Intercooler Research
------- Oct. 25, 1996
At 11:34 PM 10/24/96 -0700, you wrote:
>> You could use one from a new TDI Passat, Golf, or Jetaa, they all
>> run around $300, not too bad eh? You could also use an Audi 5000 unit
>> and put it infront of the starter or use a Saab 9000 Turbo intercooler in
>
>> the batter tray like me.
>>
>> Jeff
>
>Hey there Jeff,
> Tell me more about that Saab 9000 intercooler and your car... Is it an
>A-1? Do you have a G-60 or turbo? Also what did you use for tubing?
>Aftermarket tubing or a DIY type thing? Or are you using some kind of
>stock intercooler hoses? Are you getting fresh cold air to it or just
>getting air downwind of the radiator? How do you get the airflow over your
>intercooler in the battery tray location? What about in front of the
>starter motor?
>
>I was thinking it might be cool to make a plumbing system out of plexiglass
>but it might get a bit toasty on the hot side (enough to melt maybe)...
>
>That's neat about the TDI unit being cheap new... I didn't know that -
>It's a good back-up option - I've already got the dealer's computer
>printout of the TDI intercooler and plumbing parts blowup
>I was thinking of checking out the Corrodo G60 intercooler part blowup next
>time I'm down there...
>
>What's the market for a used Audi, Corrodo, or Audi intercooler anyways?
>
>Thanks for seeing my message!
>Jake
>
>
Corrado intercoolers are VERY easy to come by here in Oregon. I
have one myself I don't plan on using and will sell it VERY cheap if you are
interested.
OK, I have a G60 in my car ('83 rabbit GTI). The car isn't done yet
although I have little left to do: wiring, intercooler plumbing and hooking
up the exhaust. As for the plumbing, I know a guy who manages an exhaust
shop. I plan on making models of the hoses out of whatever material I can
get, then I'll take the models into my freind's shop and have him bend 2
1/4" exhuast tubing to match my models. Metal makes good intake tubing,
many manufacturers use it instead of rubber. I/you will however, need to
use a short piece of rubber hose to connect the pipes to the
intercooler;throttlebody;supercharger. Plexiglass would work if you wanted
to use it I guess; don't worry about it melting as the intake temps never
exceed 200degrees or so.
As for air getting to it, I have it placed horizontally on the
battery tray so air needs to come from either below via ducting or above via
a hood scoop. At first, I will have no ducting (I'm in a big hurry), then I
will make some ducting attatched to a 4" 250cfm Jabsco marine squirl cage
blower. This looks like a heater core fan and will suck up air from below
the car and then blow it through the intercooler through the ducting. Also,
if you know you are going to be racing someone, you can make some sort of
container that's open on top and bottom, place it over the intercooler and
fill it with ice. By the time you get lined up to race etc, the ice will
start melting and the cool ice water will chill the intercooler.
As for corrado intercooler prices, most junkyards want $200, but
I'll sell mine for cheaper. Good luck!
Jeff
----- Oct. 30, 1996
>
>Could I fit it in my A-1 or what? I've never studied a Corrodo intercooler
>up close so could you describe it for me?
>
Uh, the thing is rather cube shaped. It's probably 5" thick, 6 or
7" wide, and maybe 9 or 10" tall. The manifolds (hose outlets) are
postitioned oddly due to the placement of the intercooler in the Corrado.
The Corrado intercooler is attached to the bumper support rail below where
the batter sits. You wouldn't have room for it there and besides, no air
could get through it. You could possibly put it on the battery or somewhere
else if there's room.
>Cool. Good guy in the biz to know when you want to add an intercooler.
>Are you gonna go for the whole enchilada and get it in Stainless?
>
No, too hard to come by and SS costs too much. I want to get the
thing done quick. I'm having a hard enough time trying to get him to bend
what I need. As it turns out, the bends I need are hard to do.
>But what about close to the turbo? (I remember seeing a MerKur xr4ti with
>GLOWING RED turbo! Talk about heat! Maybe it's a Ford/MerKur thing...)
>
Yes, turbos glow red hot under normal operating conditions, but
remember, I have a supercharged motor which runs QUITE a bit cooler. With a
turbo, intake temps are very hot and metal tubing is not a luxury.
>Why the Saab and not the Corrodo intercooler?
The SAAB intercooler is shaped quite nice: 2.5" thick, 9"wide and
8"long with both hose outlets pointing the same way: to the supercharger and
throttle body.
>I'm almost turbo-dieseling! (Maybe soon to be intercooled? We'll see...)
Do get an intercooler, you'll see at least a 20% increase in power,
probably more especially at highway speeds. Have fun!
Jeff
------- Nov. 2, 1996
At 05:56 PM 10/30/96 -0800, you wrote:
>Thanks for getting back to me.
>
>Wow that Corrodo intercooler sounds like a real hunk of equipment. I think
>I'll have to do a little research down at the wrecking yard. What's the
>thing made of anyways and what is the inside diameter of the inlets and
>outlets?
>
The intercooler is made of aluminum as most are. The hose
connections are about 2 1/4" I think.
>So it mounts right under the bumper support rail... Are you sure it
>wouldn't fit on an A-1 Rabbit? What does it interfere with? My guess is
>maybe the transmission? I wonder, maybe it just might work. For airflow
>to that area, I have this idea of getting air from behind the bumper though
>a hole I could cut in the body panel. This would be high pressure,
>especially with the front air dam. Too bad I'd have to cut a hole though.
>But you're going though a hole in the hood, that can't be too much
>easier... Plus the hole would be hidden by the bumper.
>
I've held the intercooler under there and it will sort of fit, but
in order to get air to it, you would need to cut a a chunk not only out of
the iar dam but also out of the corner there where the bottom of the core
support connects to the bottom of the fender. I don't like the idea of
cutting that area. It would also need to be mounted under there at somewhat
of an angle to clear the body.
Also, I'm not ducting air for my intercooler through the hood. I
don't want a hood scoop, too tacky and it attracts too much attention. I
will give it air from underneath the car via ducting and a squirl-cage blower.
>Do you really think I can get 20%? In europe the turbo diesel went from 70
>to 80 hp with the intercooler. It would be cool to fit a hulking Corrodo
>intercooler in there and put lots of air to it...
>
The hp figures given are on a dyno with no air cooling the
intercooler, that 10 hp was gained by the intercooler acting as a heat sink,
ie some heat was lost due to the fact that an aluminum intercooler tranfers
heat well. At highway speeds, hp in that car would be more like 90 or 100.
>Also another question (Thanks for answering all these questions, by the
>way): do you know if I'd need to modify the turbo to make use of the
>intercooler? How does that work?
>
The turbo would not need to be modified, only the hoses in order to
get to and from the intercooler.
Jeff
--------- Nov. 4, 1996
At 02:36 PM 11/4/96 -0800, you wrote:
>Hey Jeff
>
>How's the project coming along? Done with the plumbing yet?
>
>So are you going aluminum on the tubes?
>
The project is OK, I got set back a couple of hundred dollars on
maintinence for the car I am driving in the meantime though. The plumbing
is this weeks goal and I will use aluminized exhuast tubing, the exact same
stuff that a muffler shop makes your exhuast out of.
>Have you thought about going around the headlight?
>My TD air intake gets it's air from around the passenger side headlight...
>
Not enough airflow for the intercooler comes from the headlight
area. The intercooler rule of thumb is that if the intercooler is placed in
back of a cars grille and in front of the radiator, it will get 10mph of air
through it when the car is going 60mph. 10 mph of air is the "standard good
efficient" amount of air. Sound dumb? That's really the only way I can
describe it. So anyway, no scoop, especialy a low-profile hood scoop is
going to shove air through the intercooler like it would behind the grille
so why try? The only other way to get around having to mount it in a direct
path of the oncoming air is to mount ducting and a squirlcage blower fan to
it. The fan draws air through the ducting from a cool air source of your
choice (usually under the car), and forces it through the intercooler. The
squrilcage fans are the only fans to use because they have enough power to
force 10mph of air through it, unlike a conventional type fan.
>I guess what I meant here was about the physics of intercoolers. When you
>add an intercooler does your turbo automatically rev higher at giver engine
>RPM and push more air through it? How does the turbo know to do that?
>Also how does the engine get more pressure when there's a wastegate in the
>turbo? Do you have to change your Turbo/Wastegate to get more air/power
>through the engine?
Very good questions, and I have very good answers. OK, the turbo on
your car probably supplies between 6 and 10psi of boost, but is good for
probably about 15 or 20psi of boost; most all turbo cars are that way.
Anyway, the loss through an intercooler is called the pressure drop. By
adding an intercooler, you must add more hose to plumb the thing, those
hoses will have to be bent which also takes pressure away. The rule of
thumb is that the total system: intercooler, and pipes should not exceed
about 2psi total. Each 90 degree bend in piping will drop you about .1 to
.2 psi on a mandrel bent tube, or .3 to .4 psi on a non-mandrel bent or
casted metal elbow. A good intercooler should probably drop around 1psi.
This loss can be made up for by the wastegate. No need to replace, simply
adjust. It should have an adjustment screw on it, a few turns and viola! I
would also recommend turning the boost even higher than it was before
because with the intercooler, it is safe to run more due to the cooler
intake temps.
BTW, if you are interested in spending around $500, you can order a
custom built intercooler of your dreams from a company here in the States.
You can have basically any size and hose outlet configuration you could
imagine, the drawback being the price.
Take it easy and I'd be happy to answer any more questions you might
have!
Jeff
------------ (Oct. 23, 1996)
In message <199611012314.PAA15805@mailhost2.cac.washington.edu>, Jake
Russell writes
>Hi David!
> I've been doing research on intercoolers that I might be able to find
>used
>- here's what I've come up with so far:
>
>Saab 900: 9" wide, 2.5" thick, 8" tall - inlet & outlet at same side
> = 180 in^2
>
>Corrodo G60: 9.5" wide, 5" thick, 7" tall
> = 332.5 in^2
>
>Audi 5000: 12" wide, 3.5" thick, 4" tall - inlet & outlet at opposite sides
> = 168 in^2
>
>Could you do me a big favor and supply me with the VW GTD intercooler
>specs?
>I've found a good deal on the Audi maybe that's what I'll go for if it
>fits...
>
>Oh by the way did you get my response to your badge supply offer?
Reply to badge request already sent.
A2 GTD intercooler is 11.5" wide, 2.5" thick and 9" tall. The part
number is 191 145 805A and it is manufactured by Langerer and Reich.
Hope this helps.