Armlocker

iTrader: (3)

Im not going to start a typical build thread because the whole project will take some time so I figured id make small threads with each portion of the build as i decide to progress with it. Basically right now I just wanted some opinions on certain details of the bottom end.

I've got wiseco 8.8:1 pistons, eagle H-beam rods, and ACL race bearings. Id like some first hand experience on the steps to take (or not take). Seems like theres so many options with the crank alone. I made a thread regarding knife edging and peoples experiences with it on the VQ crank and came up with nothing. Lighten and balance only? Leave it alone? I want to hear your opinions. Did you built guys have everything magna fluxed for cracks before assembly? Did you have your oil holes chamfered? "Blueprinted" block? Ion gas treatment? If you could do it all over again, what steps would you take?

I'm not in any rush to finish the whole car, and funds wouldnt allow it all at once anyway. So basically i'd like to do a very thorough build over the next year or two, not missing an opportunity to do something to improve the build but at the same time not wasting any funds on unneccesary steps.

I have very few posts but ive been lurking here following your build threads and learning since before I got the Z 2 years ago. I guess now that ive got some basic knowledge and the parts required i thought id reach out for some opinions on my specific project. Bottom end talk only boys, youll see what else ive got in store when the time comes And no im not sleeving it nor will i need to. Thanks!

streetzlegend

iTrader: (2)

I have those exact same components on my short block, here is a post I did on someone asking for something similar to your thread:
https://my350z.com/forum/7756789-post9.html

look over the whole thread actually, good info in there.

Armlocker

iTrader: (3)

I remember reading that thread when it was new, some good info on there for sure. I'm more curious about covering all the bases with the machinist. Things they wont do if you dont ask, that sort of thing. Should i try to find a machinist with the computer balancer or are bobweights just as good? "Blueprinting" seems a bit vague but im under the impression its just improving the factory geometry of the block, is there any specifics i should ensure are involved? Is it worth lightening the crank? Obviously i could ask the machinists all these questions but i'd rather get an honest opinion from people who ARENT trying to get my money lol

streetzlegend

iTrader: (2)

I wouldnt touch the crank other than balancing and polishing(if needed) the journals. "blueprinting" to me is a term most people arent even sure what it means, they balance crank and polish and think its blueprinted, you blueprint when you design a part that meets certain specifications, it can be either to match exactly how the manufacture intended it to be, or to custom specs, its more than just balancing, thats MY understanding of blueprinting.

Our cranks are well made, now it depends what kind of power your going with but even then, theres alot of guys here with really good power on stock crank. Just get it balanced, and polished and your good to go as far as crank goes (ofcourse making sure all the journals are within spec)

Zivman

iTrader: (19)

I read a while back (couple yrs ago) about someone doing knife-edging and nothing really decisive was discussed from my memory of the topic.

Leave the crank alone. Just balancing is all that is needed. Keep things simple. You start trying to more things and it just means more potential for problems. I would recommend getting the crank mag'd if you are getting up on miles on the crank you are using, have one of unknown origin, or you know it had been stressed.

I don't know how you could have bought bearings for your motor without having it cleaned, machined and mic'd? You buy bearings based the measurements of the components.

As far as blue printing a motor, it means NOTHING. all it means is your builder/machinist documented the specs on the build/machine work... that is all.

You need to find a machine shop/engine builder and have a discussion with them before you buy any more parts. Referring back to your bearings, you have no idea if they will fit properly... and then to go further did you buy stock size pistons? .020 over?

Armlocker

iTrader: (3)

Very low mileage on the components, no damage and very little wear. Ill have the journals polished but no need to be "turned" to change tolerance.

What potential problems can arise from having the crank lightened besides making it more difficult to balance?

Zivman

iTrader: (19)

You are installing new rods, this will change tolerances, and not every motor from the factory comes with the same size bearings.

lightening it means removing material, which will weaken it to some degree

streetzlegend

iTrader: (2)

Wanted to point out, just because the crank has no "wear" on it, dosnt mean you dont have to mic it and get the specs. There is a few different bearing sizes for the vq35, the crank has engravings that show which bearings that crank used based on color, etc... then u go to the FSM and see what bearings u need, and verify the acl bearings you got are within the spec's of the bearings shown in the FSM for YOUR crank.

Armlocker

iTrader: (3)

If need be theyll end up back on the marketplace here where i got them.

Has anyone seen a crank break at the counterweight?

Zivman

iTrader: (19)

I had cracks in my crank, but up front where the pulley mounts.

What are you hoping to get out of lightening the crank? You will not see HP gains, you won't see increased longevity - at least none that could be objectively measured. It will just be an added expense that really has no upside that could be quantified.

Armlocker

iTrader: (3)

Im not sure, faster revs? I dont think anyone would argue that reducing crank weight is a BAD thing unless its to the point of weakening it. Finding out whats worth doing and whats not is my goal with this thread. Maybe someone who thinks it would be an improvement will chime in? The less I have to spend the better

QuadCam

iTrader: (8)

exactly.....you don't to buy bearings until you have already had the block and crank checked and/or machined. then, you'll know what bearings you need. you are probably safe, but have everything checked for clearances!!!

Armlocker

iTrader: (3)

Of course. I wasnt going to just start slapping parts together. I just said i have bearings, if they DO fit then great. The thread is about what things could be done out of the norm to improve the shortblock.

I wouldve expected people to suggest lightening and knife edging and coolant passage mods and heat treatments, magic wand waving etc etc.

What about having the block "decked"?

How important is it to use a torque plate during honing?

thom000001

You would only deck the block if it wasn't flat/smooth.

I have a fully stock BLOCK, with just forged internals, ACL bearings, HKS Headgaskets, ARP L19's, and stock crank (everything balanced of course), and I make 900bhp (769rwhp)....and I have 10k miles no the setup (most driving was done at 540rwhp)

Tom

streetzlegend

iTrader: (2)

Why not just leave the crank alone and balance it? Dont try to experiment too much, the simpler you keep it the more success you will have.

In my block I redecked it because the surface had a few nicks and scratches, but was very minimal I was able to still use the stock head gasket, didnt need extra thickness.

Before i did any balancing and redecking, I took my block to another shop that had vq35 torque plates, it is recommended you do that just to be on the safe side. then you can do all the other machine work at any other shop since thats pretty standard.

if your using the HR head gasket then ofcourse you'd want to do the small modification at the coolant entrance to the block.

Zivman

iTrader: (19)

IMHO you want to be as **** about the block deck as possible. once built this is definitely one of the more pronounced potential weak points -> keeping the heads on and sealed. Use a torque plate for sure if you do deck it. If your shop doesn't have one, rent one from Sharif at Forged. That is what I did on my block

niZam

^ Noice, but how do you lose 131 horsepower?

Zivman

iTrader: (19)

just a estimate most likely.... figuring around a 15% drivetrain loss

Armlocker

iTrader: (3)

I wish, i'm near Toronto Canada. haha. Still trying to find a shop up here with a VQ torque plate.

I WANT to do as little as possible, just wanted to hear from people who have done previous builds if there is something they wish they did the first time.

I'm not set on a specific headgasket yet, whats the power limitation of the HR gasket?

streetzlegend

iTrader: (2)

I dont think anyone has reached the limit of the HR gasket yet, with L19's they can be as strong as any other gasket IMO, theres a dude running 9's with HR gasket and L19.


The best part about the HR gasket is the coolant passages, they are evenly distributed to all cylinder, vs. the DE which is on one cylinder. Plus its cheaper than any other gasket.

If i were to do my build again, I would have put L19's. I went with HR head bolts which should be good to about low 600's(there was headlift on someons motor north of 600whp). on my FWD I wont really have much usable power passed that, not even at 500. So im not THAT regretful but I still would have done the stronger studs just to know that i CAN make more power without worrying about head lift, in your case, try going with the strongest studs l19