couple bullet mufflers as resonators and keep the silencer in. Make the cat-back one long resonator lol. You could also get that valve so that it would only be free flowing and loud when you want it to be and quiet the rest of the time. Just some thoughts.

their is one law that explains how airflow and pressure are locked hand in hand. How if one increases the other will decrease.

I bought a $112 Megan Racing downpipe, $62 Megan Racing 3in inlet to 4in tip muffler (waiting to arive) and had Mitkee quote me in stone $125 for a 3in cat-back if i install the downpipe and supply them with the muffler!

I got a writen in stone quote from mitkee for a 3in Catback for $125

HUH.....is that for everything, installation, bending, muffler, etc. WOW! :grinyes:

For that price I would take the chance of hating it!

Could you take a picture of the quote or post up exactly what it says? That way I could take that over with me when I go to talk to them.

Thanks!

EDIT>

Nevermind, dopey me decided not to read your entire post! :grinyes:

I was looking on ebay and you can get a 3" Tsudo fireball exhaust for $189 + $70 for shipping. Does anyone have one of these?

I've heard their actually preatty good. Besides that. Stainless Steel is Stainless Steel. No matter if its mine, yours, or theirs. A few blokes on Tunners have them.

HUH.....is that for everything, installation, bending, muffler, etc. WOW! :grinyes:

For that price I would take the chance of hating it!

Could you take a picture of the quote or post up exactly what it says? That way I could take that over with me when I go to talk to them.

Thanks!

EDIT>

Nevermind, dopey me decided not to read your entire post! :grinyes:

I was looking on ebay and you can get a 3" Tsudo fireball exhaust for $189 + $70 for shipping. Does anyone have one of these?


I bought the Tsudo N1 clone exhaust. I think it cost me some where around there. Plus I bought a megan downpipe. I have no cats on my car and witht he silencer in. It was barely louder than stock, and it sounded twice as good and not ricey at all. Now I took my silencer out, and it's about eight times louder but still a nice sound. I would definately recommend the tsudo it may be cheap but it has a great sound and is put together really well.

Why dont they make these for GSXs! :cry:

I have no cats on my car and witht he silencer in. It was barely louder than stock, and it sounded twice as good and not ricey at all.


Do you have any idea if there was a flow increase over the stock exhaust with the silencer in?

It doesn't seem right that you can plug up 70% of the tailpipe and still get a flow increase over stock..... :screwy:

To give an example, typical airflow at 20 psi on a car with cams is 40 lbs/min. The 16 family of turbos is different since they are practically maxed out at this point, and the exhaust side is somewhat small. At any rate, thats the rule of thumb I use. For airflow increases with boost, I usually see 1 lb per 1 psi, on a 2 liter. On a stroker its a bit more of a gain per pound of boost, because of the extra displacement.

There are many many factors involved, but these are the guidelines I've come to use over the years.

To see those gains on a UICP is surprising! I wasnt logging airflow back when I did some of these early mods. Good info to see.