Forza 7 Build Guide
Part 2 - General Building
This part explains how to build cars in a way that they will work good on most tracks.
Understanding Classes and Divisions
When building cars for general use most of the time you will want to build the car for a certain class or division.
When building for classes the most important car stat is the handling stat as it determines if you're building the car towards grip or speed. The following list provides the base handling as an orientation for each car class:
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E300: 4.0
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D400: 4.5
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C500: 5.0
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B600: 5.5
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A700: 6.0
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S800: 6.5
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R900: 7.0
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P998: 7.5
Cars with a handling stat below the base handling are more speed oriented, cars with a higher handling stat are more grip oriented.
For divisions it's mainly the same since each division also has a class assigned albeit sometimes with a lower maximum allowed PI as the car class would allow. If the divisions maximum PI differs significantly from the car class maximum PI you may simply reduce the base handling accordingly.
Step 1 - Setting Your Target Handling
Start the car building by deciding for which class or division and what handling you want to shoot for. Use the above base handling list as an orientation.
A target handling below the provided base handling means you build more for grip, a target handling higher than the provided base handling means you build more towards grip.
Keep in mind that you shouldn't strive too much from the base handling otherwise you will get a car that performs only good on high speed or high grip tracks.
As a general rule of thumb don't go more than 0.3 below or above the base handling if you want the car to perform reasonably well on most tracks. This becomes more important on higher car classes.
Step 2 - Base Handling Upgrades
Start by installing base handling upgrades to achieve your target handling.
Platform and Handling
First install base platform and handling upgrades:
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Race brakes
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Race suspension
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Race anti-roll bars
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Race weight reduction
Note that while race weight reduction is benefical on most builds, for very light cars (<2300lb) street or sport weight reduction may work good as well.
Drivetrain
Next install the adjustable race differential as it costs no PI and is always beneficial:
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Race differential
Aero and Apperance
Next install adjustable front and rear race aero kits as this beneficial on most tracks:
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Race front bumper
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Race rear wing
Tires and Rims
Now have a look at your handling stat, if it is still below your target handling install tire upgrades. Upgrade tire compound and tire width to barely hit your target handling.
Tire Compound
First upgrade tire compound if your handling is significantly lower than your target handling then proceed with upgrading tire width to fine tune handling to the required target handling.
Tire Width
Upgrade tire width starting with upgrading tire width of the driven wheels (rear wheels for RWD/AWD, front wheels for FWD) before non-driven wheels to barely hit your target handling.
On FWD cars upgrading tire width of rear wheels can also be used to lower PI while increasing handling at the same time.
Note that since tire width upgrades should match the cars power for best handling as described in Part 1, upgrading tire width that doesn't follow these rules will create balance issues that need to be addresses when tuning the car.
To learn more about balance issues and how they can be remedied have a look at my Forza 7 Tuning Guide - Part 5 Balance and Stiffness Tuning,
Step 3 - Upgrading Power
With the target handling being set we can now focus on upgrading power.
Conversions
Engine
First you need to check whether an engine swap is necessary to hit the PI limit. This mainly depends on how much PI is left after performing the target handling upgrades. If there is a lot room left especially if the car is still one more classes below your target PI an engine swap is probably required in order to hit your target PI.
Forced Induction
If you settled for the engine (either stock or swapped engine) you should check if forced induction upgrades make sense. This depends on your PI budget left and depending if your'e going for a more grip or speed oriented build.
For more speed oriented builds if you have still a lot of PI budget Turbos or Twin Turbos can make sense. They will add a lot of power and provide you with additional sport and race forced induction upgrades in the engine upgrades.
For more grip oriented builds if you have still a lot of PI budget Centrifugal Supercharger or Positive Displacement Supercharger can make sense. Generally Centrifugal Supercharger should be preferred over Positive Displacement Supercharger as it usually offers a better power / weight ratio. As with the turbos installing supercharges will also provide you with additional sport and race forced induction upgrades in the engine upgrades.
After settling with engine and forced induction install engine upgrades to roughly hit the target PI.
Generally upgrading power is an iterative process where you may want to jump between different engine configuration to see from which combination you get the most out of in terms of power and weight. For more speed oriented builds you may want to put more emphasis on overall power while for more grip oriented builds you should strive for the best power to weight ratio.
As in Part 1 explained you need to do engine upgrades backwards to avoid handling issues.
Engine Output
First start with upgrading the engine output component which is the Exhaust as this opens up the possibility to install further engine upgrades without introducing handling issues. Before upgrading make sure to check out which stock exhaust is installed. On some cars this might be a Street exhaust (only Sport or Race upgrades available) or Sport exhaust (only Race upgrade is available). If there are no exhaust upgrades available the car is already equipped with a race exhaust.
The higher you upgrade the exhaust the more upgrade options you will have for the core and input components. Unfortunately the race exhaust upgrade is also one of the most expensive engine upgrade in terms of PI because it offers both considerable power increases in combination with high weight reduction so you need to carefully balance exhaust upgrades against other engine upgrades.
Forced Induction
After upgrading the exhaust you may check if upgrading forced induction components make sense, which can be either a Turbo, Twin Turbo, Positive Displacement Supercharger or Centrifugal Supercharger depending what forced induction conversion you went for or if the car has a stock turbo or supercharger equipped.
Upgrading forced induction is usually only viable if you have a considerable PI budget left as these upgrades usually cost a lot of PI. Make sure to upgrade forced induction not higher than exhaust to avoid handling issues. As already stated turbos change the build towards a more speed oriented build while superchargers towards a more grip oriented build.
You may jump between engine configurations with and without forced induction upgrades to see what fits your PI budget best. Usually the highest power increases can only be achieved when using forced induction upgrades.
Engine Core
If you settled for forced induction upgrades you can now upgrade the engine core components which are Pistons, Displacement, Valves and Camshaft.
When you're going for a more speed oriented build prefer camshaft and displacement upgrades, for a more grip oriented build prefer pistons and valves. Again make sure not to upgrade core components higher than exhaust to avoid handling issues.
To maximize power output try to spend the PI budget completely for Exhaust, Forced Induction and Core Upgrades, only if it's not possible advance to engine input component upgrades.
Engine Input
If there is still PI budget left you can upgrade engine input components which are Air Filter, Intake Manifold, Fuel System or Carburetor and Ignition. Make sure to upgrade input components not higher than engine core and forced induction components to avoid handling issues.
When you're going for a more speed oriented build prefer fuel system, carburetor and ignition upgrades, for a more grip oriented build prefer air filter and intake manifold. Race fuel system or carburetor are very good speed upgrades as they offer the highest power increases of the input components. Likewise race intake manifold is a very good grip update as it usually offers the biggest weight reduction of all input components.
Engine Cooling
Finally after performing all engine upgrades check whether the cars power has exceed 400hp or more. In this case engine cooling upgrades Oil and Cooling and Intercooler are required to match engine power and avoid handling issues. Note that the intercooler is only available when the car is equipped with forced induction.
As in Part 1 explained you need to install cooling upgrades in following cases:
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Street Oil and Cooling and Intercooler if car power >= 400hp
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Sport Oil and Cooling and Intercooler if car power >= 500hp
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Race Oil and Cooling and Intercooler if car power >= 600hp
Cooling upgrades usually don't come with high PI costs so most of the time you will not be forced to drastically change your engine upgrades but they will come with a weight increase which may cause to underrun your target handling.
Engine
Step 4 - Optimizing the Build
After you've settled with engine upgrades you now try to optimize the build in terms of handling and acceleration / speed. This may cause an PI budget overrun which may require to re-adjust engine upgrades. Sometimes even your target handling might be under- or overrun so you might even forced to go back to Step 2.
Platform and Handling
Chassis Reinforcement
Depending on the car type and car weight installing chassis reinforcement upgrade can be beneficial.
As in Part 1 explained upgrading chassis reinforcement in the following cases can be beneficial:
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Street chassis reinforcement: for trucks with 3500lb or more, for utility cars with 3000lb or more or for street cars with 2500lb or more weight
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Sport chassis reinforcement: for sports cars with 2000lb or more weight
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Race chassis reinforcement: for race cars and high performance cars with 1500lb or more weight
Also in some cases you may only reach or maintain your target handling without sacrificing too much power when installing street, sport or race chassis reinforcement.
Note that if chassis reinforcement doesn't match car type and weight stiffness issues are introduced that need to be addressed when tuning the car.
To learn more about stiffness issues and how they can be remedied have a look at my Forza 7 Tuning Guide - Part 5 Balance and Stiffness Tuning,
Drivetrain
Transmission
Depending on how much power has been added as compared to stock power upgrading the transmission can be beneficial.
As in Part 1 explained upgrading transmission in the following cases can be beneficial:
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Street transmission: if the power exceeds 200hp, also sometimes Street transmission actually lowers PI
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Sport transmission: if the power exceeds the cars stock power by more 100hp or more
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Race transmission: if the power exceeds the cars stock power by more 200hp or more
Aside from matching the transmission to power increases installing street, sport or race transmission can sometimes offer significantly higher acceleration and / or speed rating, Especially higher acceleration is beneficial on almost all tracks. Try to find the best balance between acceleration or speed gains and PI cost from upgrading transmission.
Installing sport and race transmission has most of the time a serious impact on PI so you will probably need to reduce engine upgrades to hit the PI limit again.
Note that if transmission doesn't match power upgrades balance issues are introduced that need to be addressed when tuning the car.
To learn more about balance issues and how they can be remedied have a look at my Forza 7 Tuning Guide - Part 5 Balance and Stiffness Tuning.
Tire and Rims
Rim Style
Selecting the right rims depending on car type, weight and build type can significantly improve the handling of the car. It can also quite dramatically impact PI especially when you choose lightest or heaviest rims.
Generally you should aim to match rims to car type and weight for best handling. Only if PI budget doesn't allow you should deviate from choosing matching rims.
As in Part 1 explained upgrade rim style according to following rules:
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Lightest rims for modern race and high performance cars
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Second lightest rims for early modern race and high performance cars and modern street or sports cars
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Third lightest rims for vintage race and high performance cars, early modern street or sports cars and modern utility cars
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Fourth lightest rims for early vintage race and high performance cars, vintage street or sports cars, early modern utility cars and modern trucks
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Fifth lightest rims (heaviest rims) in all other cases
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If the build uses speed any engine upgrades such as displacement one weight class lighter is required for best handling.
If rim weight class doesn't match car type and weight stiffness issues are created that need to be addressed when tuning the car.
To learn more about stiffness issues and how they can be remedied have a look at my Forza 7 Tuning Guide - Part 5 Balance and Stiffness Tuning,
Rim Size
Same goes for rim size, you should aim to match rim size to car weight for best handling unless your PI budget doesn't allow.
As in Part 1 - Forza Build Basics explained upgrade rim size according to following rules:
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for production cars one rim size upgrade front and rear is required for each 100lb over 2400lb, i.e. 2500-2599 first rim size upgrade, 2600-2600 second rim size upgrade etc.
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for race cars always use stock rims for best handling
If rim size class doesn't match car weight stiffness issues are created that need to be addressed when tuning the car.
To learn more about stiffness issues and how they can be remedied have a look at my Forza 7 Tuning Guide - Part 5 Balance and Stiffness Tuning,
Step 5 - Finalizing the Build
In the final phase you try to spend the last bit of PI budget.
Engine / Drivetrain
Flywheel, Clutch and Driveline
Driveline, Flywheel and Clutch upgrades can be used to spend the last bits of PI budget.
Start with driveline, flywheel then clutch. Upgrading the driveline usually cost less PI compared to flywheel or clutch. Upgrading flywheel and clutch becomes more important on high power cars.
If the flywheel doesn't match engine upgrades balance issues are introduced on the front of the car that need to be addressed when tuning the car.
Likewise if clutch or driveline don't match transmission balance issues are introduced on the front and the rear of the car that need to be addressed when tuning the car.
To learn more about balance issues and how they can be remedied have a look at my Forza 7 Tuning Guide - Part 5 Balance and Stiffness Tuning,
Aero and Appearance
Rear Bumper and Hood
Removing the rear bumper or upgrading the hood can be used to extract the last bits of PI budget. Not all cars however provide rear bumper or hood upgrades.