I'll have to get serious enough to take off my trailer hitch before I go for weight reduction in exhaust. However, I'm curious if King ever just removed the left exhaust and muffler to see if it made any difference. Lighter of course, and louder I'd guess, but given that one side looks as large as upstream pipe, it might not add significant restriction.

[QUOTE]Originally posted by Jason Saini
[B]

 

Not to say anything against either the JR Filter or the Mugen exhaust, but those dyno runs were done 6 months apart. How about doing the tests on the same day? Otherwise there are way too many variables to be able to make a fair comparison.

 

Gregg-

I'm working on a quick release mounting system for my hitch as we speak. Lets just hope it quickly releases only when asked........kinda scary huh.

As for the dyno....that's a good point.

[Edited by Mack on 05-21-2001 at 11:43 AM]

 

I think of my exhaust in two sections... the part right after the cat up to where the stock exhaust splits in two... and then the muffler section.

Now let me say that looking at the stock exhaust, I dont think that there's anything "wrong" with it until it gets to the split. It is straight and unobstructed. Any power to be gained from that front area is going to be from tweaking the volumes and locations of the expansion areas in that section (no doubt the reason for the famous "dead end"). But like I said, there's nothing wrong with that stock front half.

So when I started on my quest for the perfect exhaust the first thing I did was just to cut the stock system in half, just before the "Y". I had that cut flanged and then had two different "muffler sections" made. The first with a Thermal R&D muffler and the second is just a straight pipe, no mufflers.

So, depending on the noise restrictions of a particular event, I can choose the "quiet pipe" or the "LOUD pipe". The swap takes less than 10 minutes and I can do it with the car on the ground.

For giggles (and to be able to make dyno comparisons) I also had the stock mufflers flanged so I could put them back on as well.

I had all of this done at California Muffler (www.californiamuffler.com), all for the tune of about $300. Their work is excellent. If you're local, I can highly reccommend them.

Just this much alone I think is an excellent exhaust option for this car. It's an easy 35-40lb savings over the stock mufflers. It also sounds great. Is there slightly more power to be had by tweaking the front half of the exhaust? yes. Is it much? no. Am I going to tell you exactly what I've done or how much I've gained? ... no. After all, my competitors are reading this...

[QUOTE]Originally posted by Jason Saini
[B]...I'd be willing to wager that Jason's custom single either sacrifices torque or shows a marginal improvement.

 

I'm pretty sure one of those variables is a new short block, but I could be wrong.

I had a look at the mistress when she was on the trailer, other than the fact that two tips looks pretty cool I cannot see a reason for the duals. It would seem more efficent to run a single muffler and tip. However backpressure makes torque, having too much of a open exhaust will take away what little torque we have.
Like Jason said the mugen exhaust was designed and tested to make torque at the expense of overall hp. Autocross tends to rely on torque more than raw hp so every little bit helps. Also the note from the mugen is sweet! More of a low rumble than the typical mechanical wine, it's not too loud ot too quiet. Just about right in my book.

I think the time and effort required to make and test the right single exhuast outweighs the ease of buying one and putting it on. If I were to design a single it would have to use some kind of tuneable muffler like a supertrap and plenty of dyno time to get the numbers right.

 

That's a fair rebuttal, and without any dyno proof this is all just heresay - and as Mike w/Comptech stated, our dyno runs were several months apart and therefore not very conclusive. I can say that the old butt-dyno feels it down low. I drove a stock car and an HKS equipped car at Asheville and both felt dead under 6k compared to our car.

I will close with this... And this is the best response I can give to Mack's questions:

Niether 20lb. of weight nor 7 lb/ft. nor 3hp are going to make or break an autocross car. Either of the Jason's solutions to the exhaust problem are quite acceptable for a winning car. At this point it becomes personal preference... do you like the loud/racy sound and appearence of a single or the refined sound and appearence of the Mugen?

I just like saying we have titanium in our exhaust!

 

I knew you we gonna say that!

Damn!

 

I love the Mugen exhaust. I do wish it were a tad bit louder for the track, however.

It looks very nice. It sounds awesome - low rumble, not the high pitched sound of some of the others. It saves weight. It has titanium in it .

Until I see dyno results proving that another system is adding any appreciable power gains the Mugen was the way to go for me.

My $.02

 

[QUOTE]Originally posted by Jason Saini
[B]I will close with this... And this is the best response I can give to Mack's questions:

 

Brad-

Your assuming I "need" a driving school!

Seriously though that is always good advice and I intend to do that sometime next season. First I need to develop allot of bad habits so I can get my moneys worth!

-

I think a phrase that would best sum up what I've learned from this thread so far would be.....

When it comes to racin' you've gotta choose your own VooDoo.

What might work or be the best solution for me might not work or be the best solution for you.