If I had a spare front cover I would take off the sheet metal separator cover and diagram it. This is from memory.

The two oil ports at the OMP allow oil to circulate within the OMP feed area before it finally drains into pan. If you look at your Sohn adapter, only one port is used (upper) because draining into the pan is not needed. The other port is blocked off. Again not under pressure, just gravity. Someone very helpfully connected a gauge and ran the engine up to redline and it showed 0 psi across all rpm. Its on YT and linked here in one of the discussion threads about the OMP.

Don't take this as gospel, but IIRK, the bottom hole was the stock feed, and it would flow into the pump, and then overfill to the top hole, which went back to sump. It was quite a few years ago when mine was apart, so that memory could be foggy. I do remember I couldn't see what was going on until I took apart the separator inside the cover. Even the Mazda manual oil diagram is not clear, as I remember.

 

Thanks. I have a spare front cover so I'll take a look inside over the weekend.

I'm reading this thread now. Starts to get interesting at post 116:
https://www.rx8club.com/series-i-tec...5/#post2039749

Have also read this one but trying to sift through all the arguments to discern the facts is tiresome...
https://www.rx8club.com/series-i-tec...cation-268559/

If anyone has any good threads to refer to, pls share.


I'm also reviewing the OMP thread on rx7club https://www.rx7club.com/3rd-generati...sified-892750/

 

This will inevitably come up, so might as well deal with it before flames start moving in.

The OMP even stock, is capable of about 30:1 oil/gas ratio at full throttle high rpm.

Most reputable builders say to premix 1-2 oz/gallon and that is enough-which is a lot less.

Nobody has proof one or another which is best, but lots of race engines last long enough on that mixture alone.

I am in the OMP+ premix camp. That pump is designed to give a lot more than most would ever premix. And it is very overdesigned/oversized if Mazda felt 128:1 was enough oil at full throttle. Oil in the chamber is a coolant also...

People fault the OMP because of the low throttle settings, and the housing and seal wear that occurs in daily driver use in my opinion.

It can actually pump a lot of oil, and modified, even more.

It's an "Up to you" kind of thing in my view. I probably use more oil than anyone ever has here in the history of the world, and have yet to see any compression loss in two different engines, both with 70-80k miles now. Not enough to be definitive, but encouraging enough I think. No fouled plugs, rotors show clean except in recess, etc.

I would not run this much 4 stroke oil though, so I am in the Sohn camp as well.

But, guys have gotten a long enough service life without doing any of things I am doing, so there's that.

You have to make up your own mind. I doubt you will find any info that is not contradicted with something else.

It depends on your definition of acceptable service life, and whether you think doing something different will get you where you want to be or not.

 

From the thread on rx7club: https://www.rx7club.com/3rd-generati...0/#post9870699

Not pressurized.

Now off to try and find similar research on the 8's OMP

 

I totally agree with your perspective! Thanks @kevink0000 !
I do plan on running the OMP and will probably premix a little. The Sohn adapter is new to me so I'm still learning about it - and probably over analyzing things as I am prone to do. The research and learning is interesting and enjoyable and gives my mind a break from more serious topics. Ultimately, the results will probably be inconclusive.

 

One thing to remember, for everyone here. You can't use too much oil. There will be no damage to anything (cat excluded) by using a very very very rich oil mix.

Weather it is worth it or not is the question.

Guys on here are nervous going from 1/2 oz to 1 oz premix. Take it easy, fellas. You can run 20:1 2T premix plus OMP on the street and never foul a plug or "carbon up" your engine. Racing even more so.

 

For what it's worth, I have the OMP increased output tune, always premix 1/2oz/gal for normal driving, and will dump in a shitload for track/autox which is roughly 1oz/gal or more. I have the IGN1A coils, with 10/11 plugs, and they seemingly never get dirty or fouled. If you car is dedicated for track you should have a big premix budget LOL, I go through a lot.

 

some people never learn …. Sohn = worthless waste of money.
.

 

Here you go. This is the video I was talking about:

 

@kevink0000 You are frickin awesome! Had found a different video from that guy yesterday but had not seen that one yet!


I was about to install the OMP today but realized that I don’t have a replacement gasket for the Sohn adapter. They never responded to my email asking how to purchase a replacement gasket. I’ll probably just use some black rtv. If anyone has any advice on gasket vs rtv, please share.

 

I used HondaBond, I almost cut one from gasket stock, but the HB worked fine.

 

Made some good progress over the weekend continuing to assemble the engine peripherals / stuff.

• Installed the OMP lines with new crush washers.
• Installed the OMP and the Sohn adapter. I'm not fully sold on this thing but it's here so I'm installing it. This did make routing the OMP lines a bit tight which was annoying. Will have to keep an eye on those to make sure they don't crack over time from vibrations against the alternator bracket.
• Installed the water pump (Remedy), the Mishimoto thermostat and tstat housing.
• Installed the cleaned, rebuilt fuel injectors into the LIM and fuel rail.
• Attached a new main fuel line. Not sure why I ordered it as the old one looked fine but the new one is different - doesn't have that whitish plastic insert into the QD.
• Carefully installed the LIM then the UIM and oil filler stuff.
• Clipped together all the electrical connectors I could find
• Attached the alternator and belt.
• Attached the rear oil cooler line.

Since there is no emissions (because race car), there are a few things that are not present on this engine compared to the ebay engine and FSM. I lost track of the pics of the original engine removal and disassembly pics somehow when I got a new phone. So I did a lot of comparing of pics and eyeballing the 2 sets of parts to make sure it is going together correctly.

I have to buy some 1/8" vacuum caps to replace some hardened ones that have been on the intake manifold too long.

I have to figure out where the 2 large vac lines attach.

Also need to get 2 bungs welded into the header so I can install the EGT sensors.

Getting close!

 

And.... now that I look at the engine all neatly assembled, I just remembered that I had removed the UIM to reach the rear engine hook to remove the engine... Which means I probably need to do the same thing to install the engine... Sigh... Getting old sucks...

Can someone confirm my mistake please?

I also need to figure out if I'm missing any parts to attach the transmission.

 

Yep, UIM needs to be off for engine removal/replacement.

The two hoses in your first pic go to the intake "elbow" thing

 

Thanks for being the confirmation
Team also mentioned that separately.
On the bright side, I guess I have added practice now. hooray for optimism i guess...


Dropped off the header to have the EGT bungs welded in.

 

FWIW I had the UIM in place and R+R with no issue. Harbor Freight hoist also.($99.00)

 

Thanks. I'll just remove it. Not too hard on this car thankfully.
I'm installing this with the transmission attached and a load leveler. Hopefully, it won't be too bad. Getting excited to get the engine back in and be able to drive this thing!

 

you likely won’t get a load leveler to work as it will hit the firewall

or at least I couldn’t …

the front engine pickup point is almost worthless too, bends too easily.
.

 

yeah it did touch the firewall on removal but not enough to be problematic. The front hook did indeed bend but I have a spare. Also, an engine hook from a Miata can work in a pinch in case anyone is ever desperate like I was when removing the engine.


I picked up the header from my fabricator with the EGT bungs welded in. Temporarily attached the header to figure out how to orient them. These 1/4” egt sensors are quite chubby. Hopefully they are as durable as the manufacturer claims. Almost $100 each.

 

In case anyone is curious - and so that I can find this information in the future, these are the sensors that EGT recommended I run for my track / racing use case
https://www.exhaustgas.com/ProductDe...D=56&BasketID=

 

No pics today but my order for 6 new OEM exhaust nuts and the long-*** bolt for the LIM arrived from Mazda Motorsports. Didn't have much time over the weekend but did manage to spend a bit of time getting the engine ready to install:
- Mated the transmission to the engine. That was a pita even outside the car... Getting too old for this...
- Attached the header with the shiny new nuts
- Positioned the EGT sensors and tightened them down
- Removed the UIM

The engine and trans is sitting there poised on my engine hoist waiting for me to have enough time to attempt the install. Hopefully, this coming weekend. Wish me luck.


Still need to empty the 8 year old gas out of the tank. That should be fun.

 

What are you planning to do with the old gas? I have a tank full of 7 year old gas and I have no idea what to do with it. Thought about adding a conditioner to the tank and to try and use it.

 

I can recycle it at one of the race tracks. Thunderhill has gas, oil, coolant and brake fluid recycling. Sonoma and Laguna might too.

I might also google for a local place to recycle so I don’t have this sitting around for an unknown number of months until I get back to the track.

 

the OE exhaust stud threads are M10x1.5,

I hate the OEM exhaust nuts and use an aftermarket nut with a 17mm hex (OEM is 14mm) to help torque them on/off easier along with Nickel anti-seize too and never broke another stud or had another nut issue ever since.
.

 

You hate them because you broke studs when using them? What sort of issues have people had?

What torque values do you / others use when anti-seize is used? The OEM torque specs assume dry threads.