Thanks for the input
I am considering the info. but I am slaying several other dragons at the
moment. There may not be enough data at this time.
gene
>
>> Since I don't know diddly about exhaust systems. Talk to me about
>> the single muffler in the rear.
>>
>> design of exhaust systems.
>> required back pressure for the engine
>> required back pressure for the valves
>> if this is so good why didn't GM do it ?
>>
>>
>> Is this something that should remain stock. Don't want to be doing
>> something that will blow out manifolds, gaskets, etc
>>
>
>Gene,
> 1. The engine doesn't "require" ANY back pressure. The less you have,
>the more power you can make. Only caveat is that significantly lowering the
>back pressure tends to make a carburetted engine run lean (unless you rejet
>the carburetor). This can lead to burned valves and detonation.
>
> 2. Required back pressure for valves: see above. The only other
problem
>I know of regarding free-flowing exhaust, relates only to those racing
>engines with very short (usually individual) exhaust stacks. With these, if
>the engine is shut down immediately after a hard run (ie: very hot), cold
air
>travelling back into the exhaust stacks can warp the hot exhaust valves.
>(That's why drag racers cap their exhaust pipes after a run.) This is not a
>problem for us.
>
> 3. Why didn't GM do it? Well, there have been some improvements in
>exhaust design over the past 25 years.... Perhaps interference with the
>holding tank dump tube was a problem. (I believe GM routed it straght out
>the rear.)
>
> If you do it, be sure to check your fuel mixture and rejet as necessary.
>
>HTH.
>
>Rick Staples
>'75 Eleganza
>Louisville, CO
>
>
Genef -- 77PB/ore/ca
GMC MOTORHOME INFORMATION
mr.erf
http://www.california.com/~eagle/
