Here's the deal,

I have a '02 Nissan Xterra with the VG33E engine. It's a family hand me down and I can't sell it. When I researched the engine, I found it to be one of the worst engines out there. I saw comments like "Power of a 4 cylinder with gas mileage of a 8 cylinder". My personal experience only verified this. I got crappy gas mileage of 16-18 mpg while struggling to go up an incline on the freeway. Most of the online material on the Xterra is on off roading and nothing about building the engine. I thought, "Well that sucks, I'll just have to live with it."

Recently, however, I found some old articles, specifically the "Project Pathfinder" on the internet way back machine that talked about improving the power and gas mileage.

http://web.archive.org/web/20071014215827/nissanperformancemag.com/august04/pathfinder/
http://web.archive.org/web/20071015001153/http://nissanperformancemag.com/january05/pathfinder/
http://web.archive.org/web/20071014215903/nissanperformancemag.com/february05/pathfinder/

I also found a post talking about the potential of a VG33E engine here:
http://www.datsun510.com/bbmail/2005-2/2240.html

After this I learned that Nissan motors are overbuilt and have tons of potential. They just need to be unlocked. The VG33E is no exception.

At the moment, I would love to have some work done on the engine. From my research, this is my compiled information:

Bolt-Ons:
-Header - either a doug thorley header, or an SLR

Engine:
-Port/Polish heads of a VG30E from a 91 Maxima, this would be done by DPR Racing
-Valve grind with backcutting on both intake and exhaust valves
-Infiniti Q45 (1990-1994) VH45DE pistons, giving 3.4 liters of displacement and the flat top dome gives a compression ratio to 9.6:1, up from the stock 9:1.
-Either reground oem cams, the aggressive JWT (jimwolftechnology) cams, or Nissan Motorsports 262 cams

(From mike kojima)
264 degrees of duration and .430" lift with 106 degree intake and 116 lobe center

ECU
-Either a Z31 ECU with a romulator, Infiniti M30 ECU, MoTec ECU, JWT ECU

Injectors
-Either RC engineering or from a 300zx

The problem is both of time and money. On August 15, I'll be moving to Baltimore, MD for my Ph.D and I won't have access to the automotive resources of Southern California. All projects must have a budget, mine is no exception. I'm willing to spend from 2-5k depending on what is done and the benefits. My target HP is around 250-280.

I need help to determine is what exactly I want done starting with the most important and then where can I get it done in a timely manner before I ship it off to the east coast. While I gathered the information you have seen, the sources may be outdated and I believe consulting some experts in the area first will give me the leads I need to get this project completed.

No, VG tech is about the same. I don't think you are going to make more than 220-230 crank hp NA on pump gas with an engine that has enough toque for a 4x4. Don't bother with a motec.

Smartbomb, I'm not quite sure what you are saying "No" to or what it is you are comparing. Also I'm not following the logic of "having enough torque for a 4x4" leads to not making "more than 220-230 crank hp NA on pump gas". Although not necessarily related to your point but note that my Xterra is just a RWD.

I'm crossing off the motec, thanks for the Tip.

I was meaning that VG technology has not gotten better since the series was done. If you built the motor for 250-280 NA crank hp, the engine will be unpleasant on a heavy truck with big tires, etc. It will have a high narrow powerband, rough idle, poor low speed driveabilty and forget towing or going off road.

If you were not going to tow, you could substitute JWT cams, build a 2.5" exhaust for it and have JWT tune the ECU for premium fuel only. This would make about 185 whp or around 230-240 chp.

I see. What about the services references, are they still in business and still the recommended place to go?

To clear things up a bit. The vehicle will be driven only on city streets, freeways, no towing, and no off road (at least no off roading you couldn't already do in a commuter car.) My horsepower ratings are in crank of course. I mentioned 250-280 HP as a target because that appeared feasible on the project pathfinder site. I am concerned with real world power and the RPM range I want to improve is from 2k-4k. If that means only achieving 230HP, that's fine.

What are your thoughts on the head porting and valve regrind?

Best,
Brent

In that case I recomend the same cams we ran, they are about 10-15 hp down from the JWT cams but they make a lot more power in the 3-5k rpm range. DPR does good work, just don't go too big, the VG loses torque fast as the porting gets bigger and bigger. Tell Dan where you want your power and he will do a nice job. Porting the upper intake manifold doesnt do much at this level so I don't recomend bothering. Porting the injecteor step out of the lower manifold helps a little bit.

As a note, we did make the same power and torque as a VG33R supercharged motor NA.

Ok so I've decided I'm just going to just do the performance camshafts. I'd do the headers but I can't find one that will fit for the Xterra. The ones for the pathfinder interfere apparently. I'm looking for a reputable shop to do the work. I want to also do the timing belt, pump, and other belts at the same time since its required for swapping the cams. I want to get this done before I ship my Xterra to the east coast.

I'm looking for shop recommendations in Southern California. I have a local shop but I'm concerned about tolerances since its a Nissan. Any tips?

Spencer lowe racing made headers but I hear they might be out of business. There is a place in Miami that might carry some.

http://www.4x4parts.com/catalog/

We use Technosqaure for all of our mechnical work, they are the offical MotoIQ shop. Ex Japanese trained TRD techs and fabricators.

Yeah can't find any SLR header distributors, they are out of business. http://www.race-dezert.com/forum/showthread.php?t=35735&page=2

That link you gave has these https://www.4x4parts.com/catalog/product_info.php?products_id=4879 but they are "off road use only".

Thanks for the referral.

I've looked pretty heavily into this too while trying to decide between a cheaper 04 Frontier or a more VQ40 07 Frontier to haul the family around- there really isn't much out there for the VG33. To really preserve the characteristics of a truck engine and still make good power, the only solution I could settle on was to apply boost. It could be done fairly inexpensively with a properly sized remote mount turbo setup, but you'd have to be up on your fabrication skills and be able to spend a lot of time tuning if you were to get it all together in a month.

I love the whole concept of turbos, but it takes a lot of work to take it to completion. The whole problem of thermal management would probably be the first important hurdle. You'd have to rework the hood and the components in there less you end up with melted internals.

Oh definitely- but that would be avoided by dropping the turbo in the back or in place of your cat if you fit it down there. If I end up boosting my Hardbody, one of the cheapo options I'm thinking of is just attaching the turbo to the bottom of the stock exhaust manifold.

I was thinking of an easy turbo using Z31 300ZX parts but the turbo would hit the steering box

I looked into that option too, with the same result from people online- problems with the steering box. I've never lined it up myself though.

I hope this isn't considered a post jacking, but I was wondering if anyone knew the stock injector flow rate for the VG33ER (Supercharged Frontier). I can't find any of this information on the web other than stock and replacement reference parts numbers...but no one seems to list the flow rate. SR20, VG30, and even KA24 have loads of info about the injectors, but nothing for the VG33ER.

The reason I'm asking is that I am also working on modding the VG33. I have a set of cams from the former SLR. The cams were actually cut by isky, to the spec of 262 (i/e) and .435", with a lobe center of 111.

For my current setup, the exhaust manifolds I'm using are from a 2003 VG33E, the exhaust itself is dual 2.25" from secondary cats back to a perforated core straight through dual in dual out. The pulley on the S/C is reduced to 2.3" given a max boost of about 12-13psi. The spark plugs are 1 heat range colder (NGK range 7).

Basically I'm just worried if the stock VG33ER injectors flow enough for the addition of the cams.

I think its 375cc but let me check for sure. Those cams work real well, they are the same as sold by Nissan Motorsports as well and one spec milder than the cams we used on project Pathfinder.

You might want to run a boost dependent regulator to give a bit more fuel.

The regulator on the truck is already connected to the plenum pressure, so the fuel pressure rises with boost. I want to do a 3-stack wide laminova I/C as well, but I have to figure out if I have enough clearance (hood), or else I will have to do a body lift.

I'd appreciate the double check on the injectors. Thank you very much for doing that.

I mean a rising rate regulator with a step up like an FMU. For slight increses in fuel flow, they work really well.

Ah gotcha. Any suggestions for a decent FMU, at least a reliable one that is?

Forgot to add, what do you think of the BEGI/Cartech 2025 with the adjustable onset and rate of gain? Or would you suggest a fixed rate of gain (something low like 2:1). I figure any of the FMU setups will be around $200 or so.