Intercooler design in MSP

[AndrewF150]

just a quick question....

Has anyone on the forum gotten the turbo upgrade from spool? If they have, whats your oppinion on it.

Oh, a second question...would the turbo upgrade from spool void the warrenty of the car? I was told by the dealership that as long as you dont mess with the drive train or any other internal parts that it wouldnt...so you could add exhaust intakes, things of that nature to a new car and not void warrenty...so does that rule aply to the turbo upgrade?

 

[YuYuRena]

so do you mean to tell me that when your not boostin' (and you have a larger volume intercooler) that your boost threshold will go up???
not to flame you here but you need to clarify

What I meant by that is since there's more volume for the air to fill, that the charge mass takes a little bit longer before arriving at the cylinders. This is perceive as increase in the boost threshold. The turbo needs to be pumping more air and thus the engine would be running at a higher rpm to get boost. Air will fill up all the volume between the compressor discharge to the cylinders, as it travels thru the piping. If there's more volume to fill, then boost will be slower to arrive at the cylinders and the driver would perceive that the power is made later.

What I'm saying is basically to calculate your flow rate of your engine to know the flow requirement and then pick a correct size, so you get minimize boost loss and better boost response. Moral of the story is bigger isn't always better.

 

[perfworks]

What I meant by that is since there's more volume for the air to fill, that the charge mass takes a little bit longer before arriving at the cylinders. This is perceive as increase in the boost threshold. The turbo needs to be pumping more air and thus the engine would be running at a higher rpm to get boost. Air will fill up all the volume between the compressor discharge to the cylinders, as it travels thru the piping. If there's more volume to fill, then boost will be slower to arrive at the cylinders and the driver would perceive that the power is made later.

What I'm saying is basically to calculate your flow rate of your engine to know the flow requirement and then pick a correct size, so you get minimize boost loss and better boost response. Moral of the story is bigger isn't always better.

if you were talking about a liquid i would agree. but because there isnt a vacuum created in your intake tubing that theory is wrong . sorry. but the there still is atmospheric pressure in the intake piping allowing you to run N/A under no load.
in other words there is no delay
i can put an intercooler three times the size of the original unit and not have any change in boost threshold ( ie turbo lag).
turbo lag is dependent on inertial loads onto the turbine wheel , not the compressor side.

 

[perfworks]

oh yeah dont confuse anything im saying with pressure DROP across the intercooler and intake track

 

[perfworks]

What I'm saying is basically to calculate your flow rate of your engine to know the flow requirement and then pick a correct size, so you get minimize boost loss and better boost response. Moral of the story is bigger isn't always better.

for an intercooler that statement also is not complete.
every application varies. placement of the intercooler, surface area, flow thru the cooler, top to bottom or side to side inlet and outlet. many things can alter your efficiency.
for intercoolers you need to find the best spot to mount it according to the AVAILABILITY OF AMBIENT AIR FLOW .

 

[Turbo Matty P]

I had spent some time testing the stock intercooler in a "front-mount" location and got some nice gains on the freeway. The car pulled like hell and never seemed to run flat like most hot turbo's. However I believe my new intercooler kit should fix the main problem we have with our intercoolers.....plastic! I'm using a custom built unit that we originally designed for use on my buddys CBR 1100 drag bike. With a little tweaking it mounts right up into the stock location but has a core thats 50% thicker. As I mentioned in another post, this should've given back almost 2psi. Our factory intercoolers just weren't designed for what we're using them for. A little thicker, better made intercooler will go a long way to cooling that intake charge. Also, I'm looking into replacing the second fan with a smaller, higher powered unit that would mount directly to the intercooler and could be turned on and off via a switch mounted inside the passeneger compartment. Anyone interested in this intercooler can contact me through PM or email to SVTMATTY@BELLSOUTH.NET

 

[Turbo Matty P]

P.s. go take a look at Nitrous Express' website. They have a great "N-Ter Cooler" system for freezing the intercooler with N20 or CO2. They claim the N20 blast comes out at -125*. That's pretty good, but I kinda doubt it. I could open my bottle on my wet finger and it wouldn't freeze, just be real cold. Still they claim gains of 52whp on a 1.6L civic running 6psi. Imagine what it'll do for our cars running 10psi??

 

[Option]

if you were talking about a liquid i would agree. but because there isnt a vacuum created in your intake tubing that theory is wrong . sorry. but the there still is atmospheric pressure in the intake piping allowing you to run N/A under no load.
in other words there is no delay
i can put an intercooler three times the size of the original unit and not have any change in boost threshold ( ie turbo lag).
turbo lag is dependent on inertial loads onto the turbine wheel , not the compressor side.

While YuyuRena isn't exactly technically correct is point is valid. By increasing the intercooler size you are increasing the volume of air that the turbo has to pressurize. Imagine if you had a mile of intake piping between the turbo and the engine intake manifold. It would take a LOT longer for the turbo to increase the pressure in all that piping. (thats why many WRX owners don't like upgrading to frontmount intercoolers -increases the length of piping between the turbo and throttle body). Increasing the intercooler size does the exact same thing.

 

[Turbo Matty P]

Option: on the fmic I've been working on we haven't noticed a bit of boostlag. I've seen full boost as early 2800rpms and as late as 3500. But it's consistant, always within that range. I think a larger fmic would be for someone who is planning on running "high boost" (12-19psi). The stock location with a specially designed cooling fan or N20 sprayer should be more than enough for the 10psirange.

 

[perfworks]

While YuyuRena isn't exactly technically correct is point is valid. By increasing the intercooler size you are increasing the volume of air that the turbo has to pressurize. Imagine if you had a mile of intake piping between the turbo and the engine intake manifold. It would take a LOT longer for the turbo to increase the pressure in all that piping. (thats why many WRX owners don't like upgrading to frontmount intercoolers -increases the length of piping between the turbo and throttle body). Increasing the intercooler size does the exact same thing.

THERE is no delay in boost, if the pressure drop , or resitance to airflow is the same or better.
Im not trying to sound like a dick but please read my post(s) carefully and distinguish between what im saying.
There is a reason i posted about equal diameter piping and keeping velocity thru the system, whuile upgrading your cooling efficiency.
I did post however that PRESSURE drop in the intercooler core can cause less boost at the same rpm. But dont confuse that with the current statements that a larger intercooler will cause you to have longer turbo lag.
Turbo Lag is referenced from the turbine NOT the compressor side.

 

[Option]

THERE is no delay in boost, if the pressure drop , or resitance to airflow is the same or better.
Im not trying to sound like a dick but please read my post(s) carefully and distinguish between what im saying.
There is a reason i posted about equal diameter piping and keeping velocity thru the system, whuile upgrading your cooling efficiency.
I did post however that PRESSURE drop in the intercooler core can cause less boost at the same rpm. But dont confuse that with the current statements that a larger intercooler will cause you to have longer turbo lag.
Turbo Lag is referenced from the turbine NOT the compressor side.

Why don't you read my post carefully. I never said anything about turbo lag as I am aware of the true definition of the term. I also never said anything about a "delay" in boost. We are talking about two different things. What I am refering to is a loss in...forget it...I don't care. I'm not wasting my time since the only way I can prove my point is to break out the equations which I don't have time to do right now.

 

[Turbo Matty P]

OK!! So who's up for a new intercooler!! Yeah! (tyring to get back on topic a little)