EBay Cold Air Intakes Any Good??

[Cadillac Jim]

3 hours ago, caddylovermarco said:

I built a cold air set-up that still draws from the hole where the pcm rests (it is a sealed box inclosure around the new cone filter) and have about 90 dollars invested. it took 3 days of testing and fitting to get it to work properly and the box to seal to my high standards and in the end I got 3hp on the dino with little to no torque, so it really wasn't worth it (it was a pain in the blank to get everything to pit proporly) but it does make what people would call a "cool" sound. to sum it up just run the factory set up with a good high quality filter. my new set-up does use bigger 4 inch intake tubing with a spectre cone filter thats about 10 inches long, the tubing I used is welded alumium (I'm sure I butchered the spelling on that) (the tubing is insolated to help with heat), I used welded because the mandral belt tube I got which I'm not including in price because I didn't use it (it was EXPENSIVE) it didn't want to fit because it was to long on the bend. But with my custom magnaflow exaust (which makes it sound better than most mustangs and camaros), custom built engine cover, and front slotted rotors (which were a dealer add on from GM performance which I think is pretty cool) and the few other little goodies on my 99 Eldorado I can impress a few people and get some enjoyment out of it which is all that I care about. and one last thing I did for this set-up (execpt I did it on my 98 Deville) was cut the factory tube and use that instead of the 4 inch aftermarket one because there is more room to get it put on the MAF sensor housing but in the Deville I found there is slightly less engine room so I had to make a different box inclosure and only use a 8 inch long cone filter, for the Deville I there was not hardely a hp boost so it was really not worth it, I just did it because I had a spare tube laying around with my bunch of extra parts. So again I just recomend running the factory set-up with a high quality paper filter (I prefer wix or if you want the oiled spectre ones are a good value if you really don't want a paper one) because on the Deville there really was no performance increase and on the Eldorado there was one but it wasn't worth the time and money I put into it because I can't stress enough how much of a pain it was to get everything to fit and work properly.

See my post, two previous to yours, dated June 28, 2010; I cited a study that Bruce did with a new STS on a 1996 STS when it was new, using performance meters and measured distances with recorded temperature and humidity.  The drupal.caddyinfo link seems to be dead now (I get a message "Unable to connect to database server"); Bruce may know a good link for that page.  Upshot is that "cold air" intakes that did away with the stock air box, which is a factory cold air intake system, actually hurt performance, apparently because they use a lot of hot underhood air.  Cheaper K&N and other low cost aftermarket filters don't clean the air as well either.  Nothing outperformed the stock airbox with a new, clean AC/Delco air filter, and nothing cleaned the air better either.

Another issue that may or may not be important to you is hydrolock when driving through deep puddles.  Water can splash into the air box in sufficient quantity to cause hydrolock.  A combustion chamber is typically something like 65cc or four cubic inches, so it doesn't take much water to hydrolock an engine.  The stock AC/Delco air cleaner is reinforced with a steel mesh that will hold and choke the engine if the air cleaner is totally wet and water clogged.  Another brand of air cleaner, with or without a steel mesh behind the paper element, may give way and let bulk water into the intake.  This is a known problem with some GM pickups using the LS V8 engines but hydrolock can happen to anyone who simply removes the air cleaner element and drives through standing water.

[caddylovermarco]

Did you not read a word I said, I'm agreeing that the stock set-up is the best and the one I made has a box inclosure around the cone filter that only gets air from the factory hole where the pcm is. But yes on the dyno I seen on the Eldorodo at least a very minor 3HP gain with nothing on the Deville. I think a good experiment for me would be to use the stock air box but use the bigger 4 inch piping off of my custom set-up to see if the bigger piping is the cause of the extra 3HP because on the deville I used stock piping and saw no increase. I think the stock piping is somewhere inbetween 3.5 and 4 inch. Also sorry for editing so much I have a bad habit of proof reading after posting.

Edited August 22, 2020 by caddylovermarco

[BodybyFisher]

Explain how the before and after Eldorado dyno testing was done.  

Questions:

Was the test done the same day?, if not how time between the tests?

Was the ambient temp the same on both tests?

What were the HP numbers for each run?, for each vehicle?

Were both cars base engines?

Thanks

[Cadillac Jim]

I'm inclined to believe that you won't see much change by using a different air hose between the air cleaner and the throttle body.  Just using a smooth bore there, changes in the air flow for different RPM ranges at full throttle, etc. will give you small changes everywhere, but 2 Hp is going to be in the range of run-to-run variation with no changes whatsoever.  If you want a change, look at the whole air flow path:  grille-to-air-passage, air passage to air cleaner box, air cleaner box to throttle body (your change is here), throttle body, intake manifold, valves, and ports.  Unless the one you are changing is the biggest choke point, you won't see much improvement.  Often the choke point is the throttle body, but without measuring the air pressure and temperature at each point in the air flow path during a full-throttle run then you are guessing.

Most re-tunes of HP engines begin with a larger throttle body, larger fuel injectors, and improved cooling.  You need an engine analyzer package that lets you look at the spark map and the mixture during a run.  The mixture is very important because if you improve breathing to get better torque/horsepower then you are asking more of the injectors.  If the injectors max out, you will run lean at full throttle, which is a recipe for engine damage.

[caddylovermarco]

The dyno testing was done on a rolling road type machine and was done with about an hour inbetween tests, the temp dropped about a degree outside and the big door to the shop was open so the small change could of affected the dyno. I do have a very nice snap-on scanner/codereader to see all data from the engine sensors and I can tell you that at WOT the vehicle without any modifications to the PCM did run slightly leaner than factory but still in the safe range. And still what part of "I RECOMEND THE FACTORY SET-UP" don't any of you understand, I've already put the factory airbox back in the Deville (havent done it yet in the Eldorado but  probably will). Finally to answer any other questions no I don't remember what the exact temps were but do remember the 1 degree drop after the hour of switching set-ups, the Eldorado is a modded L37 and the Deville is a modded LD8, and is it not perceivable to you that someone can get a small horsepower increase in a different testing inviroment than you.

[BodybyFisher]

On 8/29/2020 at 10:19 AM, caddylovermarco said:

The dyno testing was done on a rolling road type machine and was done with about an hour inbetween tests, the temp dropped about a degree outside and the big door to the shop was open so the small change could of affected the dyno. I do have a very nice snap-on scanner/codereader to see all data from the engine sensors and I can tell you that at WOT the vehicle without any modifications to the PCM did run slightly leaner than factory but still in the safe range. And still what part of "I RECOMEND THE FACTORY SET-UP" don't any of you understand, I've already put the factory airbox back in the Deville (havent done it yet in the Eldorado but  probably will). Finally to answer any other questions no I don't remember what the exact temps were but do remember the 1 degree drop after the hour of switching set-ups, the Eldorado is a modded L37 and the Deville is a modded LD8, and is it not perceivable to you that someone can get a small horsepower increase in a different testing inviroment than you.

"Don't ANY of you understand?"

Are you including me in that statement?

I said NOTHING about what you did, all I did was ask a few questions looking to understand your process

Please do not generalize.

@caddylovermarco

[caddylovermarco]

Sorry about that I did not mean to attack anyone I just didn't think I was getting my point accros that I recomend the factory set-up.

[Cadillac Jim]

The only upgrades that I've seen of late model high performance intakes involves enhancing the factory setup, not replacing it.  The GM setup on the E/K platform has the added complications of routing the air over the PCM to cool it, and having the IAT 1 sensor on the output of the air box.  The whole path involves the air path behind the grille (usually the lower or under-the-bumper part, if the grille is split) to an air box, then through ducting to the throttle body.  An air cleaner element is incorporated into the air box in a manner determined by the designer.  For street or heavy rain use, the air cleaner must incorporate mechanical support to avoid tearing if it gets wet and clogged, which would then let liquid water into the ducting to the throttle body.

Design of such a system ideally takes place with a mule on a dyno, with inspection of the entire torque/hp vs. RPM curve for each configuration tested.  In some cases, changes in the rest of the engine tune accompany this design.  In something like a GM engine development lab, this "tuning" process can include cam changes, value and port changes, spark plug position changes, etc.

[BodybyFisher]

20 hours ago, caddylovermarco said:

Sorry about that I did not mean to attack anyone I just didn't think I was getting my point accros that I recomend the factory set-up.

@caddylovermarco

We used to have an engineer on the Northstar and 4.9 design teams here and he said the same thing, the induction system is capable of so much more output.  What he did say was a problem was the bottleneck of the front exhaust to the Y pipe, he liked the OEM headers but disliked the way the front was run to the y-pipe and y-pipe and he though power could be found there.  The existing setup was a compromise they couldn't resolve in the transverse orientation 

We had a member Mark who turbocharged his STS, and if I recall he ran the front exhaust under the engine carriage

[Cadillac Jim]

Specifically, the worst bottleneck is the front exhaust header, which goes between the rear of the engine and the transmission, if I recall correctly.

Mark had some tremendous numbers from his turbocharged STS for a few months. But his transmission turned to mush before he got one built for the extra 200+ horsepower.  I don't think we've heard from him since.

My favorite source for Northstar ports, cams, valve train, etc. was chrfab.com, which shut down a couple of years ago.  I researched them and find that the key guy was a professional metallurgist who did precision welding on the side, and was the proprietor of chrfab, which specialized in Nortstar sand cars (!!!).  He built one naturally aspirated Northstar that was campaigned in Europe in a Corvette at one time.

[BodybyFisher]

I speak to Mark on and off, he was racing a CTS-V for a while.  Ill post a link to his YouTube vids