"Tuning" in FH

I have to say that the lack of some sort of tuning was a little disappointing for me being a tuner in FM4, but after playing with the upgrades last night, they are NOT just direct carryovers from FM4. There seems to be a science on how to perform the upgrades, and a one or two specific classes that a car will perform really well... I realized that I only had a few cars upgraded to top-of-class across all classes. Since I had over 1 million CR after the lobby last night, I figured it was time to do some upgrading and shopping...

Power to weight is KING in Horizon... There is going to be an optimal build for the optimal class for a car. If you have to put every upgrade on a car to get it to top-of-class, it's probably going to be beaten by cars that have plenty of parts on the shelf. Now... this is all me speculating right now, but from what I've seen it's holding true...

Let's review some parts that seem to be surrounded by controversy on the FM forums...

• Race Transmission: There are those that are saying it's a useless upgrade. From what I've tested, it's a kick-ass upgrade that modifies the shift points and final drive ratios for optimal power. The cars pull harder in all the gears especially in the top gears. The increase in Shift speed is also a huge benefit here. The only downside that I've seen is in AWD car's launch. The cars seem to bog down on launch. Without the ability to adjust first gear or the final drive, there is no way to eliminate this drawback like in FM4.
  
• Upgraded Limited Slip Differential: These upgrades add weight and are not adjustable; however, my testing actually shows increased on and off throttle performance especially in higher HP cars. Test and see what it does for you! If you are having issues with stability when you get off the throttle, straight-line acceleration in lower gears, and/or issues with throttle oversteer in corners, try the 1.5-way to 2-way diffs..
  
• Race Brakes and Suspension (and tires): OK.. So here is where the lack of tuning hurts the most. Suspension and Braking can make a LB car out of a lemon, but we don't have that option here. I really like using the Sport suspension and brakes in my lower class cars (C, B, and some A). It seems to watch the power and handling requirements. I'm also matching the tires to the suspension types. If I'm using a stock/street suspension (some cars go from stock to street, and some go from stock to sport, which means the stock suspension is actually street) I make sure that I'm using Street tires. If I change to sport suspension, I switch the tires as well... Same goes for race... What I've found with the different suspensions is increased spring and damper performance as you move up... Much less bounce and much better control in corners, under braking and under power. I've also noticed much faster transition times. No real drawbacks other than not being able to tune. I highly reccomend Race Suspension bits starting with heavily upgraded cars in A-class, a good chunk of S-class and pretty much mandatory in the R classes.
  
• Engine Parts: Start with all of the parts that DECREASE weight. Exhaust, Throttle Intake (on NA), Air Intake, Valves, Pistons and Flywheel. Then move on to parts that do not ADD weight. Ignition, Fuel System, Carb (up to sport), Cams, and Displacement. Use Turbo/SC, Intercooler and/or Engine cooling last or to achieve a specific PI.
  
• Forza Race Aero parts: Since precise handling and clean laps are not nearly as important in FH as they are in FM4, I'm finding that they have more drawbacks than benefits in the lobby/open world events. I can see using the race aero parts if you are building a serious Circuit/P2P/Street Racer or even for a specific challenge (like the 180 MPH dam free roam lobby challenge), but as a "lobby" tune or single player car, race aero, with it's reduction in Top End and acceleration (in lower HP instances) hurts more than it helps! This is especially true since you cannot adjust the downforce and are locked in to the system's setting. I'm finding that I'm putting Street and Sport body parts on or just sticking with stock...
  
• Roll Cage and Weight reduction: Be careful with both of these. I've been sticking with doing sport weight reduction on most of my cars so far and only street or sport roll cage. You can actually achieve a better Power:weight ratio without doing the full weight reduction. The weight PI (handling/braking) that's added with the race roll cage is offset with a reduction in Launch and acceleration. Since handling and braking are not nearly as critical in FH as they are in FM4, I suggest skipping or using for the same reasons listed for the Race Aero parts...

Hopefully this helps everyone get started with building their cars in FH. I will be working on a Power to weight calc for those that are serious about finding the BEST parts combos and recording them...

Cheers!

Thanks for the tips lou!

Yeah, this is an AWESOME write up! I find the nitty-gritty details of tuning interesting, but overwhelming. I appreciate you sharing your findings like this.

Have you noticed if road surfaces have an impact on tire choice? Eg, do "race" tire compositions help on gravel and dirt the same way they do on the roads?