Oil Pressure Report for RA

#1

Was at RA this weekend with Chin. SpecE30 types Al K and Billy Gropp were there too. Chi was there with more of his wife’s terrific cookies.

I still don’t have the oil pressure correctly calibrated on my Traqmate, but it gets a little better each time. The early truth tho is that I’m losing about 15psi on left turns. At RA turn 4 OP plummeted at the beginning of the turn, and then req’d 4 secs to work it’s way back up

Unrelated. I’ve been kinda embarrassed how slow I am at RA. Up until this weekend I was 6secs back from the leaders at RA, and if I was that slow at RR or CMP, I’d go back to doing DE’s. But I’m pleased to report that whereas 150.x had been fairly rare for me at RA, this weekend I was doing 1:48’s and 1:49’s all day long. My best was 1:48.0.

All on old crappy Ebay tires.

Vy nice.

#2

Ranger wrote:

Losing 15 psi doesn’t sound bad unless you are starting at 30 psi. :wink: Is the 4 sec catch-up a function of having to re-pressurize the Accusump?

[quote] My best was 1:48.0.

All on old crappy Ebay tires.

Vy nice.[/quote]

Vy nice indeed.:woohoo: Which corners were you gaining speed in? It drove me nuts when we went to Mid-Ohio a couple years ago for Nationals and the fast guys were all looking for the oldest, most heat-cycled RA1s they could find. They said the tires were faster because they didn’t bind them up in the corners. Were you faster because the crappy tires didn’t scrub speed?

Steve D.

#3

Faster: cooler air=more straightaway talent.Cooler track=cornering talent.

BAM

How were the reports from others?Does Chi like an e36?

RP

#4

That 15psi # is rough because of calibration issues so don’t focus on the exact #. There is certainly a pressure drop, it is mostly on left turns and it amounted to roughly 1/3 of the calibration “range” that I had the Traqmate programmed to. That much is certain. But that 15psi # is rough.

5mph faster in 3. 2mph faster coming out of 7 which oddly enough only lasted for abotu 1/3rd of the back straight. 1.5mph faster thru 10 and 2mph faster thru 12.

I sure thought that I was faster in 1, but the data shows otherwise.

I experimented with bounding over the L side gator approaching turn 3, and the right side gator when approaching turn 5, and those ideas occasionally worked well.

Re. Chi. The E36 is apparently running well, but he is recalling his E30 with some fondness. There might be hope that in a couple yrs he may be back in an E30.

#5

Ranger wrote:

Aero drag.

#6

Patton wrote:

[quote]Does Chi like an e36?
[/quote]

In a word, no. I do miss Mr. Junky.

Although Mr. Trashy has more power, it’s heavier and not as direct in handling feedback. A pig.

Finally managed to dial out the terrible understeer on Sunday morning and barely managed to run as fast as Mr. Junky.

Still can’t toss the car around yet.

E30 > E36.

#7

csrow wrote:

(Miata == E30) > E36?

Or

Miata > E30 > E36?

Etc. Judging from Steve D’s collection of non-running “parts” cars (or shared pack rack obsession), I’d have to say it seems like he likes the SM equal to the SE30.

#8

TheRedBaron wrote:

[quote](Miata == E30) > E36?

Or

Miata > E30 > E36?
[/quote]

mmm… if I had to choose one, it would be (miata~~E30) > E36.

Miata are lighter and can corner better but I like the mid torque of M20.

They both are fun track cars but in a different way. I love the way you can toss E30 around to point the car. I love the rail stickiness of miata in mid corner and the quick turn-in.

Both are more fun than E36.

#9

This thread is jacked.

Anyway - I think the Miata vs. E30 debate could go on forever. I have only driven one Spec Miata and it was a students car in a school situation. The point is, I couldn’t wring it’s little Nippo neck so I have no idea what an SM is really like.

I have observed that different cars like different tracks. The SM cars are faster at Roebling, and surprisingly Sebring (this must be an aero drag thing) but it appears that the BMWs are faster at Mid-Ohio.

Personally, I like the bigger cockpit and the 6 cylinder torque and sound of the BMW. I also believe that it is easier to be competitive (I am talking mid pack here) with a junkyard Bimmer than junkyard Miata.

My $0.02

Don

#10

donstevens wrote:

[quote]but it appears that the BMWs are faster at Mid-Ohio.
[/quote]

Top National SM Drivers are faster than us at Mid Ohio. In July the top 2 SM were faster than me, but I was faster than the rest. So pretty even.

#11

TheRedBaron wrote:

Huh? I have a 1989 E30 stripped and ready for cage, a 1984 E30 roller, a 1991 E30 daily driver and a 1989 E30 race car.

I also have a 1999 Spec Miata.

That being said, I like whichever car I just got out of better. Right now, that means Miata. After Nationals, hopefully it will mean E30.

Here’s my rating:
Challenging to drive fast - E30
Easy to drive fast - Miata
On the ragged edge at every corner to podium - Tie
Impressive to people who don’t race - E30
Impressive to hairdressers - Miata
Impressive to closeted hairdressers cough IndyJim cough - E30
Cost to build/maintain - Miata
Cost to keep up with “development” - E30
Cost to run a weekend - Tie
Resale value - Miata
Field size/quality - depends on the region/race
Exploitable rule set - E30
Interior room/escape hatch - E30
Engine sound - E30
Like a big go kart - Miata
Fun going 2 wide - Tie
Welcoming to new guys - E30 (by a narrow margin)

#12

Damn, we’ll have to work harder on “welcoming to new guys” and “quality of the field” here in the Southeast.

The answer: send DeVinney to MA.(Insert that infamous smiley face dude.:slight_smile:

I’ll take it as a challenge. Show up at RRR this weekend and you can race for any position after the top two. The Patton’s will even pay for your Friday dinner (buying friends again,insert smiley face dude.:slight_smile:

RP

ps. I swear I didn’t find that goober…does it just show up when you type :slight_smile: or is it : )

#13

Steve - which one is easier to heel / toe shift and drive into a wall?

Craig shortly will only be able to log on during the baby’s nap time, so you may have to wait awhile for his smart a$$ response, if he isn’t too tired to think of one.

#14

Patton wrote:

[quote]Damn, we’ll have to work harder on “welcoming to new guys” and “quality of the field” here in the Southeast.

The answer: send DeVinney to MA.(Insert that infamous smiley face dude.:slight_smile:

I’ll take it as a challenge. Show up at RRR this weekend and you can race for any position after the top two. The Patton’s will even pay for your Friday dinner (buying friends again,insert smiley face dude.:slight_smile:
[/quote]

I think both groups are damn good at welcoming to new guys. Probably too welcoming since you let me in! :laugh:

I would love to race this weekend, but I’ve got a lot of money committed to Utah and I would hate to screw it all up and hurt the car this weekend. Not to mention that it has no motor as of right now - maybe dyno tomorrow to see if we solved the high RPM miss… So y’all go ahead and fill up the podium with Pattons and a Taylor!

I’ve got 2 good back up plans for Utah if the damn thing isn’t running right.

Steve D.

#15

Utah back-up plan: Attend the MA VIR race in October and the caliber of competition will be like being at the Nationals.

RP

Thread hijack, oil pressure discussions are boring.
Where’s Geiger?

#16

I thought our “welcome new guy” plan of having Jones wreck into them was going well?

#17

Patton wrote:

[quote]Utah back-up plan: Attend the MA VIR race in October and the caliber of competition will be like being at the Nationals.
[/quote]

Unfortunately, I can’t make that happen. I signed up for the 13 hour at VIR on Halloween in Ryan’s Integra. To avoid feeling like the horrible father I am for missing the sugarfest, I plan to spend time with the kids the rest of October.

Geiger’s probably still in the phase where he thinks he can be a good dad and a racer. What a chump. :laugh: :stuck_out_tongue:

THREAD REDIRECT------------------------
Ranger -

Can you tell from your data if you lost pressure and went from “good” to “adequate” or from “adequate” to “worrisome”? Does your calibration range go down to zero?

Steve D.

#18

Patton wrote:

Road Altanta in Dec is a go for me. Magagnoli and Osborne are interested. Get the MA folks interested and you won’t even have to go anywhere.

#19

Steve D wrote:

[quote]Ranger -

Can you tell from your data if you lost pressure and went from “good” to “adequate” or from “adequate” to “worrisome”? Does your calibration range go down to z

#20

Steve D wrote:

[quote]Ranger -

Can you tell from your data if you lost pressure and went from “good” to “adequate” or from “adequate” to “worrisome”? Does your calibration range go down to z[/quote]

Odd. My answer from this afternoon got all goofed up.

Here’s what I can tell you…

  1. I have OP warning light switches at galley and pump. They are separated by the Accusump’s checkvalve, although a couple times I’ve shut the valve to the sump just to see if that changes any data. Those switches are set at 15psi and have not illuminated. So the OP drops have not gone below 15psi.

  2. Because of the calibration issues, I’ve no more info then what I’ve already provided.

  3. Worrisome, adequate and good. Frankly, I’ve not figured out yet what is worrisome adequate and good. Should I be worried at 30psi at red line? I don’t know. There’s lots of opinions, but getting hard data is, well, hard.

  4. There is another problem here. We are focused on OP, but the important issue is oil flow rate. The pump needs to provide sufficient flow such that it can provide more oil then what leaks out of the sides of the bearings. But we aren’t measuring flow rate, we’re measuring pressure and attempting to infer flow rate.

When bearings are getting worn the restriction to oil flow is low because the oil can easily flow out the large gaps beteen the worn bearings. Low viscosity oil more easily flows out thru bearing gaps so the pump can’t maintain as high a pressure.

In the oil viscosity dicussions we talk about oil pressure. But low oil pressure is a product of oil visc and bearing gap. LOW OP DOES NOT CAUSE BEARING WEAR. Consider what that means…We are measuring oil pressure and talking as if the low OP is causing a problem. But it’s not the cause of a problem…it’s low oil flow rate that is the cause of worn bearings (assuming that the bearing problem is cumulative wear) Low OP is a result, a symptom, of the problem. So we are measuring a symptom (or a result) and trying to infer information about it’s cause. It’s like looking at a wrecked car (result) and trying to figure out details re. the cause, if the owner ran off the road at night because she was putting on make-up.

I just dumped a load of 10W40 and put in 20W50. I was uncomfortable that the OP are redline was 35psi. But I really don’t know what I’m doing. If the pump was maintaining 35psi, it’s reasonable to suppose that it was staying ahead of the oil leaking out of the bearings.

Maybe what this OP pressure stuff is telling us is that our oil pump is inadequate to what we are asking of it. I just don’t know.

Here’s a great article:
http://www.zddplus.com/TechBrief11%20-%20Internal%20Combustion%20Engine%20Lubrication.pdf

And finally, a guy in the UK sent me a BMW technical doc the other day that said 10W40 is also an approved oil visc for the M20B25 during high temperature operation.