It's not so much as need but do you really want to buy all old stuff to but into a build? That just seems like asking for it to fail. If wanting to do that I'd definitely recommend VHR swap or boost because I'm almost willing to bet both will outlast the one built with all old components.

 

Stock HR and VHR crankshafts are now about $1,500! (were 1K a year ago).

 

That HR or VHR oem crank now costs about $1,500; up $500 in past year.

 

VHR stuff is good well past 500hp/500ft-lbs.

I think the bigger question Dark was asking is - yes, the OEM components are plenty strong but what are you using pistons that have been mated to a specific engine / cylinder wall. If not, your best bet will be to hone the block, get new rings, and re-bed rings. I would assume you’d put new bearings in?


Just bought a replacement DE crank for $200/shipped that came off a 2014 maxima … Didnt realize the VHR stuff jumped up s so quickly??

 

I am assuming $1500 new.
That's the ticket here? I feel like the way OP is thinking of it is buy HR and used VHR parts and use a mishmash of old parts....I'd be worried about reliability, even at 350whp. Better of getting a stock VHR to swap in.

 

Oh and @bealljk Z1s Z is putting out 566whp but I think that's about the limit of reliability according to AMS (which I trust more than Z1)

 

You’re probably right … a few on ebay, used for $400 to $600 … could be worse!

Yea, I think most the reliability goes out the window when you open the block up

566hp out of a 3liter isnt bad at all…sorta what the built z32 were doing - right around the 600hp mark.

 

Sorry I wasn't clear with what I said. $500 for the crank, $500 for the rods. I haven't checked those prices in the last month or so.

 

The plan was a good used HR engine, and a new VHR crank/rods/bearings.

 

I had thought that if I purchase an HR rather then the VHR the stock HR pistons are bedded to that block, and I could avoid having to get new rings and hone the sleeves. Furthermore, that brings me to the head gasket question I had asked originally. I'm unsure if the previous people who have put the VHR crank in the HR block were using stock HG or not? Also, I am not familiar with the HR engine enough to know if pistons can be installed from below, saving having to pull the heads. This can be done on some engines, but I don't know about the HR

 

I dont think the pistons can be installed from the bottom side … I think theyre drop-in and connect to the crank … I am almost certain the girdle would interfer.

I think your best bet is buy a VHR and find HR heads … that’s what the people that I know have done. I dont think you use the HR block … I think you only use the HR heads/cams/valves/etc …

And I would go with an OEM head gasket - it’s not going to make a difference (the added volume) all things considered. You would be wise to put ARP 2000 / L19 / 625 head studs in but this will obviously add some cost.

 

Yeah had a closer look at the HR/VHR blocks. Castings for the girdle support structure wouldn’t allow pistons to be installed from below. So the heads are coming off no matter which block I start with. Since that is the case, I think I agree with the above. Prices for used VHR’s are the same as HR’s, and I can probably pick up hr heads and pistons, for less then the VHR crank and rods.

 

Are the pistons the same between the HR & VHR?

If it was me, I’d find a good/great condition VHR with good compression, no issues and leave it alone. Remove heads, new head gaskets, head studs, and put the HR heads on the car.

I wouldnt economize on the VHR block - buy a really good one, even if it cost you more money upfront, then find clean HR heads … just my 2cents

 

The HR pistons have to be used to clear everything. The VHR pistons don't work with the HR heads.... or so I am told from a few different sources.
Here is a good video showing the 3 style pistons. The VHR pistons do not have valve reliefs on both sides of the piston face like the HR pistons do. I believe that the wrist pin height differs between them as well. There is also a difference in rod length between the HR/VHR

 

You may want to research it a little bit … messaged my buddy who did the VHR/HR hybrid and he said he used the VHR block and VHR internals… so maybe some mis-information and you’re making it harder than it needs to be. Proceed accordingly!

 

It is VHR crank and rods with HR pistons. VHR and HR blocks are the same.

 

I can't see the VHR having lower lift, I'll watch that video when I'm out of work but I think the .2 is the reason it wouldn't need reliefs. I still think a pure VHR swap is the best option.

 

I would go for the VHR if it could be swapped into a G35 with full functionality, but as of right now it cant. The HR can be however. Currently, the following function are lost when swapping a VHR into the older DE chassis cars.

• Check engine light
• Automatic radiator fans
• AC
• Cruise control
• Traction control

 

Is this due to CAN communication issues?

For perspective … Im running a Link G4+ and I manually control my fans, the traditional OBD2 isnt used (link has their own diagnostic code system - that is 10x better than obd2), havent had AC is decades, I dont use cruise, and link has a rudametric form of traction control … so, it’s not the end of the world if you lose those items (if you ask me)…

 

From what I understand, yes it is a CAN communication issue. For me I don’t think I have the budget or the know how to transition to a stand alone ecu system. Having to manually control the cooling fans seems like a disaster waiting to happen imo. I’m not into the race car thing, done that in past cars. I like having all the features and comforts of the car. Maybe I’m getting old 🤔