Hey all,
I have an 18hp Vanguard on a GDLT. I am wanting to wake this motor up a lil bit. Back when I was into drag racing and just going fast in my truck, I was always told "The more air in/air out is better". IS this true with these motors as well?

I have thoughts of doing the exhaust first, and was in touch with Micah for a single BPS SS exhaust. (this would be a single muffler that would usually be a twin muffler set-up)

My thinking is that these mufflers are used on 36HP and up motors. Since I have an 18hp motor, would this muffler have any real performance value/better sound since I would be only using one?

Can I achieve the same sound/performance from say a cherry bomb muffler or another type of round muffler found at JEGS or other performance shops?

After exhaust I would like to do a k&n air filter and possibly a new "stock" carb.

How important is the air in/air out and back pressure of the mufflers on these motors?

Thanks and sorry for the long read,
Lookinup

I don't know what the specs. are on a 18's exhaust ports, but the only exhaust that may fit it is a 23 hp BPS crossover.

Without any other mods you won't notice the gain from the exhaust except a little throttle response and a few RPM's

hey man, I got a 23 LA special mudbuddy, and had the same questions as you. wakin it up a little. my buddy who is a small engine mechanic helped me out. we opened up my stock exhaust and removed the baffles and cut a hole in the back and welded a pipe extension about 3 inches to it, thus doubling the exhaust. installed a k/n filter and really woke mine up. granted, not a bps and mikuni but also, not 1700.00 either. picked up about 300 rpms and about 3 miles an hour. gets out the hole a little faster too.

hay DRAKE1 give him some advise

Thanks all,
Drake1...is he the man on this subject?

Pm at ya about the exhaust and modified K&N air filter bud

Lookinup

PM me your email address, I can send you some sketches of an exhaust that I have put on both a 27 kohler and a 23 briggs. Not much to them. Also, If you really want to learn, read the book "Fundamentals of Intake and Exhaust Design" I know that suggesting a book on this site may be a bit of a stretch!!!

Mag10

Mag10,
PM on its way, thanks bud.
And suggesting a book is great.............as long as it has lots of pictures!

Lookinup