I'm planning a street-driven (Daily) Aux-Bridged N/A.

My question is, should I replace the Oil Jets check ball and spring assembly with a weber carburator jet? I don't intend to be on my car all the time, I just want the ability to, if desired. This car will see <3000 RPM on an hourly basis.

I've heard that this modification should only be done on engines that intend to be driven at high-rpm; so I felt I should ask. ~Colby

 

that mod is suggested in the racing beat catalgue. i plan on doing this also before i finish.... i don't think it will cause a prob... if anything you might burn a hair more oil. but its better to have the protection than not \\ thats the way i see it......

 

See my post in the FC section as why I'm concerned.

Notice where it is the the RB catalog... it mentions it for race applications. That's why I ask... along w/ the other reason in the FC forum.

 

The e-shaft oil jets have no effect on oil consumption. The oil that flows through the jets enters the inside of the rotors for cooling purposes then returns to the pan through the center plate housing...

 

I have the jets in my T-II engine. I have the larger of the 2 options. I find that at stock idle rpm there just isn't enough oil pressure. I keep the engine idle at 1000 rpm and this problem is gone. With the big streetport that I have it is just a smoother rpm to idle at anyways.

 

Don't know if these jets are what you are talking about, but here is what Mazdaspeed has to say:

http://www.mazdamotorsports.com/weba...ject=eccentric

 

IMO, they say that because fixed jets always cool the rotors. This could seriously effect cold start emissions similar to the thermopellet in the end of the shaft.

 

I'm thinking maybe I should put in a smaller than 2mm jet, to up the oil pressure a tad... as I think that's the reason why it's not intended for street use.

 

2mm? I've got .220" jets installed & my oil pressure is fine. If anything my oil pressure is high. So far I've been using Havoline 20W50.

I'm sure your "2mm" is a typo because that's only .078". With that kind of restriction I would expect your rotors to overheat & cause detonation under boost.

Perhaps your low oil pressure is due to something else? Bad sending unit? What year is your car?

 

I don't have bad oil pressure. I'm tearing my engine down while rebuilding it.

Racing Beat reccomends (under a sub-heading for high-rpm racing engines) to remove the check valce from the E-shaft, and fit a 2MM carb jet into the back.

There is no boost, this is N/A... also, I doubt you have quarter-inch jets in your e-shaft; more likely the 2.2MM that Racing Beat reccomends for FI applications.

 

I've got the 2.2's in mine. If you are just staying n/a then the 2's are fine.

 

I am using Weber .200 jets in my e-shaft. Oil pressure and everything else is fine. I bought them from Mazdatrix, here's a link to the page. http://www.mazdatrix.com/r-11.htm

 

I have done this with my engine. I have noticed low oil pressure at Idle like 10psi
but by 3k rmp i have 60psi, I run 20w/50 oil. I don't know if this is a problem?
Since idleing can't be very hard on an engine I'll say its probably ok as long as oil pressure is up near 60psi @ 3k rpm. I'll upgrade pump and regulators next time.

 

Concerning FDs only:

When I rebuilt my engine, I installed the racing oil jets that MazdaSpeed recommends. I also used my Dremel tool to clean out/reshape the oil pump inlet and outlets in the front side housing.

At idle my oil pressure is over 40 PSI.

 

I have the smaller Mazdaspeed oil jets in my daily driven TII with full oil mods including the sloppiest FD rotor bearings further race clearanced.

I actually did it TO DROP oil pressure at idle as even with a restrictor it was overwhelming the turbo oil seals.

The normal reason for doing this mod is MORE oil to the rotor bearings at high rpm where the stock oil jets flow more than the race jets and so limit oil to the bearings.

It shows 20-30psi at idle depending on on how gassy the 10-40 oil is. You don't need any significant oil pressure at idle on a rotary as the bearings are huge and the forces are low.

It is not recommended for street cars because it will take longer to warm up (emmisions).

 

+1. Those have been my results as well. At idle, there's no need for gobs of oil pressure anyways. Rule of thumb -- 10psi of pressure per 1000rpm of engine operation. Been doing the oil jet mod on mine for a really long time; not quite 10 years I think. I'm running the Weber carb 220's in mine. In the summer time, when it's crankin' hot out here in Texas, the oil pressure at idle (1200-1300rpm) sits around 15psi.

http://bdc.cyberosity.com/v/Technical/E-Shaft-Oil-Jets/

B

 

Same here. I have 10-15 psi at idle and see 55 at about 3Gs. 65+ at 6G

 

Hmm I thought the jet-mod. was to limit the amount of oil in the rotors during high rpms (as in full blown race motors)

 

Yes, it lowers the amount of oil going into the rotors at high rpm by having a smaller orfice which leads to the intended benifit of more oil going to the rotor bearings so they seize less often, etc.

 

Ha - I knew it