4.0 NA Build (future turbo setup)
 

So I am planing to build a VQ35 to swap my original motor some time towards the end of this year.
The build is going to consist of:
- Tomie Cams
- Wiseco Forged Pistons 9.5:1 CR
- Carrillo Rods
- Darton mid sleeves 100mm bore
- Upgraded Main, Rod Bearings and Thrust Washers
- OEM crank from VQ37VHR

This will put the car at 4.0 displacement, I plan on boosting the car the following year after i save up for the Kit. Does anyone have any ideas how the car will run NA with this type of setup? Its a pretty big boost in displacement but I'm using lower compression pistons due to wanting to boost it in the future. Are there any NA setups out there with such a high displacement that anybody knows of?

I havent seen many if any ... whats the duration on the cams you intend to run?

what are your power goals once you hit 4liter NA and then 4liter FI?

single or twin setup?

pump / E85 / race gas?

what valve work are you planning?

Do you fear any cylinder wall distortion once you're bored-out and pushing boost?

does weisco make a 100mm piston? or is this a special order? 2.5mm seems like a lot to take off the OEM cylinder walls and apply boost and expect some sort of longevity to this? Why 4liter?

are the rods sized properly for the VHR crank?

what are you going to tune with?

how much money do you have to spend?

be sure to get extra oil clearance on your bearing sets - which bearing set are you going to run?

Probably going for pump gas, the block is getting sleeved so I'm not boreing the stock walls, I have not planned much headwork other than the aftermarket cams and springs, and will be doing a twin turbo setup. You can buy the 100mm piston from z1. And the rods are going to be aftermarket rods for the 37VHR yes. Cams 262 duration w 12mm lift. Looking for something between 5-600hp when boosted. If that happens with little effort I will go from there.

If you're doing all this work you mise well go all out.
500-600 is nothing for the stock displacement and sleeves.
If you're spending the $5-6K it looks like you're going to spend on the bottom end you should shoot for 800-900whp

For the price of cams and bottom end work no way you should go under a 272 duration 12mm lift.
Since almost all new cams are ~$1.3K, the JWT C8's is where i would start.

Also remember a good port and polish will put you on par with a set of stock HR heads. So spend the extra there if you have it.
https://www.onpointdyno.com/vq35-hr-vs-de-head-flow/

You have to remember the heads is where you make or don't make power.

You are venturing down a very very expensive path to do this correctly i hope you know this my friend.

Cool - sounds like you got a good game plan ... let me be the first (probably not the last) to save you $5k to $7k and a metric ton of anguish...

you dont need 4liters to make 600hp on this engine. You need a $5k to $7k built block that can take 18-20psi of boost and the other items youve mentioned.

I ran 17psi and made 568hp and I ran out of fuel. Many many people have made more than 600hp on OEM displacement. Any respectable twin kit will easily push 20 to 24psi of boost.

Obviously this is your build and you are 10,000% free to do what you want. If I was in your shoes (and I am at the moment) - I would:

get a good 3.5 VQ block (you probably already have one in your current engine).
Ensure the crank is good - get it ground & polished if need-be (might be wise).
Get +.001 oil clearance bearings (like the ACL HX).
Get aftermarket rods that are good up to 1000hp
Get aftermarket pistons that are good to 1000hp.
Keep the 262 cams - those are fine ... they'll provide plenty of flow with the VTC. If you wanted to go a little more aggressive, no one would blame you. Valve work would be an option but wont keep you from your power goals. And yes, quality springs/clips/retainers
Assuming you have a DE, consider getting a Rev-up oil pump.
You'll need $1k to $2k for an ECU and tuning (if not a little more)
Add other fun things like an oil cooler, dampening crank pulley, billet girdle,

Assuming you've already consider a clutch/flywheel kit?

and of course a twin kit/intercooler?

did you mention a budget youre prepared to spend?

budget is in the 10-15k range, thanks for all the info guys.
Just to clarify for everyone my motor is an HR
Honestly most of the bottom end work is for reliability. Im sure I could just slap a TT kit on the stock motor and make my power goals but I want it to last for a good while as a daily driver. I have read a million times over that the stock sleeves will not hold much more than 10 psi for any real length of time.
And yeah the 4.0 may not be worth it.. Im just tired of waiting for Nissan to make a 400z :icon17:

You mentioned aftermarket ECU is the uprev not sufficient? I have read a lot of good things about the stock ECU tuning capabilities.

Also on the TT kit, does anyone know if there is anywhere I can purchase turbo manifolds only? It seems like turbo kits for the HR run 10k.. and I have a hard time wrapping my head around spending 5-6k on a built motor but then spending twice that for the TT kit.

I'm out!!

really? Am I understanding you right - the HR block cant do more than 10psi long-term but the DE can take it? Ive always been under the pretense that the HR is essentially better at everything (but it's a newer architecture).


I don't know as much on the HR platform as the DE and I like Uprev but I'd opt for an aftermarket ECU. Id want to tune off VE/MAP vs. MAF and all the newer ECUs are going to have many new features that are out of the scope of Uprev. But maybe Uprev has those abilities on the HR ecu.


I'd keep an eye on the secondary market - they do come up but not very often.

100% stock HR is good for like 550 turbo whp all day long.
The engine is way way more stout than the DE.

Most people say that you shouldn't push the stock sleeves past 600whp, but it happens quite often.
I vaguely recall of only two times that people have had problems with stock sleeves cracking but that was at like 800+whp

Get a hold of boosted performance and buy his mid mount turbo kit. ~$7k or so and NEVER look back.

If you are wanting control of EVERY aspect of the engine and traction control then a stand alone is what you need.
If you moderate control of the engine and no real traction control tuning (Still have stock T/C) then uprev is what you want.

The new ARC feature of uprev is sweet, Flat Foot Shifting, Rolling Anti-Lag, Anti-Lag, and Standing Burn outs.

It's seeming like you have a lot of decisions ahead of you, and even more research.

Sorta … I don't think theres a standalone that can replicate Nissan OEM VDC (Vehicle Dynamic Control) if you want to count this as traction control...I was pretty bummed when I went Link that it has many many parameters for front wheels : rear wheels traction control but nothing that's gonna save my butt when I do something unsmart such as taking a turn too fast (meaning when the left wheels are moving at inconsistent rate with the right wheels for a given steering angle)

Oh i get what you mean, that didn't even cross my mind.

didnt cross mine either until the OEM ECU was out of the car!

you can search.....but from my recollection......there were way more people that had issues with sleeves........even when installed by Darton themselves........then success stories. In fact, I can't rem ONE that had luck for long with sleeves.

I would ask whoever is going to build your engine and see what they will stand behind.

I also think traction is going to be more of an issue about 500-600hp than the benefits of having a higher hp goal.

Well thanks for all the info guys, Looks like I have plenty of research to do still.