Is Manfield a Subaru killer?

[Flat4]

Round two of the Manfield Road and Track series is on tomorrow and I hear that the big right hander at Manfield has a reputation for killing Subaru engines.

I know there are a few members here who have run a bearing there but is it really that bad?

Risky running without a baffled sump and just a 1/2 litre overfill?

[loner]

Lot's of Subarus survive there without a baffled sump. If your on road tyres, and don't have lots of neg camber etc... just overfill it.

[Joker]

no its not a Subaru Killer, as in as much as I have heard Hampton Downs is

maybe once you start using semi-slicks then BEB's are more of a risk

ooh today? might go for a look

[Johnnynz]

I have done a few laps there and had no issues. Went to Semi slicks last time with no issues, I normally overfill a little. Dont know if that really helps or not but makes me feel better.

[Richwalk]

The PBMS sump isn't really all that costly. Perhaps move that up the priority list. I've seen many Subarus meet their demise at manfield, even 3 in one day.

[philc]

yep, with sticky tyres the g forces on the car force oil out of one side of the horizontally opposed pistons ...... clunk!

[pedro]

I am thinking it has a lot to do with the line you take through the sweeper..

Some people use a constant radius to get around and this forces the oil away from the pickup..

I have been using more of a "motorcross" line and trying to square the corner off to avoid building up the 'G' forces too much..

Managed to do three meetings with no problems with oil surge and catch tank remaining free from oil..

Might have been lucky so far but seems to work for me..

[Timmah]

Sam, I think it's time you sold the GTB and bought a V7 STi.

Wait that's not helpful.

Do it anyways.

[Rosssub]

Not only the oil sloshing out of the sump, but the time it takes for the oil to drain back in. The JDM twin scroll sump has much better internal drainage than the standard single scroll sump, getting the oil back into the sump quicker.

[B1]

A baffled sump is cheaper than an engine rebuild IMO

[Joker]

except when its the tip of the iceberg of modifications

as in, Brakes, suspension, heck when the sumps of why not close the block, bigger injectors, parallel fuel rail mod, bigger turbo, ECU... and so on and so on

on road tires you 'should' be fine, bar a few variables like service history, age of you car etc, mod's/tune etc (winding up the boost for the track is not recommended)

Edited June 24, 2014 by Joker

[BD5_RS]

Anybody got theories or experience with choosing a higher gear (than what may be considered optimum) through long sweepers to avoid BEB issues?

As in to reduce the speed of the oil pump, and thus reduce the chance of emptying the sump and causing starvation.

[Joker]

Left hand corners re worst iirc cos poor draining back to sump (left hand head is catcher

[Rosssub]

The oil pump can't pump that fast, or be slowed down by engine revs. It has an internal relief valve that opens/closes to maintain oil pressure.

It's the sideways G-forces from cornering that empties the sump, like holding a glass full of water and spinning around in circles.

[Dacca]

 B1 said:

A baffled sump is cheaper than an engine rebuild IMO

All EJ20T sumps are baffled. You need more capacity and for it to be gated.

[BD5_RS]

 Rosssub said:

The oil pump can't pump that fast, or be slowed down by engine revs. It has an internal relief valve that opens/closes to maintain oil pressure.

It's the sideways G-forces from cornering that empties the sump, like holding a glass full of water and spinning around in circles.

I realise the main culprit is the oil moving away from the pump pickup, but to expand your analogy; at the same time you've got a straw in that glass sucking away as well (sending oil through the galleries).

I was more considering the oil flow required by the engine at high rpm to maintain a safe pressure, versus the oil flow required at a lower rpm, and whether that could be the difference between BEB failure and BEB success under any circumstances. At high rpm the forces acting on the bearings are less sympathetic to low oil pressure than at low rpm.

[Tony]

 BD5_RS said:

Anybody got theories or experience with choosing a higher gear (than what may be considered optimum) through long sweepers to avoid BEB issues?

As in to reduce the speed of the oil pump, and thus reduce the chance of emptying the sump and causing starvation.

Using a higher gear means you should be using less revs when going around that corner... and people do this for exactly the reason you mention just above: "At high rpm the forces acting on the bearings are less sympathetic to low oil pressure than at low rpm"

(Generally, you find that most people driving Subarus would use 3rd gear to go around that particular corner at Manfeild).

[Guest]

If youre really worried probably throw in a full syn oil as well. Better film strength, better with heat, better base oil more uniform molecules reduces friction etc a lot to it but regardless if its on the ragged edge the synthetic improves your chances.

[Joker]

yea but that's not good if your previous service history is crap/5000kms overdue with blocked galleries

then all of a sudden "oh Manfield killed my car"

in saying that, that is not bad advice a few weeks before you hit the track

[Zach]

I thought stock wrx sumps were baffled?

[Joker]

thats whats Dacca says further up the page

[Richwalk]

Has anybody thought about adding one of these into the Oil system?

http://www.jegs.com/i/Moroso/710/23900/10002/-1

Wondering if it would help...

[Joker]

Pretty much only good for cold startups (apply pressure instantly) doesnt stop starvation at high G's at the pickup point I beleive (good find tho)

edit just read the product description : I am so wrong LOL, seems like it should be ideal , except for the extra 2 or so liters of oil it takes to fill it

(mate had one in his Small Block Chev Celica race car running on a Link) = real world experiance

Edited July 13, 2014 by Joker