4age oil pressure question

[xero]

ive got a built smallport in my AE86. now the question is there any issue with oil pressure are high revs.

im running an autronic, have large duration cams (around the 300 mark) 12:1 comp.
it has the factory oil pump, but i was wondering with that many revs will their be oil pressure issues?
would it be worth fitting a restrictor to keep oil pressue up (HKS make one and its about $80) under this load?
would most of the oil go straight to the head and stay there (ala RB26)??

the reason i ask, is ive had oil starvation to the head once before (not this head) with destroyed one. this wasnt due to major revs though, it was using a crappy just jap oil cooler kit..

[Casey-G]

There is a pressure relief valve upgrade you can do, its just a new spring to replace the current one in the oil pump, pretty much just to make sure pressure doesn't drop off doing truckloads of revs.


I'm not really into high comp, high revving NA 4ag's so i really dont have much else to add

hope it helps a little though

[rick q]

Unless you're hoping to pull dramatically more revs than standard - why touch the factory original?

The pressure relief valve is working from whatever revs your oil pressure peaks at (in mine from about 3000 rpm, the pressure sits on about 380kPa)

Cams and ECU's don't affect oil pressure. Engine condition, oil level and G forces are the things that will.

[xero]

thats what i was thinking, will revs + cornering g = boom?

currently its got good pressure, but im thinking preventative maintenance rather than cure after the fact.

[the_random_hero]

Have you modified the sump to prevent oil pickup starvation? I would also be hooking up a drain-to-sump catch can system so you don't end up dumping oil straight into the intake manifold.
You don't need to fit restrictors in the head.

[TERRA Operative]

Using a smallport head (or modifying the bigport head) with the extra oil drain will help prevent oil pooling in the head.

The oil pressure upgrade mod can be done with just a small washer.

Also, check out http://www.crank-scrapers.com/prod01_B.html for some nice windage trays and crank scrapers. The teflon scrapers look nice, and the windage trays are beneficial at high RPM.

Also, smoothing out all the sharp edges in the oil pump will help reduce pumping losses and improve flow too. Just don't tough the actual pump gears themselves.

[rick q]

The most common engine in Clubmans is the 4AGE - most of which are pretty standard, though some are very serious.

Most of us simply overfill the oil by about 5mm [above the "full" mark], - and it's rare to hear of any problems.

My smallport had 82,000k on it when I swapped for a 20V to get a few more h.p. It still had normal oil pressure and blew no smoke. The 20V was completely rebuilt - but the oil pump and relief valve left as Toyota intended.

Clubbies probably pull higher G's than your AE86 - Just overfill slightly and use quality oil.

[trdee]

I have noticed my oil pressure will drop when pulling high revs for long durations. Say, on the straight at wakefield heading up to the top of third. Drops about a bar on the factory gauge which = nfi pressure.

Stock bigport gze + 164mm crank pulley. Penrite HPR10