964 C4 light refurb
#136
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Thread Starter
With the car on stands, assuming you have disconnected all of the items (directions in the Porsche workshop manual or Adrian's book) you are ready to drop the engine/box.
I placed the ATV Jack under the engine with the ridge in the routered slot. I made two mistakes here:
1. My ATV Jack had insufficient reach so the car wasn't high enough (I had to raise the body after the engine mounts were disconnected, which isn't easy) and
2. I didn't think to fix the plywood to the jack, which allows the motor to move, not much but you want the motor to stay centered.
I placed the ATV Jack under the engine with the ridge in the routered slot. I made two mistakes here:
1. My ATV Jack had insufficient reach so the car wasn't high enough (I had to raise the body after the engine mounts were disconnected, which isn't easy) and
2. I didn't think to fix the plywood to the jack, which allows the motor to move, not much but you want the motor to stay centered.
Last edited by John McM; 12-13-2015 at 03:42 PM.
#137
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Thread Starter
Assuming the engine weight is taken by the ATV lift you can slowly lower the engine. Use the AC Jack or race Jack to support the weight of the transmission. Roll the two out the back of the car. A C2 box would be easier than a C4 as there is less to disconnect and the box is shorter and lighter.
#138
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Thread Starter
As you put the front wheels on the planks you should have enough room to lift the front of the car, if desired, by putting a plank under the front or rear ridge of the tub (not the middle as you would be lifting on a less supported frunk floor) and lift it on to front stands. This is child's play with the AC Jack. If you didn't use the planks there is no way a Jack will get under the tub.
Last edited by John McM; 12-13-2015 at 03:44 PM.
#139
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Thread Starter
When you are ready to refit the engine and box, you just roll the engine and box in on the ATV lift and lift it into place. If your lift doesn't enough height you will have have some fun. We lifted the front of the car to bring the car closer to the Jack height.
Otherwise the only special tools I had to buy were the 32 and 36mm spanners and a set of hex sockets. I also made a torque tube holder.
Otherwise the only special tools I had to buy were the 32 and 36mm spanners and a set of hex sockets. I also made a torque tube holder.
#142
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Thread Starter
Thanks John. I am chasing down those last two spare pipes. I think they are both normally connected to the air filter housing. The large one looks like the connector to the charcoal canister under the left rear wing. Once those are done, I'll fit the heater fan and SC air filter. Then I'll sort out the heater hoses and starter connections. Moving my way forward. There's a bit of fettling required on the splitters but they look damn good. I also need to source a captive but for the headlight screw. Small things but getting there.
#143
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Thread Starter
Pipe homes are found:
1. The large one connects the gas/petrol vent to the air intake.
2. The thin one connects to the vacuum reservoir attached to the air intake.
I installed a Specialist Components system which has a simple intake. There is no intake connection to the tank vent and I can't recall the instructions mentioning the vacuum reservoir either.
The impact of the small vacuum line is significant as the reservoir supplies vacuum to the resonance flap that gives our cars a kick above 5,500 rpm. The attached chart has a race engine dyno plot for flap and no flap which shows the impact. Between the cat bypass and this find I'm hoping for > 30 hp before I take it to the dyno
1. The large one connects the gas/petrol vent to the air intake.
2. The thin one connects to the vacuum reservoir attached to the air intake.
I installed a Specialist Components system which has a simple intake. There is no intake connection to the tank vent and I can't recall the instructions mentioning the vacuum reservoir either.
The impact of the small vacuum line is significant as the reservoir supplies vacuum to the resonance flap that gives our cars a kick above 5,500 rpm. The attached chart has a race engine dyno plot for flap and no flap which shows the impact. Between the cat bypass and this find I'm hoping for > 30 hp before I take it to the dyno
#144
Rennlist Member
Thread Starter
This is my (limited) knowledge of the resonance flap.
There are two horizontal plenums in the intake, one above the other.
Below 5,500 rpm the lower plenum is closed by the resonance flap. This gives better low rpm power.
At 5,500 rpm a solenoid trips (the noise 964 owners should hear on initial start-up where the DME cycles the valve), releasing the vacuum held in the reservoir to operate the flap valve.
This allows air to flow in both plenums. I think this is a forerunner to the 993 varioram system where changing the intake length changes the torque/power output. Obviously the 964 is a bit cruder because it's on/off.
My issue is that I have no vacuum reservoir hooked up so the flap doesn't move. I will remove the reservoir from the air intake and mount it securely so it can be hooked up again.
There are two horizontal plenums in the intake, one above the other.
Below 5,500 rpm the lower plenum is closed by the resonance flap. This gives better low rpm power.
At 5,500 rpm a solenoid trips (the noise 964 owners should hear on initial start-up where the DME cycles the valve), releasing the vacuum held in the reservoir to operate the flap valve.
This allows air to flow in both plenums. I think this is a forerunner to the 993 varioram system where changing the intake length changes the torque/power output. Obviously the 964 is a bit cruder because it's on/off.
My issue is that I have no vacuum reservoir hooked up so the flap doesn't move. I will remove the reservoir from the air intake and mount it securely so it can be hooked up again.
#145
Rennlist Member
Thread Starter
A lot of progress tonight. Anti roll bar in, bottom panels on, cat bypass (with new O2 sensor bung), cup pipe and secondary exhaust on. Rear reflector on. Heater pipes in, finished off by putting the car on its wheels with 20 new shiny lug nuts. Now to let things settle before the final torquing of mounts, arb etc
#148
A lot of progress tonight. Anti roll bar in, bottom panels on, cat bypass (with new O2 sensor bung), cup pipe and secondary exhaust on. Rear reflector on. Heater pipes in, finished off by putting the car on its wheels with 20 new shiny lug nuts. Now to let things settle before the final torquing of mounts, arb etc
Wow John, Just wow. Looks absolutely gorgeous!
#149
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Thread Starter
Originally Posted by C4inLA
Camera playing tricks on us, jack stand can't be leaning that much in second to last pic?
#150
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Thread Starter
Originally Posted by racoguy
Wow John, Just wow. Looks absolutely gorgeous!