carrera style badge panel

[CarreraRSR]

ORIGINAL: TTM

I don't think the vents on the original 924 panel were even actually functional?

My 924 turbo 'work in progress' to see under the usually welded on badge panel. Rare bolt on waiting above. Improved air into the rad/engine bay from under the badge panel as well.

Even if a 924 turbo badge panel was used with 944 turbo FMIC, my guess is as long as the duct from the bumper slit remains in place then the front face of the IC will still receive the correct dose of cool air in volume and air speed, yes??

Based on this I am considering using the 944 turbo duct from a slit in my 924 bumper to feed the FMIC install I have done. The air from the four grilles will just pass around the duct, help with alleviating heat soak of the IC perimeter. Any thoughts?

We ended up cutting off the whole 924 front section and welding a 944 version. 951 IC now sits perfectly in place

Any one have a 951 FMIC bumper duct??

 

[TTM]

You will have to modify the 951 intercooler duct as the opening will obviously lead to behind your front bumper.

ETA : I can't stop drooling over pics of your car [8D]

 

[CarreraRSR]

ORIGINAL: TTM

You will have to modify the 951 intercooler duct as the opening will obviously lead to behind your front bumper.

ETA : I can't stop drooling over pics of your car [8D]

The potential plan is to move the number plate down a touch or to the badge panel/bonnet. Then create the slit required in the front bumper equal to a 951's and therefore minimal adjustment of the air duct to suit the FMIC.

Still need a duct please!

 

[944 man]

How are you going to make the opening Steve? The bumpers are made of a horrible compressed fibre material and you could wear out 3x Dremels and it still wouldnt look quite right.

Its a shame that you cant get a trim panel to dress it. Perhaps the solution might be to buy a damaged old 951 style PU and cut out the inlet eare and graft this onto you existing bumper. Thisll allow a tidy finish to a rougher hole and itll help you to mount the registeration plate properly too.

 

[CarreraRSR]

ORIGINAL: 944 man

How are you going to make the opening Steve? The bumpers are made of a horrible compressed fibre material and you could wear out 3x Dremels and it still wouldnt look quite right.

Its a shame that you cant get a trim panel to dress it. Perhaps the solution might be to buy a damaged old 951 style PU and cut out the inlet eare and graft this onto you existing bumper. Thisll allow a tidy finish to a rougher hole and itll help you to mount the registeration plate properly too.

I did post somewhere I was looking for a damaged front PU and duct. May have been here months ago. So yes you are right, having some of the 951 parts will allow me to maintain an OEM look and feel plus it all should just work!

 

[George Elliott]

I know this will depend on compressor efficiency and on the location of the cone filter, but how would you rate an intercooler set up that makes for intake air temps that do not exceed ambiant air temp by more than 25°C?

Pretty good in my opinion.

If an engine that is working hard with maybe a dull red hotside (say 700degC) intermittently, but can hold intake air to within 25 deg of ambient, then the IC must be doing a good job.[]

IMO
George
944t

 

[944 man]

ORIGINAL: CarreraRSR

ORIGINAL: 944 man

How are you going to make the opening Steve? The bumpers are made of a horrible compressed fibre material and you could wear out 3x Dremels and it still wouldnt look quite right.

Its a shame that you cant get a trim panel to dress it. Perhaps the solution might be to buy a damaged old 951 style PU and cut out the inlet eare and graft this onto you existing bumper. Thisll allow a tidy finish to a rougher hole and itll help you to mount the registeration plate properly too.

I did post somewhere I was looking for a damaged front PU and duct. May have been here months ago. So yes you are right, having some of the 951 parts will allow me to maintain an OEM look and feel plus it all should just work!

Using an original PU section will help you to fit the shroud too, Id expect, providing that youre able to mount it in the correct location.

 

[944Turbo]

On the plastic section that leads from the front of the car to the IC I always taped up the slits and sealed it to the Intercooler so the air couldn't take the easy route out and had to pass through the IC. Didn't take any readings but didn't seem to do any harm

 

[Indi9xx]

If I was CarreraRSR I would probably look at making an inverted version of the 944turbo plastic cowl to match up to his nose vents and not going for anything to do with the standard 944 turbo cowl or PU

The 924 turbo will see much lower potential road and air speeds.

I would recommend fabricating his cowl from thin guage aluminium and attaching it to the intercooler firmly, ideally welded, as it will also then add to the heat soak thermal aspect of the intercooler and give him more capacity for soak, as well as increasing its surface area for cooling.

With a bit of thought, he could make this very well, within his badge panel and snugly fitting his badge pannel with draft excluder to encorage flow forced through the intercooler.

Likewise, for use at lower potential speeds than a 944 turbo can perfrom at, such as a 944 turbo with a hybrid S2 LSD box, I would say again you can increase the opening size for use with standard intercoolers or ones based on the standard intercooler (such as the LR and 9XX ones)

Big front mount intercoolers for other Marques tend to be designed for potentially lower top speeds (such as 140 to 150 mph with cosworth, suberu, evo's) or have wider spacing of their cooling fins to allow high speed airflow without turbulance and vortexing blocking the cooling airflow.

 

[944 man]

So, the extra vents found in some aftermarket badge panels only cause an airflow problem at speeds double our speed limit, or have I misunderstood you?

 

[Indi9xx]

The standard core in a 944 Turbo intercooler has fin spacing that is honed to a maximum airspeed (not roadspeed) of cooling air, if the cooling air moving through the intercooler exceeds this speed, it becomes less and less efficient and the resistance to the cooling air increases as does the flow of the cooling air.

Make the vents bigger, the closer the cooling air airspeed becomes to the roadspeed.

It may not seem important, you could open the front right up and never have a problem... Until one day you are traveling on an autobahn as a one off trip to the Porsche museum, with your engine tuned for detonation which will never happen at lower roadspeeds, and without you knowing it your intercooler will become heat soaked and your intake charge temperatures will go up and up until the detonation threshold it reached and boom.

It need not even be the autobahn, maybe it will be 5am on an empty motorway and the animal within puts caution to the wind, you fancy a taste of 150 mph following a year of frequent brief 130 mph stints and again... Boom.

A good intercooler would be designed to match not only the turbo and intake charge it is trying to deal with, but also road/air speeds it will be presented with. The 944 turbo intercooler was designed to work at a airspeed that was reduced by the cowling to be a fraction of the roadspeed. Which is also why the 944 turbo intercooler is so deep, lower airspeed combined with leaving the cooling air in contact with the intercooler for longer by having it also deeper than most.

Some more experimentation could find the ultimate airspeed for the 944 turbo core, at which speed exactly it begins to hamper efficiency and therefore the volume of air in a given amount of time.. From that, the size of the feed could be honed for different applications and roadspeeds.

One could say "Well I never intend on going above 120mph"... for those people I would say consider a different mod which will allow you to run bigger venting to the intercooler and gain you far more accelloration than any other mod you will ever do... change the transmission to one lower geared for your application. []

 

[TTM]

I happen to be a regular user of the Autobahn going to Stuttgart from Kehl and with my "brick" intercooler (SFR) in front of the rad with special ducting I never see IATs higher than 25°C above ambiant air temp.

As you said earlier by the time you reach 150 mph + speeds you won't need much boost if any to maintain that sort of speed, so IC performance may not be relevant there, and in my case it would appear that speed builds faster than the heat soak though the IC core.

 

[PSH]

BTW Jon, your inbox is full....

Pete

 

[Indi9xx]

What size is your engine TTM?

And is yours the SFR Stage two intercooler?

And lastly, where are you taking your temperatures from?

 

[TTM]

3.0
SFR Stage 2
IAT sensor on the intake manifold, right after the throttle body.

 

[Indi9xx]

My comments regarding badge pannel modification and airspeeds are more relative to intercoolers using the standard 944 turbo intercooler core. such as of course the standard intercooler, the LR intercooler and the 9XX intercooler.

The SFR stage two has a more conventional front mounted intercooler design, with I believe, wider fin spacing and is not as deep as the standard core. so can probably deal with higher airspeeds than standard cores. I have handled a couple of SFR-S2's, but not since I started evaluating the standard cores with such scrutiny to cooling airspeeds and the relationships to roadspeeds with ducting.

Also, as engine capacity increases (as with efficiency increases) the requirement of boost to produce the power to maintain a constant speed decreases, so a 3.0 Turbo will require less boost to maintain 150 mph than say a 2.5 engine. Less boost will generate less heat for the charge.

It would be interesting to experiment with the SFR cores as well, another thing to add to the to-do list.

 

[TTM]

Yes, fin spacing is wider. SFR use a Turbonetics core in their Stage 2 kit. At least they did in mine.

 

[Indi9xx]

Looks like a good product from your findings.

And by the sounds of it, one that can deal with a close air to road speed ratio.

I might have to get another one in to experiment with, would be nice to figure out its heat soak parameters, but I could probably work that out from its weight and assume to alloy specification.

One experiment I would also like to run would be its absorbsion rate at a standstill from the radiator to understand its launch implications. Have you noticed any intake temperature increases when sat in traffic?

 

[TTM]

When sat in traffic I have not noticed any difference. The fans are apparently still able to extract as much heat as needed on their own when they kick in, at the same rate as they would on a standard set up, as I see coolant temp on the gauge go back to its "normal" position just as quickly.
That said, I took off the resistor pack for the low speed of the fans and shorted the wires, meaning that the fans will run in high speed as soon as reaching 92°C as triggered by the standard fan temp switch.

I did notice a difference when driving at slow speeds. Coolant temp would rise a bit more quickly, though this was more observable in very hot weather like last Summer and now that the weather is cooler, it's less of a concern.
The first step that helped significantly with keeping coolant temp down at moderate speeds was to keep using the opening in the front bumper for the standard intercooler, make some ducting to force the air flowing through to the upper area of the radiator and close any area so that air doesn't flow around the radiator. For instance I flipped upside down and adapted the plastic sheet that originally sits between the standard IC and the radiator. Consequently, it helped reduce coolant temp even more quickly when accelerating to higher speeds.
The second step was to add an horizontal sheet of aluminium between the intercooler core and the radiator so that the air flow coming from above would not interfere with the airflow coming out behind the intercooler to the radiator and possibly reduce the intercooler's performance.

Note : the A/C condenser is long gone too.

Latest tests consisted of spirited driving on secondary country roads, WOT runs through 2nd/3rd/4th gears, and with an ambiant temp of about 17°C the logs showed a maximum IAT of 40°C. Running 1.2 bar.

 

[PSH]

Very interesting these last few posts, more so since I still need to decide on the best IC for me and the SFR stage 2 is currently top of the list, keep the info coming guys..

Pete