Tuning Feature: Nissan VR38DETT Modified

"Comprehensive guide to tuning the Nissan VR38DETT engine!"

We are regularly getting posts asking how to improve the VR38DETT from people wanting to know what are the premier VR38DETT modifications. So let us look into Nissan VR38DETT mods and outline the best modifications on this great engine and point out some potential pitfalls along the way.

The Nissan VR38DETT are good project engines and with carefully picked modified enhancements like remapping, turbo kits and camshafts you will substantially improve your driving pleasure.

Our aim here is to examine the options for your VR38DETT tuning and highlight the best mods that work.

Just because particular modifications are are common on VR38DETT it doesn't mean it is good, we will focus on the top modifications to provide your VR38DETT with the best power gain for you money.

Significant power hikes can be made on engines, and the VR38DETT is no exception, with cam upgrades. Altering the cam profile alters the intake and exhaust durations on the engine and can dramatically change the bhp and power output.

NB: Fast road camshafts normally boost the torque over the rpm range, you could drop a little low down power but top end will be better.

Motorsport camshafts, boost the top end band but as a result the car will not idle smoothly and low end power nearly always suffers.

On a typical daily driver one, ideally, must carefully try to optimize your power band to your typical driving style.

I'd never have ever thought a VR38DETT Competition cam is a pleasure to live with when driving in heavy traffic.

Different VR38DETT engines respond better to less aggressive camshaft durations so view each engine as unique.

The ECU mapping and injectors and fuel pump also will make differences on the torque gains you'll get.

Longer valve durations can alter the torque 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.

VR38DETT Tuning Stages

Stage 1 VR38DETT modifications: Fast road camshaft, Remaps/piggy back ECU, Intake headers, Sports exhaust manifold, Panel air filters, Drilled & smoothed airbox.

Stage 2 VR38DETT modifications: Fast road cam, induction kit, Ported and polished head, fuel pump upgrades, high flow fuel injectors, Sports catalyst & performance exhaust.

Stage 3 VR38DETT modifications: Engine balancing & blueprinting, Competition cam, Twin charging conversions, Internal engine upgrades (head flowing porting/bigger valves), Adding or Upgrading forced induction (turbo/supercharger), Crank and Piston upgrades to alter compression.

Remaps allows a tuner to release the full potential of all the tuning parts you've done to your VR38DETT.

It will usually give around 30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but your results often depend much on the tuning parts you've done and the condition of your engine.

Pushing air into each cylinder is the whole point to any tuning job.

Intake manifold carry the air from the air cleaner and allow it to be fed into the engine and mixed with fuel.

The bore size, shape and flow characteristics of the Headers can make a big difference to to fuel engine efficiency on the VR38DETT.

Commonly we find the headers are improved through performance upgrades, although some manufacturers provide fairly well optimized headers.

Adding a VR38DETT larger valve kit, getting VR38DETT port enlargement and head flowing will also raise torque, and importantly will give you a better torque increase on other upgrades.

Turbo upgrades for the VR38DETT

NASP engines need quite a lot of work when you add a turbo, so we have a separate guide to help you take into account the pros and cons of going this route on your 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.

When your motor is fitted with a turbocharger parts are giving better power gains and most turbo charged engines will have stronger components.

There are tuning limits for every engine, with some being very over engineered and some only just able to handle stock power

Research these limits and install better pistons and crank to handle the power.

We see many tuners spending a lot of money on turbo upgrades on the VR38DETT only to have the car literally blow up when it's been enthusiastically driven.

Large turbochargers tend to suffer a bottom end lag, and small turbochargers spool up really quickly but won't have the top end bhp gains.

Thankfully the range of turbos is always improving and we now see variable vane turbos, permitting the vane profile is altered according to speed to lower lag and increase top end power.

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

You'll commonly see there's a limit in the air flow sensor MAP/MAF/AFM on the VR38DETT when considerably more air is being sucked into the engine.

Going up you'll find 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor limited power at a much lower level.

Adding a supercharger or additional turbo will make large torque gains, although harder to setup. We have this article covering twinchargers if you want to read more.

Uprating VR38DETT fuel injectors

Don't forget to boost the fuel system when you are increasing the torque - it makes the car more thirsty. It makes sense to be generous with your flow rate on the injectors.

The accepted safe increase is to add another 20% when buying an injector, which takes into account injector deterioration and gives a little spare capacity should the engine require more fuel.

We think this one is common sense, but you'll need to match your fuel injector to the type of fuel your car uses as well.

Best VR38DETT performance exhausts

You should look to improve your exhaust if your exhaust is actually creating a flow problem.

On most factory exhausts you should find that the exhaust flow rate is still good even on modest power gains, but when you start pushing up the power levels you will need to get a better flowing exhaust.

Sports exhausts will certainly help air flow through the engine but do not go too big or you will reduce the flow rate. Stick to 1.5 to 2.5 inches as a rule of thumb.

Typically exhaust restrictions are traced to the emissions filters installed, so adding a faster flowing performance alternative will help avoid this restriction.

Problems and issues to look out for on the VR38DETT

The VR38DETT engines, if regularly serviced and maintained, are generally very reliable and have few issues. {But if neglected they can cost a small fortune|When neglected they get very expensive to run|They can however be quite expensive if neglected| }

Regular oil changes are vital on the VR38DETT, particularly when the engine has been modified and is putting down more power than the manufacturer intended.

For more information on Tuning your VR38DETT engine please join us in our friendly forum where you can discuss tuning options in more detail with our VR38DETT owners. It would also be worth reading our unbiased tuning articles to get a full grasp of the benefits and drawbacks of each modification.

We need your help to complete and improve this page, so do give us your feedback in the comments box below.

We really like hearing from our readers, and hearing about which upgrades were the most effective for them, it helps us improve our recommendations and articles to reflect current trends in modifications and ensures that our VR38DETT guides and tips are kept up to date.

Please Check out my YouTube channel, we're regularly adding new content...

Click to accept YouTube Cookies & Play.

This article is flagged for an update, so please pass on specific tips below that I can include. All articles, and content was written by me, Waynne Smith TorqueCars founder. Some outlines are just too general so I appreciate your feedback and suggestions. This entry was filed under Nissan. You can leave a response below or join our forum to discuss this article and car modification in detail with our members.

If you liked this page please share it with your friends, drop a link to it in your favourite forum or use the bookmarking options to save it to your social media profile.