Grizzly

What Oil System mods would i need to run on a High Hp 13b?

I Already have a 85psi Regulator and have done the Thermo wax mod but i have read there is another mod on the E-shaft that removes the Check ball and spring.

What does this Mod do? And is there any thing else i need to do?

Thanks........Chris

copandengr

The E-shaft mod consists of removing the check ball and spring and replacing them with a 2mm Weber carburetor jet. This removes the restriction and allows cooling oil to flow through the rotors all the time. With the stock set up oil does not flow if the oil pressure is 35PSI or below.

The idea behind this is to allow more oil flow through the rotors at higher engine speeds. The hope is better cooling for the rotors. The practical result of this mod is near zero oil pressure at low engine speeds. I performed this mod and my NA has around 8 PSI oil pressure at idle.

If I was doing my engine over again I would NOT do this mod. Going back to the stock set up will require a complete engine tear down. Maybe one day, but it is too much trouble to do now. I just keep the idle speed up at stop lights, etc.

niner

the mod your talking about replaces the ball and spring with a little jet. i dont know what kind to get, call up one of the RX-7 performance shops and they should be able to help.

you could also get ss oil cooler lines

some oil mods are overkill for non race cars, I'd be careful about what all you do

edit: i guess we posted that at the same time. i had similar problems, but when i did my old engine i put a higher pressure regulator in. if i did it over again, i would have re-used the stock one. i forget if it was 85 or 95psi, but thats the type of thing i was trying to warn you about

Grizzly

I will have my Idle set to about 1000-1200 rpm as i'll be running a PB engine.

I have to admit i'm a little confused now! My last engine had a Oil feed problem that killed the bearings, with this new engine i want a realy good oil system (i'll be running big hp).

So what do you guys recomend? if low oil presure on Idle is the cost of a oil system that will handle 500+ hp then i'll live with it, but i dont want to kill my Turbo by running low oil presure.

I could realy do with some Info on this as i'm ready to bolt it all together.

Chris

copandengr

My personal advice would be to keep the stock oil jet system unless you are racing or using the engine in an airplane. I would not recommend this for the street.

The higher pressure regulator will not help here. The problem with the oil jet mod is that you remove a restriction and the oil pump has insufficient capacity to pump this extra oil at low speeds, hence the low oil pressure.

If you are still in doubt, contact some of the race engine builders for their advice.

Grizzly

Ok i've done a bit of reading and have decided not to do the Check ball and spring mod.

I will be doing the Thermo Pellet mod, 85 psi regulator, Stationry gear Window bearings and Aeroquip hoses.

Does that sound more realistic?

Chris

copandengr

Sounds better, Chris. As I said, I will recommend against the e-shaft oil jet mod. There is no real reason to do this on a street car. I built this engine with an idea of using it in an airplane one day, hence the mod. Knowing what I do now I would wait untill actually using it fo my RV-6 to mod the shaft.

scathcart

If you have the wads of cash laying around, the best oiling mod is a dry sump system.

Grizzly

Yeh? I have'nt heard about them on hear is it very expencive?

Is there a kit you can buy? and what is gained by doing it?

Chris

scathcart

About $3000 to set up a good system. (hence the wads of cash laying around). Hardcore racer's only.

http://www.moroso.com/articles/artic...utOilPans.html
(at the bottom)

You can typically hold 12-18 quarts of oil, sit the engine lower by using a smaller pan, and make a couple extra horsepower.

http://www.pineappleracing.com/PricelistSvcs.html
Rob'll do it for $3000, with your rebuild.

Grizzly

Would the Dry sump aid the oil Breather system?

scathcart

What do you mean by oil breather system? The vapour lines that run off the oil filler hose?
You could plumb that into your resevoir.

Grizzly

I have been trying to find a Rx with a Dry sump fitted and there does'nt seem to be any? is this due to cost?

scathcart

Yep. Doesn;t make sense to spend $3000 on a new oil pump when you can buy an entire second gen for that, unless you are racing.

RETed

http://fc3s-pro.com/TECH/MODS/ENGINE...AFT/oiljet.htm



-Ted

Grizzly

Ted, Have you done this mod? Did you find the Oil presure droped at Idle?

RETed

No, not on my car.&nbsp I don't find this mod required unless you're pushing over 400hp...


-Ted