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Re-post from current Grassroots Magazine December 2016 issue proving yet again that our straight through mufflers (Race, SuperStreet, SuperStreet Twin Tip) flow equal to a straight pipe. Grassroots got peak gains of 8hp at the wheels with just the muffler change.

Ron Bauer ran our shorty 4-2-1 header at the last Nationals, his gains over stock below...over 25hp gained at the wheels toward the top end with solid gains everywhere!

Fun coastal drive morning in the Good-Win Racing Project RF

Our friends at 949 Racing are working on tune for our ND Longtube Setup. Below is where they are so far with our SuperQ muffler at the back. Difference in peaks is over 20hp, and at 6500 rpms the gain over stock is over 30 hp! Getting results with the longtube takes a lot of work, they are putting in the time and starting to really get the results, nice work! They have Shiv's OFH too, and got similar peak but far less midrange.

Just out of curiosity, what were the numbers on the OFH. I'm not worried about getting rid of my long tube because I want the higher average power, but I really want to know what the gains are versus advertised on his setup. 20whp seems to be about the max gain from any exhaust on 91 octane.

They didn't give me overlay with OFH but when they are done I will ask for that. I know another of the guys that went to Nationals who was just 2hp more with our longtube for peak compared to OFH, though about 10 ft/lbs stronger on torque through most of the midrange, and that does not surprise me. A shorty is about peak number, and a longtube is about total area under the curve as you know. Mat's first pulls with our longtube were less peak power than with our shorty, and only with a lot of work did he get the peak to higher than our shorty.

The comparison I would like to see on same car is shorty vs shorty...our shorty against the OFH. Ron Bauer's chart further up the page was 166 hp on dynojet with our shorty and so far all the customers in the real world with OFH that I have seen on same dyno have been less.

I'm sure that their Super Q muffler selection hurts the power number a little too. I know he likes a quiet muffler though.

NathanD277 wrote:I'm sure that their Super Q muffler selection hurts the power number a little too. I know he likes a quiet muffler though.

You hit the nail on the head there, our straight pipe designs are fundamentally more flow efficient (Race, SuperStreet Single Tip and TwinTip). We worked hard to make flow pipe connecting to side entrance of SuperQ as smooth as possible, nice mandrel bends all the way to it, and through it....but any muffler that takes the long route around the space under the trunk costs about 5hp in our experience because that long snaking path is just less efficient than a straight pipe design that goes direct from midpipe out the cutout in the bumper. That's a big part of what is motivating our new MaxMidpipe design work, to enable more folks to use our straight pipe designs and get more result from the complete systems. The results from 949 Racing above are using SuperQ too, because Emilio likes it quiet. I am going to loan them a SuperStreet in the hopes they finish their work with it so we can see that additional bump in their results.

So, I stripped one of the exhaust studs with my attempt at a jam nut technique. I got it out finally. I'm going to temporarily replace it with a 2.5" 3/8" - 24 hex head bolt with a washer. Do you know the PN for the stud? Or should I bother?

I would not bother, if you have bolt with correct thread then you have replaced the stud with a much easier item to use.