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Petrovich · Joined: 27 Sep 2005 Posts: 235 Location: Rockville, MD

Well, I looked at 931's turbo-to-manifold pipe. I then looked at the tight engine bay. I then looked at how bad my Legacy's top mount intercooler is at low speeds. I then looked at how Lotus did their uber chargecooler on the Esprit... And then I looked at the Sentra AC system bits I have

How many people would be prepared to cough up 500-600$ for a chargecooler kit for 931?...
Basically, the theory here is to cool incoming air by a compact air-to-water heat exchanger [aka AC evaporator encased in an aluminum or fiberglass shell] located where your current turbo-to-manifold pipe is, and then to cool the air in a small front-mounted radiator [aka half of an AC condenser for a narrow and long, or heater core for a short and square radiator]. All powered with a 12v water pump, boosted by a second one at full throttle. Seems like a nice solution to me.
The practice is, I have the resources to build these in decent volumes, but unless somebody else wants it, I'm unlikely to have the motivation to try

flosho · Posted: Wed Oct 19, 2005 5:23 am Post subject:

hmm, if you build one and prove it works, id throw down the cash by spring time.

otherwise, i'll volunteer to be a test monkey for a discounted price..

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Kenodog · Joined: 25 Jun 2003 Posts: 2669 Location: Vancouver,B.C.

I have already done what you are proposing and it cost me a whole grand,not half and I payed a machinist buddy and a welder buddy much less than the jobs were worth if you just walked in off the street.By the time you get a decent size heat exchanger ,$200.Jabsco centri-puppy 12v pump,$140.Spearco b-252 air/water intercooler,used,$340.Then you have to move the battery to the spare tire well and run all associated wires,not much money but VERY time consuming.A custom fabricated expansion tank to sit atop the 12v pump which is mounted via custom spun legs,$100.All of the 2" & 2 1/2" aluminum tubing,$40.Being able to use a chop saw to cut the aluminum into various compound angles,10 hours labour.Cost to pay a welder to tig up the 15 or so seperate pcs. into the 5 main sections needed to get around the engine bay,$100.This isn't including paying a machininst to fabricate the needed bosses to be welded to the new charge tubes for the vacuum and boost switches,wastegate line ,etc.Probably looking at another $150 or so for that.5 silicone conectors at $25 each and two silicone reducer couplings at $45 each.And that only works if you have a series II TB to mate up to.Renting the 90 degree drill and the purchase cost of a 2 3/4" hole saw to cut holes in the firewall to run the chargetubes thru,$65.Then there is the actual heater hose,misc. fittings and 2 stainless T-bolt clamps for each of the 7 silicone boots,$7 each X 14 pcs. plus tax on the whole works.Then there are the constant trips to Home Depot or whatever hardware store you use for all of those little nickel and dime items you'll find yourself needing.
I guess what i'm trying to say is that unless you are a very hands on person with ALOT of free time this is a very big undertaking."Bolt-on" as a term doesn't really apply.However,all that being said,the final outcome is nothing less than stunning.I have no doubts whatsoever that I have the fastest 931 in Western Canada if not all of Canada and I could beat any stock 944 with ease at 9 psi of boost,let alone 14 psi which is my go-fast setting on the boost controller.

So if you can do one for $500 as a complete kit- i'll take 2.
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1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

My924gtc · Joined: 14 Aug 2004 Posts: 1362 Location: 248

Paul · Posted: Mon Oct 24, 2005 7:47 am Post subject:

I was surprised to see the battery in an Australian 944 was in the passenger's side rear fender well. The owner said it was the stock location on right hand drive cars.

BTW I am interested in a intercooler kit for $500.
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ESC944 · Joined: 21 May 2004 Posts: 747 Location: FL

Sounds pretty good to me... I cant really say how much I have spent on similar systems over the years. But I can tell you the results are well worth it!

Many are the ways you can cool a charge, this happens to be one of the better ones.

While I tend to do my own thing, I would welcome these, especially as an addition to my supercharger kits.

So build one show it works and I will be glad to talk quantity with you.

Kenodog · Joined: 25 Jun 2003 Posts: 2669 Location: Vancouver,B.C.

I would have no problem with disassembling mine and copying it.The charge tubes would be the most time consuming by far.In fact they represent about 90% of the headache of doing this.Everything else is just time consuming elbow grease.And,you would have to drill the holes in the firewall yourself,relocate the battery and have a series II throttle body or else install one youself.

A kit would come with:

1 air/water i/c from Spearco (B-252 core)
1 Jabsco Centri-Puppy 12v pump
1 custom made set of posts to mount the pump
1 custom made expansion tank for the engine coolant system
1 custom made expansion tank for the i/c
1 set of custom made charge tubes w/vac. & boost take-offs
1 set of Spearco silicone connectors and reducers (6 total)
1 aluminum heat exchanger,size would depend on if you still have AC or
not.

You would be responsible for cutting holes in firewall,moving battery to rear of car,all necessary wiring and fuses for the pump and puting the whole thing together and installing the plumbing.

Keep in mind that even if I charged a grand for all of the above I would still only be making about $50 per kit so if anyone has connections for anything listed above and can get wholesale prices let me know.
_________________
1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

Kenodog · Joined: 25 Jun 2003 Posts: 2669 Location: Vancouver,B.C.

And if anyone else is interested I may be parting out my car if I can't sell it as a whole.The whole system described above for $1000.
I would make a video instructing how everything fits onto the car by showing you me removing the sytem from my car.

Guaranteed to put a big ass smile on the most surly mug.
_________________
1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

My924gtc · Joined: 14 Aug 2004 Posts: 1362 Location: 248

Kenodog IMHO if your system were done with mandrel bends it would be much more appealing. Not a fan of the jagged pipe work. Would you do it different if your were to replicate it?

Kenodog · Joined: 25 Jun 2003 Posts: 2669 Location: Vancouver,B.C.

Nope.

#1-Post welding all of the pieces were de-burred on the I/D seams using a Dremel tool so there are no ridges,weld build-ups etc.,smooth like butta'.
***The trick is to always use the exact same angle for both sides of a joint.***
#2-By making the small,individual pcs. I was able to get around the relatively tight engine compartment and still maintain maximun tube diameter.
And more importantly I can now copy the angles and replicate them en masse,mark directions on them and YOU can weld them yourself.Handy that.

#3-I don't see a huge difference in the way air would flow thru the
tubing.The difference would be minimal at best and you would still need a certain amount of the silicone couplings to give the whole mess a little "flex".
I think the average Joe could not tell the difference between the two.

I had access to a lathe and a welder so that's the road I traveled.

It's hard to express to you how much this has done to actually make the power this car deserves.I can only imagine what this car would do if it had EFI. ,,,,,,,drool,,,,,,,,
_________________
1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

Petrovich · Joined: 27 Sep 2005 Posts: 235 Location: Rockville, MD

OMG
This sounds like a dare.
Kenodog, how big is your heat exchanger? do you have a picture?... Not the assembled one in a box, but just the "radiator" unit itself.

Kenodog · Joined: 25 Jun 2003 Posts: 2669 Location: Vancouver,B.C.

I am currently using a NOS A/C condenser.If I were to keep the car however I would have an aluminum one made up.I already got a quote of $325 Cdn. for it.
_________________
1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

Petrovich · Joined: 27 Sep 2005 Posts: 235 Location: Rockville, MD

Condenser or evaporator? I meant a heat exchanger for the intake, as in, the chargecooler itself. The radiator for the chargecooler is the easy part, I think anything from condensers to heater cores to oil coolers to even small radiators works here, as long as the size is right...
IIRC in Esprit, they went for evaporator as a chargecooler and a half of a condenser for the radiator. I wonder if a heater core is enough to be used as a chargecooler on 931 - it would certainly fit the cramped engine compartment waaaay better than the "almost cubic" evaporator. In fact, a 3-pass setup made from a stock Sentra heater core would fit quite well and require no modifications - it would look pretty much the same as a GT intercooler setup.

Kenodog · Joined: 25 Jun 2003 Posts: 2669 Location: Vancouver,B.C.

The intercooler itself is a Spearco B-252 core with a couple of cast end tanks welded on.You can see them on the Turbonetics website.It actually is very similar to the "cubic" shaped evaperator from a 931 A/C unit.All in all it takes up about half of the space in the battery compartment.
_________________
1979 Euro 931, Olive
1981 931, Sabine
1991 Ford Ranger XLT 4x4, Ricky
1996 Ford E-350 ex-FedEx Van
2014 Mazda CX-5 (Kinderwagon)
2019 KTM 790 Adventure
2024 KLX300
2024 KLX140

Petrovich · Joined: 27 Sep 2005 Posts: 235 Location: Rockville, MD

Yup, I was thinking of doing it the Lotus way - they just took an AC evaporator and cased it in such a way that air would pass through one half of it, turn around, and go through the other half. However, that requires the battarey to go away. On the other hand, using a heater core would allow you to go 3-pass, and still have a relatively flat unit that fits over the valve cover; however, I'm not sure of the transfer capacity of the heater core. I know it's more than enough to passively cool my computer (which is hot hot hot, overclocked to hell), but I'm not that sure about a car

How much air (in Lb or kg) does 931's 2-liter eat at full boost when making, say, 250hp?...