Clearance Clarence
 

Hey any first gen guys our there running the G-Force Tri-link & Panhard with the Racing Beat race exhaust system? The shop going the install couldn’t get the stock muffler back on because it interfered with the panhard. No biggie really as I planned on using the Racing Beat setup anyway, but now I’m not sure? I don’t want o have the same clearance issues?

I was looking at a car in my shop, and I don't think my exhaust design will fit in there.... actually, I don't think anything but something specially designed will fit. Of course, this car dumps under the passenger seat, so it's no big deal. ;)

If you do find something that works, let the board know! :D

Unfortunately, that’s what I thought. So what are you CSP guys doing for a (fairly) quiet system? I was thinking the RB race header and center section with an ISC muffler and fabing the connection or RB race header to the ISC muffler with a short connecting pipe and dumping it under the passenger’s seat? Anyone have any experience with the ISC muffler?

I use the G-Force Tri-Link & Panhard, and I had to ditch the streetport RB exhaust pipes. The stock Watt's link has too high of a rear roll center; the G-Force Panhard bar fixes the rear roll center problem on the 1st gen RX-7.

I bought an ISC header (makes more power than the RB header because it does not have the sharp turn right at the engine like the RB; the ISC comes straighter out of the engine.) I then built my own mid pipes. I built a 2 into 1 collector right before the rear axle, collector and diffuser run under axle, then I use a 3" straight thru Borla Stainless muffler after the rear axle. I run a PP 13B engine; this system produces over 300 rwhp and passes SCCA sound tech meters.

I have the G-Force set up and the RB full street port exhaust.

It fits. It is a bit of a trick to get it up in there but it is very doable. There was slight interferance between the muffler pipe and the bracket that holds panhard to the car on that side. A few taps with the hammer made it fit. It still vibrates a little bit until the car is warm, at which point there is about a 1/4" clearance.

This sounds good but what are your SCCA sound limits? At at least one place we run here locally we have a 90 db limit. It's measured at the entry gate which is a good distance from the track, but I don't know what that distance is, a couple of 100 feet maybe? Mike at ISC says their complete IT7 system measures 98-100db's.

Well the sound pressure decreases in proportion to the square of the distance. So you need to know if the 98-100dB is 50' or something else. At 100' that 100dB goes down to 94dB. 200' and it's 88dB. Every doubling of the distance equals a 6dB reduction.

Had you purchased a ISC Panhard you would not be having the exhause issues. The ISC Panhard mounts to the chassis on the left hand side & the axle on the right hand side. Exhaust clearance is not an issue. I have the 3 inch ISC exhaust traveling over the axle into a big assed muffler.

Have Fun ; )
David