993-914-6 heat exchangers Options

[mb911]

I have been dragging my feet doing these but got a good start this morning. This is a hard process to quote that’s for sure as it is straight up custom. I run this set up on my hot 2.4 with 1.5” sleeves and they work really well. A good solution all the way up to 3.6

[horizontally-opposed]

Very interesting project for those of us with six conversions who haven't found existing paths compelling.

Porsche learned a lot about heat exchangers from 2.0 > 3.2 liters, and again in the 964/993 era. Bruce Anderson told me they inspected SSI HEs and tossed those on the pile marked "not invented here," but the later factory HEs learned from the same rust-driven inputs SSI did.

I'm curious about whether these improve or decrease access for valve adjustments vs headers and Dansk's mild steel HEs, also curious about thoughts on flow for engines smaller than 3.6 liters. Asking for a friend with a warm 2.2 making ~200 hp at the flywheel with an SC-ish torque curve courtesy of a little head work and Solex cams. (IMG:style_emoticons/default/smile.gif) There's probably a bigger market for 3.2-3.8, engines that aren't well served by Dansk's offerings so far as I know?

Also curious about impacts, if any, or deleting one side's HE as I don't need a lot of heat—just enough to keep toes warm on yesterday's top-off fun run through crisp cold, and perhaps a windshield clear on longer journeys with the roof on. In example, would deleting the driver's side "box" (to offset the weight of the oil tank and driver, albeit minorly) create unbalanced engine cooling?

It's a given that the carbs will have to be retuned to account for different headers, but the prospect of heat and high quality—not to mention a chance to support one of our own vendors—could end up being very compelling indeed...

[mb911]

Very interesting project for those of us with six conversions who haven't found existing paths compelling.

Porsche learned a lot about heat exchangers from 2.0 > 3.2 liters, and again in the 964/993 era. Bruce Anderson told me they inspected SSI HEs and tossed those on the pile marked "not invented here," but the later factory HEs learned from the same rust-driven inputs SSI did.

I'm curious about whether these improve or decrease access for valve adjustments vs headers and Dansk's mild steel HEs, also curious about thoughts on flow for engines smaller than 3.6 liters. Asking for a friend with a warm 2.2 making ~200 hp at the flywheel with an SC-ish torque curve courtesy of a little head work and Solex cams. (IMG:style_emoticons/default/smile.gif) There's probably a bigger market for 3.2-3.8, engines that aren't well served by Dansk's offerings so far as I know?

Also curious about impacts, if any, or deleting one side's HE as I don't need a lot of heat—just enough to keep toes warm on yesterday's top-off fun run through crisp cold, and perhaps a windshield clear on longer journeys with the roof on. In example, would deleting the driver's side "box" (to offset the weight of the oil tank and driver, albeit minorly) create unbalanced engine cooling?

It's a given that the carbs will have to be retuned to account for different headers, but the prospect of heat and high quality—not to mention a chance to support one of our own vendors—could end up being very compelling indeed...

I run these on my 2.4 with 1.5 inch sleeves in them and they work really well for me. I know you have talked many times about one heat exchanger but why ? If you have 2 of the cores make them both functional and if you don’t hook up the other side so be it. From a valve adjustment standpoint point they are about the same as any other heat exchanger. Nothing is easy while the engine is in the car.

[horizontally-opposed]

I run these on my 2.4 with 1.5 inch sleeves in them and they work really well for me.

^ Cool, and good data point.

I'd imagine they're good for a warm 2.2 then as well, perhaps sacrificing a little torque down low while gaining a little top end power. I'm sure a bit of dyno time would be required to readjust the carbs, but that would be well worth it to regain substantive cabin heat.

Have long been weighing $3k for non-factory HEs vs other paths such as heated seats, gas heater, electric heat, etc. Most solutions have been tough to justify for an occasional use car, and one mainly used on warm days. I doubt I'm alone in that, so I'd guess there is a reasonably sized addressable market for a solution that presents real quality and real value. This seems promising.

I know you have talked many times about one heat exchanger but why ? If you have 2 of the cores make them both functional and if you don’t hook up the other side so be it. From a valve adjustment standpoint point they are about the same as any other heat exchanger. Nothing is easy while the engine is in the car.

Reasons would include:

Weight & complexity (HE shell + flapper valve + hoses + linkage)

Need for my use case vs 914 as a daily car in period (I found SSIs oversupplied my cabin with heat with a four; I was often turning the heat down on cold days with the roof off, and I also remember heat bleed from the longitudinals on very hot days even after buying new flapper valves, to the point of turning on the heat at the windshield in the hope if would bleed off—so cutting off 50% of the source is interesting to me)

Access (agree few things are easy with the six in the car)