So, in the process of building my GT style 914/6 I'm working on the oil system. I'm not too fussy and if a part is not apparent, event with the hoods open, I don't care too much if it looks original or not.

The original 914/6 GT cars used a front oil cooler that was a very close relative to the 906 oil cooler. If a 906 cooler is rare and expensive, an actual 914/6 GT cooler must be in the "mortgage your house and promise your next born" category. And I don't mind saving a fe bucks if I can.

So I've come across this idea for the front cooler. I bought a 928 automatic transmission oil cooler. The cooling portion (between the end tanks) is 23 inches wide, by 2.75 inches high. The cooler is 1.25 inches thick.

Here are a few pictures.

The part number:

Looks okay, and it is a Porsche part.

And the end tank where the ol lines connect. The inlets are small, 5/8 inch outside diameter. And I know all the dimensions are really metric, and I'm Canadian, so I should be using those. But the stupid tape that's handy is imperial only.

what are the inlet sizes? 3/8?

a six needs minimum 3/4 lines.... (-12)

Here's a bunch of pictures of the real part. I don't know how Armando finds all of these

http://www.pbase.com/9146gt/9146gt_front_m..._oil_cooler_no1

Dimensions of the original appear to be something like 23.5 X 4 X 4.

So I'm thinking that I may buy another one of the 928 oil coolers (they're cheap, I paid $40 for the one I have, used) and organize it in series with the first. They would sit one behind the other in the car, oil would come in at the end of the rear cooler, flow across, through a new fitting to the front cooler and then back through the front cooler.

It would mean substantially modifying the coolers, to change the fittings, which should normally be 30 mm thread, and making a connection between the two coolers at the other end.

The advantages are: Behr parts, kinda funky, dimension close enough that it would fit; cheap in parts, probably semi-cheap in aluminum welding time at the machinist's shop, (I'm not equiped to weld aluminum).
Disadvantages: uses old coolers of unknown origin, requires a lot of fiddling.

Does anybody know how to estimate the cooling capacity of an oil cooler ? How do I estimate the cooling capacity of my possible solution to the cooling capacity of the original ?

Thank you all for your input.

Michel Richard

Bad idea, you need to get at least -12 or equal inlets and outlets to the cooler..

Im sure the cooler you have can be made to work, but...

It might be cheaper in the end to just buy a nice sturdy Fluidyne cooler

I think that it depends on the size of the engine and what knid of driving you will be doing with your 914.

If you run a 6cyl engine ( and not to hard)with the engine oil cooler still conected then I guess you can get away with this small 928 trans cooler for a little extra cooling, possibly put on on top of the other.

I ran a Troutman oil cooler at first and I think that the angle was all wrong, it was very tall and had a steep angle. I would see 275 degrees at the track on the back strights of Sebring. I said to my self it's time to do something before my engine expires from heat.
I run 6cyl 3.5Li twin plug engine, After that I had Jarvis build me a front oil cooler from a 944 Intercooler, it works great ( a little big for the size) but it still fits in the original GT front cut out.
I also do not have the engine mounted oil cooler,
Thats was my solution.

I wish you luck with yours.

Quilmes

Quilmes,

Do you have more info on how the 944 intercooler was modified ? Pictures, perhaps ?

Michel

I'll spare you the pics.

My solution has resulted in no temps above 210°
This is after 30 minutes of track duty.

Search cooler and trekkor if interested


KT

You could also use a RX-7 Cooler as we have done on a 2.2 race car. It fits in the front cutout great. They are not too hard to modify. And the best part they are cheap.
Van914

Hi Michel


I would go with a Fluidyne cooler , I have a 2 pass cooler its very nice and Sturdy.

In your engine post you mentioned u would do some track time, that will drive the temps up quickly,
and on a High rev motor u will generate a lot of heat. Go with a minimium 12an fluidyne cooler.

Be safe......

It's a tough call on the price... say $40 for the part...$100 for welding and machining...you start to get near the cost of a new one.

This is an early RX-7 cooler...you need to cut the end off and weld on a new end. There's a T-stat to get rid of and I'd flange it, so you could clean it right out when all the work is done.

QUOTE (joea9146 @ Dec 24 2005, 04:09 AM)

Hi Michel I would go with a Fluidyne cooler , I have a 2 pass cooler its very nice and Sturdy. In your engine post you mentioned u would do some track time, that will drive the temps up quickly, and on a High rev motor u will generate a lot of heat. Go with a minimium 12an fluidyne cooler. Be safe......

Joe,

Can you say which Fluidyne cooler you have ?

Thanks

check out some of the race part houses, in general for what ever reason the 2.5 generally was pretty easy to cool. I had a rx7 cooler and never had an issue.

For this project I'd find a new one cooler, its easy for me to spend your money!!!.....

I think about it a little more, and my original idea may not work. I now remember that several people use the modified Rx7 cooler. The other option would the Fluidyne that Joe has, but I would prefer metric fittings.

There's an Rx7 cooler on ebay right nos

http://cgi.ebay.com/ebaymotors/RX7-2nd-Gen...bayphotohosting

Mark, is that what I would need ?

Michel

Don't get the early RX7 cooler as its steel, the 2nd Gen ones are aluminum and work alot better.

I was "told" mine is an early one...but it's aluminum so I'd guess not too early.

Was there a 3rd Gen?

Michel...the RX-7 cooler is an OK fit...not perfect but pretty good.

I don't know if I'd grab one without first checking it out in person. It sat real low in the RX-7. It was prone to corrosion and rocks.
That's why mine looks a little beat up.

Michel, I would go with the Fluidyne. You don't know what your getting with some of the used stuff. I lucked out and have a 944GTR cooler -16. I knew the car it was coming off (ex-LeMans car, going to a bigger cooler for vintage racing), so I knew I could trust the part and the person I was getting it from. On the track, the temp will not go above 205.

T.C.