So my 250k mile motor decided to follow suit to my other motor and spun a rod bearing. So my J30 is out of commission for a while. I picked up an 87 BMW 325Ci that is gonna be my new DD and the J30 gets to go under more modification. Been talking to Ash with AshSpecZ some about how this is my second motor I have spun a rod bearing on. He told me some info that should be helpful. First off the best oil viscosity is 15w-50 for these motors. Also he shimmed the oil pressure relief valve with some washers to increase the oil pressure some.

So basically I am getting a 300zx NA motor with 150k on it and when I drop the pan I am going to replace the rod bearings with new ones and go ahead and put a new pump on and shim it. I still have my intake plenum to finish and going to dress up the engine bay some more with the motor out. Simplifying the PCV system as well since it is now completely removed from my plenum. Have a 300zx low pressure AC line and going to install that. Fresh oil seals on the entire motor and clean it up good. Should have it running by December.

Also during this time going to try a new suspension setup with better results than the 240sx suspension.

nice. can't wait to see the end result.

Seems like a good time to get a TT engine Buddy !!

Sorry the J is down.

"We can rebuild him."

Post photos so we can live vicariously through you

That sucks but as a guy that just put in rod bearings I will say shimming and the use of thick oil is going to net over 100psi oil pressure.
I was unhappy with my replacement bearing fit, to race I was hoping for a standard replacement bearing fitment towards the loose side of the specs, no dice, everything went back mid toward the tight side, 10w30 was selected with the same used untouched oil pump.

Pressure +60psi hot @3500rpm 30 psi Idle and + 80psi cold ( outside temp 80 deg)

well finally start to get going on the project. friend is doing a motor swap on his 300zx so he gave me his NA motor and going to do some work to it before i drop it in. just going to save up a lot of pics and post them all up at the same time.

Here is what I'm doing to the J: tearing motor down, cleaning entire block/painting, pulling pan, find out grade for rod bearings, buy rod bearings, replace rod bearings, shim oil pump pressure relief valve, replace all the oil seals, paint exhaust, mod exhaust valve covers to delete pcv system, finish modding intake plenum and get it powdercoated, gonna need new silicone hoses for the 60mm tb, wire tuck coil pack and injector harness, swap motor mounts, swap on j30 exhaust, swap on j30 oil pick up and pan, install new style cas, clean timing belt covers and paint, install all my lightweight pulleys, clean transmission and paint silver, repaint engine bay while motor is out, reroute some electrical stuff, drop motor and trans in and get it running. then comes suspension by replacing my front wheel hubs, front coilover inserts and put in stiffer spring rates. 2 or 3 wheels need to be fixed cause they are bent and need to go back inside the diff and reset it.

also got the AC low pressure line out of my friends 300zx and need to get the J30 end welded on to mount it. pretty much instead of the thick AC line running behind the motor and next to the drivers side exhaust, this will run on the passenger side frame rail and go in front of the motor along the sway bar. looking for better clearance around the motor.

made this small enclosure for the motors. i still need to get my J30 towed home and pull its motor.

Would love to work on a VG30de "Out" of the car.

Are you parting out your other J or have you gotten rid of it already? I couldnt find a way to PM you.

lol i am not getting rid of it cause of a blown motor



here is the 300zx motor torn down a good bit and getting ready to clean it up. doing a compression check and finding out what grade of rod bearings to use before removing timing belt, crank pulley and cam gears.

Make sure to get the 300zx water pump and pulley out of your parts mix, they are different!

swimshark wrote:lol i am not getting rid of it cause of a blown motor

Yeah I was referring to you having 2 J30s or not.

here is an update on whats going down with my J30. taking my sweet time on it haha


interior is completely stripped and motor is still being worked on











done



solid shifter plate and new intake filters


velocity stacks


pretty much having to design baffles in the J30 oil pan since it does not have any. suspension will be sorted out soon and then longest part of the build will be the intake. more to come on what i am doing with it.

Cant wait !! I will be starting the polish job on the plenum i bought from ya in the next few weeks.

Sorry I dropped off the planet, big computer issues (still not entirely resolved)

Is there a past problem with your pressure or just worried about past rod issues? I admit the oil pressure can drop on a high G right hander but it only happens when there is 3 quarts or less in the pan, as a precaution the oil is run .5 to .75 qt overfill, we just ran road atlanta 14 hours never raising the hood.
When we first started racing the PCV system was sucking huge amounts of oil so a large gauge, 3 addl oil lights and a buzzer set @ 20 psi now lives below the clock but since the pcv reroute/partial delete oil consumption has stopped, never has the buzzer sounded on track. 12,000 race miles and counting, 5000 miles on rod bearing set 2.

Just curious

i havent had issues with oil consumption but spun rod bearing on second motor. noticed that the J30 pan is not baffled like the 300zx pan. also you can increase the pressure relief valve to increase oil pressure after 3000rpm. have a friend and Z guru who told me to try that along with thicker oil. the bearings will last longer.

Great pics! I really need to go back and pay more attn to where your HP is coming from, those track bimmers are sure getting annoying

Never had a shortage of pressure while revving, the rod bearing that almost failed was cyl #1 , the rest looked good enough to continue the fight but not good enough to ignore with the pan off, otherwise there was no signs of actual starvation despite 100,000 street miles + 5000 wide open track miles, I plastigagued rod bearings going back together, was alarmed things were too tight and put lighter oil in, now tracking with 10w30 castrol + lucas to keep hot-in-gear idle pressure just over the 20psi (dash lights up and buzzes if under)

If time permits a blown up mock engine from a 300z, oil pan and all, will be put in the J to asses the possibility of pushing the driveline back 10 inches for better weight distribution, otherwise, either way, I still intend to run thin oil with no pressure spring mods as I feel it will only contribute to wasted hp and increased oil temps.
I suspect you lost those engines to simple wear, in my case checking/replacing rod bearings prevented issues.

yah i didnt have the option to check bearings since it was my DD. did 45000 miles in 2010. mine was cylinder 3. bearing was completely gone. no prior warnings, just went one night coming home from work. im replacing the bearings with oem 300zx bearings on all 6 cylinders. you want to run a w40 or w50 oil. the w30 will get too thin and not lube properly. been proved by a friend who specializes in the 300zxTT market. he swapped his bearings out every 15k for testing and finally found that thicker oil and higher pressure solves the wearing issue.

pic updates once again. got interior mostly done, just finishing up wiring. next on agenda is putting motor back together and then suspension.

Where did you get them sweet looking velocity stacks; how much were they (I only need one of course), and do you know if the manufacturer/dealer will sell just a stack all by its lonesome?

What did you use to clean the interior and plastics?

here is a link to the velocity stack: http://www.z1motorsports.com/product_in ... ts_id=2566

as for interior pieces i just used carpet cleaner and a cheap wash cloth then re-dyed them all with this stuff: http://www.detailyourcar.com/vinyl-plas ... p-258.html

picked up headgaskets, head bolts and getting 300zx 5spd cams tonight. then time to assemble motor this weekend.

I have been looking at cams lately and found we seem to already run the 300z manual cams (aside from early/late) the only differences seem to be 300z auto turbo and OBD2 the rest seem to be the same, I rough measured cams from a JDM turbo engine, 2-300zx cores, then used the 1995 j30 FSM and the JWT website for research.

300zx cams installed and waiting on a dowel pin for the block/head to install the heads back on to the block.

this is where i am at with the motor

Looking good, love those sprockets!

here is what they are

http://www.z1motorsports.com/product_in ... ts_id=5227

Wish we could use those!

Fired mine up today, somehow I have injector rail vacuum leaks

get these and select the viton option.

http://www.z1motorsports.com/product_in ... ts_id=5220

Thanks for the link but it was more complicated and pretty easy to fix once I figured it out.
http://www.amazon.com/Permatex-82194-Hi ... B000HBGI8K