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3rd gen bogging in turns and losing oil?

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Old 09-02-07, 03:09 PM
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3rd gen bogging in turns and losing oil?

Guys,

Just been to a track (well, silverstone if you must know, driving the F1 GP track) and i have a little problem.

I thought the car was pretty well prepared but it seems maybe it wasnt! and im not sure what to do to fix it.

this post is asking two questions really..

First off, when i left home this morning, i had a full sump of oil. Out on the track after the first 15 minute session i noticed that right infront of my BOV there was a load of oil (i figure this is normal, oil working its way up the filler neck and into the breather right?)

The thing is, theres also loads of oil around the side of the engine with the filler neck on it...its all over my leads, plugs, even on stuff just below the TB...i guess i must have a leak? or is it normal for them to leak oil here under hard cornering?

So yeah, i guess what im asking is A) can i just block off the oil breather system? I have a baffled filler tube but i guess it couldnt quite do the trick. Or do i get a catch can?

After the second sesion i had just under half a sump of oil, and through the turns i noticed i was getting low oil pressure (needle bouncing on my defi, measured at the filter pedestal)

Can i get a sump baffle or similar? Do any of you guys run these?


Second question, is bogging in the turns.

When i was really going flat out through sharp long turns, the car would bog terribly, to the point where i was going round one turn ( a left hander) completely sideways (it was a car show, the crowd like it...) and the car bogged and lost power so terribly it flicked me the other way and nearly off the track. I had about 3/4 of a tank of fuel at the time, and i had the "bouncing" oil pressure problem.

I noticed this alot on turns with high lateral G's and its very annoying. Generally it happens more when im at equal throttle (if i floor it it tends to go away)

I originally thought fuel starvation but surely not with such a full tank? Has anyone else had this problem?

Specification of my car is as follows (excuse non relevant bits, cut and paste spec...)

8000 miles on engine
polybushed rear and diff
18 inch rays 57s pro wheels with michlin pilot sport 2 tyres
K-sport coilovers
AP 330mm 6 pot brake kit with grooved rears
Re-Amemiya vented bonnet
Re-Amemiya flush lights
cobra buckets & harnesses
Stillway uprated intercooler
baffled oil filler tube
alloy race rad
non silenced de cat mid pipe
feed downpipe
greddy intake elbow
apexi air filters
defi gauge cluster (oil pressure, temp, water temp, boost)
Apexi PFC
Odysee PC680 battery
Alloy hardpipes
15psi boost

thanks guys!
Old 09-02-07, 08:01 PM
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The oil fill neck needs a new o-ring or some silicone gasket stuff at the junction that attaches with the two bolts.

If the power loss is not extremely dramatic it could be the check valve to the pressure tank. If it's dramatic (fall on your face type loss) it's fuel starvation and you probably need a pump.
Old 09-03-07, 04:08 AM
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I caked the bloody thing in silicone when i installed it about two weeks ago though! Not to worry about that though, its something i really need to have a look myself - you cant tell me where my car is leaking...

re: the power loss though, it is dramatic, fall on your face power loss (When its really bad)

Why would it be only in turns though? My fuel wasnt low enough to cause it so why would the pump give out in the turns? I also noticed from the videos my friend took that i was getting some pretty huge flames out the back as the car was losing power if this helps...

I guess ill try a new pump, but my brain is telling me its not that...otherwise itd be happening in the straights too right?
Old 09-04-07, 08:51 AM
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Originally Posted by BobfisH
I caked the bloody thing in silicone when i installed it about two weeks ago though! Not to worry about that though, its something i really need to have a look myself - you cant tell me where my car is leaking...

re: the power loss though, it is dramatic, fall on your face power loss (When its really bad)

Why would it be only in turns though? My fuel wasnt low enough to cause it so why would the pump give out in the turns? I also noticed from the videos my friend took that i was getting some pretty huge flames out the back as the car was losing power if this helps...

I guess ill try a new pump, but my brain is telling me its not that...otherwise itd be happening in the straights too right?
You're right it's probably not the pump and I can't tell you where your car is leaking oil so just take a look at it yourself.

Good luck
Old 09-04-07, 09:56 AM
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My 2 cents:

I think Fritz is correct. I'll bet the oil is leaking either from the oil filler tube connection or possibly through the fitting on the oil filler tube. I'm assuming you are running one of ReSpeed's oil filler necks? Where do you have the nipples plumbed to?

Even with a baffled tube, you will get some oil getting past. I would recommend a catch can to work in conjunction with the baffled filler neck.

As for the cutting out, it sounds like a fuel issue. It's not uncommon for the car to loose fuel pick up on corners when the tank is below 1/2, especially with some sticky tires. You might check this:

https://www.rx7club.com/group-buy-center-69/re-opened-fuel-surge-cover-gb-682991/
Old 09-04-07, 09:22 PM
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Originally Posted by Fritz Flynn
The oil fill neck needs a new o-ring or some silicone gasket stuff at the junction that attaches with the two bolts.

If the power loss is not extremely dramatic it could be the check valve to the pressure tank. If it's dramatic (fall on your face type loss) it's fuel starvation and you probably need a pump.
Sounds very familiar! I had the same issue on my car that I sold to Fritz
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