89 suburban exhaust system
Willyswagn
08-15-2006, 03:28 PM
Finally need to replace the exhaust system on the 89 burb. Saw the following duel exhaust system at lmc:
http://www.lmctruck.com/icatalog/csb/t104.html
Questions
1) Would this bolt on directly to the original exhaust manifolds for my 89?
2) Would the only needed modification be to weld in a bung for the o2 sensor?
3) would there be a noticable improvement on power and/or mileage for my stock suburban.
This is just a hypothetical question as I know the catalytic converter issue is not addressed.
http://www.lmctruck.com/icatalog/csb/t104.html
Questions
1) Would this bolt on directly to the original exhaust manifolds for my 89?
2) Would the only needed modification be to weld in a bung for the o2 sensor?
3) would there be a noticable improvement on power and/or mileage for my stock suburban.
This is just a hypothetical question as I know the catalytic converter issue is not addressed.
sub006
08-23-2006, 08:16 PM
Couldn't read the fine print onscreen, but without the cat, if the pipes are at least 2 1/2 inches you MIGHT be looking at 1 mpg improvement highway.
With catalyst it is difficult to see much potential unless you live in a state that will allow a high-flow catalyst to be installed on EACH side (two total). In California you can only have one on a Sub, matching original equipment, and thus still have a single exhaust with two mufflers and tailpipes at best.
I run a single cat, Gibson muffler and 3" single pipe. One-half to one mpg improvement. Headers (1 5/8" Edelbrock shorties) haven't made a measurable difference, but do sound cool. I also have a K&N filter in the stock housing with a large velocity stack riveted to the air cleaner bottom (which seems to help as much as the exhaust for lots less $$$) on an Edelbrock manifold. And a Crane RV cam. With super dyno tuning I have a 383 that gets almost 18 mpg highway in a big heavy 1990 Sub. Best the stock 350 set-up could do was almost 16 mpg.
With catalyst it is difficult to see much potential unless you live in a state that will allow a high-flow catalyst to be installed on EACH side (two total). In California you can only have one on a Sub, matching original equipment, and thus still have a single exhaust with two mufflers and tailpipes at best.
I run a single cat, Gibson muffler and 3" single pipe. One-half to one mpg improvement. Headers (1 5/8" Edelbrock shorties) haven't made a measurable difference, but do sound cool. I also have a K&N filter in the stock housing with a large velocity stack riveted to the air cleaner bottom (which seems to help as much as the exhaust for lots less $$$) on an Edelbrock manifold. And a Crane RV cam. With super dyno tuning I have a 383 that gets almost 18 mpg highway in a big heavy 1990 Sub. Best the stock 350 set-up could do was almost 16 mpg.
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