Tuners tips on "VR38DETT Modifications"

VR38DETT Modifications Guide

How to modify and upgrade the Nissan VR38DETT

"Comprehensive guide to performance parts and tuning the Nissan VR38DETT engine!"

Sites like TorqueCars are frequently getting messages requesting info on how to improve the VR38DETT from people inquiring about getting more power from the VR38DETT and wanting to know what are the ultimate VR38DETT power upgrades. So let us look into Nissan VR38DETT mods and outline the best mods that work on this great engine and point out some common pitfalls along the way.

Now we will examine VR38DETT tuning and point out the premier modifications for your car. Nissan VR38DETT are fantastic to work on and with a few sensible tuning mods like remapping, turbo upgrades and camshafts you will positively maximize your driving enjoyment.

Just because particular modifications are appear in lots of VR38DETT projects it doesn't mean you should fit it, we will focus on the best modifications that will give your VR38DETT the best power gain for you spend.

Without us subscribing to the common myth of 'if it's shiny and makes more noise it must be good' you seem to get in many tuning magazines and on car forums'.

VR38DETT induction kits

Improving air intake on the VR38DETT

You need air matched to fuel for an engine to work. If there is a lack of fuel then it will run lean, if there is not enough air it runs rich resulting in lost power and potentially damaging the engine. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Pulling more air into your VR38DETT is the whole point to any engine modification project.

It is not unusual that there is a restriction in the air flow sensor MAF/MAP on the VR38DETT when loads more air is being fed into the engine.

We see 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor limited bhp at a much lower level.

Intake flow the on the suck phase from the air cleaner and allow it to be drawn into the engine cylinders with fuel for the squish phase.

Design and rate of flow of the Plenum can make a big effect on to fuel mixing and power on the VR38DETT.

Most intake are in dire need of performance upgrades, although some manufacturers provide fairly well optimized intake.

Fitting big valve kits, doing some port matching and head flowing will also lift bhp, this will raise potential for a greater bhp increase on other tuning parts.

VR38DETT performance cam tips.

Different VR38DETT engines respond better to mild camshaft durations than others.

The ECU mapping and injectors and fuel pump also will say much on the power gains you'll achieve.

Altering valve durations can alter the power band and on most engines the exhaust and intake durations do not need to match, although most cams and tuners use matched pairs there are some advantages to extending the intake or exhaust durations.

Significant air intake, and exhaust improvements on the VR38DETT can be made from cam upgrades. Changing the cam profile alters the intake and exhaust durations on the engine and can dramatically change the bhp and power output.

NB: Fast road cams tend to raise the performance through the rev band, you could sacrifice a little bottom end torque but top end will improve.

Race cams, raise the top end band but as a result the car will not idle smoothly and low end power nearly always suffers.

On a road car you must carefully try to match your torque band to your usage of the car.

I would be surprised if you have found a VR38DETT Motorsport and race camshaft is a pleasure to live with when on the daily commute.

Stage 1, 2 and 3 mods for the VR38DETT

Stage 1 VR38DETT parts:

Sports exhaust manifold, Fast road camshaft, Intake headers, Drilled & smoothed airbox, Remaps/piggy back ECU, Panel air filters.

Stage 2 VR38DETT parts:

fuel pump upgrades, Fast road cam, Ported and polished head, induction kit, Sports catalyst & performance exhaust, high flow fuel injectors.

Stage 3 VR38DETT parts:

Crank and Piston upgrades to alter compression, Twin charging conversions, Adding or Upgrading forced induction (turbo/supercharger), Internal engine upgrades (head flowing porting/bigger valves), Engine balancing & blueprinting, Competition cam.

The VR38DETT engine blocks are great to work on and we note that there are quite a few choices of mods and tuning parts out there.

Remaps should help to to establish the full potential of all the parts you've done to your VR38DETT.

You will typically expect to see gains of approximately 20-30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but the end result may differs on the parts you've applied and the condition of your engine.

Tuning tips and articles Engine tuning Transmission tuning Care care Intake & exhaust mods Improve handling Forums

Turbo modifications on the VR38DETT

To get a turbo working on a NASP engine there is a lot involved, from lowering compression ratio to improved fuel supply and mapping, so we have found a great guide to helpavoid the common pitfalls or end up with an unfinished project because you were not told what you were getting into by doing this on the VR38DETT.

The more air you can get into an engine, the more fuel it can burn and uprating the induction with a turbocharger upgrade makes superb power gains.

If the engine has a turbo already fitted parts are going to make more power and you'll see that turbo charged engines are built using more solid components.

However most engines will have power limits

Research these limitations and install better pistons and crank to utilize the power.

We see many drivers spending a lot of money on turbocharger upgrades on the VR38DETT only to suffer the humiliation of seeing the whole thing catastrophically fail soon after it's used in anger.

Larger upgraded turbo units often suffer no power at low rpm, and smaller turbo units spool up quickly but do not have the peak end bhp gains.

Over the last 20 years the range of turbos is always moving on and we are seeing variable vane turbos, permitting the vane profile is altered according to speed to lower lag and increase top end performance.

Twin scroll turbos divert the exhaust flow into a couple of channels and push these at differently profiled vanes in the turbo charger. They also increase the scavenging effect of the engine.

Beefing up the air intake by adding a supercharger or additional turbo will help you achieve very large bhp gains, although more challenging to get working. We have this guide to twinchargers if you want to read more.

Tips about fuel supply on the VR38DETT

You will need to ensure that the engine is not starved of fuel so need to ramp up the fuelling when you start going beyond 20% of a torque hike. We would recommend you to over specify your injector capacity.

The accepted safe increase is to add 15% to the flow rate when fitting an injector, helps cope with injector deterioration and provides a bit of spare capacity should the engine require more fuel.

Don't forget that different fuel grades will usually require different settings, a high octane fuel will burn more efficiently than lower octane fuel for example. A car will trim fuel supply to keep within the ideal air fuel mix but at the extreme ends you may need to adjust your injector capacity, or the mapping or you'll get flat spots and potential lean or rich fuel issues..

Recommended VR38DETT performance exhaust upgrades

You may need to boost your exhaust system with an upgraded one is if your current exhaust is actually causing a flow problem.

On most factory exhausts you'll find the flow rate is still good even on modest power gains, but on a serious tuning project with a big boost in power you will certainly need to get a better flowing exhaust.

Please dont run with the largest exhaust you can buy you'll reduce the exhaust flow rate - the best for power gains are usually between one and a half to two and half inches. Your exhaust design, the bend angles and construction are what have more effect on flow rates than your pipe width to a certain extent. So the exhaust design is a big factor.

Usual exhaust restrictions come around the catalyst installed, so adding a higher flowing performance alternative will help avoid this restriction.

Catalyst removal (NB:catalysts reduce harmful engine emissions) is illegal in most countries and regions.

Faults issues and things to look out for on the VR38DETT

Like most engines an VR38DETT, should have few issues if it gets properly serviced and looked after.

We cannot stress enough the need for oil changes with the correct grade of oil on the VR38DETT, failure to do this will exacerbate engine wear, on a tuned VR38DETT this is more important than ever and close attention should be paid to your maintenance schedule.

If you are interested in learning more or getting impartial tuning advice for your VR38DETT why not pop over to the forums at TorqueCars where you can chat about VR38DETT tuning options and read about others projects who may be planning to do similar modifications on their VR38DETT.

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