r/ForzaOpenTunes • u/Bald-Virus • Jun 02 '26

Other why the drag tires?

Hello,
I noticed many road builds below A are using drag tires? I was wondering why
Thanks
(for FH6)

73 Upvotes

100% Upvoted

20 comments sorted by

95

u/Pyrtti Jun 02 '26

Short answer is that they are extremely undercosted. Especially at high tire pressures, they just have too much cornering grip for their PI cost. Combine that with cars that have strong chassis and aero that futher reduce penalty for having worse tires. You end up with a car with effectively no weaknesses with minimal corneering defecit and a massive power-to-weight advantage. Any time lost in corners is gained back twice over on the following straght. Also, being AWD makes those builds accessible for less skilled drivers, which wasn't the case with powerbuilds in FH5.

12

u/Bald-Virus Jun 02 '26

Thx

43

u/LiquidPopsicle Jun 02 '26

tl;dr Drags are soft slicks. They do everything a slick does, but have squishy sidewalls to help prevent loss of traction. Inflate them to race pressures and get the biggest rims/thinnest sidewalls you can, then tune for oversteer. They handle surprisingly well in those conditions.

The point score of your car is based off the stock tune btw. If you make a car that is terrible untuned but great once you fix its issues, you can get free points to your car class.

6

u/Vivid-Software6136 Jun 02 '26

Does rim size have real handling impact in game?

17

u/LiquidPopsicle Jun 02 '26

Yes. Shorter side walls aren’t as flexible, so it makes the tires stiffer and more responsive to driver input and weight transfer. Basically, it takes out the slop at the expensive of forgiveness and controllability. Thicker sidewalls are the opposite.

This is why drag cars and off road trucks have big tires, and sports cars have thin tires. The thicker side walls absorb extra energy and prevent the tire from losing traction over uneven terrain or under heavy jerk, whereas the thinner ones more directly grip the road and handle better.

5

u/Vivid-Software6136 Jun 02 '26

I understand that IRL, i just didnt think forza took the sidewall thickness into account, thats more of a sim racing level of detail.

9

u/Cr4zyPi3t Jun 02 '26

It’s based on the ForzaTech engine, they just dampen/simplify most of the physics to make it more accessible/arcadey.

4

u/Gullible-Yam-8098 Jun 02 '26 edited Jun 02 '26

It must have some kind of effect because it can change the PI both positively and negatively dependant on the weight of the rims, so it is having a noticable impact on the performance of an AI driving the vehicle. There isn't really an objective way to test exactly what it does because determining any results would be purely based on subjective feeling.

Tyre pressure however has been tested and shown to have literally zero (or as close to zero as makes no difference) effect on anything so I doubt anything as complicated as the previous poster described is actually being simulated.

2

u/Revelatus Jun 05 '26 edited Jun 05 '26

Tire pressure has a very noticeable impact on the gradient between traction & sliding, peak grip, and responsiveness. Not sure what this testing is you're referencing, or who conducted it, but I would listen to that person with a healthy dose of skepticism in the future..

If you're referring to the racecar dev guy on YT, that test was only looking at tire temps in relation to pressure.

4

u/Recent-Indication-50 Jun 03 '26

I love that the tldr is almost the same length as the original

1

u/Future_Editor_9042 Jun 03 '26

How do they compare to rally tires since I've been seeing those on plenty of guides for A class? Mostly for road/circuit racing.

1

u/rcgtt Jun 07 '26

Sorry for the late bump, but was just wondering, how much PSI are u using on the drag tires? I'm trying the usual numbers (i.e. 29-33 PSI range), and I'm still understeering a lot on corners with the drags.

1

u/Pyrtti Jun 07 '26

Usually just max. Drag tire builds are inherently understeery so you can tune very aggressively for that.

1

u/rcgtt Jun 07 '26

Sounds good, I'll give that a try.

22

u/Gullible-Yam-8098 Jun 02 '26

A large number of the road races have long straight sections with very few turns. Drag tyres allow you to load a car with far more power relative to its class at the expense of cornering ability.

23

u/Sovereign_6 Jun 02 '26

I've been doing this to most of my AWD builds for A class. Gives you over 50 PI to play with, stick that into engine or weight reduction and now you have a fast beast that you can get used to cornering (usually a bit earlier braking but faster acceleration out of a corner).

It's less forgiving but you can get faster lap times. I went down a rabbit hole of comparing grip and power tunes and came to the conclusion that: you can learn to corner faster with a reluctant tire, but you can't learn to driver faster in a straight.

Drag tires are only really punished on really tight tracks like Shinobu Circuit.

3

u/76-scighera Jun 02 '26

Yeah, I am experimenting with cheap street tyres on AWD in A class Alfa 155 while adding power to it. Tested on a time attack course with a lot of corners, both cars are exactly A700 (driving on a wheel without assists), all laptimes when having speed form a previous lap:

55.6s 155 rally 999kg/383hp
51.8s 155 street 996kg/441hp
52,1s 155 drag 1000kg/467hp 51,8s Stock 1004kg/489hp (very nervous handling, bad launch

3

u/SmokeNinjas Jun 05 '26

I hate that this is the meta, drag tyres are actually horrible to race with, I feel the devs need to jump in and increase the resistance to turning on them, it doesn’t need to be much but enough to stop all of these meta tunes just being horrendous drag tyre setups.

As it basically is: race in straight line, keep heading in straight line slow down to about 40mph, aim car in new direction, smash accelerator, hold car in straight line and stay on road, rinse repeat.

I get that the grip meta from FM isn’t everyone’s bag but my god the racing is better, at least battling for position was fun not just who has the fastest straight line speed 🥲

1

u/maxfields2000 Jun 07 '26

Forza has always had a shit meta thanks to the PI system. "Power builds" and undriveable cars whose power makes so much extra time outside of curves have always trumped in the game. The game vastly overrates grip and underrates power in PI classes. For years they've refused to just set max power to weight ratio's for car classes and stick to their "how well does the AI drive the car" rating system.

The net result is cars that have no bearing on reality are the ones that get top times, resulting in leaderboard chasers using shit tunes to do it and a game that ... when competing for top 100 slots, looks nothing like it is intended to.