The Guide to the Dodge Neon Turbo. When the Dodge Neon initially hit the streets in 1993, Chrysler had no idea it would become so popular among the aftermarket tuning community. At the end of the day, it was designed to compete with international econoboxes like the Toyota Corolla and Nissan Sentra, but with a slight performance edge. In the United States, the Neon was marketed as both a Dodge and a Plymouth, with the former lasting far longer in the imaginations of enthusiasts than the latter. There are actually two generations of the Neon, the first from 1993 to 2000 and the second from 2000 to 2005.
The quasi-sporty aspect of the Neon, along with its general availability, formed a perfect storm that brought the tuning community to the table. The 2.0L Chrysler 4-cylinder engine found in the Neon was already punchy, producing 132 horsepower in SOHC form and 150 horsepower in DOHC form. When the 2.4L turbocharged SRT-4 Neon was introduced in 2003, the cogs in the minds of 2.0L Dodge SX owners who desired a piece of the turbocharged pie began to turn.
The 2.0L Neon turbo formula is well-established at this point. Since the release of the Neon, enthusiasts have established a solid, tried and true formula for reliably turbocharging the Dodge 2.0L engine. In this post, we’ll go through the fundamentals of building a Dodge Neon turbo.
What kind of power can a Dodge Neon Turbo handle?
When asking this question, there are several factors that must be considered. There have been numerous instances of turbo Dodge Neons producing as little as 300 horsepower, while some hobbyists have achieved 600 horsepower on a stock 2.0L bottom end. The distinction is due to tuning and preventative measures such as updated fuel systems and piston cooling techniques. If you’re searching for a safe level, the 300whp mark is usually where preventative steps should be taken.
If you intend to use OEM internals, you should consider strategies to keep internal temperatures as low as possible to avoid detonation within the cylinders. Installing a water/methanol injection kit on your Neon is a common way to accomplish this. A water/methanol system lowers air inlet temperatures while improving octane. This drastically reduces the possibility of explosion and may even enhance horsepower slightly. Change the standard Neon spark plugs for cooler ones to help lower cylinder temperatures.
You’ll need to update to forged internals if you want to push more than 8psi of boost. To accommodate the higher boost, pistons and rods will need to be modified. The most common piston option for the Neon is JE forged pistons, which can be obtained in a low-compression standard that delivers 8.5:1 compression in DOHC Neons. JE pistons are frequently used in conjunction with forged Neon Eagle connecting rods. Forged pistons and rods can handle up to 600 horsepower when used together.
SOHC vs DOHC in the Dodge Neon Turbo
The camshaft arrangement is a major consideration when it comes to Dodge Neon power potential. The original model Neon (1993-1999) was offered with a SOHC or DOHC 2.0L Dodge 4-cylinder engine. The DOHC arrangement was dropped for the second generation Neon (2000-2005), which was only offered in SOHC version. The cylinder head is the fundamental distinction between the SOHC and DOHC Dodge 2.0L engines. The pistons are also slightly different, although the performance difference is primarily due to the DOHC’s higher flowing head.
The internal compression ratio differs between SOHC and DOHC engines due to cylinder head differences. The compression ratio of DOHC Neons is 9.6:1, whereas the compression ratio of SOHC Neons is 9.8:1. The lower the compression ratio, the better for turbo applications. As a result, DOHC Neons with factory internals are better able to manage boost. However, if you own a Neon with the SOHC 2.0L engine, all is not lost. In reality, a DOHC cylinder head mated with a SOHC block and internals would be the ultimate Neon turbo arrangement. At 9.3:1, this configuration provides the lowest compression ratio. This is the ideal boost configuration because it allows you to run the maximum boost levels with stock internals.
If you have a SOHC Neon and want to do this franken-swap, you’ll need to swap out some extra parts. A DOHC intake and exhaust manifold, a DOHC wire harness, motor mounts, injectors, and a fuel rail are the main components.
Check out this guide at DodgeForum.com for more thorough information on performing the SOHC to DOHC conversion.
Engine Control for the Dodge Neon Turbo
In contrast to many other turbocharged vehicles, which rely on either an improved engine management system or a piggyback tuning solution, the standard ECU is frequently retained in mild 2.0L Turbo Dodge Neon modifications. Having said that, changes are still required to allow a standard Neon ECU to function properly with a turbo added.
Voltage Clamp / Missing Link
A missing connection or voltage clamp is one of the most prevalent ways to avoid the need for aftermarket engine control solutions entirely. While they operate in different ways, both devices accomplish the same task. They both prevent the factory PCM from detecting the presence of boost. A lost link is a mechanical component that prevents the MAP sensor from detecting boost. A voltage clamp operates in a slightly different manner. It is an electrical component that prevents your MAP sensor from providing a signal to your PCM indicating that your engine is receiving boost.
The factory Neon PCM runs normally if no turbo is fitted since it does not register a change in air/fuel ratio. Of course, if your Neon’s fuel system was not properly modified, it would run terminally lean. In the following part, we’ll go over the correct fuelling modifications.
Fuel System for Dodge Neon Turbo
Fuel management is one of the most important aspects of any turbocharged system, and the Neon is no exception. When changing your Neon fuel system for a turbocharged application, you have two options. We’ll get to those in a moment. However, first and foremost, an upgraded fuel pump is required. The most frequent fuel pump improvement for turbo Neons is an in-tank Walbro 225. The 225 can provide enough fuel and pressure for most 2.0L Neon turbo setups.
Aside from the fuel pump, a Neon turbo system requires a method of regulating fuel flow through the system. Modifying the fuel pump canister to work with a rising rate fuel pressure regulator is one option. In the turbo Neon community, this is commonly referred to as a “spool-boy” mod. A rising rate fuel pressure regulator adjusts fuel pressure in response to boost pressure. A “spool-boy” mod eliminates the requirement for a modern digital fuel management system in favor of an analog method of regulating fuel pressure. For additional information on the Neon “spool-boy mod,” see this website: Neons.org.
FMU has been improved.
The other alternative is to go modern with a computerized fuel management system. Surprisingly, this is the less popular route taken by turbo Neon drivers. The mostly analog “spool-boy” and RRFPR method works well. Having said that, there are a few benefits to employing a computerized system. It will control the fuel injectors’ response to boost with an aftermarket Neon fuel management device. An FMU, like a Megasquirt or AEM, is extremely customizable and will let you to dial in the injector response of your turbo Neon much more precisely than a rising rate FPR.
Injectors are another important part of a turbocharged Dodge SX fuel system. Stock 2.0L Neon injectors will operate to some extent in typical, low-boost settings. According to most turbo Neon aficionados, the factory injectors can withstand up to 8psi of boost. As previously stated, that is also the maximum of the basic 2.0L internals. However, if you intend to build a more extreme turbo Neon, you will require larger injectors. The 577cc injectors found in the SRT-4 are the most frequent injector upgrade for turbo 2.0L Neons. You’ll need an aftermarket fuel management system or a rising rate fuel pressure regulator if you decide to upgrade your injectors.
Dodge SX Broadband
You’ll need a way to measure the air/fuel ratio if you have a turbo Neon setup with a rising rate fuel pressure regulator, spool boy mod, and updated injectors. This is where a wideband O2 gauge comes into play. Without some form of analog or digital readout, there’s no way to know air/fuel levels with the configuration described above. This problem is solved by using a wideband O2 sensor.
In comparison to a stock O2 sensor, wideband O2 sensors can measure air/fuel ratio over a much wider range. A wideband sensor can read between 5:1 and 22:1 in comparison to the stock narrowband sensor, which can measure between 14.5:1 and 15.0:1. This range is essential when modifying the fuelling parameters considerably.
Oiling a Dodge Neon Turbo
The 2.0L Neon, like most factory N/A engines that are turbocharged after the fact, must be properly adapted to provide oil to the new turbocharger. The most typical approach is to T off the oil pressure sender with a metal T-fitting. This retains the OEM sending unit while also providing an additional source of oil for the turbo.
You’ll also need to modify your Neon’s oil pan to accommodate the oil return line. To allow oil to be recirculated into the system, locate correct fittings and tap the oil pan. The tapped oil return line fitting must have a large enough diameter to accommodate the oil flow. If the fitting is too small, oil may flow out of the turbo and into the exhaust.
If you’ve heard of turbo systems, you’ve almost likely heard about intercoolers and what they do. Because the 2.0L Neon is naturally aspirated from the factory, an intercooler will be required to keep the air entering the turbo cool. An intercooler is included in the majority of pre-built Dodge Neon turbo kits. If you’re sourcing the components yourself, look for ones with good build quality.
In the case of 2.0L Neon turbo kits, a modest front mount intercooler with 2.5″ pipes is frequently included. To fit inside the limits of the Neon’s core supports and surrounding bodywork, the intercooler face must be rather small. Because the 2.0L Neon is naturally aspirated from the factory, there are no provisions for a massive FMIC.
While most people believe that a blow off valve serves only to make cool noises, it actually plays an important role in managing pressure within a Neon’s turbo system. A blow off valve, in simple words, is responsible for releasing excess pressure within a turbo system when the throttle plate closes. Blow off valves release this pressure into the atmosphere, resulting in the distinctive fluttering sounds. Check out our guide on blow off valves for more information.
If the pressure within your Neon’s turbo system cannot escape, the compressed air may go back through the turbo in the wrong direction, potentially damaging or destroying the compressor wheel. Installing a blow off valve eliminates the possibility of compressor surge and extends the life of your turbo.
Turbo Kits for the 2.0L Dodge Neon
With all of the above factors in mind, there is always the option of purchasing a pre-assembled turbo kit. While some Neon owners prefer to buy parts individually, a turbo kit is the most convenient way to ensure that you have all of the necessary turbo components in one place.
When acquiring a Dodge Neon Turbo kit, there are a few important compatibility and performance-related issues to consider. For example, ensure that the kit you order is compatible with the camshaft configuration of your 2.0L Neon. Turbo kits designed for DOHC 2.0L Neons will not fit SOHC vehicles, and vice versa. You should also consider the size and construction of the turbo provided in the package.
SOHC MMI Speed Shop 420a Turbo Kit
T3/T4 Hybrid turbocharger with 0.57 trim compressor wheel
There is no denying that the MMI Speed Shop 2.0L SOHC Neon turbo kit is an excellent value at under $850. The MMI kit is intended for all Dodge, Plymouth, and Chrysler vehicles with 2.0L 4-cylinder engines, including the Neon. Despite its high price, the kit includes everything you need to get started.
The incorporation of a T3/T4 hybrid turbo is one of the MMI Speed Shop Kit’s notable features. The T3/T4 combines a smaller T3 turbo’s exhaust housing with a larger T4 turbo’s compressor housing. As a result, the turbo delivers the airflow of a larger turbo but without the latency. It is an excellent system for the Neon, which requires immediate throttle response.
Furthermore, the MMI Dodge Neon Turbo Kit includes a high-quality 321 stainless steel turbo manifold. It is ported and polished, and it can handle up to 25psi of boost. A front mount intercooler is also included with the kit, however it may need to be somewhat adjusted to work with the 2.0L Neon.
Overall, don’t expect the MMI Neon Turbo Kit to be the best of the best when it comes to turbo kits. The price indicates that this kit is intended to be a low-cost choice. Having said that, it will most likely suit individuals looking to run a modest 8psi setup without going too much beyond that.
Related : Mazda RX-7 vs Toyota Supra
DOHC RX Street Demon Turbo Kit
T3/T4 Hybrid turbocharger with 0.57 trim compressor wheel
To be honest, the market for Dodge Neon turbo kits appears to be somewhat limited these days. At the moment, there are just eBay turbo kit possibilities for both the SOHC and DOHC 2.0L Neons. In the past, there were several really good solutions for both, but they have since been withdrawn. Having said that, keep that in mind while ordering this kit. While it is likely to perform well in low-boost applications, it may be a liability in high-horsepower applications.
The RX Street Demon kit for the DOHC 2.0L Neon is simply a revised version of the SOHC kit previously mentioned. That isn’t necessarily a bad thing because both kits have some redeeming features. The T3/T4 turbo in both is a solid option since it combines power potential with rapid responsiveness. This kit also includes a 321 stainless steel turbo manifold, which appears to be of high quality.
The DOHC RX Neon Turbo kit has several extra goodies that the SOHC kit does not, which justifies the higher price tag. For example, the Street Demon kit includes a manual boost controller kit that allows you to alter boost levels on the fly. An oil catch can, electronic turbo timer, and battery relocation equipment are also included.
Summary of the Dodge Neon Turbo Upgrade Guide
Despite being designed for a more civilian audience, the 2.0L Dodge Neon has taken the aftermarket community by storm. While the 2.0L Dodge engine isn’t the most powerful in the world, with forced induction, it has the potential to be quick.
The Dodge Neon was available with a SOHC or DOHC 2.0L engine. While the first generation was available in either configuration, the second generation was only available with the SOHC 2.0L engine. While the DOHC engine is better for boost, a SOHC Neon can be modified with a DOHC cylinder head. Because of the low compression ratio, this is the best overall arrangement.
In general, there are two approaches to turbocharging a 2.0L Neon. The first option is to build your own turbo system by collecting individual components. The second option is to just purchase a Dodge Neon Turbo kit. While the former requires more time and research, it is likely to be the more reliable option. There is a lot that goes into a 2.0L Neon turbo build, and the many engine management, fuel system, and supporting improvements required can be overwhelming. Fortunately, the Neon has been around for a long time and has a large and helpful aftermarket community.
While this article is lengthy, it only scratches the surface of what it takes to put together a quality Neon Turbo build.