FA20 Engine Oiling, Bearings, and Starvation

[Element Tuning]

I beg to differ after grinding on the OEM 4th gear. The metal is extremely soft and I bet a straight cut, high quality gear, and a dog engagement would handle what most would need. I bet you could even get away with stock 5th and 6th for most people.

I'm currently geared to run mostly 5th and 6th gear. We'll see what happens as I'm willing to up the power in 5th-6th to see what it will handle when I have another spare trans. LOL!

[Ultramaroon]

Originally Posted by Element Tuning

The metal is extremely soft...

Hmmm... interesting.

[cdrazic93]

Originally Posted by Element Tuning

I beg to differ after grinding on the OEM 4th gear. The metal is extremely soft

The hell is it made of, pure sodium?? To the point at which it just liqufies like mercury...

[Element Tuning]

Originally Posted by cdrazic93

The hell is it made of, pure sodium?? To the point at which it just liqufies like mercury...

It might be on par with other oem gears but when I asked what's it like trying to grind down a PPG gear, I was given that look like, "please that would eat your grinder." I was shocked how quickly I was able to grind the teeth off.

[Darryljr11]

Originally Posted by Element Tuning

I beg to differ after grinding on the OEM 4th gear. The metal is extremely soft and I bet a straight cut, high quality gear, and a dog engagement would handle what most would need. I bet you could even get away with stock 5th and 6th for most people.

I'm currently geared to run mostly 5th and 6th gear. We'll see what happens as I'm willing to up the power in 5th-6th to see what it will handle when I have another spare trans. LOL!

Now to find someone who can do that for me lol

[spitfire481]

Originally Posted by Darryljr11

Now to find someone who can do that for me lol

One day. It's been a few months since we sent our spare trans out. They have better bearings figured out to help keep flex down (they said the oem were weak and would cause flex under power), better synchros to help with high rpm shifting, and stronger gears with better high hp ratios. We are gearing for a 26" tall rear tire, 3.73 diff, 8k rpm shift point. There has been progress, but it's slow since it's all custom until it's together and I try to break it

[xwd]

Chalak was working on a replacement dog gearset, but the history with those products isn't great.

[Spartarus]

Originally Posted by rice_classic

Is the pump not a positive displacement pump? Or that it's just that low of an output?

It is a positive displacement gear-type pump.

Originally Posted by Andreas83

Found some info on the reimax pump gears on a uk forum.
Theoretically they should flow more oil based on the measurements he has done.
http://www.gt86.org.uk/forums/topic/...details/page-2

I have a set on order.

Let me expand on this

The capacity of each pocket on the stock pump is 1.1cc whereas the Reimax is 1.6cc. The Reimax pump has only 9 pockets (8 teeth) compared to the FA20's 12 (11 teeth). The Reimax unit displaces 1.2cc more oil per rev. That would work out to an extra 6 litres of oil per minute at 5000 RPM.

I have a few ideas about the stock pump. The tooth count on the stock pump is 11, and the FA20DIT WRX pump also has 11 teeth (12 chambers, 12 "strokes" per rev)

assuming the differences in the tooth profile are negligible in terms of volume, the FA20DIT pump's added thickness would increase displacement volume by 16.67% meaning the DIT pump would still only move 1.283 cc of oil per pocket. The reimax pump displaces 41.67% more oil than stock, and 31.7% more oil than the DIT pump. This alone could solve all the oil flow problems.

Note: I'm working with an assumed volume for the DIT pump... It must be pretty damn close though. If @Element Tuning still has a DIT pump sitting around, could I trouble you to measure the volume of one of the pockets?

TL;DR The aforementioned Reimax pump flows significantly more oil at any RPM than both the stock and the WRX DIT pumps.

Additionally, higher "stroke" rate in a positive displacement pump contributes (eventually) to cavitation. I doubt the stock pump is cavitating even at the high RPM numbers @Element Tuning is shooting for, but it's a possibility. Fewer pockets/teeth on a gear-type pump should improve this condition at any RPM... If it's even a factor.

Anyway, I'm going to go buy one and document my results. If somebody else gets there first, please share... Money isn't flowing as fast as I'd like; the turbo and massive heaps of associated parts are slowing me down.

[BatStig]

@Spartarus thank you for getting this wonderful thread back on track! Between you and @Andreas83 I can't wait to see how the Reimax gear works out.

[D K]

^^^

Per rev of the crankshaft or per rev of the oul pump?

Do they turn at the same speed??....

[Spartarus]

Originally Posted by D K

^^^

Per rev of the crankshaft or per rev of the oul pump?

Do they turn at the same speed??....

The pump runs directly off of the crankshaft without reduction gearing. Pump rpm = crankshaft rpm.

By the way, Here's a few images for comparison and a volume testing shot. Thanks Nige.

[Element Tuning]

I have a new test engine to go into our race car that I will be testing some new parts along with maybe a tweak or two to try for more oil pressure. If people want me to test the Remax, send it to me and that will be cheaper than someone tearing their motor down only to be disappointed if it doesn't work. These mods or this pump will be my last attempt at this before going all in on the external pressure pump.

I tested the 14mm DIT pump and it really didn't do much. The design ramps up the oil pressure faster but it really dropped just like oem so the small volume improvement wasn't adequate.

The only things that worked are our engine build with internal mods, oil cooler, higher viscosity, and for 8k rpm+ the accumulator.

[themadscientist]

Does the FA20 have trouble with gears shattering or is the primary concern volume? Messing with RB26s makes me rone to worry about this sort of oil pump.

[Spartarus]

Originally Posted by themadscientist

Does the FA20 have trouble with gears shattering or is the primary concern volume? Messing with RB26s makes me rone to worry about this sort of oil pump.

No reports of that, primarily a high power, high-RPM volume/flow concern.

Originally Posted by Element Tuning

I have a new test engine to go into our race car that I will be testing some new parts along with maybe a tweak or two to try for more oil pressure. If people want me to test the Remax, send it to me and that will be cheaper than someone tearing their motor down only to be disappointed if it doesn't work.

I have a set coming next week. My rudimentary math seems to indicate this volume increase is huge compared to the 14mm DIT pump.

As far as timing chain cover removal and replacement, the manual indicates 14 replacement o-rings and the removal of the VVT sensors and camshaft oil control valves. It seems, though, that the vvt sensors and valves can stay on the cover for removal, reducing the number of replacement o-rings to 6. Can anyone confirm? I can have the replacements here before the pump.

I'm planning on doing the install myself, and I'll be set up to measure pressure at the mains. I intend to test pressure and temps both before and after the turbo install.

My main concern about my test results is that I'm not on a built motor yet, and I won't be able to make the power or revs that @Element Tuning is making yet. I'd like the results to be a more comprehensive, especially since I plan on reaching those power levels and revs before too long but I'm worried about them becoming secret sauce. It'd be quicker and cheaper if somebody in the professional FRS racing business had a spare old motor and a Hydra sitting around at the shop. ...Not to mention the massive thanks from the community.

Well there you go... I suppose I've crossed the Rubicon now. Sideways and smiling.