street car gone road race

Impressive build!! Good luck hope you can get back out on the track!

 

Hey thanks man!

 

money isn't worth anything til you spend it

 

LOL

 

So...it has come to my attention...and im SO glad i asked a few guys...but my idle RPM is set too low LOL.

when i asked the original owner of this motor about idle oil pressure the first thing he said was "whats your idle rpm set to" "set it to 1k" he said to me. I obviously dismissed this and kept on feeling like my motor was dead. Well...after talking to a couple other built motor boys it seems this is the norm. 1000-1050rpm, confirmed by a couple of members here.

My current idle is 800rpm i believe, so upping it to 1000-1050rpm should give me at least 5-10psi more idle oil pressure. this would put me way into the "safe" range. ive also collected oil pressures from those who had gauges, and im not totally far off from other built motors at idle, considering my idle is much lower.

I still need to drop by the shop and test this but i think thats it. Just need to get over there and see. Im also going to do the test from the manual, 3k RPM hold at 212f oil temp, pressure should fall between 43psi and 80psi. If i pass there...i think im OK.

 

Better to panic and overthink it

 

yea, if there IS an issue id rather take care of it without ruining the motor.

right now its looking like im good maybe. just a cross between paranoia and not knowing lol.

 

you just described my whole life.

 

LOL

 

Well more info.

went by the shop tonight after work.
Go oil temp to 100c(212f) as mentioned in the manual. Hold rpm at 3k. Pressure was 44-50psi. Manual states 43-80psi as “in spec”.


So...what the fuck. Pull the motor and bring it to machine shop? Or keep on sending it?

idle rpm is confirmed 850rpm. Pressure is 8-12psi. 5w40 oil weight. It’s not looking good.
If I rev the motor out it makes plenty of pressures. It also sounds pretty healthy. No ugly sounds at 850rpm and none at 6700rpm.

so here I am again. Pull the motor and send it to the machine shop or carry on with it?

if we follow the 10psi/1000rpm old school rule this motor is plenty healthy. Right in line with that rule and actually much above it. If I go based on the Mazda manual this motor is barely hanging onto life.

So which is it?

 

based on what you said above, i wouldn't say the motor is just hanging on. it's within spec. it's quite a range, but it's there. who's to say that even if you pull the motor and send it in that it won't have an issue later? i guess what i mean by that is why not just worry about it when you gotta worry about it? if it's seems strong and feels good to you then, hell, let'r rip tater chip!

that being said, i am not a racer and am usually a nervous nelly about everything (you've seen my posts). but stressing over it when it doesn't appear to be a problem based on numbers...don't let that cortisol run your life. just my .01.

 

You could drop the oil pan and check that the balance shaft delete and oil squirters aren't leaking and check the screen on the oil pump as well

If it's not one of those your likely either fine or the motor is done in either case just say fuck it and send it

 

Hey guys thanks for the input. i understand what youre saying and it makes sense.

heres a video of my findings lastnight. you guys tell me what you think. To my ears...it sounds healthy AF. but i dont really know...i think my plan is to put it together on saturday enough that i can do a few laps around the shop. get some real heat into it and see what it does. if it maintains 8-10psi and never drops then honestly...maybe i do just send it?

video of my 3k test and idling sounds at temp

 

Honestly at idle and low load you don't really need much oil pressure

 

I’ve read that. It makes sense. My major concern is it maintaining that oil pressure when the oil is HOT. That’s where the issues will come, if any. I’ll know this weekend. It’ll either leave me on the side of the road, or be perfectly fine in low oil pressure land

 

Just a thought, could it your oil pressure sensor for the gauge that is starting to read low pressure?

Innovate sensors dont exactly have as long of a life as OEM sensors.

 

I mean it’s definitely possible? I’ve only had it installed in the car for one year though. Just last season. I could try a cheap mechanical gauge though I guess

 

ordered myself a REAL basic mechanical gauge to do some testing with. it should be here tomorrow. Lets see if my sending unit may be bad. would be nice right lol

 

Went for a drive today. No issues. Car drove great. Still lower then ideal oil pressure but I keep hearing “loose mains loose rods” “maybe it’ll tighten up when you super heat it on track probably pick up a couple psi’s”. I mean I guess that’s possible.

I’ve basically decided to keep going forward. I’ll keep an eye on oil pressure and if it gets stupid low(like actually 0) then I’ll pull the motor and send it out.

also compression numbers after my test drive. I was worried about this also, but...
As you can see





I’m liking these numbers a shitload more then Im liking my oil pressure numbers lol.

 

PD tune has been ordered/paid for. Can’t wait for the base map so I can go and start doing pulls getting some real shakedown started. Woohoo!