Dual Exhaust on a 100?

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I thought I'd ask this question to see the consensus. Aside from the cost of dual exhaust. Are the performance and gas mileage gains worth it if any?

Are there drawbacks to D.E. a 100? If so what are they? I want my truck to last and It rarely sees and offroad use (if it does it is of the novice level).

I am mechanically inclined but not an engine wiz by any means.

What do you guys think?
 
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theRash said:
I thought I'd ask this question to see the consensus. Aside from the cost of dual exhaust. Are the performance and gas mileage gains worth it if any?

Are there drawbacks to D.E. a 100? If so what are they? I want my truck to last and It rarely sees and offroad use (if it does it is of the novice level).

I am mechanically inclined but not an engine wiz by any means.

What do you guys think?

As far as performance/MPG goes, It really depends on the particular design of the exhaust system that you are considering to install. I know that, from personal experience that it is hard to beat the OE muffler/pipe set-up, but I am sure that there are some systems out there that may help a little.

You mentioned the fact that you wont off-road your 100, and that is the MAIN reason that I wont add a dual exhaust to mine ( more pipe to smash when wheelin !)

Peace !
 
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I go to Ouray with it and the fam for camping trips but nothing offroad that requires a modified vehicle. I plan on getting a 40 for that. My 100 is more of a cool grocery getter for the wife and it'll haul a boat and trailer etc. 100s come with two catalytic converters. I didn't know that the OME setup was already pretty good. I always thought that the less effort an engine takes to breath, the more power it can devote to other things. Can anyone give me a ballpark fuel economy increase and hp increase? Still any downsides?
 
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hoser

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Generally speaking, a freer-flowing exhaust system on a naturally aspirated engine can give you slightly higher hp and but often less low-end torque. For an SUV, that rarely sees its upper rpm range, I wouldn't recommend modifiying the OEM exhaust.
 

Pskhaat

 
 
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Maybe at most 5% in the best world. Remember that engines, manifolds are tuned within reason to a particular rate of flow or as most people call the backpressure. I don't think manufacturers spend a great amount of time /perfectly/ tuning the exahust system, but increasing/decreasing does affect performance and characteristics positively/negatively depending on the driving, and I would assume that the ECU has it's parameter maps set to the factory exhaust. I would not think the improvement to be worth the investment.

That said, I also feel that the stock exhaust system could use a little better flow, but again, I don't think you'd get a whole lot more out of it.
 

spressomon

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Be careful not to reduce/screw up your low end torque by reducing backpressure with those types of exhaust systems...as has been stated here. My buddy with a Suburban did the same thing...looks cool in his eyes, but it wiped out his low end torque. Now he has to use low range almost at any hill...
 
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Thanks guys. I guess it was the backpressure I was thinking of that would be the negative. I'll stick witht the OM exhaust.

That said... What performance increasing suggestions do you have in mind? ei. I had heard TRD offers an after market chip as well as a supercharger? Any thoughts on those?

(no I didn't check to see if there was already a thread on these items)
 
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If you ran a decent set of extractors into a twin mandrel bent 2 inch stainless system with muffler and resonator on each bank, you would pick up quite a bit of throttle response, no loss of torque due to the small diameter pipe and would lose that god awful OEM exhaust system. Extractors will make a huge difference, though no point doing these if you are going to bottle up the system by using the OEM exhaust. Once you get the exhaust done, think high flow air filter and snorkel with a chip remap, or disconnect battery for 5 minutes, reconnect and drive. Make the ECu relearn and utilise the changes you have made.
 

bjowett

 
 
 
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The manifolds are horrible on the Toyota V8... I'd go so far to wager that they are the major bottle kneck in the exhaust system on the V8. Improving the flow of the after cat system may or may not give any gains depending on those...
 
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