[gearheadmike]

Ok so i know with exhaust mods it involves usually a jet change. My question is what about lengthening the exhaust system?
I plan on putting a 1985 Yamaha FZ 750 Genesis engine in my old 1950 Crosley car and would like to run the exhaust to the rear. Now i'm not sure if ill have to re jet it or not also the original mufflers will not be used.

 

[dropkicknick]

pretty sure length dosent matter, its about density... ba dum tiss

but all seriousness, aftermarket exhaust tend to have a higher flow as apposed to OEM which is packed with all sorts of **** like catalytic converters, mufflers, silencers, blah blah global warming etc.

since you plan on deleting a part of the stock exhaust, it will be less restrictive so a jet kit might be good. ive heard dynojet has decent customer service if you give them a call they can help point you in the right direction for which stage jetting and kit to buy

chyyaa

 

[Eye_m_no_angel]

Put the engine in as desired, put in some fresh plugs, run it for 60 miles or so, read the plugs, then re-jet or not according to what the plugs tell you. In other words, put it in with the exhaust as you like it then tune it up. :smile:

 

[SemiFast]

Hey, I had one of those bikes way back when.

What type of air filter or air box do you plan to use?

Even though the stock exhaust system is fairly restrictive the most restriction is in the stock air box.

If you use a free flowing air intake and a non restrictive exhaust system you almost positively WILL need to re-jet the carburetors.

If you're going to use the stock air box... See Eye's post, number 3.