RS Bob's point is right on. As I alluded in my message, my modified exhaust made minimal performance gain. I had previously made my own air filters out of washable Uni foam, replacing the more restrictive paper pleated versions. I have also tried the individual K&N air filters in place if the air box. In other words, I have increased the flow capabilities of the "inna" and "outa" components to minimal effect. That leaves the head as the bottleneck in our GTS's. Steeli Dan rebuilt his 94 motor and tried replacing the cam with a FZR one, but didn't quite fit. The mechanic installed the stock intake cam with 4o offset, but that didn't help. Without doing some serious headwork - porting, different cam grind, larger valves (one, some or all) - to increase the flow rate of the head, you aren't going to achieve any significant performance gain. However, we all are under budgets and typically do things incrementally. A new, freer flowing exhaust system would prepare you for the next step besides looking and sounding better especially if you have a rusted out system to replace. And as I said, not going to decrease performance. With one more rally in Col the end of this month, my bike will be pushing 70,000 + miles. With my excessive oil consumption and this amount of miles, my winter project is an engine rebuild. Any information on head modifications (Porting, cam grinds, whole head replacement) would be appreciated and I think where we would see a marked performance improvement. -- Dave Biasotti // Fremont, CA ----------------------------------------------------------- Date: Fri, 12 Jul 2002 22:31:24 EDT From: [EMAIL PROTECTED] Subject: Re: aftermarket exhausts and other tidbits
You guys are getting on the right track with the exhaust systems. The statement that small tubes are for bottom end and large tubes are for top end is correct. One other thing you have to keep in mind here.......... an internal combustion engine is effectively an air pump. Its efficiency/horsepower is dependent on the volume of air it is capable of moving. Here is my point, overly simplified. you have three basic components to the engine, for the main purpose of processing air. The aspiration system, the cylinder head and the exhaust system. Increasing the flow in any ONE area may or may not yield a gain in performance. <snip> Whether it is worth the money/effort to obtain and install becomes very subjective. I think all that rattling was my $.03. RSRBOB
