'86 944 Swap Underway

Hi all! A friend of mine who has a couple of 944's turned me on to the idea of doing an LSx swap a few months back. Having been a Chevy guy (still am?) in the past it seemed like a fun project.

I just picked up an '86 NA in fairly good condition with a blown head gasket and various other engine leaks. Excepting the dash, which has only a few tears, the interior is in remarkable condition. The sunroof was trashed (I'm 90% done replacing it and the open/close mechanism) and it needs some minor body work. It was a good find.

Anywho, I've started gathering parts. My plans are for a mostly stock parts build excepting what I need to make Chevy work with Porsche. I only want to worry about one thing at a time. Towards that end I've chosen:

• LS1, 2001+
  
• Full smog (AIR, evap, cats, secondary O2). I'm in California.
  
• Mustang hydroboost. Already ordered.
  
• Stock type clutch/flywheel/slave in a one piece C5 bellhousing (they seem to be easiest to find).
  
• AN fittings and hoses for power steering, clutch, fuel, and oil.
  
• A smattering of necessary TPC parts (mounts, adapters, oil pan, clutch disc).
  
• Custom or aftermarket radiator.
  

I have most everything in hand at the moment. My two outstanding concerns are:

• What radiator should I use? I'm keeping A/C and would like something that fits mostly stock (or close to it). The 951 unit is expensive enough to justify going aftermarket but fitment is an issue.
  
• How to mount the hydroboost. My current plan is to drill the necessary holes on the firewall or modify the bowl but I've heard of people using mounting plates. What's the best way of going about this? I only want to do it once.
  

And here's a pic of the 944:
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Glad to hear that you are about to get started and have started gathering your parts.
As far as the radiator, You can use a 951 , as long as it's in good shape.
Make sure your bell housing in for a standard transmission, the one piece automatics will not work!
You will need to make a plate for the hydro booster, you can't use the "bowl" . it will push the booster to far out and up in the way of everything.

Thanks for tips. Is there a one piece manual bellhousing? In my reading here on the forums I've seen where a one-piece as well as the adapter was modified to fit. Is that not the case? I ordered the bellhousing yesterday so I can probably cancel it.

This is the post I was referring to and the one piece bellhousing I bought: [You must be registered and logged in to see this link.]

TPC was working on a custom radiator with the correct inflow and outflow necks to make plumbing much more simple and direct

As long as it's a true Manual bell housing it will work fine.

Admin wrote:As long as it's a true Manual bell housing it will work fine.

It's not. I suppose I could notch the bell but that seems too hacky to me. I've dug deeper and may have a line on a two piece. If not GM Parts Direct has them for an ok price.

Looking for a 951 radiator that doesn't suck at the moment...

In other news, does anyone know the size of the steering shaft or the model number of the Borgeson u-joints that Xschop or anyone else is using? I'll be making a custom shaft with an extra joint to clear the stock Chevy manifolds.

EDIT: Nevermind, it's a Borgeson 014928.

You could get a new griffen or universal summit rad -------------> [You must be registered and logged in to see this link.]
Its on sale for 157$ right now too! It is a tight squeeze but it does fit.... [You must be registered and logged in to see this link.]

Or

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Will that Griffin even fit with the AC condenser in place? It's a lot thicker. Do either of those require cutting? And how much?

im running a custom griffin. its exact dimensions of the 951 radiator with chevrolet outlets.

You can hack all you want, but the auto bell housing will not clear the pressure plate.

BlueDragonX wrote:Will that Griffin even fit with the AC condenser in place? It's a lot thicker. Do either of those require cutting? And how much?

They both will require cutting / griding some of the old sheet metal brackets along the sides. I basically had to ground the bracket flush to slip the summit rad in. You'll have to make some custom mounting brackets too... Im not sure if the ac condenser will fit with either of those rads; I didnt hook my ac up and I removed the condenser. Your on your own there...

Hey there!

I'm BlueDragonX's friend that's crazy enough to have a pair of 944s, a 928 and also convinced him that doing the LS944 swap was a good idea (because clearly more Porsche projects were needed). Just popping in to say Hi -- I'll be helping BDX as much as I can (though hes really much more an expert mechanic, I'm just an amateur hack), and perhaps chiming in on the thread with photos / questions from time to time

Cheers, and Happy New Years!
Zach

good to meet you both here. welcome to the madness...lol.

We spent last Sunday pulling the engine and front suspension from our parts car. Trying to free up space by getting it out of the way. We also need the engine for another build we have in progress.

I also finished up the repairs to the sunroof. The PO destroyed it during a tow.

My clutch kit and hydroboost arrived. My parts list is otherwise nearly complete. I should start ordering the rest of the parts in the next week or two.Then on the hunt for an engine. I'm still on the fence with how much money I want to spend there so we'll see

Been a while since I posted. Been doing a lot more design work and building my parts list. This week I started ordering everything on that list.

Everything I need to assemble the drive train is on order. If only I had an engine to to go with all of that

I've got a handful of specialized fittings ordered for converting various plumbing to AN. Have what I need to get the heater all hooked up. I've got one major order to put through Summit once I consolidate the list to part numbers and quantities. Then I have to find a radiator.

We catalog everything we've pulled from our parts car tomorrow and hopefully send what remains to the crusher soon so we can free up some space in the garage. Various maintenance on the other 944's on the garage needs doing as well. Then I'll dive into the swap.

And unrelated but because I can, here's me with a sawzall and a 944:
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Ok, I'm trying to finalize what I need to get the cooling and braking systems plumbed.

For cooling I'm using a brand new stock 951 radiator. My questions are:

• What size splice do I need for the upper radiator hose - I'm going with the Dayco E71751
  
• I'm T'ing the LS1 steam line into the reservoir line. What size are those lines or is there a part number for the T that I should be looking for?
  

As to brakes I'm using a later Mustang hydroboost (I believe it's out of a 2001) with metric threads. For that I haven't been able to figure out:

• What thread size and flare type are the Mustang brake lines
  
• What thread size are the 944 brake lines
  
• Is there an adapter someplace, and if not, nevermind :p
  
• I've got an email in to Xschop to see if he has a hydroboost mounting kit available, but barring that what's the best way to mount the thing? I'm looking into having a custom plate fabricated similar to what's in the manual but I'm concerned that this may not be the best approach for fitment.
  

Any help is much appreciated. Thanks guys!

We've been getting settled into a new garage the past two weeks so no work has been done. Also still waiting on a few new parts. Hope to do some actual work tomorrow and go engine shopping in the next few weeks, but we'll see!

I do not plan on making any more hydroboost plates for the 944.

xschop wrote:I do not plan on making any more hydroboost plates for the 944.

OK, thanks. I'm working on designing something myself at the moment.

Do not "T" the steam line into the reservoir, Hook the steam line from the engine to the top of the radiator. Just plug the line from the reservoir. This will keep the engine from sucking air into it as it cools down. "T"ing it makes it really hard to get and keep all the air out of the system.

The fitting sizes for the Mustang master cylinder are 12mm x ? (not sure of the thread) with a 4.5mm line, the other is a 10mm x ? with a 4.5mm line (it is the same as the Porsche)
Both are bubble flare type lines.
You should be able to buy a short pre made line from your local parts store that has the 10mm bubble end , on both ends and then one with the 12mm on one end and a 10mm on the other, then just use bubble flare splice connectors to join them to the Porsche lines.
If you still have your parts car, you can get two straight splices from the passenger side battery area , where the brake lines go through the fire wall . You can also get a bubble flare three way connector from under the passenger side rear area where the rear hard lines are mated together.

Thanks for the info! That's some good stuff. I was looking at how PorscheDoc did his brake lines as well. That all helps a lot.

I just barely started pulling parts off my car this morning. We're rebuilding a stock 85.5 engine at the same time that I'm also involved in. Too much stuff going on.

More progress made! The engine is completely removed and most of the engine bay has been stripped. I've decided I'm going to do the body work and paint before I put the LS1 in so that ordeal begins now. I've got more parts to take off, of course, and body panels to order, but the progress is good!

Swordfish (the 944) and myself.
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The engine next to the remains of one of our other cars' engines.
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