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SB
06-07-2002, 12:34 PM
I have a 1978 Biesmeyer 20' with stock 460, stock Hardin exhaust logs. 1) Anything I can do to improve these? 2) Someone told me I could put a crossover pipe between the two logs to help flow, any thoughts? 3) If I run a cam with longer exhaust duration, does that mean that there is more time for the exhaust to escape, so I don't need to worry about switching to headers?

hack job
06-07-2002, 06:38 PM
Originally posted by SB:
I have a 1978 Biesmeyer 20' with stock 460, stock Hardin exhaust logs. 1) Anything I can do to improve these? 2) Someone told me I could put a crossover pipe between the two logs to help flow, any thoughts? 3) If I run a cam with longer exhaust duration, does that mean that there is more time for the exhaust to escape, so I don't need to worry about switching to headers?
ok first off i have never heard any thing like that for boats now for cars that is what is done its called a h pipe or x pipe and i have never heard of that on boats. now for the question regarding the cam . it would mean that you would have more time for the exhaust to escape but that would not mean that you can keep the logs for ever. if you are running a mild motor( cam and dual plain manifold )than logs would be fine . they will not hurt you but if you want to put headers on the boat it might give you a little on you top end and mid range but they are a pain in the ass . there are many opitions for boats and i would look around .but kepp this in mind exhaust is very expensive . so make sure its the one you really want. good luck and let us know what you come too for a answer.
Tyson www.plumbersassracing.com (http://www.plumbersassracing.com)

Q-ball
06-08-2002, 01:31 PM
I know the logs I took off my boat were stepped on the exit. They are set up so you can have 2 different sizes of exits. (like 3" or 3 1/2" or even 4") just by cutting a little off the end of the log. Check to see that yours have the largest exits already utilized. Good luck!

SB
06-12-2002, 10:35 AM
Thanks, I'll check. Since my engine is almost stock, I'm trying to think of something cheaper than headers.

Shockwave
06-13-2002, 12:56 PM
Look on CP's site in the exhaust section and you can see a crossover pipe- it will do the same thing as it will on a car- enhance lower and midrange torque and also make the exhaust a little quieter. The bigger the crossover the better.
I would put one on mine if I had space.
HB