924 Garage " ... the best handling Porsche in stock form.", J Pasha, Excellence

LJ's 931 Project

Up Ewing's 931 Frank's Carrera Convertible 924 LJ's 931

Coming Home: January 98

Pushed the Burb all the way home from Delaware so the 931 must be in great condition, Hey! If not that's OK. If it only is useful for parts, then fine. And if it runs? Gravy. Paid $600 for the parts to convert my 924 to M471 suspension and brakes, rear hatch with spoiler, 16" forged wheels. So ending up with a running turbo is an extra we don't count on. 

Those '928' wheels are sure gonna look good on the 924. (They arent' really: different width)
Let's just get it parked and get to work!
Too bad someone dropped the hood on the lift support and bent it:

Lets See What We Got
or
Will This Sucker Run?

It cranked so now we gotta get the fuel pump running. Clearly the biggest thing wrong is FPR (Faulty Previous Repair). The wiring was mangled and suffered from corrosion in the box and various connectors. Someone had previously been into the fuel pump relay section and they did not display much finesse! For now we will just jumper the fuel pump with a toggle switch. We need to be able to keep the pump running for diagnostics on the system anyway.
I promised his mom it would take a long while to make it run. But then Uncle Ken came to visit. Sorry Mom. Left em alone half a morning and they managed to assemble the fuel distributor and injection system from the pile of parts (literally) we found on the front seat. A little rough. OK, a lot rough. But it runs so we got us a rebuild project. There went my 924 parts. Do you think LJ wanted to get this done? Can't tell from the picture; but it was raining.

Pull the Mechanicals


Bought a case of penetrating oil.

 

One happy 931 restorer! You can,t imagine the endless hours working with corroded fasteners on the worlds most cramped engine compartment.

Summer is passing us by. Need to get the engine bay stripped before winter.


With the engine gone it just almost will not stay down. So the wooden support.

Learning by Doing
or
How Bout a Subdued YELLOW

 

Typical battery shelf corrosion. Pretty bad. I recommend the Sears MIG welder. It has the major advantage of coming with a Sears charge account. To really repair this the air conditioner unit must be removed from the passenger footwell. 
 
Not sure if Uncle Ken just likes working on cars or could it be his sister-in-laws cooking? Both I bet. In any case; he returned to give LJ spray lessons.
Not great. But not bad for our first.
This is the battery are after repair. Not pretty but functional.

There is a reward to the first person who can tell me why this brace/piece/tube is on the 931's frame.

Michael J Brown has a theory; "Looks like a tube that creates a low
pressure in the frame to draw the air from the back hatch thru the doors." Huumm. Does he get a reward or not?

The Power Section
March 99

enginwoilpump.jpg (12249 bytes)The bolt holding the timing belt pulley defied heat, levers, electric impact wrenchs, (rented) air impacts, foul language and all combinations of the above. That's why the oil pump is still on. Finally got it off with an 'industrial' quality air impact. And it was reluctant then too! It is a 34mm but we find a 15/16 is a much better fit. Thanks to Ray at ASG in Fairfax, VA for getting this sucker off.

badpiston.jpg (12835 bytes)This is what we found. Sumtin was in #1sometime when the engine was run. Well, LJ been wanting to get some of them high compression pistons. Maybe he'll get his chance, or excuse! Anybody got a piston or a piston set collecting dust?

LJnCharlie.jpg (41371 bytes)

Charlie Murphy at Intersport shows LJ how to inspect the block and related parts. If you are in the DC area with a 931 Charlie at Intersport is a hard combination to beat. 

Well, the bad news is LJ needs a bunch of parts. The good news is he'll have a dynamite engine when finished.

The plan: Line bore the bearing caps then Bore it out ALL the WAY. Why not. New JE pistons going to 8.5/1cr. US made gapless rings and stainless valves. The head needs to be surfaced. Since we need a new cam maybe a little more than stock on the grind?

We have it on good authority that these improvements will bring an 80 from 143 NET hp to 174 HP. The cam is good for 10HP. There will be much more torque than before as well and the powerr curve will build from about 1800RPM. The low-end flat spot should vanish.

Our goal is 200 HP. It should be easily gotten. An1981-82 DTC ignition would be good for 12 HP on the
original over the 1980 cars. Boost up to 12 pounds (.81 bar). A Corvette eater at the autocrosses. And very reliable. The best method on the boost is to shim the wastegate spring or run a balance knob that slightly pressurizes the vent side of the diaphram to raise the total boost  in the system. The DTC will compensate the timing much better than the 1980 system.

An 1981-81 intake runner, manifold, throttle plate and intake manifold as they are improved and flow much better than the 1980 as well. This will make the engine pull from about 1500 rpm and then peak at
about 5900 rpm on the horsepower curve.

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