First, difference cource and place for autocross means the variable between the competitors is the same, instead of me getting faster because I know he course and the place has more rubber from day before.
Sorry that you don't know the variables in autocross. The comparison was done to other driver/car with consistent time.
As for drifting the N1 duals is better too, since I modulate throtle at high RPMs.

I have both the RB and the N1 Duals. Switch from RB to N1, then N1 to RB, then latest is RB to N1. So I have the first hand experience in this matter.

The High Flow CAT that I have flows much better than the stock CAT. The stock cat probably has 2 or 2.5 inch diameter pipe, with big CAT structure. The HF Cat has 3 inch pipes, meaning more flow there by itself.

Anyway. I got more low end with the RB, and N1 with silencers on. Very good for tight autocross and city driving. The open N1(no silencers) is very good for wide autocross, drift, race track(I don't mean drag track, but road course).

 

it was Wael's web site that dyno comparison between the hi-flow cat and the mid-pipe. I agree, the cat, hi flo or stock, would be the biggest restriction, not the muffler on the car. When you can see through the muffler and see the pipe on the other end it's going to flow better than a porous brick inside the cat, hi-flow or not.

Tim

 

Well not to get into an argument about tires but, There would be soo many different compounds of rubber on the track that the traction would be a minor increase if at all. Unless every one is using a spec tire in AutoX where your at.IMO and experience.

Anyways to move on, What Tim Benton said.

And since you do have both, and youlive in a motorsport infested state. I would like to find a place to flow the 2 exhaust systems. I would even help pay for it if we can find a place. In the mean time, I am going to contact RB and see if they can provide any flow #'s for their exhaust's.

 

I don't have both anymore... The RB was sold to a happy buyer 3 weeks ago...That is when I saw how tiny the pipe of the stock CAT is.

I kept on wanting to keep the RB, but motorsports demand for better IC and the quick dissapearing tires overule storing the RB.

 

Surge,

I really do not know how you could say something like this. The Racing beat cb is a "STRAIGHT THROUGH DESIGN"
It is no different, with respect to flow, that any other single piped 3 inch exhaust that is made for the 7.
The only reason that the N1 duals flow more is because they are duals. Even with this the difference is probably minimal.

I would be willing to bet that if you put a single tip RB catback up against a single tip Apexi exhaust, or any fart can for that matter, the power results would be very similar.

 

I'll chime in here...I used to own the RB dual tip. My car made 298 rwhp on a mustang dyno. I wan so pissed off about it that my tuner (Mohammad at MZM International) suggested I try the Apexi N1. We pulled the car off the dyno put on the N1 redynoed the car and the car made 335 rwhp. The only thing that was changed was the exhaust. So you can take that information however you like...but the dyno doesn't lie...

As for the silencers the best I could ever run was 11.87 with them in and 11.70 with them removed...

I wish my N1's sounded like the RB...

 

OWNED lol

although I suspect some heatsoak or something going on I dont think theres a 37rwhp difference in catbacks hahaha

I also don't understand your runs with silencers in and out. When I had the silencers in on my car I know Id barely make it into 13s and without them I ran 12.8 with my eyes closed and rolling off the line with 2.2-2.3 60 times.

jesuscookies thanks for putting your comments in such a polite manner. The reason I think the rb catback sucks is because ive raced 2 other 7s with the same or more mods than my old fd and I had the n1s and would blow them away that being the only difference in mods or maybe they had more mods on me but with the rb catback still.

so although id like to agree with bills comments 37rw is too much difference for catbacks only and .17 difference in 1/4 mile time silencers in and out makes no sense to me either unless they were custom made silencers ??

 

I'm a polite guy

Anyways, Someone should test these 2 exhausts. One after the other, same dyno, same day, same hour, same car.

I think plenty of people on here would be very interested in the results. Until I see proof like that I would have a hard time believing anything different than what I said.

 

I refuse to believe that there is a significant horsepower difference between the Racing Beat and most other exhausts. The RB is a 3" pipe leading to a y-section muffler that is straight through. The only thing that could be slightly restrictive is the turn right before the muffler.

There is no way in hell that one catback is going to make 30+ more rwhp than another. I would expect a scientific comparison to result in no more than 5-10 rwhp between any aftermarket exhaust, even at high power levels.

 

 

I am going to dyno test a few cat-backs in the middle of June. I think I can add the N1 dual to the list since a friend has one in the Atlanta area. Not sure if someone has the RB catback....I'll ask around.

I plan on dynoing the following cat-back on the same day, same car.

PFS
Greddy Titanium
Blitz nur spec
Apexi ni duals.

About the 37++ hp difference, just a little more information is needed. Did the car have a cool down period before you threw it on the dyno or did you arrive at the dyno, maybe wait 5 or 10 minutes and then do the runs? Then how long of a wait was it from the 298 run to install the Apexi unit and then dyno again? You could possible see that much if your 298 was a heat soaked run and the apexi run was after a nice cool down (in front of the dyno fans) while you were installing the apexi catback...that would take 30 minutes to atleast unstrap, remove, install and restrap it (all while in front of the fans). So it is possible, just not a true representation.

Tim

 

At least an hour cool down.

 

n1s are nasty sounding around 2-3k rpms on the highway... with silencers is probably worse than stock and still is very loud.

i have the rb dual on right now because the n1s are so ******* loud. i'll do some comparing during the summer. using a midpipe will probably make a bigger difference between the two i think

 

N1 Duals sounds really cool when the turbo control opens after 4500rpms. It just get so loud...I really like the echo running thru canyons, tunnels, double decker bridges....

 

Other than noise level--any other drawbacks to the N1 duals?...any bumper melting or anything like that? Has anyone had any experience with N1 dual and Bonez hi-flow cat?

Thanks.

 

I haven't had any other problems with the Duel N1's. I like the **** out of em, but a cop here in town doesn't.

 

Think about adding the stock muffler on that list too. It would be very interesting to see how restrictive it is.

 

Here's the story. I made 3 power pulls that day (287, 296, 298 after spending some time tuning. The final pull was 298 rwhp. So at that point the car was probably heat soaked. (Remember the most power was from the final pull.) The car was off the dyno for about 30 minutes before the 335 pull. I too don't think anyone can expect 37 rwhp simply by changing their catback. However, in my situation it made 37rwhp difference...

Maybe I was just lucky

 

I can't wait for some dyno test result.

 

Try to do the tests on a Mustang dyno or dynapak. Yes, the numbers will be lower than most of us are used to but the results are more consistent with those types of dynos.

 

Would be interesting to see the results. Back when I made 412 with the BNR's that was with a Pettit dual tip cat back which I always heard is just the RB rebadged. I wonder if it would have made a lot more with a different exhaust? hmmmmm

STEPHEN

 

I thought the old RB dual tip exhausts had two tips on them that had a cross sectional area LESS than a 3" pipe. Their new design has larger tips, or so I have heard. Something to keep in mind when talking about "X number of years ago I did this or that."

 

If Jason ships my RB today, I should have the RB and the Duel N1 cat backs in my hands this Friday. To bad I don't have access to a dyno.