I got this motor from a friend.
He spun a bearing from low oil in the motor.
Now this is a revup motor which are known for
their oil consumption issue. It's been sitting in
my garage for about a year and sat in his backyard
for a better part a year. Now that is about to get warmer
I'm itching to work on this motor.

I was looking at the Arias Piston website and I see they offer
2 different piston with diff Bore and CR.

I have read that if the motor is a oil consumption motor
to get .020 over bored so you can deck the block or can I get away with using standard bore.

My question now is what should be the proper bore size
to buy the pistons in?

I see they offer these 2 options.

Bore Comp. Dome Compression RatioComp. Gram
3.760 / 95.50 1.174 -15 8.5 352
3.780 / 96.00 1.174 -15 8.6 356

 

I personally like JE pistons the best. i would definitely go 3.780 which is .0020 over factory bore. We have a full in house machine shop with all the latest up to date equipment and can do anything you would like. Give me a call if you have any questions.

http://www.alteredatmosphere.com/cnc/

 

Thanks for the offer Jeremy.
Really looking to do this myself with the help of someone locally.
The reason I ask specifically about the Arias is cause I see someone
selling a set for good price.

Anyone have anything on CP Pistons with a Pauter rod setup?

 

If you spun a bearing it brings up a question of whether or not the block is even salvageable. Have that checked as well as the condition of the cylinder walls before you buy anything. You may not need to bore it out if the cylinder walls are in good condition. This could save you money in machining costs as well.

 

how would spinning a bearing make the block unsalvagable?

 

If it is a spun bearing I would think max is having the crank check and polished.
The walls will def need checked for abrasiveness since he went low on oil but the
motor never locked nothing that doesn't have to be done anyway when building a motor

 

Glen do you know if it was a rod bearing or crank bearing that spun? I would even have the crank checked to see if it falls within Nissan OEM specs. Last thing you want is to build a motor install it and blow because your crank was damaged or not straight. I know you said it was a simple spun bearing, but nothing is ever really simple with these motors. I've been through a few so I might know a thing or 2.

 

I can guarantee you he speaks from experience.

 

If the bearing was spun, i would probably trash the crank. The block can be line honed and fixed unless it was driven around a lot.

Definitely have it all checked out in full detail before you mess around with paying anything to have it machined.

 

Spinning a crank bearing can be bad news if it caused really deep grooves. +1 on the crank possibly being garbage as well. I think AAM can scope the block to check tolerences against factory spec correct?
Spend a few extra bucks and get yourself a full set of specs on your block, it will pay for itself in piece of mind down the road.... trust me on that.

 

I turned the crank by hand while it's on the engine stand and it seems to move pretty freely. Granted nothing is really known until I actually take the block apart. The crank will definitely be inspected. I won't take any chances to
save a buck. My car is still running strong but eventually i want to pull the motor and go for more power before I have 2 damaged motors.

 

i wouldnt advise turning it at all. It could only possibly damage the crank worse. If there are any marks on the crank i would trash it. Not worth putting any money into it and having to do it twice.

 

Glex ... you really need to have someone with the proper equipment check the block and crank for damage and any measurements that are out of spec. You will NEVER be able to eyeball or feel your way through that.

Do it right, do it once.

 

Cranks are not expensive to buy new even if it needs a new one. Any machine shop can magnaflux the crank, put it on a balancer, and tell you if its in good shape or not - not expensive either.

Dropping new pistons into an existing block is a recipe for disaster....they make stock bore pistons for those dropping them into brand new factory fresh blocks. Even then, it pays to have the liners checked for true-ness, as not even the factory is perfect, and certainly was not designed with the stresses of boost and revs in mind. If it's worth spending the time on, it's worth doing it right. Doing it any other way all but guarantees you get to do it again at some point...which is neither cheap, nor fun.

 

I bought a new crank for my motor build 7/17/2007....
list price was $745.83
paid $557.51 from my parts girl.

I would consider this fairly expensive

 

Everything is relative - I am talking big picture. Compared to the cost of buying a new motor, or even buying a used, running short block, it's not expensive

 

I still strongly disagree. I payed less for my rods. I would agree if it were less than 10% of the parts cost of the build. In my case it was nearly 20% of my parts cost..... regardless 550 bucks is 550 bucks

 

oh well, difference of opinion

 

pmed

 

Why couldn't Nissan just put some beefy rods in from the factory and we could all have more fun! Yea Yea I know, they serve their purpose, but damnit Toyota overbuilt the 2jz in the Supra. All you need to do is bolt on bigger turbos and 600hp is no big deal. Too bad 350Z'a aren't FI'ed stock.