Porsche 944+Chevy V8

Very cool project Don!! Been following along. I didn't comment at the time but I really liked the hi tech gas tank a few posts back, complete with bungee cord!

titleist1 wrote: ↑

Wed. Nov. 13, 2019 1:06 pm

Been following along. I didn't comment at the time but I really liked the hi tech gas tank a few posts back, complete with bungee cord!

Hay, whatever works for a temporary set up!

This evening I got the left side of the rear suspension back together. It's about ready to go back in. I think I will change the rubber brake lines before it goes back in.

-Don

A bit of a frustrating weekend car wise. Before we put the rebuilt torque tube in the car we need to make sure the nose of the driveshaft will seat far enough into the new, adapter pilot bearing. This requires mocking up the engine, bellhousing, adapter and torque tube. And making some careful measurements in places that are a bit difficult to get to. The adapter kit manufacturer says there should be about 1/2" from the bellhousing mounting face to the nose of the driveshaft. At first we had 7/8". The pilot bearing adapter sticks out about 1/2" from the back of the crankshaft. About 1" from the block to bellhousing mounting face. I moved the whole driveshaft forward about 1/2" by whacking the back of the driveshaft with a BIG hammer and a block of wood. It really didn't want to move, we destroyed a few wood blocks getting it to move that far. Currently at 3/8". We will have to mock it up again to double check that everything is right. If the driveshaft nose is not seated properly in the pilot bearing it will destroy the driveshaft.

-Don

OK, it's been a month and a half but I finally got back to working on this project!

When we left off last, we had banged the driveshaft forward in the torque tube to get it to push further into the pilot bearing. Unfortunately, When we mocked up the transaxle we couldn't get the coupler to couple. The coupler has two through bolts that clamp it to the splines on the driveshaft and the input shaft of the trans. There is a space where the splines are missing to accommodate these bolts. One on the driveshaft and one on the input shaft. The space between them was to great so both bolts could not fit through. The solution was to bang the driveshaft back toward the transaxle about an 1/8". Now we have the nose of the driveshaft into the pilot bearing about 3/8" instead of 1/2". I hope that's enough!

-Don

Today marks a milestone in this project. We've gone over the Hump! We actually put something back together!

Yesterday we finished with the engine/torque tube/transaxle mock up. That means we are almost ready to put the new torque tube in. First, out with the old torque tube. The 924/944 cars use this foam to insulate the shifter area so heat and road noise can't enter the passenger compartment from the hole in the tunnel. This foam is under the car and subject to the elements. After 30 years, they can be pretty Nasty! I'm not a big fan of Nasty so we will install a nice new piece of foam. There ya go, all ready to go back in with the shifter rod and the new foam. Slid it under, jacked it up, installed the little cross members and made sure the foam ended up in the shifter hole. FINALLY! We are starting to put this car together rather than taking it apart!

-Don

It's been a month and a half since I updated this thread, where does the time go???

Anyway, sometime last month after putting the torque tube in, I re-installed the rear suspension. I have some time off this week so I moved on to the next part of the engine conversion, brake booster removal, brake and clutch pedal modifications.

Wow, I am not nearly as flexible as I was in my younger days! The seat and the steering wheel are totally in the way when trying to get to the pedal mounting and fire wall. .
Here is a short video update.


It is also time to figure out a few things about the engine before it goes in.

1) Need to figure out what flywheel to put on it. I think an LS1 Camaro flywheel will work but we want a light flywheel.

2) Displacement On Demand (DOD). We won't be using DOD and it seems to run normally with the DOD solenoids unplugged. I'm not 100% comfortable just leaving the DOD parts in there, they don't have a great reliability record.

3) If we remove DOD we need to change the cam, lifters, valve springs and plug the solenoid oil holes.


-Don

Don, my son did one of these LS motor swaps into a 280Z .

The flywheel/clutch threw him for a while. If you need any assistance on that set-up PM and I'll give you his number.

Dave

Dave 1234 wrote: ↑

Tue. Feb. 18, 2020 9:37 am

Don, my son did one of these LS motor swaps into a 280Z .

Nice!
I played with 240Z cars all through the 80's. In the end, I put a Chevy 350 in one and that was it! It was an easy conversion too, not complicated like this one.

Today we removed the brake booster, modified the brake pedal pivot location and installed the brake master cylinder adapter. There were many challenges along the way so it took all day. I'll let the video do the talking!

-Don

Yesterday we started doing some engine bay prep. This is an effort to do all the little things before installing the engine and finding out you can't get to that part anymore. We are not going to run AC this year so we removed the AC lines and cut off the mounting studs on the drivers side frame rail to clear the header. Renegade Hybrids offers a compact AC kit that includes lines that run to the passengers side where the compressor is located on the LS. The original Porsche location is on the drivers side.

Here is a video discussing most of the engine bay prep.

This video shows the action of cutting the little studs off the frame and removing the AC lines.


As far as the all aluminum, L-77, 6.0 liter engine goes, we are not going to modify it very much. When your talking about LS engines it's very easy to get carried away and start buying all kinds of stuff that may not really fit your application. The theoretical potential of a cam/lifter/valve spring swap for this engine is in the 525 HP range. That might not be practical for a daily driven sports car though.

Within the scope of this project we wanted 350 to 400 horse power. The L-77 V8 is rated at 362 HP and 391 pound feet of torque with all the accessories on it. Running without power steering and AC will free up a few more HP, so before any engine mods, we have hit our target.

There is the problem of the Displacement On Demand (DOD) system though. The plan is to swap the DOD lifters out for LS7 lifters and use threaded plugs to eliminate the DOD solenoids. While we have the heads off we will swap in a set of PAC 1218 valve springs just in case we go with a bigger cam later.

While the heads are off we will look for any cam ware. If it looks good, we will run it as is. I have spent the past few months pondering a cam swap and I just can't come up with a good cam solution. The stock L-77 cam is a pretty good performer, so we will use it.
Intake lift = .478, Exhaust lift = .466.
Intake duration = 196*, Exhaust duration = 208*
Lobe center = 116*
Compression ratio = 10.4 : 1

Engine mod discussion video.


-Don

Yesterday we removed the L77 factory oil cooler and pushed forward with our DOD delete plan. The oil cooler is held on with 4 bolts and comes off real easy. It draws coolant from the side of the block and sends it to the radiator. There are two oil passages above the oil filter that lead to and from the cooler. For this install we are just going to remove the cooler because it interferes with the header and exhaust system. In this video we discuss the oil cooler, DOD delete and putting timing marks on the crank pulley.

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There is some internet information saying that you cannot use a stock Displacement On Demand (DOD) cam with non DOD lifters. My experience tells me that this claim doesn't pass the "Smell Test", so I am raising the BS Flag and pushing forward with the cam I have. We will find out who is right when we fire this engine.

Displacement on demand solenoid oil holes plugged with 1/8th" pipe plugs. Here is the video showing the DOD delete process and some discussion about internet DOD delete BS.


-Don

Yesterday we swapped in the new PAC 1218 valve springs.

I set the head on some wood with a piece of 2x4 in the combustion chamber up against the valves. This keeps the valves in place while removing the springs. Then we compress the valve spring, Tap the top of the valve spring compressor with a hammer to release the retainer and locks, Pull the locks out with a magnet, and pull the spring out. Swap the retainer onto a new spring, and put it in the spring compressor. Put it on the valve, install the locks. One down, 15 more to go! Once we got over to the second head, we ran into a little surprise...
The #3 intake valve spring came out in 2 pieces! It must have been able to hold the valve closed during our driveway test run. It ran fine with no noises. It's a good thing we decided to upgrade the valve springs, ain't it!

After the valve spring adventure, I cleaned the carbon off of the combustion chambers and piston crowns.
There ya go! all cleaned up and ready to re-assemble. Then onto the timing. LS engines don't have timing marks or pointers. Just in case we need to know when #1 is at TDC, or if we need to look at ignition timing, I made a simple pointer. Then filed a corresponding groove into the crank pulley. Here is a video of the the days progress.

-Don

I can't wait to see when this project hits the road.

lsayre wrote: ↑

Sun. Feb. 23, 2020 6:35 pm

I can't wait to see when this project hits the road.

Thanks Larry!

This week we made a lot of progress and figured out how to handle most of the challenging parts of this project. I was really dreading the brake pedal modifications, I'm glad that one is out of the way. My back still hurts from having the door sill jammed into it for several hours! No real progress today, just cleaned up the garage a bit so I could fit the VW back in. I've got a long work week ahead so I probably won't get back to this project until next week.

I was also weeding through the internet BS about these LS engines. Cylinder head bolts and how to torque them falls into this category. We are going to re-use our bolts and torque them to 25, then 65 or 90 degrees whichever comes first.

I also found out more info on the stock cams. I am even more confident that this L77 cam will work well.

I also found out something that I was not expecting, the purpose of the lifter tray. I didn't think this was an important piece at all. It turns out that the lifter tray is the only thing that keeps the lifters from turning. If the lifter turns, or moves around, the roller will no longer be strait on the cam surface. This will destroy the cam and lifter. Now I'm glad I got new tray with my new lifters! We still have some engine bay prep to finish. I want to have things like heater hoses, vacuum lines and wiring in place before the engine goes in. Once the engine is in, things will get much more difficult to work on. Last video update of the weekend.


-Don

We made some good progress yesterday. First, we cleaned up our new LS7 lifters and put them in some oil. The Renegade Hybrids conversion oil pan requires a different oil pickup. We removed the stock pickup, we also removed the windage tray to have a quick look at the bottom end. Removed the O-ring from the oil pump for reuse on the new oil pump pickup. This is the crank reluctor and crank position sensor. Inside the baffled and trap doored Renegade oil pan. There it is all ready to go! Then it was on to installing the heads.

I cleaned up the block and head surfaces. Then chased the threads. Then,,,,,

CRAP!!!!
Instead of ordering one PAIR of head gaskets, I ordered ONE gasket! Well, that put a little dent in our progress for today. We did get the drivers side head on and torqued down. We'll put the other one on when the gasket comes in. Videos of yesterdays progress. These cover oil pan install as well as lifter trays and lifters.


I also included a good explanation of the important purpose of the lifter trays.

-Don

The head gasket and some other parts came in this week! Last night we put the passenger side head on the 6.0 V8 and got the valve train put back together, it all tested good. I finally figured out how to get the oil fill off of one of these LS beasts! From inside the valve cover, using a small screwdriver, you pry a tab up and then you can turn the oil fill. Once the tab is released, turn the oil fill counter clockwise 90 degrees and pull it out. There is an O ring on the oil fill that seals it and holds it tight. After that, we cleaned up the valve covers, installed the old gaskets and installed them. Here is the video of last evening's action.


Today we will be removing the Displacement On Demand (DOD) solenoids from the valley cover. Then cleaning up the cover and installing it. Then it will be time to test run the engine one more time before it gets cleaned, painted and installed.

-Don