Custom Exhaust
02-18-2007, 03:03 PM
#11
Junior Member
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You need to understand that when you list your mods in a topic, you open them up for discussion. That'* the way it is, and you can expect it in the future, just like any other owner here.
It'* important to state here for the benefit of OTHER members that read these topics that the IAT module does nothing for a car with a MAP sensor, and it may richen your mixture for a short period of time until the O2 sensor detects it, and re-adjusts you back to the preferred mixture ratio. Too rich is NOT good for performance. Lean or rich both hurt you. OBD2 cars with a MAP sensor will not gain any timing by tricking the IAT, either.
On your exhaust, losing the U-bend and keeping the stock piping will benefit you the most right away. Doing a high-flow cat at the same time will save you a little in labor.
Otherwise, you won't gain from a muffler change. Future exhaust changes should be forward of the downpipe. Either PEM'* or Headers when you cam or change rocker ratios. A larger downpipe and/or piping will hurt your low end performance.
It'* important to state here for the benefit of OTHER members that read these topics that the IAT module does nothing for a car with a MAP sensor, and it may richen your mixture for a short period of time until the O2 sensor detects it, and re-adjusts you back to the preferred mixture ratio. Too rich is NOT good for performance. Lean or rich both hurt you. OBD2 cars with a MAP sensor will not gain any timing by tricking the IAT, either.
On your exhaust, losing the U-bend and keeping the stock piping will benefit you the most right away. Doing a high-flow cat at the same time will save you a little in labor.
Otherwise, you won't gain from a muffler change. Future exhaust changes should be forward of the downpipe. Either PEM'* or Headers when you cam or change rocker ratios. A larger downpipe and/or piping will hurt your low end performance.
02-18-2007, 03:04 PM
#12
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Get 2.5" down pipe, 2.5" inch hight flow cat and the u-bend delete. Unless you plan on running a turbo you will hinder your setup with a 3" system.
Also check out http://www.clubgp.com/newforum/tt.asp?appid=36. The l36 guys are a nicer crowd then some on Clubgp and you will get great advise on getting that L36 moving.
Also check out http://www.clubgp.com/newforum/tt.asp?appid=36. The l36 guys are a nicer crowd then some on Clubgp and you will get great advise on getting that L36 moving.
02-19-2007, 11:09 AM
#13
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..my point is that i simply posted asking a question about the exhaust project, people asked for my mods, i assumed it was to gain a better view of what i should/shouldnt do with the exhaust..i didnt put it there so that people can just bash whatever i have done..the post was in regard to the exhaust and half the comments back have been regarding my mods..anyway its all good w/e thanks 4 ur help
02-19-2007, 11:19 AM
#14
Junior Member
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Nobody BASHED your mods, so quit twisting it around. We gave you ADVICE based on our EXPERIENCE, and your mods do have an effect on your exhaust choices.
I'm not sure about Olds, but with Pontiac, all our exhaust is mandrel bent stainless. You may want to research yours to be sure.
I'm not sure about Olds, but with Pontiac, all our exhaust is mandrel bent stainless. You may want to research yours to be sure.
02-19-2007, 12:07 PM
#15
Retired
Certified Car Nut
Oldsintrigue, please do not think we are bashing you, or your mods. As Wren has already said, we are only telling you based off of years of experience with hands on and from experimentation.
I use to run Bosch +4'* too. Until I came here and seen what they don't do, then I switched. Noticed a difference in the butt dyno and the wallet.
I use to run Bosch +4'* too. Until I came here and seen what they don't do, then I switched. Noticed a difference in the butt dyno and the wallet.
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2002 *-10 5.7 V8
2023 Jeep Rubicon Diesel
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2002 *-10 5.7 V8
2023 Jeep Rubicon Diesel
02-20-2007, 12:52 PM
#18
Junior Member
Posts like a Ricer Type-R
Originally Posted by willwren
Originally Posted by willwren
Bosch acknowledges a problem with using their Bosch Platinum spark plugs
in engines with ignition systems that employ 1 coil for each pair of spark
plugs (also known as a "waste spark ignition system").
The problem that Bosch has acknowledged when using their Platinum plugs
in engines with waste spark ignition systems stems from the tendency of
electrode metal to get transferred depending upon the polarity (direction
of current flow) of the spark. In waste spark ignition systems, 1/2 of the
plugs always see reverse polarity sparks. Given the very narrow platinum
center electrode of the Bosch Platinums, performance will be degraded more
significantly when reverse polarity sparks will cause material to be
transferred from the large ground/outer electrode onto the narrow platinum
center electrode'* exposed end surface.
in engines with ignition systems that employ 1 coil for each pair of spark
plugs (also known as a "waste spark ignition system").
The problem that Bosch has acknowledged when using their Platinum plugs
in engines with waste spark ignition systems stems from the tendency of
electrode metal to get transferred depending upon the polarity (direction
of current flow) of the spark. In waste spark ignition systems, 1/2 of the
plugs always see reverse polarity sparks. Given the very narrow platinum
center electrode of the Bosch Platinums, performance will be degraded more
significantly when reverse polarity sparks will cause material to be
transferred from the large ground/outer electrode onto the narrow platinum
center electrode'* exposed end surface.
http://www.brickboard.com/ARCHIVES/1...10003481.shtml
And it'* not just them or us:
http://www.taurusclub.com/forum/inde...showtopic=2915
AT LEAST a 36.25% failure rate in our sample size of 80 vehicles
17.5% failed immediately
Another 18.75% that didn't fail immediately failed within 20K miles (premature for a platinum plug)
There are still another 31.25% that are working so far, but haven't accumulated 20K miles yet. So they are "up for grabs" statistically, an could inflate that 36.25% failure rate even higher.
Still want to gamble?
Dan
AT LEAST a 36.25% failure rate in our sample size of 80 vehicles
17.5% failed immediately
Another 18.75% that didn't fail immediately failed within 20K miles (premature for a platinum plug)
There are still another 31.25% that are working so far, but haven't accumulated 20K miles yet. So they are "up for grabs" statistically, an could inflate that 36.25% failure rate even higher.
Still want to gamble?
Dan
I suggest you trust us. We base our opinions on Bosch plugs FOR THIS APPLICATION on our own personal experience and that of our members, as well as research.
If you want to say "Gee, I wonder if it'* true?" and you have the budget, by all means, go buy them and try them. You may or may not have problems, but the VAST majority of those 3800'* on this Forum that have tried them have had the same negative experience.
Based on all this, we will CONTINUE to suggest alternatives to Bosch plugs in 3800 GM FWD applications (as well as other applications if deemed necessary).
Your call.
02-20-2007, 12:54 PM
#19
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A friend of mine has a GP GT (same chassis) with a 2.5" DP, with the U-bend and resonator removed. Sounds pretty good with the stock mufflers.
You'll get some better top end power too.
You'll get some better top end power too.
