Don't hurt me for asking, but...

Gary Durden

Active Member
LOL Rahob, I can't wait until you start the next upgrade. I will have my popcorn ready. You pulled a lot of heavy weights into this discussion. The next one should be just as much fun. I remember the days when we put on a 49 turbo with Terry Huston down pipe, blue top injectors, removed one screen from the MAF, straight maf pipe with a K&N filter under the hood, raised the boost, new chip, alky kit optional and called it a day. Those were the days.
 

earlbrown

runs with scissors
So like I've said, and based on what I've learned from this thread, I've ruled out cold air kit, just like previously mentioned, I don't want to be cleaning the streets, and the extra restrictions with the bends. I am thinking of going with the 3.5" pipe with the LS1 sensor. According to what's been posted, it should be more then enough flow for at least how I have things envisioned for now.


That will support all the power you plan on making for a long long time.


....and ''cold'' air will make less power since power comes from heat... , but that's a different scientific discussion for another day...
 

Mr.Spool

Well-Known Member
Just quoting myself in case anyone else tries a search like me with these words and comes across this. Flow rates for MAF sensors.
that doesnt mean a thing,unless the turbo is all in.
 

Rahob

Member
Earlbrown, I'd really like to know how the heat has more power works sometime. I'm not saying I don't believe you, just curious. I know fire needs air, fuel and heat too grow, so I'm assuming might have something to do with it?
that doesnt mean a thing,unless the turbo is all in.
What do you mean, unless the turbo is all in?
 

V6sleeper

Well-Known Member
My 2 cents..
In my findings over the years and multiple combo changes i found that the biggest pipe 3.5" or 4" with the best maf sensor (ls1) with the shortest route to the turbo compressor and the longest filter 9"-12" works the best for spool up assuming you have an aftermarket turbo, ive had a few cold air kits in the past best being the Tin man and worst being the Kenne Bell, since the air is being heated up and compressed anyway by the turbo i dont think its worth the trade off of spool up difference between the two even if there's a big difference between ambient and engine bay temps.
 

earlbrown

runs with scissors
Because an internal combustion engine uses heat to push a piston down. More heat equals more push.


That's why modern cars run around 200F and don't have cold air kits (unless they're a special car that's marketed with ''race car'' stuff on them.)
 

Rahob

Member
I appreciate everyone's helpfulness! Thank you very much! Looks like I have my answer! Before I move onto this project, I'll be getting the Scanmaster G, followed by exhaust then this.
Thank you again!
-Rob
 

earlbrown

runs with scissors
If you still have a corrugated tube (probably with a hole in it), I'd see about getting the scanmaster and MAF pipe kit right off the bat.
 

Rahob

Member
If you still have a corrugated tube (probably with a hole in it), I'd see about getting the scanmaster and MAF pipe kit right off the bat.

Yes, and yes unfortunately, just happened to notice a slit in it where it's attached to the maf sensor. I think it could have been from the clamp cutting into it.
 

~JM~

Wrinkled Member
Perform a search on:

"Smokey Yunick + hot-vapor technology"

Or...

"Smokey Yunick + Fiero"

I remember the first articles on this concept that were printed in Hot Rod magazine. Interesting!
 

Mr.Spool

Well-Known Member
Earlbrown, I'd really like to know how the heat has more power works sometime. I'm not saying I don't believe you, just curious. I know fire needs air, fuel and heat too grow, so I'm assuming might have something to do with it?

What do you mean, unless the turbo is all in?
When the shaft speeds/compressor and turbine wheels are being spun at their greatest potential.
 

Rahob

Member
I few pages back it was recommended I go with an AC Delco sensor, anyone have experience with turbotweak's LS1, it's a "plastic, replacement for the older aluminum LS1 sensor". It seems they very reputable, just from how much I've read about them on here. Just wondering if anyone's had experience with that sensor.
 

BRAD_PADGETT

Well-Known Member
I few pages back it was recommended I go with an AC Delco sensor, anyone have experience with turbotweak's LS1, it's a "plastic, replacement for the older aluminum LS1 sensor". It seems they very reputable, just from how much I've read about them on here. Just wondering if anyone's had experience with that sensor.

I have the new black plastic LT1 sensor. It works just fine with no issues. It looks better if you want the stock appearing look.
 

Nigel

Active Member
Because an internal combustion engine uses heat to push a piston down. More heat equals more push.


That's why modern cars run around 200F and don't have cold air kits (unless they're a special car that's marketed with ''race car'' stuff on them.)

Max efficiency at road speed vs max power production has to be separated.

If interested you can go lookup/figure out the heating value per unit gasoline and the equivalent of what is put out to the wheels, take the difference and figure the efficiency of the engine. You can do this for various operating points, and determine what are the driving factors that determine max HP and max efficiency. Max HP is going to be dependent on maximum mass flow through the engine. You don’t want to blow it up, so it has to be a sustainable process. Max efficiency is extracting every last BTU from the fuel to maintain road speed.

In order to determine the effect of inlet air temperature on power production, the additional mass flow and so the additional fuel and heating would have to be considered against the energy to take the charge from 90F to say 1500F(arbitrary guess) vs taking the charge from 150F to 1560F. Just remember the 90F charge has more oxygen and fuel than the 150F charge. I’m sure that is over simplified, but it paints the concept, because the 90F charge has more fuel, peak temp may match or exceed the what 150F charge atains. This is not taking into account any combustion dynamics, of which I don’t know enough to talk about. Other than to say hotter charge temps seem to be more prone to knock which kills power and/or engines.

The car companies want higher engine temps and charge temps for efficiency, not peak power. Generally the combustion process is considered adiabatic, but you do have heat loss. The heat loss when looking at the max power case is probably not significant, but when looking at a car that maybe needs 20 to 25 HP to maintain road speed, heat loss will play a role. Being able to increase operating temps, decreases the delta T between the combustion chamber and the coolant, which will retain more heat to drive the engine and increase efficiency at road speed. Very little benefit at the strip though.
 

earlbrown

runs with scissors
I guess the ''but that's another topic for another day went right out the window....

This is not taking into account any combustion dynamics, of which I don’t know enough to talk about. Other than to say hotter charge temps seem to be more prone to knock which kills power and/or engines.



It looks like you glossed over the fact of knock being a binary event. You either have it or you don't. (and the rules change when you get it).


If a hotter intake temp doesn't cause knock, it's really a non event that results in a higher temp in the cylinder.

Now in the case of our engines we have the ability to adjust our max cylinder pressure just by turning a thread. Putting an engine on the ragged edge of knock, then making the mixture more prone to knock is a recipe for disaster.

Then you have the fact that right at 1/3 of the heat generated by burning fuel is wasted out the tail pipe. (the actual reason that turbos are so badass) The other 1/3 heats the coolant. The hotter is it, the smaller the deltaT. .....up until meltdown, of course.



Moral of the story: Colder does not automatically equal better.
 
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