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Let's talk cooling/airflow (simple + radical solutions)


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So basically my plan is thus: Create the most optimal conditions as possible for my intake by maximizing airflow and lowering temperatures, while keeping a close-to-stock-as-possible look. Now I know this has been discussed before, but I was thinking there might be other solutions, or experimental methods.

 

I've spent a considerable amount of time (and money) trying to cool my home PC. I believe that some of the methods involved in that could be applied to cars as well. For example: a set of small electrical fans that blow air directly in to the filter. or: a CPU cooling block attached to the throttle body, circulating coolant through a small aquarium pump and reservoir system. All these would require minimum current to run.

 

Thoughts? Comments?

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But isn't there simply one intake port on an EA82, on top of the TB? Are you saying that one could add an entirely new intake point or that you could have several hoses going towards and terminating at the TB? (and what is ITB?)

 

I also don't understand the coolant line bit...are you suggesting plugging the coolant line into the TB? I thought that one should try to cool all parts of the TB possible? Or is the temperature of the manifold more important?

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I also don't understand the coolant line bit...are you suggesting plugging the coolant line into the TB? I thought that one should try to cool all parts of the TB possible? Or is the temperature of the manifold more important?

 

The coolant is heating the throttle body and manifold, not cooling it. This is simply to ensure proper vapourisation of the fuel in low temperatures, and is generally not necissary at all.

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A cold intake tract is fine with dry flow (i.e. MPFI), but with the SPFI’s wet intake, a cooled tract will cause big problems at lower velocities and in cooler weather, fuel will condense on the walls and cause mixture issues.

 

Best to make sure your “cold air intake” truly is one, like the OEM, drawing air from outside the engine compartment. I don’t like to be a naysayer and I’m all for testing new ideas, but the time, effort and money spent on most gimmicks and tricks would be better spent on real performance enhancements, like over all air/fuel through put.

 

Just my thoughts

Gary

 

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hey i hate to burst your bubble but, cars are built to make their most power with an air intake charge of 120-128 degrees F, if its too cold the atomized fuel will fall out of suspension, and too hot, well less power, so there is a VERY fine line on what you can do. but putting fans in, its just a air restriction, just like taking out your cats, cars are made to work with back pressure, plus the car will run BETTER and have more output power with cats on.

 

so i would say ether turbo the car, or leave the stock air intake alone.

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I've thought of this myself; Butane blowing on the airfilter to superchill it? Maybe get some dry ice involved? Only run the car in Antarctica? I know that we can look at about a 2% bump in horsepower for every ten degrees F below standard temp and pressure the air charge drops. But for the butt-dyno to feel it, you've got to get down to zero temps (No temperature out here at all, folks!) and dry conditions. I think you might be better advised to look at increasing density of the air charge by wringing all the water vapor out of it. Probably easier in the long run, and probably a better overall noticeable gain.

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the only really thing you can do is to put in a resistor in-line with your CTS, to trick the computer to put in more fuel and getting more performance.

 

Shean

 

PS

even if you do ice the intake or anything like that, it will still heat up by the conductivity of the aluminum of the engine.

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More fuel wont help - anything over the stoichiometric ratio (14.7:1 by mass for petrol) will cause the mixture to burn slower, thus decreasing performance. Sometimes it is desireable to run slightly rich to combat detonation and to ensure complete use of the available oxygen, but if this is necissary your computer will already be doing it!

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More fuel wont help - anything over the stoichiometric ratio (14.7:1 by mass for petrol) will cause the mixture to burn slower, thus decreasing performance. Sometimes it is desireable to run slightly rich to combat detonation and to ensure complete use of the available oxygen, but if this is necissary your computer will already be doing it!

 

true, but the o2 sensor and OBD feedback system will take care of this..

 

by the way, the 14.7:1 stoichiometric number is for the highest catalytic converter effeciency.

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by the way, the 14.7:1 stoichiometric number is for the highest catalytic converter effeciency.

 

Its also the correct fuel to air ratio, full stop. Do the chemistry, you'll see.

Any leaner=slower burning, Any richer=slower burning.

Slower burning=bad.

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Shadow ya big show off :lol: Actually that was some good read'n and now my brain hurts. Thanks for posting all that info!

 

Here's my shade tree thoughts on this matter...

 

Puting insulation around an SPFI intake manifold wont yield the efect you want. Youll be trapping heat in from the coolant passage that runs allong the bottom of the intake manifold. Now if you have an intake manifold that has a seperated coolant crossover passage you could insulate properly.

 

If you are hell bent on cooling your intake charge get one of them thar fancy intercoolers. They dont require a turbo; you could plumb one in to your NA air indictuion system. Still wouldn't expect much in the way of realistic power gains.

 

Don't waste your time with minimal gains achieved from a sightly cooler intake charge. Put on some dang forced induction and other real performance modifications.

 

Hopefully I'm not polliferating missinformation here but if I am please correct me Shadow :drunk:

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So basically my plan is thus: Create the most optimal conditions as possible for my intake by maximizing airflow and lowering temperatures, while keeping a close-to-stock-as-possible look. Now I know this has been discussed before, but I was thinking there might be other solutions, or experimental methods.

 

If your car has a snorkel in the fenderwell, like most scoobies seem to have, cut it somewhere inside the fenderwell. Attach some aluminum ducting to it and route the ducting to an opening in the bumper area.

 

This way, you'll keep your stock look, get cooler air and maximize your air velocity depening on how your aluminum ducting is pointed.

 

How do I know? I tested this out on one of my XT6s. I cut the snorkus in the fenderwell and attached aluminum ducting out through the passenger side foglight. It resulted in better throttle response and less downshifting on the highway at certain speeds. Since it was poined out through the foglight, it resulted a leaner air/fuel ratio. Previous to this mod, the air/fuel ratio would almost remain the same despite my going faster and faster. With the aluminum ducting pointing out through the foglight, the air/fuel ratio got leaner and leaner and leaner the faster I went. At I'm-going-to-go-to-jail speeds, I can't imagine how lean it would have gotten. I haven't tested it up to those limits. The affect of the mod was VERY noticable. I posted about it at XT6.net.

 

Another thing! I tested this out at the dragstrip and it resulted in trap speeds increase at the dragstrip by 2-3mph. Before doing the mod, I could not break into the 80mph range. I always ran 78-79mph. After the mod, I did 14 runs back to back, heat soak (if any) and all and just about all of them (except 1 run) were in the 81mph range.

http://www.xt6.net/forum/viewtopic.php?t=1099&highlight=dragstrip

 

Hope this helps!

 

BTW: If you want to go a step further, purchase yourself a 'used' (they are expensive) PRM air filter (like the Cobb air intakes use) and some aluminum piping. My advice is to get piping that is the same size as the throttle body. You could create your own cold air intake and attach it to the stock snorkus and aluminum ducting for added affect. I'll post my setup on my XT6 (since I'm proud of it. I suck at everything else..hehe).

 

mini-000_0004.jpg

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:slobber:

 

Now is that a purely custom job, or are you using part of a kit?

 

Where would you suggest to go to get piping like that cut, and what do you use to combine the different sections of pipe?

 

Phaedras,

 

I replied via PM. I don't know how I missed your questions. :-\

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Myxalplyx, what is the role of the black plastic box in the fender? I'd have taken mine apart to see, but its cover is held on by six screws made of rust.

 

I have the same questions as Phaedras. Could you post the answers here?

 

Another question: is your engine compartment longer because of the H6? Or is your engine just really snug in there?

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Myxalplyx, what is the role of the black plastic box in the fender? I'd have taken mine apart to see, but its cover is held on by six screws made of rust.

 

I have the same questions as Phaedras. Could you post the answers here?

 

Another question: is your engine compartment longer because of the H6? Or is your engine just really snug in there?

 

I'm no expert TheBrian, but I think the black box is there to serve two purposes. One to direct air to the engine that's not as hot as the air inside the engine bay. 2nd, to quiet down the intake noise.

 

If you were to stick a cone air filter on the maf sensor with as little piping from the maf sensor to the throttle body, the intake 'noise' would be louder.

 

I can't tell if it's longer or not. The hood looks longer but when you open the hood, it doesn't seem a whole lot longer. Yes, it has the two extra cylinders but the 4 cylinders have a spare in the engine bay. I can't remember if the 2 extra cylinders were added towards the firewall or towards the radiator.

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