m2cupcar

iTrader: (5)

race car rule of thumb is 10psi for every 1000 rpm. You're just short of that if you're seeing 4bar at 6k - but you're also using the stock gauge AND you're not racing. I would be comfortable with what you're seeing- and you've got improved temps (I'm assuming).

beerslurpy

Hmm I've never had warm pressures that high. I'm using an electronic sender autometer gauge.

I get 50+ psi cold idle.
12-15 psi idle warm.
Max of 50-55 psi or so when warm.
Max of 40-45 psi in the hottest part of summer.

I'm currently running 10W40 if I remember correctly. I have run 15W50 in the past but I stopped, for reasons I can't recollect. Maybe I wasn't able to find any at the store. I have stuck with mobil 1 synthetic for years.

beerslurpy

Also, if you guys are willing to wait a little bit for all my parts to arrive, I will have a new post with complete parts list, pictures and instructions for doing a cheap and high capacity oil cooler/remote mount setup that uses the tru-cool 24 row cooler and ford mustang v8/2.3T oil filters. Total cost including fasteners, tubing and all parts is still well under 200 shipped and finished.

Mounting point of the cooler is under the hood latch and oil filter is mounted behind the front fender, in front of the passenger side wheel.

beerslurpy

From spec miata forum, from "Bob Thornton - Race Engineering"

qes78

Ah, Thanks for the replies.
My oil pressure hits about 40 kg/cm2 when at high rpms.
Seems to be alright. Help has been greatly appreciated

m2cupcar

iTrader: (5)

Keep in mind that when building a race engine for max power, longevity is sacrificed. I should have made my race car statement in context - that was for an club racing engine intended to race a few seasons. A "loose" engine makes more power at price of excessive tolerances that produce premature (again relatively speaking) wear. So in "our" environment it would probably be wiser to yield to more pressure in the interest of preservation, rather than running less for a few more hp.

Probably an important section to note also:
All of this is dependent on oil types and other variables.

Just a thought - you have a comment coming from an engine builder who builds incredibly powerful "stock" engines. What's the likelihood of accurate information coming from somebody who's success and livelihood rely upon trade secrets? For example, we were dyno tuning an ITA Miata which made 116rwhp. When asked how that compared to an off the shelf RE SM engine we were told that it was "in line" by a "representative". When we got to the track we asked an SM racer what they're fresh RE engine dyno'd at an were told 125rwhp.

beerslurpy

No argument there. I would rather my engine last forever than make another 5 hp from oil pump power losses.