aidandj

iTrader: (5)

He has an accusump.

thumpetto007

iTrader: (15)

run amsoil dominator. I agree it is the oil, but the oil quality is not enough, I'd guess you need the polish crank, and do some additional oiling mods, maybe even run slightly looser crank bearing tolerance, and some sort of modified/reinforced crank mains.

just a huge guess

patsmx5

iTrader: (16)

I don't know yet, I gotta research that and see, but looks like Amsoil is good but nobody near me has it, tried to buy some at the local speed shop today but they didn't stock it. I'd really like to run a good oil I can actually buy and not have to order and wait for, if possible. For now I plan to run some "synthetic" oil for street driving/not boosting much and break in the new bearings for a few miles, then change it and put some good oil in.

Thanks. I'm expecting to rebuild this motor soon, probably this winter, and if I do, I'll probably be doing all of that.


Maybe, but I know i can make some things better vs what I'm doing now. I know I'm pushing the car hard for the setup.

I may very well be running this if I can find a local place to pick it up for a fair price and not have to order it.


So a good update. I got the new mazda bearings this morning. They looked MINT, but of course they should since they're new and expensive... Anyways got all the bearings replaced. Having now seen all the old bearings, it's obvious RPM is the main thing killing the bearings. Oh yeah, some of the bearings are HAMMERED a lot worse than the above pics.

What I found was:

Rod bearings, all four show more wear on bottoms shell than the top shell (suggest RPM loading more significant than power loading)
All main bearings show more wear on top shells than bottom shells
Front and rear main bearings show more wear than the inner 3, suggesing crank flex is a big factor.
Top side of mains show a lot more wear than bottom side, again, suggest RPM related loading is a factor.

I'll upload pics later, gotta try to get this thing back together right now.

codrus

Maybe Texas outlawed Ponzi scheme oil.

--Ian

patsmx5

iTrader: (16)

What oil do you run?

Savington

iTrader: (31)

I ship Amsoil Dominator all over the place. 10w30 and 15w50 in stock, I would do 15w50 in your motor.

Savington

iTrader: (31)

Monster clearances and monster film strength to cope with the mega bearing abuse. Upgrading the pump will bring the flow back.

codrus

The kind that Savington hates (Redline).

I don't have any comments on the quality of the oil that Amsoil sells, I just don't like their marketing strategy.

--Ian

sixshooter

iTrader: (12)

Race engines typically have loose bottom ends, as Sav said. They tolerate the stresses of revs better.

I've run Shaeffer recently because of bitog info but would run dominator just as quickly. Good stuff.

aidandj

iTrader: (5)

I think you misunderstand their marketing strategy...

Pat. Buy my HX bearings. Extra clearances for that loose bottom end. Bring all the boys to the yard.
​​​​​

Madjak

I run to 8,800 RPM constantly in my N/A engine. Sure it doesn't have the HP but I think it's revs combined with oil loss / degradation doing the damage not power. I destroyed a big end before I installed a sump baffle and all the other bearings looked pretty much exactly to yours. I think I was getting oil accumulating in the head due to the combination of big revs / cornering or braking G's and then under brakes, whilst the oil level was low, I'd get a couple of oil pressure dips. The problem with this is the pickup sucks air and even if you are running an accusump you'll get air bubbles traveling through the oiling system.

My specs:
Penrite 15w-50 filled to above 'F'
Stock Oil pump - oil relief blocked
External oil relief valve set to 50PSI (pressure runs 50 PSI flat at anything over a few thousand RPM)
External oil cooler (10AN lines)
Stock crank, Crower Rods, Wiseco Pistons, no oil squirters, no VVT (BP-05)
ACL Race standard sized bearings - crank / big end

I change oil & filter every 3-4 events, and check levels every 2 or so runs.

On a side note I buzzed the engine on Saturday hitting 3rd instead of 5th. It was a combination of brain fade and over excitement. Logs say it it 10,800rpm and I actually caught the clutch so it wasn't a full release.... otherwise we'd be talking 11,500 rpm. I completed the 2 day event but I'm tossing up if I should drop the sump and check the bearings. I think I might after reading this thread.

z31maniac

Anyone used this stuff? Has good UOAs for tracking on E85.

Performance Racing Oils - Millers Oils Classic and Performance Products

Leafy

iTrader: (1)

Pat pepboys, advanced, and napa all carry the valvoline VR1. It's still got a higher film strength than the amsoil.

Savington

iTrader: (31)

At what temperature?

Leafy

iTrader: (1)

You have data for amsoil at 230°F? The guy who did all the testing himself by buying his own ball bearing rig sold out to some snake oil oil additive company like 2 years after he tested all the oils that were out back then so his website and bitog post by him got all screwed up with ZOMG running castrol gtx and the magic bean excretion is better than the oil nasa uses. But up till then it was a couple conventional high mileage oils that I didn't consider because they probably had an insufficient additive package and high heat performance, then one specific straight weight non-detergent of joe gibbs oil, then vr1 conventional, then vr1 synthetic, then a smattering of non-detergent racing oils, and then I cant remember if joe gibbs or amsoil were the next highest detergent racing oils. I know amsoil has come out some new products or at least re-named them, the dominator oil didnt exist back when this testing was done.

I found the site that I remember, and its all gunked up with oil additives but it looks like he's tested a bunch more oils since last time and there might be some even better choices. He even has the dominator oil on there, with a lower film strength than the amsoil signature series... https://540ratblog.wordpress.com/201...-test-ranking/

patsmx5

iTrader: (16)

Thanks for the tip, I'm going to check them out. A brief search showed some pretty positive reviews. If you have a link to the bitog info you saw that helped you make your decision, I'd love to see it!

Thank you for your help, I was hoping you would chime in! I agree I think RPM and oil quality were the main things that contributed. I also have 8AN oil lines going from the sandwhich plate to the FM filter relocation, etc. So next time car is apart, those will probably be swapped for 10AN parts for less pressure drop in the lines/fittings. What kind of oil temps do you see with your setup? I assume your regulate your pressure after the cooler?



Interesting, if they keep it in stock that's a big plus, so would increaed film strength. I'll see if the local Advance has it tomorrow, and try to read up about it a bit too. I'll check out your link when I have some time to read, it appears to be a book but I think I've seen that before.

It would be nice if there was an honest list of oils and their specs so people could easily compare without requiring hours and hours of searching and asking if this source that says X is oil is the best also happens to sell X oil.

As an update, the bearings are in, oil pan is back on, subframe just went back in. Lordy that was work getting the subframe back in, what a pain. Gonna try to get the rest of the car back together and fire it up tonight, I hope.

Madjak

It's the one thing I don't log but I have a good idea of where the temps sit. My set up is a little unique so it may or may not help. Whilst idling in the pits, I can only get the oil temp to 65 - 70 (149 - 159F) deg with the aid of a bit of heat soak from the previous run. At the end of the first warm up lap it gets to around 80 - 85 (175 - 185F) depending on how much time I spend warming the tyres vs engine revs and by the end of my first hot lap I'm generally up around the 100 (212F) mark then it will slowly rise to around 110 (230F) and sit there throughout the rest of the session. Really I don't get to see much oil temp rise until the engine is up past 6000 revs, then the heat builds more rapidly.

With my engine the block is grouted so it only sees a small amount of coolant running through it and I don't run oil squirters. This means all the heat load in the block needs to be handled by the oil cooler. I don't think it's massively different to other engines as most the heat in the oil is generated by oil shearing rather than heat from combustion. I also find my oil smells pretty fuelly from running E85 and I tend to get lots of water in my catch can especially at colder events. I definitely find when running E85 I need to change oil a lot more often.

With the oil pressure, it doesn't really matter where you place the regulator, it's more where you measure the pressure to set it. So I have an 10AN line from the oil sandwich plate to the regulator (30cm), a return to the sump and then a line from the regulator to the oil cooler and one back to the sandwich plate. I run a Peterson oil pressure regulator which was around $200 from memory and it is super easy to adjust the pressure by winding out or in the adjustment bolt. It is a much larger diameter bore than the stock regulator and I was told that it helps stop pressure chattering at high revs (which also destroys the oil pump gear). So regardless where the regulator is located if you measure the pressure near the head or block and adjust to a target it works fine. Logs of my oil pressure pretty much sit dead flat throughout a session until the revs drop down towards idle and the relief is fully closed.

patsmx5

iTrader: (16)

It runs!

I spun the motor over to prime the oil system before this video with the coils/injector fuse pulled. Then reinstalled fuses and filmed this.

https://youtu.be/PweO6Vo4FeQ

All I did was this, and a few other startups and idling/light rev to 3K once to see how it's doing. Motor is much more quiet on startup and now gets oil pressure on the key. I got a few other things to do tomorrow, then I'll drive it and see how it does. So far, much improved. I hope the repair holds up!

I'll try to get some pics up tomorrow and explain some of the modifications I made to the oil system.

Thanks for the info. It sounds like your temps are pretty solid.

Couple more questions if you don't mind. How much do you overfill the oil? Why do you run a 50W? Do you have any pics or info on how you did the grout in the block? Why did you do that?

I think you're right about the accusump, I actually removed it now. I think you're right, before I was sucking air and loosing pressure at high revs, and while the accusump should have given it some oil to help out, there was still air being pumped into the system which of course is bad, so I'm gonna try to fix that problem if it exist.

Madjak

I just fill up past the line a few mm... and make sure it is topped up throughout the day. I run 50W because that's what I have always run and what the MX5 race engine builders here recommend it but most are still a bit old school. I have some 10W40 to go in for the next oil change but then part of me says don't change anything because it is currently working.

Grouting the block helps reinforce the cylinders. This engine I purchased with it already done. Basically the grout runs from the bottom of the hole where the water pump inserts sloping upwards to the back of the block where it would be 1 inch from the deck. It's a dull grey epoxy material.

The oil pressure dips under braking can only mean the pickup is sucking air which just can't occur in a high reving engine regardless of accusump or not. If you don't log oil pressures I'd set it up because it's very handy for figuring out these issues. I run a $20 Ebay 100PSI sensor and they are piece of cake to install and log on any aftermarket ecu.

patsmx5

iTrader: (16)

Thanks for the info.

As a small update, I did let it warm up and then rev'd the engine up to about 7K a couple times, and thank god the vibration above 4K is now GONE! I was hoping the bearings were the cause, and they were. Now feels really smooth. Very happy about that.