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[Rich H]

Been searching - drew a blank.

The plan:
The space over the cam cover is a wedge shape, 12"x7"x3.5" at it's deepest (Outer) edge, 2.5" at the shallow end.

In this space create an airbox containing a radiator core of soem descriptiion

Use m6 standoffs and rubber mounts to pick up the cam cover bolts.

The current plan is a MGB heater core as it's copper and then case it in 1mm brass as it's easier to form and solder. (The main reason for using this core is that it was 99p... )

Then fit another oil cooler core under the LHS wing (By the horns) and a pump in there somewhere. It could probably do with an expansion tank + rad cap if it gets too hot and soem sort of bleed valve right at the top as the chargecooler will be at the highest point.

What do you all think?
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1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

[pocketscience]

Sounds interesting. I think I can picture it. Will the heat from the exhaust manifold be an issue with the performance of the IC? Will the IC be large enough to produce significant results?


G.
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Whoever said you can't buy happiness forgot about Porsche!
81 924 N/A, GTS lights, Saratoga, interior, headers, Integral cam, EFI (sold)
95 993
69 911

[morghen]

undess you are dragracing it i think youre always better with a air to air intercooler.

i have a friend with a supercharged VW corrado, absolutely blows my doors on the first 400 meters but then the water heats up and i pass him.
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[Rich H]

That remains to be seen, I was thinking an ali plate heat shield would be a good idea and the heater matrix efficiency is obviously unknown, it's an old design but I wanted a copper one so I could incorperate it (And modify it) more easily than an ali one. If it works then maybe a proper ali unit could be commissionned.

It will be compromised by heat soak to some extent, however I was thinking that the return pipe from the matrix soldered to the lower edge of the IC nearest the exhaust will assit in cooling the whole affair. A nice big modern oil cooler will provide more than adequate cooling capacity, couple that to a tank with a BOV should it get too hot (Like the normal radiator) it should provide sufficient capacity to sink a fair amount of heat.

I did even consider using fuel cooling (So the circuit would be air-water-fuel or Air-fuel rather than air-water-air or air-air) but decided against it... Yes it sounds daft but think about it.

The CIS returns most of the fuel provided by the pump to the tank all the time, that fuel then goes all the way down the car in a steel pipe in the airflow to a huge tank of cold fuel. Heating it up a bit won't matter much and the hot volume is small enough to be dissapated in the main tank. It is used on aircraft all the time. Trouble is the fuel volume is probably not enough to remove a significant amount of heat. Could run another set of lines back there and have a fuel cooling circuit seperately, HVLP, but it's lot of work - just a thought.

(I know it's unconventional and I don't really care that someone will get in a flap and say heating fuel up a bit is 100% lethal and you will obviously die instantly - because it's not true! )
_________________
1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

[gegge]

The MGB heater core inside an airbox, that is brilliant! The normal configuration is usually the opposite, an intercooler with welded endtanks on the sides and fill it with water. Used as a "heavy" heat sink it does the job, in traffic and for short bursts - even better than an intercooler.

I was going in that direction too and tried the Toyota ST165, Lotus Esprit and a Garrett core. Did end up with a GT intercooler...
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Carl Fredrik Torkildsen

924 turbo -81 Carrera GT RESTOMOD
924 turbo -80 Dolomite De Luxe
924 -85 DP kit, BBS RS, M030 and tuned engine
924s -86 Black on black turbo with Fuchs

[Rich H]

I'm still planning on having waterflow to an oil cooler radiator

A heavy heatsink will not last long seeing as the charge tube gets so damn hot!

How about an AC compressor and AC cooling unit...
_________________
1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

[ideola]

You will probably still need to make clearance accommodations on the hood. I've looked at this over and over. Even the Mazda RX7 TMIC requires massaging the hood, and it is one of the thinnest I've seen.

By the time you get the heater core into a plenum, you'll quickly run out of room over the cam cover, and you still have to deal with flattening the charge tube to get it over the cam cover and into the TB. I do like the general concept, however.

There will be two factors you'll need to figure out: 1) getting enough of a differential between the charge air and the coolant. Read Corky Bell's chapter on calculations for how much fluid you'll want to plan to run in order to determine the size of your circuit & reservoir; and 2) more importantly, is the design of the heater core sufficient for high volume / high pressure air flow? This is the much bigger question in my mind, since heater cores by definition are designed for high volume / low pressure scenarios. I'm not sure that the fins in the heater core are designed to induce sufficient heat exchanged with high pressure charge air.

I'd love to see you execute this, however, and get some documented results...if the heater core approach works in a chargecooler setup, then my plans for a refrigerant-based aftercooler should work too!
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erstwhile owner of just about every 924 variant ever made

[morghen]

you could always modify the cam cover for some extra mm/cm but then again from this to straping on some wings, a flux capacitor and flying to the moon with it...it'll be a small step.
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[Rich H]

Efficiency is always going to be compromised in this situation.

Heater cores are quite compact generally, and I believe I have enough room. Hell a 924 core would fit! Ali would be best, as whoud a proper radiator core, but I can't handle ali as easily as brass. The heater core appears to be long and thin in this case, until it turns up I have no real idea TBH though.

They are not the most efficient, however they should also not present much of an obstruction. Essentially this one is straight copper pipes with lots and lots of copper fins.

The plan is to have the heater core over the outboard edge and then the rest used for the taper. I figured that if I could get it down to the same size (Posdsibly wider) as the boost tube size it will be fine.

The charge cooler is the key to it all, so I'll have a crack at that first, will only be a few ££ if it all goes wrong.

I'll draw something...
_________________
1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

[Rich H]

Black dots are water in/out.

Water connections will probably come forward, the return running under the outer edge, the feed running straight to the front tank.

Infact thinking about it how about making the whole lower section the return pipe, will slow the flow down in that section and soak up the exhaust heat in a larger volume of water, topsuide will be incontact with the lower sid eof the matrix and the outside will be in the hot air form the engine. Will slow heat transfer to the lower edge.
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1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

[Shurick]

What about this thing?

http://www.hi-flow.com/HPIC1.HTM
You can obtain those "laminova" cores and build your own IC. By the way, why not to install them into receiver?
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WBR, Shurick
'79 931 -- intercooled K26-3060-6.10 turbo @ 1.2 bar, EFI+EDIS, 951S brakes, stripped interior, 951 look.
'86 924S -- R.I.P.
https://www.instagram.com/ru_pacecar/

[morghen]

copper...hmm..be very carefull not to get water into they cyls...you will bend the internals and can even damage the block.
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Supercharger and EFI kits
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[ideola]

There are two ebay sellers right now that have the laminova cores available for $50 each or less...

...would require some significant plenum fabrication, but Rich's arrangement might be ideal for the laminova cores...
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erstwhile owner of just about every 924 variant ever made

[Rich H]

Good spot Dan! Have mailed him for a price on shipping. I can fit them with O ring seals - no need for welding.

Morgen: agreed I need to be careful but I figured it's more likely to either spray water through a crack (While it's running it will inject very little per cylinder - think water injection)

If it lets go altogether then it'll run down towards the turbo instead...!

I'll pressure test it all first though, needs to be water and air tight.
_________________
1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

[morghen]

i dont want to be negativistic here but i think what you've drawn there is too small and it wont be effective.
You need an intercooler for more than 200HP...for that you need to calculate the core size, amount of fluid depending on where you want to mount this thing. have you read corky bell's book?
if you want..i have my chart of calculations and aproximations wich lead me to a very effective intercooler...the charge tube right before the TB is ICE cold even at WOT.
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Supercharger and EFI kits
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