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Discussion Starter · #23 ·
lets just cut straight to it and swap a vq37hr into an X!?
G37 has plenty of low-end torque factory-stock, but it's not similar at all to our engine. G35 owners can't swap in vq37...that was probably intentional to keep folks buying new cars.
If Nissan wants to start putting vq37s in trucks...
 
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A couple years ago I made 238 whp untuned. I had the plenum spacer, volant intake with different filter, Doug thorley longtubes, no cats, lightweight flywheel from jwt, fuel pump wired to relay with 12g wire. 285/75r16s
 

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Discussion Starter · #25 ·
Just curious...why get long headers on an off-road truck? You just want to delete your cats?
I thought you wanted to haul stuff, climb over stuff....seems like shorties are more geared towards that. Long headers are for racers hanging out at the redline.
 

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Shorties are for higher rpm...you want longer tubes as your primaries (e.g. LT's) for lower to mid torque gains.

I'm happy with my LT's and the exhaust's performance, although mine is too loud for my tastes. It can be fixed and will, just saying...

Haven't dyno'd my X, but did my 2011 Frontier P4X for an IMS test and it put out some respectable numbers (even stock). Will see if I can find the actual ones and update later.
 

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Supercharger!


Sent from my iPhone using Tapatalk
 

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Shorties are for higher rpm...you want longer tubes as your primaries (e.g. LT's) for lower to mid torque gains.

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Possibly things are different with V6 applications, but on V8's this wouldn't be true.

Rule of thumb for V8's
Shorties work best for idle to mid range and are a best option for daily driven vehicles which rely on low rpm power.

Long tubes work best from midrange to high rpm applications. If your planning an engine around high rpm and moving a lot of exhaust effectively, long tubes are your best choice.
 

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Discussion Starter · #29 ·
Shorties are for higher rpm...you want longer tubes as your primaries (e.g. LT's) for lower to mid torque gains.

I'm happy with my LT's and the exhaust's performance, although mine is too loud for my tastes. It can be fixed and will, just saying...

Haven't dyno'd my X, but did my 2011 Frontier P4X for an IMS test and it put out some respectable numbers (even stock). Will see if I can find the actual ones and update later.
Other way around, generally. Shorties give you low-end tq, possibly at the expense of high-end tq. Which is fine by me. Living in the foothills of the Appalachians I can be going 25mph and suddenly wind up at 2700rpm just from incline on the road.
Also my dad just bought a big tract of land so I'm towing stuff there a lot.
 

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Highest I've seen in all my searching is:

503hp/468tq

But that dude has a full blown race engine with triple 40mm webber carbs.


I currently have:
Volant Cold Air Intake
XTP Intake Manifold Spacer
Doug Thorley Long Tube Headers
High flow cats
Deleted y-pipe
Magnaflow muffler
UpRev Dyno Tuned

My Dyno Numbers:
241.2 HP
263.4 Torques

Most of these parts don't drastically improve your "Max" numbers. What they do is flatten out your torque curve. In stock form the VQ40 makes peak torque @ 4k rpm. With all these modifications My torque curve is around 240 @2k and peaks at 263.4 @ around 5k rpm greatly increasing drivability and useful torque.

A word of caution: I did all of these modifications, and didn't immediately dyno tune. When I finally got to the dyno the techs said that the X was running very lean. So if your doing more than CAI and a muffler, you should really tune the truck ASAP.

I want to give a hat tip to: 5l33p3r for his write up: How-to: DT Long Tube Headers Installed w/Dyno #'s
wow, 20 hp in gains. I'd expect more from all of that. What elevation are you at?
 

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Holy $#/!balls people. The frackin VQ, VK and VRs are ALL the same thing for the most part. VR38DETT crank, rods, pistons, and heads will go DIRECTLY into a VQ40 block. Bore spacing on all of those models is 112mm, that's 4.409 inches between pistons center to center. Small block/LS/LT Chevy is 4.4 inches. The Deck height on the VQ35 and VQ37 is the same. The Deck height on the VR38DETT and VQ40DE is the SAME.
The reason why your Xterras and Frontiers and Pathfinders don't make any power with bolt ons comes down to one thing, the brain. You buy huge intake pipes to get the air in, headers to get the exhaust out but you never changed the brains of the operation. THE CAMSHAFTS CONTROL RPM AND POWER. VQ40DE Factory cams are tiny. Very short duration for off idle torque. JWT makes the best cams for Nissan. JWT is Jim Wolf Technologies. Change the cams, change your life. Try 350hp easy with the supporting mods you've already done. If you're feeling really ambitious, VK56 heads can be made to fit an LS. Even an LS7.
 
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