Plavan's 818R Build Thread

[DMC7492]

Hi Chad, you mentioned the high water temps and the engine bay heat softening the vacuum lines. Installing the coils to support the hose is really band aiding the root cause.
The heat is still the cause.
Can you run with the lower engine shield off for a test run?
Can you as mentioned above test a larger radiator?
I'm thinking the air flow through the heat exchanger and then through the radiator is not dropping the outlet temp enough.
Remember the factory WRX cooling system only has three feet of radiator hose and the 818 has what about twenty five feet of tubes?
Or the flow rate through the cooling system has slowed due to the length of tubing.

[C.Plavan]

Hi Chad, you mentioned the high water temps and the engine bay heat softening the vacuum lines. Installing the coils to support the hose is really band aiding the root cause.
The heat is still the cause.
Can you run with the lower engine shield off for a test run?
Can you as mentioned above test a larger radiator?
I'm thinking the air flow through the heat exchanger and then through the radiator is not dropping the outlet temp enough.
Remember the factory WRX cooling system only has three feet of radiator hose and the 818 has what about twenty five feet of tubes?
Or the flow rate through the cooling system has slowed due to the length of tubing.

I'm hoping once the oil situation is solved, the other things will magically fix themselves. I believe the primary problem is the oil, if it not, I'll be ditching the undertray or adding NACA ducts to it.

[bbjones121]

When is the next race?

[bbjones121]

Do you think you could do a string test with some of your vents on your car and video where the strings go when you are driving

[C.Plavan]

Do you think you could do a string test with some of your vents on your car and video where the strings go when you are driving

Already did that. Its a few pages back. In a nutshell, they work like they should (Except the rear top trunk vent was sucking air in).


I'm in no hurry with the 818 for the next track day. I'm racing this beast on Sept 5th, 6th. There are a few things I need to prep before.

[Pearldrummer7]

That's awesome. Specs on the Porsche? What class do you race?

[Frank818]

Already did that. Its a few pages back.

I don't see you testing the top side vents of the humps lid.
At least not on page 34 where you test many other vents.
Have you tested them?

[bbjones121]

I don't see you testing the top side vents of the humps lid.
At least not on page 34 where you test many other vents.
Have you tested them?

Those are what I am interested in

[longislandwrx]

There's really nothing left of those vents on the R... the downtube goes right through them.

wuwutWXl.jpg

[Mechie3]

He means these vents:

[Pearldrummer7]

Those vents pass the "looks awesome" test, at least.

[Frank818]

I personally meant those that longisland-NY-Rangers showed up. I didn't know the downtubes were at a different angle than on the S, never realized that before. But there is still an opening, not sure of its efficacy though.

[Zach34]

Chad, got a quick question for you taking a tangent from current topics: How is the elbow room on the left of the seat? I have almost the same seat as you, and I noticed after I got my steering rack/column bolted in last week that the lack of elbow room between the frame and seat on the left side might be problematic. I haven't gotten a steering wheel yet - just using the OEM wheel for test-fit, which is much larger and deeper-dish than the aftermarket steering wheel I will get. An aftermarket wheel should help.

Is it a problem on the racetrack? Do you find yourself wishing you had maybe modified the cage there?

[C.Plavan]

Chad, got a quick question for you taking a tangent from current topics: How is the elbow room on the left of the seat? I have almost the same seat as you, and I noticed after I got my steering rack/column bolted in last week that the lack of elbow room between the frame and seat on the left side might be problematic. I haven't gotten a steering wheel yet - just using the OEM wheel for test-fit, which is much larger and deeper-dish than the aftermarket steering wheel I will get. An aftermarket wheel should help.

Is it a problem on the racetrack? Do you find yourself wishing you had maybe modified the cage there?

It's not bad. I don't notice it on the track. The only time I notice it is when I'm putting my belts on before going out on the track. I'm not using a door panel on the drivers side, but I have a real metal intrusion panel (not the thin flimsy FFR one) on the outside of the cage. It's as tall as the last horizontal top cage bar, so I have a little room between the top of the door, and that bar for my elbow when strapping in. I think I nudged my seat to the center just a bit. It's easy to do with the racing seat brackets.

[Zach34]

Thanks. I'm at the point where I need to make sure I don't want to make any more drastic changes to the frame. I'm not sure I could modify the cage without causing tech issues, anyway.

[philly15]

purely out of curiosity, are you using a td04 on your car?

[Hindsight]

Hey Chad, any tips on checking oil levels? I figured you'd be the best person to ask since you have so much external capacity. I don't have a dry sump and tank like you, but I do have -10 lines going to a big external oil cooler. The lines to the cooler go up, and then down to the cooler and the cooler sits higher than the oil pan. I am wondering how much oil is flowing back into the pan when the engine is off, affecting the readings.

Also, how long does it take for you to see oil pressure after you start? I don't see pressure on mine for ~3 seconds.

[C.Plavan]

Hey Chad, any tips on checking oil levels? I figured you'd be the best person to ask since you have so much external capacity. I don't have a dry sump and tank like you, but I do have -10 lines going to a big external oil cooler. The lines to the cooler go up, and then down to the cooler and the cooler sits higher than the oil pan. I am wondering how much oil is flowing back into the pan when the engine is off, affecting the readings.

Also, how long does it take for you to see oil pressure after you start? I don't see pressure on mine for ~3 seconds.

Mine is pretty much instantaneous with the dry sump set up. With dry sumps, you check the oil level when running in most cases. In your case, I would run the oil a lot higher depending on your oil cooler size (extra quart or so- depending on the size of cooler). Everything will settle in the pan after sitting (depending on your oil line run).

Where is your pressure gauge sender located? (Near Alt?) 3 seconds sounds like a lot. What brand of gauge?

[Hindsight]

Thanks. My gauge sender is located in the stock spot, right next to the alternator. It's a prosport electronic. I have a mechanical gauge on order now and am going to swap out the electric sender for the mechanical one to rule that out. If there is still a delay, I will remove the Mocal sandwich plate and run the oil filter right on the block to see if that doesn't make it faster. If that makes it faster I will have to try to figure something out to keep oil from draining back from the cooler. The cooler is higher than the oil pan, but in order for it to drain, wouldn't air have to get in? It can't pull air in from the pump, and on the other side it goes to the galleys that feed the journals and heads so I'm not really sure where the air would come from. At any rate, if drain back is the issue, I guess I need a one-way check valve in the line sending oil TO the cooler from the block?

[Scargo]

You should have an anti-drain back valve in the oil filter. These have been known to fail or leak. The oil pump does not provide a seal, nor does it have a check valve.
Having said that, if the oil cooler is higher than the oil level then it wants to empty and you must have a seal on one end or it will empty itself from gravity or from siphoning. If you have a good seal at the filter then a loss of suction could occur if you have "enough" air in the oil lines or oil cooler. This might occur if you have the cooler mounted in such a position where air could be trapped.
A small leak, anywhere in the circuit, could allow the suction to fail and the oil to drain out (of at least one of the cooler hoses). I think you would eventually see that leak as oil gets out under pressure. Certainly variations in heating and cooling and pressure or no pressure can affect whether there is a seal, though I've seen this mostly occur in water cooling systems.

[Mulry]

FWIW, Peterson recommends not putting a check valve in the system due to the potential for causing cavitation in the oil pump:

http://www.petersonfluidsys.com/tech_faq.html

Hindsight, I'm not sure of your setup. Are you running an Element-type dry sump that is scavenge pump only with the factory oil pump, or are you running a dry sump pump with pressure section? If it's the latter, you can just remove the drive belt and run the dry sump pump with your electric drill for 10 seconds to pressurize the system prior to firing the engine. If it's the Element system, then you can't run the oil pump separate from the crankshaft, so you might want to think about using a small 1qt Accusump just to pressurize the oil system prior to start.

[Hindsight]

Thanks for the reply guys. I don't want to hijack Chad's thread though.

After starting the car and letting it full warm up (which should have completely filled the lines to the oil cooler), I get oil pressure much faster now. ~3 seconds or so from start. So I think I'm ok. Thanks again for the replies.

[C.Plavan]

Long time no update. I raced the 911 and had a blast. It's nice to have a fully functional race car where you do not have to watch gauges like a hawk. The 911 was only 2 seconds slower than the 818 on the same race track configuration :/. I ended up getting 1st in class in all races with 2 overalls (out of three).

I installed these spiral metal springs into new -12AN scavenge oil lines. They will keep the lines from collapsing under vacuum when they get hot, or keep them from kinking in bends. I can step on them and they don't collapse, now I hope that this was the problem.


I rerouted one scavenge line farther from the header, and will make another heatshield to be safe. I'm going to tighten the oil pump belt a little more, then it is time for another test.

[bbjones121]

Best of luck.

[Flamshackle]

hoping for the best mate.

[C.Plavan]

As an added bonus- Look who will be out at the track the same weekend with us I just hope everything works right because it will be a great way to compare cars. Maybe I will sneak out in their practice session for fun. I really need a flat rear wing.

[bbjones121]

As an added bonus- Look who will be out at the track the same weekend with us I just hope everything works right because it will be a great way to compare cars. Maybe I will sneak out in their practice session for fun. I really need a flat rear wing.

Sweet! I can't wait to hear how it goes!

[Mulry]

Wow that car is low in front. Wouldn't need more than one reminder to stay off the kerbs.

[JeromeS13]

Good luck! Those things are crazy fast (with a skilled driver).

[Scargo]

That will be fun! The Lotus cockpit cover is what I'd like to emulate. That and a flat wing.
That Lotus must have its suspension pretty compressed in that shot.
Was really disappointed to hear that John George was not able to drive the FFR 818R at Palmer this past weekend. The Electromotive ECU was acting up and I don't think he got in any time on the track with it. BTW, that gray car has power steering!
FFR gray 818R.jpg

[Mulry]

That #5 test mule appears to have the front of the humps open, which probably does wonders for lowering engine bay temps, but could impose a nasty aero loss. GT-1000 wing?

[C.Plavan]

That #5 test mule appears to have the front of the humps open, which probably does wonders for lowering engine bay temps, but could impose a nasty aero loss. GT-1000 wing?

I cant tell you it does not do anything. I tried them open.

[Bob_n_Cincy]

That will be fun! The Lotus cockpit cover is what I'd like to emulate. That and a flat wing.
That Lotus must have its suspension pretty compressed in that shot.
Was really disappointed to hear that John George was not able to drive the FFR 818R at Palmer this past weekend. The Electromotive ECU was acting up and I don't think he got in any time on the track with it. BTW, that gray car has power steering!
FFR gray 818R.jpg

I cant tell you it does not do anything. I tried them open.

Chad,
it looks like no windshield, so they may be getting some air in the passenger hump.
Bob

[D Clary]

Looks like larger side scoops and vents on top of the quarters. I wonder if they would share any of these pictures close up with explanations as to how they work.

[Frank818]

You've got to beat that Lotus.

[C.Plavan]

You've got to beat that Lotus.

They are in a different all Lotus run group. We can compare times..... just hope car works.

[C.Plavan]

Chad,
it looks like no windshield, so they may be getting some air in the passenger hump.
Bob

Yeah- But I tried it. I originally had my air filter there (in the open hump) It still did not get much flow. In fact, when I had the humps open and my coolant overheated, coolant was spewing out my overflow (which is behind the degas tank) from the hump forward in a circular buffeting motion. It got my dash and fuel cell cover wet at speed....... I'm telling you this car is possessed.

[C.Plavan]

Here is a video from my last Vintage race. The video is from a ~600HP Camaro. He has a great rear camera setup. You will see the difference between a Drag racer and a race car (My car @211 RWHP- 2.5L short stroke). The other car is a Canterham kit car. ~260 hp weighing 1000 pounds. The thing was ridiculously fast.

https://youtu.be/QeG20UkxlDE

[Hindsight]

Is it just me or is that Caterham not going nearly as fast as he could through those turns? On most every turn, he straightens out on the inside of the track almost immediately after the apex.... no drifting to the outside edge. With his power to weight ratio, I would think he isn't power-limited there. Maybe he's just late-apexing and I can't see it from this camera angle?

Sure does look like fun. I can't wait to get my 818 into some HPDE days.

[C.Plavan]

Is it just me or is that Caterham not going nearly as fast as he could through those turns? On most every turn, he straightens out on the inside of the track almost immediately after the apex.... no drifting to the outside edge. With his power to weight ratio, I would think he isn't power-limited there. Maybe he's just late-apexing and I can't see it from this camera angle?

Sure does look like fun. I can't wait to get my 818 into some HPDE days.

Yeah- I could not figure out his line. I'm hanging on for dear life on exit. A car that light with that much power just proved he can go anywhere on the track no problem. He was in a different class. He ended up doing my 818R time. My 911 was 2 seconds off of it. Regardless, still impressive.