Improving acceleration?
I second this motion!
And it's the same differences of linear expansion rates that are responsible for our transmission pan gaskets leaking all the damn time, right? And the fact that the bolts fastening the plenum pan to the manifold are too long is irrelevant, too, I suppose?

Aluminum's coefficient of linear expansion is 12.3*10-6 inches per inch per degree Fahrenheit, while steel's is 7.3*10-6 inches per inch per degree Fahrenheit, which yields a difference of five microinches per inch per degree. So for a delta of 200 degrees, that's two-thousandths of an inch per inch. It's, what, four inches between plenum pan bolts, so .008" total relative motion per gasket segment? If that's going to cause gasket failure we're in trouble all over the vehicle and not just in the plenum pan.
Aluminum's coefficient of linear expansion is 12.3*10-6 inches per inch per degree Fahrenheit, while steel's is 7.3*10-6 inches per inch per degree Fahrenheit, which yields a difference of five microinches per inch per degree. So for a delta of 200 degrees, that's two-thousandths of an inch per inch. It's, what, four inches between plenum pan bolts, so .008" total relative motion per gasket segment? If that's going to cause gasket failure we're in trouble all over the vehicle and not just in the plenum pan.
Last edited by Augiedoggy; Jun 22, 2010 at 09:09 PM.
140k on my engine and plugs are clean as new with 5k since I bought the truck....doesnt burn any oil either so..... I'm just saying you shouldnt assume....its an old truck and waiting till you have an issue before spending money on something that isnt broke aint always the best approach... Sometimes you guys post like you get so many cents on the dollar for every hughes aftermarket plenum kit sold.... lets help him find whats actually causing his issues with symptoms and facts here rather than blind advice on things to spend money on.... He has never stated wheather he in fact has largher tires or not....if he has 31" or larger tires chances are the gears are factory and that could be the biggest contributor to his power woes...
ALso, APS sells the plenum kit too, for those who think I get money from hughes for telling about their products (funny how you do not mention hemifever with hughes).
You chimed in with the tranny, i chimed in with a tuner. Probably the #1 best bang for your buck that increases performance and MPG.
Need to know if the OP has the death flash as well. (although, I will grant, it is rather likely......)
Other stuff to know:
Tune up parts?
Fuel Pressure?
Various sensors doing their job?
TV cable adjustment? (if it isn't shifting properly.... well, it just doesn't go like it should)
IS the plenum blown??
Possible partially clogged cat?
Restriction elsewhere in the exhaust?
Other stuff to know:
Tune up parts?
Fuel Pressure?
Various sensors doing their job?
TV cable adjustment? (if it isn't shifting properly.... well, it just doesn't go like it should)
IS the plenum blown??
Possible partially clogged cat?
Restriction elsewhere in the exhaust?
If the OP wants to spend $150 to fix a $30 problem that he may not even have, it's his truck, his money, his time, and not my worry. But if he wants to approach his problem more intelligently than that I'd like to help him to do so. Part of that endeavor is to expose the fallacies in the cargo cult mythology so that he might make his own informed decisions, and that's why I'm making noise about it.
Now, if someone comes along who can use science and engineering to convincingly argue that the steel plenum pan is bad engineering, I'll gladly alter my view in accordance with those facts that are new to me. I've been adjusting my views on things throughout my life, and this might just as well be the next thing about which my mind changes.
In the meantime I'd like to participate in getting 0verdrive happy with his truck's performance because that's part of the reason I visit this forum. So far it sounds like he's got the right approach in mind, and the only thing I'd add to his current plan is that if he's going to stick to external bolt-ons for performance he might be better served by the Superchips tuner over the SCT because:
- It allows tire size adjustment
- It comes with a canned "tow safe" tune
- He has no need of custom tunes
What does this argument from authority have to do with ignoring science and engineering in order to perpetuate cargo cult mythology in this thread?
If the OP wants to spend $150 to fix a $30 problem that he may not even have, it's his truck, his money, his time, and not my worry. But if he wants to approach his problem more intelligently than that I'd like to help him to do so. Part of that endeavor is to expose the fallacies in the cargo cult mythology so that he might make his own informed decisions, and that's why I'm making noise about it.
Now, if someone comes along who can use science and engineering to convincingly argue that the steel plenum pan is bad engineering, I'll gladly alter my view in accordance with those facts that are new to me. I've been adjusting my views on things throughout my life, and this might just as well be the next thing about which my mind changes.
In the meantime I'd like to participate in getting 0verdrive happy with his truck's performance because that's part of the reason I visit this forum. So far it sounds like he's got the right approach in mind, and the only thing I'd add to his current plan is that if he's going to stick to external bolt-ons for performance he might be better served by the Superchips tuner over the SCT because:
If the OP wants to spend $150 to fix a $30 problem that he may not even have, it's his truck, his money, his time, and not my worry. But if he wants to approach his problem more intelligently than that I'd like to help him to do so. Part of that endeavor is to expose the fallacies in the cargo cult mythology so that he might make his own informed decisions, and that's why I'm making noise about it.
Now, if someone comes along who can use science and engineering to convincingly argue that the steel plenum pan is bad engineering, I'll gladly alter my view in accordance with those facts that are new to me. I've been adjusting my views on things throughout my life, and this might just as well be the next thing about which my mind changes.
In the meantime I'd like to participate in getting 0verdrive happy with his truck's performance because that's part of the reason I visit this forum. So far it sounds like he's got the right approach in mind, and the only thing I'd add to his current plan is that if he's going to stick to external bolt-ons for performance he might be better served by the Superchips tuner over the SCT because:
- It allows tire size adjustment
- It comes with a canned "tow safe" tune
- He has no need of custom tunes
Using your expertise:
Aluminum's coefficient of linear expansion is 12.3*10-6 inches per inch per degree Fahrenheit, while steel's is 7.3*10-6 inches per inch per degree Fahrenheit, which yields a difference of five microinches per inch per degree. So for a delta of 200 degrees, that's two-thousandths of an inch per inch. It's, what, four inches between plenum pan bolts, so .008" total relative motion per gasket segment?
Alright, that is EVERY TIME the car is brought to operating temperature and then cools back down. It is the REPEATED heating and cooling that causes separation. The more heating (and the higher the temp) the more of a gap will be when it cools back down. SO lets say that there is a permanent motion of .0001 per time the vehicle is operated, and bigger when the temperature is greater than operating temp. Not to mention greater during winter months when the cooling is faster upon shutoff AND the heating is faster upon startup.
1. You run the engine hot (because of failed water pump or radiator or thermostat) then the expansion is greater and the more warping is done.
2. You are towing, which causes higher temperatures...more expansion.
If you live in cold weather areas, the temperature difference is greater, and the metal cools FASTER.
What happens when you cool heated metal quickly? If becomes brittle and warps.
THis is also a reason why head gaskets leak because of overheating. And what are you supposed to do when you overheat and you have aluminum cylinder heads? You get them resurfaced to home them straight.
And you have hardly used science in any of your arguments, you have been using opinion. I don't know what bug crawled up your ***, but you like to be opinionated without any bearing or reason. Then when confronted, you turtle up and dissapear (reference to the thread where you said i was dishonest for offering someone employment advice.)
Last edited by CPTAFW163; Jun 22, 2010 at 10:47 PM.







