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Rich H · Posted: Fri Oct 16, 2009 1:41 am Post subject:

No calculations - all lashed up

It's all constrained by the space available so it's never going to be ideal.

The idea is to improve the inlet temps to reduce the chance of detonation. Not planning on upping the power yet, if I do it'll be a 1 bar WG spring.

Just something to keep me busy

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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

flosho · Posted: Fri Oct 16, 2009 2:53 am Post subject:

This is jmho, but if at all possible I would go front mount intercooler, end of story.

It may take additional planning, and some more cutting or modifying of the chassis, but it will be highly worth it.

I've had an air/water intercooler, it worked nicely, but it was overly complicated for what it was. A front mount would be much nicer.

Also I agree with morghen in that, the core you'd be using would probably produce a pressure loss and not be all that efficient. It may drop your temps 20-40 degrees but that's still over 100 degrees F on a hard sprint.
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[This Space For Rent]

Rich H · Posted: Fri Oct 16, 2009 3:05 am Post subject:

Not cutting the bodywork at all - This is to be strictly bolt in.

Agreed if all out performance is wanted a FMIC is the way forward but I'm not after ultimate performance just lower inlet temps.

Also agreed the core is highly dubious and may end up being worse than nothing.

That said 20-40 degrees drop is still 20-40 degrees drop.. Coupled with a bigger wastegate spring (WG is being overhauled anyway) means more power while maintaining a balance of inlet temps.

If it comes to nought then it won't cost me much, the plan is to buy a new oil cooler for the external rad so if that doesn't work it can go on the Elise. The pipework and sheet metal will cost a bit, but I'm willing to spend a bit to explore the possibilities

Much like the old EFi setup on my N/A- not worth it for power but a technical challenge.

Keep the ideas coming though!

Rich
_________________
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 · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

it all depends on personal taste and intuition...I am always going for the overkill...i've calculated my IC to be good for 300HP even if this engine will probably never produce that power.
The ideea was exactly the same as yours...i was not planning to upp the boost but just to prevent detonation. However that didnt last long....i mean keeping the boost stock

it's addictive..you'll see !

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Supercharger and EFI kits
https://www.the924.com

Rich H · Posted: Fri Oct 16, 2009 3:28 am Post subject:

Your probably right... Where is that CGT bodykit...

_________________
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 · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

For temp reduction, the most critical factor is temp differential between the hot charge air and the cooling medium. I don't see this as a concern with your heater core.

The secondary factor is heat transfer. The fins on the heat exchanger have to slow the air down enough to exchange heat, and this is where I think the heater core is going to be deficient...how much so remains to be seen.

Given that heater cores are designed for high volumes of air, I don't think the core itself is going to introduce significant pressure loss, nor do I think the plenum design will...it's certainly the most direct path from the turbo outlet. So I don't see pressure loss as being an overriding concern.

I think the biggest challenge will be getting the heater core to exchange enough heat while the air is passing thru it. Those fins are designed quite differently than the conventional intercooler fins. This is where I think the Laminova design would be far superior. If you could pick up a couple of those cores for $25 each, it might be a good back up plan. If you design your plenum carefully from the outset, you might be able to keep the plenum and simply swap out the cores if you find the heater core to be deficient.
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erstwhile owner of just about every 924 variant ever made

Rich H · Posted: Fri Oct 16, 2009 4:22 am Post subject:

That was my plan. Have asked about 3 cores and shipping to the UK.

Hopefully won't be needed and my design will be awesome... Might have to rename the thread the Ultimate Chargecooler....

_________________
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 · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

flosho · Posted: Fri Oct 16, 2009 7:10 am Post subject:

Rich H · Posted: Fri Oct 16, 2009 7:39 am Post subject:

OK thanks, duly noted. I'll investigate.

I don't really see how to get air from the turbo out the front of the car and back again easily.
If it's possible to do without cutting and without miles of pipe I'm listening! A double pass IC would be best I think so all the pipes come out RHS but pipes are tricky...

I'm still not sold on upping the boost much, but seeing as the WG will be out it'd be rude not to change the spring...

Keep the ideas coming!

TBH I want to try my hand at fabbing in brass

Rich
_________________
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 · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

miles of piping is not a problem if you use propper diameter pipes.
_________________
Supercharger and EFI kits
https://www.the924.com

Rich H · Posted: Fri Oct 16, 2009 4:56 pm Post subject:

How about routing then? Seems very alkward, but not looked that close... Still want to try a chargecooler though.
_________________
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 · Posted: Fri Oct 16, 2009 5:00 pm Post subject:

andial want $183 for a wg diaphragm and 1 bar spring shipped to the UK!

_________________
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 · Posted: Sun Oct 18, 2009 4:27 am Post subject:

Core has turned up and it's not far off the perfect size! Good condition too. Water fittings will need to be moved most likely, but that's not going to be too much trouble.

70x80mm which fits over the cam cover almost perfectly.
There are 30 tubes are 3x10mm and there are hundreds of thin copper fins.

Very happy!

Need to find some brass plate, solder and flux now...
_________________
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 · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

Hey Rich, how about a photo?
_________________
erstwhile owner of just about every 924 variant ever made