Stock location IC vs FM

[bruce]

Originally posted by mgmshar
In addition, the temperatures of the air entering the throttle body were consistently lower with the FM units.

The only problem is that it's the charge temp going past the intake valve is what counts.
You can play all kinds of stats to show all kinds of results.
When you start measuring temps in the plenum, the pic changes.

You can have uppipe temps in the 70s, and actual MATs, in the plenum, of 130+.

Oddly enough the new Accel Gen VII has picked up on using an actual Manifold temp..

 

[BoostKillsStres]

Just to backup Bruce's interheater vs. intercooler tag I did quite a bit of driving and data logging with the mat sensor in the upper plenum and under steady state driving, in both 50 mph and 70 mph ranges for around 20 mins, on 65 degree days I always saw mat temps in the 95-100 degree range. So that gives an idea how much heat a stock location gets even when the air is cool and your constantly moving at speed. Once coming to a stop at a red light, the temps would rise form there usually into the 105-110 range. This is with cold air pickup, V4 with scoop and the stock crank fan.

Also when rolling into boost the mat temp would normally drop about 7-8 degrees as a large amount of air rushed in then level off for a second then start climbing under boost.

So you figure a FM might have almost a ~28 degree advantage right off the bat and after looking over the Source testing that number even seems consistant for the full boost runs.

Just food for thought.

 

[bruce]

Originally posted by BoostKillsStres
Just to backup Bruce's interheater vs. intercooler tag I did quite a bit of driving and data logging with the mat sensor in the upper plenum and under steady state driving, in both 50 mph and 70 mph ranges for around 20 mins, on 65 degree days I always saw mat temps in the 95-100 degree range. So that gives an idea how much heat a stock location gets even when the air is cool and your constantly moving at speed. Once coming to a stop at a red light, the temps would rise form there usually into the 105-110 range.

I've routinely seen temps at 160dF at drive thurs on a 100dF day.
If you've noticed I've gone to a none air cooled plenum, so my temps do run slightly higher then the norm.

A goggle for negative supercharging is interesting in that they try to deliver 120dF to that engine.

Not to be ignored is that lots of the aromatics of gas start to really vaporize well at 120dF, or so. And making gas most reactible is what it's all about.

 

[mgmshar]

The only problem is that it's the charge temp going past the intake valve is what counts.
You can play all kinds of stats to show all kinds of results.
When you start measuring temps in the plenum, the pic changes.

Maybe I'm missing your point, but...

When everything on the car is staying the same except the intercooler, would there not be good correlation between air temperature entering the throttle body and air temperature going past the intake valves at WOT, assuming boost is constant??? The cooler the air going into the throttle body, the cooler the air will be going past the intake valves, yes? Generally, for a given boost pressure, you want the air to be as cold as possible going into the intake manifold, yes? Per the ideal gas law, colder air at the same pressure equals higher air density.

If all-out performance at WOT is what you are after, then colder air is better. I guess the only exception I can think of is when the air is so cold that the fuel doesn't evaporate properly in the port and cylinder, but that's usually not an issue.

I must be missing your point somewhere...

 

[bruce]

Originally posted by mgmshar
Maybe I'm missing your point, but...
When everything on the car is staying the same except the intercooler, would there not be good correlation between air temperature entering the throttle body and air temperature going past the intake valves at WOT, assuming boost is constant??? The cooler the air going into the throttle body, the cooler the air will be going past the intake valves, yes? Generally, for a given boost pressure, you want the air to be as cold as possible going into the intake manifold, yes? Per the ideal gas law, colder air at the same pressure equals higher air density.

If all-out performance at WOT is what you are after, then colder air is better. I guess the only exception I can think of is when the air is so cold that the fuel doesn't evaporate properly in the port and cylinder, but that's usually not an issue.

Yes, cold is better.
But how much cooler is it where it matters.

If the intake is heating the incoming air to 130, it doesn't matter if the air going into the TB is 70 or 120d. From what I've seen in none boost conditions the MAT lags the coolant temp by 30dF most of the time. Prolonged idle and WOT can drive the MAT higher then that.

Now, if you have a hot intake and it it's say at 130dF, it changes the take over point for when you see any real benefit from the lower pre TB temps..

And your concentrating on just short run WOT. For some folks, it's what's going on after 3+ mins at near WOT that counts.

Just stirring the thought process.

 

[Nojug]

It looks to me that you have a fairly stock motor with bolt ons if you ran 12.30's with 20psi and you want to run mid 11's its gonna take 25-30 psi to get it done, which in turn creates alot of heat, heat=detonation, do we like detonation? Well obviously no so buy a front mount and be done and if you say to yourself in a year I want to run 10's you wont be buying another intercooler, buy it once!

 

[strikeeagle]

Take the stock I/C, and mount it in front of your radiator. Yup, that'll settle the argument for all time...

 

[TWISTER]

Thanks for all the help on this guys the car has more in it with the combo it has but the PTE FM is on sale now and the stock locations that you cant seem to get is almost the same price so $$ isnt the problem its really just the fact of cooling and lag with the D5. I plan on calling Joe Lubrant and talk to him on it but lots of opinions from board members is really appreciated before making the decision. As of now Im leaning toward the FM.

 

[Snorman]

but the PTE FM is on sale now and the stock locations that you cant seem to get is almost the same price so $$ isnt the problem

Exactly.
I'm making big changes to my combo, and I need at least a stretch. The Mease stock location is a beautiful piece, but I can actually now buy a PTE FM for about $100 less than MPE is asking for his stock location kit. I couldn't resist. My PTE should be here tomorrow.
I already have a Micale radiator and dual RC fans, so cooling isn't an issue.
S.

 

[LETHAL-6]

Why dont you talk to some people that run each intercooler on the street that are at the goals you are trying to reach. Im sure that if you want a stock location, some one is willing to help you find one. I don;t think it will be easy to find a V4but, There are the FairPark intercoolers that are made with stock cores they are out of ohio, You can contact Quad Air, or N C Turbo he has posted here on the board his car has one of these intercoolers on it he can give you some feed back. Good luck with which ever choice you make. You can also check with Mease performance Im sure they can build you one and get it to the vendor of your choice.