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 3.6Click to view attachment

Awesome that you are doing this, but is it less work than your previous heat exchangers? Seems to be a lot of used ones on Ebay for around $600.00 or best offer. I still have a set left over from my 3.6 project.
@mb911 would you trade my 993 heat exchangers to modify my front bumper for a GT?

Yeah would do the trade that’s reasonable. These are less work and I am in complete control of the product as I them entirely myself so no BS.

I'll be helping @napasteve Steve with his 3.6 swap. He has the '95 engine from @mepstein Mark and it has stock heat exchangers on it.
You all know I'm completely ignorant about "regular" engine swaps so help a brother out:

Does Steve need a set of these?

Thanks in advance.
Chris

Yes it he wants heat or go with the junky b&b or find an old set of what I made years ago. The 993 heat exchanger is really a nice heat exchanger in general

“This is a hard process to quote that’s for sure as it is straight up custom.“

At our shop, the translation is: if we charge you time and materials, the price will sound obscene so we’ll just settle on a price that we can both live with.

I appreciate you doing the set for me. I actually have another set that’s already been modified for my 67, 912/6 build but I guess that’s a lot easier than turning them around for a 914.

@MB911 - Ben, can you post an installed picture with them hooked up? Do these flow better than your original, large-tube SS heat exchangers? Will they bolt up to a stock banana muffler? Thanks and Happy Thanksgiving, Michael

Here is the prototypes on my car. Do they glow more I would no probably not. They are unequal length but 1.625 OD just like my old sets. They connect to a stock muffler that’s the idea. Click to view attachment

I will probably do a second set like you and I discussed. As soon as I find my groove on these the build time will get faster and pay off.

Is there any possibility that you could sell me the unassembled parts and let me try my hand at welding them up? Never mind if that is PITA question.
Warren

I'm in for a set as soon as I get the donors to send you.

My six conversion originally came with 993 HE's. Nothing as polished as what Ben's done, but do remember they worked well.

These look really clean.

Once I get the details hammered out for more of a production setup sure

@MB911 do the open ports in your pic get a hose from the engine blower fan? Left open? How is the power and heat? Some people live in cold climates...

lol I live in Wisconsin you don’t think it gets cold here? Basically the factory ports are shrunk so a standard hose will fit . I then cut a new opening for the heat valves and it works perfectly. It was 40 degrees the last time I was out driving and toasty in the car no problem

Starting the adapters. Click to view attachment

The cold remark was for the CA folks that chime in and say they don't need heat, grrrr.

Gotcha. Will be adding those ports next.

BRRRRRR!!! - It is 43 degrees outside right now; I am at the foothills of the Sierra, in Auburn, CA.

30 here

You have to figure if they are going to work in a factory 993, they will easily heat up a 914 cabin.

20 and snow this AM

We are getting there this weekend

Headed your way!

Ben,
How do you deal with having to flip the flanges on the left head exchanger for the 964 engine? Do you move the access tubes for the bolts??

Also, I have a set of these heat exchangers. How much to get them converted???

Clay you have to be very patient and do them with out access tubes. I have been flipping the flanges on these for 25 years now it works but it’s a fresh day kind of thing not after work.

These sets I quoted 1500 to do the conversion on. May go up a little but that’s what I would do them for you for as well. You helped me a ton. Moving forward 2k . It’s a lot of work.

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. 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.

Very nice looking heat exchangers conversion!

Is there any advantage on these vs. the headers/heat exchangers you used to build?

I think the ones I use to build and then contract were probably better but these are a great option. After the exhaust business went sideways I got rid of anything that resembled it and having these on a short stroke turbo years ago made this natural

@ClayPerrine

Is the 964 head drilled and tapped for either direction flange? I thought they were so you could use any flange rotation. Rotating the flanges is the biggest PIA if not necessary that saves a bunch of time and money.

I'm the customer that Ben is making these for. I'm sure it will be another masterpiece. It's for my 993 powered GT Tribute that currently has regular headers on them. I'm looking forward to having some heat in the cabin for those chilly days.

1 of the 3 currently. And I am excited to be getting them done. Ordered more parts today for them. Will have them Sunday and will spend some more time this week on them

Mine is not setup for 4 stud pads on the heads. So I am stuck with the rotated flanges.

I have a set of 993 heat exchangers that have the flanges already rotated. But I want to redo the way the heater boxes attach and the output flanges.

Clay

^ 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.



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)

Well let me know I might be able to help you with the flanges already rotated that saves a bunch of time and money

Hi Ben, did you use the OEM type head to HE gasket on your 2.4 set up?

John

Yes

Great, thx…looking forward to more stories on this set up.

J.

Click to view attachment Click to view attachment

Click to view attachment

Ben @mb911 These are a thing of beauty. Maybe this is a good model for you to make some money for a great product for the guys that are in need of Heat Exchangers in there big 6’s

Your work is really impressive!

Best Bob B

I hope so. They are a pretty good value

Purdy!

Any time Ben has mentioned something he wants or is willing to make, I’ve always said I’ll take one. This is no different. Even though his product line is getting cut way back, the 914 community has really benefited over the past ten years and I’m really grateful for what he’s contributed.

Agreed^ These might be a good value as I think I have a set of these a friend was going to give me. There seems to be a fair amount of take offs so the cores might be easily available for low cost.

The biggest issue so far is finding reasonable cores. The ones sent to me by clients so far have cost them about $500 and then they are into me for about $1500 (supply chain issues changing pricing which equals more time on the next sets I do) your in $2000 pretty easily

Click to view attachment

An excellent option as Ben's original heat exchangers are no longer available.

Where is the other heat port after you are done? Did you show it in the older pics?