Just a simle question about tuning, for the sake of discussion

This will sound probably dumb and maybe obvious but I thought I’d throw it out there. Wouldn’t the very first thing you do to get a car to handle better be getting better tires for it? Or maybe that just depends on the car.

And also, if you want to stay in the same class, it seems like tires bump you up quite a bit. I was wanting to do this with my Ferrari 68 GTB/4 and upgrading the tires to even just the first upgrade bumps from C to B. I wanted to stay in C with it. Grrr…

Yes it does depend on the car if you are trying to stay within its class, the 365 is really close to B class to start with. I would put race springs and arbs on it first then maybe go with tire width or street cage if I had any PI left, not much to work with on it when trying to keep it in C class you might need to bump it up to B.

Also Thanks for trying my RS1800 glad to hear you liked it

You’re probably getting me mixed up with someone else, or I said something that was misleading. I don’t even have the xbox live set up yet, so I don’t think I could’ve tried that car. I did say I love the way it looks I think. I think those are cool cars.

I’m thinking that Ferrari might be a good B class candidate for me. Maybe. I tried upgrading the roll bars but I’m not sure I like it now. I didn’t do the racing ones though. But that’s why I was thinking tires might help more. But yeah, they bump it up a class I think. I also think the brakes could be better. But that’s just how I’m driving so far. It’s because I don’t know the tracks well enough to always know how much room I have to slow down after a good straight. I do well at using different pressure and not always standing on the brakes full, but sometimes I feel like I need more brake with that car. I suppose it’s from being a novice. Plus, I always thought the real racers go as fast as they can all the way up to the last point and then really get on the brakes hard before turning.

It depends on the car. Obviously tires are the most foolproof way to drastically improve your handling / braking and whatnot, but you’re right about the PI. I would probably go with sport tires and racing roll bars and diff for that particular car. But if you’re going to be zipping around in say, a Ford Ka, you simply do not need the upgraded tires because the lack of high speed maneuvers and hard cornering. If you have it floored and you’re not drifting to the outer apex of the turn, your tires are better than you need. Which means the points for that PI can be spent elsewhere instead.

-snip-

Whoops, sorry didn’t, read the last part of your post. I see your dilemma. Unfortunately for this car you can not upgrade the tires and keep it in C class. In this situation, what I would do:
First create some leeway with the pi:
-Heaviest rims (DUB, Lowenharts, whatever)
-17" front and back.
-Forza front bumper and spoiler.
-Also, I’d suggest making use of the aspiration glitch: buy a turbo or supercharger. Go into your engine upgrades, upgrade the turbo/supercharger. Then immediately sell whatever upgrade you just purchased. This removes the aspiration. The intercooler will remain available despite no aspiration. Upgrading the intercooler gives you dead weight, and brings your pi down.
-Race differential.
All of this brings you down to 403. From here what I would do is:
-Sport transmission
-sport brakes
-race springs
-race rollbars
-Race body reinforce/cage
-1st front tire upgrade
-street flywheel
-sport driveline.
This is almost entirely focused on compensating for the stock tires. Brings you to a perfect C425

-snip-

Oh and here’s a very rough base tune to go with that, gets ~2:15 on Catalunya GP
Tires: Front -28 Rear -27
Gears: 4:30
Allignment: Camber front/rear: -0.8
Toe front: 0.8
Toe rear: -0.8
Caster: 6.4
Roll bars: Front: 36, Rear: 5.50
Springs: Front ~1300 Rear ~1200
Height: F/R: 6
Damping: Rebound: F/R ~ 10
Bump: F/R ~ 8
Aero: F: ~90, R: ~180
Diff: Accel: 15
Decel: 85

See if that helps any.

Wow, nice tune. I might have to try all that. I don’t really understand how you can get rid of “aspiration”. And why you would do that. I take it you are trying to downgrade the level to give more leeway for other parts. ??? OK, that’s what it appears to be.

Out of curiosity, why heavy rims? Wouldn’t the stock ones be heavy too?

Thank you for the tips on the build and tune. I’m blown away by all of it. The camber seems like a lot and the toe in and out seem like a lot too. But I’ve yet to tune a car. Plus I’m guessing that’s because Catalunya is a very tight course. But there’s that one long straight. LOL.

Heavy wheels because weight effects your PI, as does anything that has a drastic negative effect on any of the categorized ratings (the adjustable front and rear ground effects from Forza that are available on nearly every car). So if you pick something like the car you’ve mentioned or the Audi TT. If you’re trying to stay in the C-Class you’ll need to lower the PI if you add any upgrades.

As far as upgrades, at least one other freebie are typically the sway bars and the differential. I don’t recall ever seeing much of a PI change when adding sway bars (folks can correct me if I’m wrong). Maybe that indicates that T10 didn’t think sway bars effect all that much, shrug. The differential(race) cancels any increase in PI with the additional weight that it adds.

Last thing I’ll mention, your tire pressure is one of the most effective things to change for a decent benefit. Yeah, there are always this piece for that car, or this for that… but you can always adjust tire pressure. In lobbies, autovista, rivals, quick races… every race you ever have. Get to where you understand how PSI effects your driving and you’ll have good start to being generally competitive.

OK, that all makes sense about the weight thing. I’m starting to understand that now as I build some other cars. I have left some with stock rims because a set of rims might have bumped them up to a higher class.

I’ve yet to do a differential, so I should. I’m not quite sure I’ll understand how to utilize it. I understand a different gear ratio will yield different results as far as the wheel spin rate or whatever. I remember in my younger days the drag racers wanted lower gears. Like 4:11’s. But I don’t know if it was because it allowed them to have more grip at the start, meaning more rpms per turn of the rear wheel, or if it gave them a better final drive gear that would make them faster. I’m thinking it’s the former.

Because I do notice some of the race cars in real life, like when they start off in the pits a LeMans, it sounds like they’re starting in 2nd or 3rd gear the RPM’s drop so low. So I’m assuming the gearbox has taller gears that allow them higher speeds in the straights, and well higher speeds over all. But I’m not sure how the rear gears fall. I guess I need to read up on this. Any place to learn about this better?

I have no clue what to do about tire pressure at all. Where can I learn about that? I’m completely lost. I did finally learn how to pull up telemetry, but I was driving so I didn’t really look at it well. LOL. Does the telemetry show tire temp or something?

One more thing too.

I don’t know if I’m going crazy or not, but it seems like I’ve bought some racing springs for a couple of cars lately and as soon as I go into tune them, they already have some camber set on them. I’m pretty sure it wasn’t me. And I’m pretty sure I found two cars to have -.5 camber on both front and rear, which I thought sounded like a lot. I think it was the 2000 Ford Mustang Cobra. And one other one, but I don’t remember.

Is that possible? And is that supposedly how it would’ve been set up from the factory or in stock form? I assumed they all were just zeroed out, as so many others have been.

Either that or I’m going crazy.

All cars, when upgraded with race suspension, will have the default set up of -0.5 camber and 5.0 caster… I think.

after buying upgrades there will some default tune on them. -0.5 camber is pretty mild camber and can be found even on some passenger/non-race cars. Depending on the race camber CAN get into the -3 to -4 range, and that is pretty extreme.

This link (https://files.nyu.edu/dwc255/public/forzaupgradeandtuning.html) is a document that takes a good look at tuning your PSI. What I like about it so much is that you can take it in stages. Initially, you’ll focus on just the general temperature of the tire. Then as you start homing in on the right temperature, you’ll then start needing to tune your suspension to account for some oddities in how the tires are heating up. Next thing you’ll know, you’ll be hip deep in suspension tuning theory. That’s where I’m at and I’m trying to get a grasp on it.

Here’s a “cliff notes” version of the link above…

Lower Psi = Higher Temp … and the opposite Higher PSI = lower temps

Regarding telemetry and trying to watch it. One things that’s required is the ability to watch replays, and that means you must have an internal harddrive. IF that’s not an optino for some reason, the best thing I could suggest is racing a familiar track with your transmission set to automatic. Yes, it won’t allow for the highest level of performance, but for me at least it’s the one thing I find starts going wrong if I’m trying to take a glance at what my camber is doing in the middle of a turn. IF replays are an option then here is what we do. Go to Free Play in the main FM4 menu and select hot lap. You’ll first select your car. If you scroll to your left you’ll have your garage available, from here you can select any of your OWN cars. Pick the one that strikes your fancy, then you’ll have your choice of which environment to race (Bernese Alps, Camino Viejo, etc). Next you’ll have your choice of which specific track you want to race on. Typically the longer “full” tracks are to the far left, moving next to the shorter “club” versions of that track, then the reverse versions of all of those. In some cases, (like Nurburing and Fuji) you have the choice of segments of the course. These are the longest two courses in the game. In other cases, like Sedona and Benchmark(DLC), there will be options for oval racing and drag strip. Pick the track that you want to race/tune on.

There are preferences for which tracks are better to test on, some are better examples of speed over handling, while others have a personality that is completely unique to the others.

Run 3-4 laps and then quit, but don’t continue just yet. It’s at this point that a host of valuable information is available. Firstly, the leaderboard. When you select the leaderboard it will show you your ranking among all those who have ever raced (while connected to xbox live) that specific track with the specific class of car you’re using. I aim to be in the top 1% of drivers, however, the best I’ve ever done was in the top 2500 times… it’d be amazing if they’d do fractional percentages. Backing out of that, you have options to save or watch your replay. Select view replay, and turn on your telemetry, hit your right bumper 5 times. You’re looking at the Heat pages. Each corner relates to it’s relative corner of your car. I like to switch to the Far game camera view as it makes recognizing the associated corner instinctual. Do this by selecting the camera icon at the bottom right of your screen, press “a” and select left or right for the view you like.

If you’re watching for temperature, you don’t necessarily need to watch the full replay. Using the controls at the bottom you can rewind, fast forward and pause your replay. Unfortunately, this isn’t like the FF or RWD available while watching netflix, it just moves in 20 second increments. The temperature you’re interested is later in your laps, 3rd or 4th.

Hopefully, this’ll help you find what you’re looking for.

Wow, I’m learning so much!!!

OK, I figured out today how to look at telemetry while I’m driving. Which is kind of a pain. I didn’t realize you can do a replay and watch telemetry during. That is SWEEEEEEEEEEEEET!!! I’ll have to try that. And yeah, we have the 250 gig xbox so I can record. I just recorded a lap I did. However, I have done quite a few hotlaps and it says it records the time but I have no clue where to find those times after the fact.

As for the tires, it just dawned on me that if you choose to put on racing tires on your car, they may need to be hotter than a normal tire to perform well. Is that true??? I think that might be true in real life and I think I might need to scale back a few of my cars for tires. Or learn how to adjust temps better. I’ll have to look at that.

So… thank you for helping me. This is fun. I still would like to get a better handle on how to tune gears. The differential AND gearbox. For example, I kind of like the GMC truck thingy but the gears are just all wrong for just about any track I’ve tried it on. 1st and 2nd are OK and then third is like way too high. RPMS are too low and it sort of poops out when you shift into third. Would be nice to adjust. I don’t own that car but you get the picture. And then there’s that whole rear end gear thingy. I should’ve said earlier the draggers like “higher” gears. Not low. But I think low because I think the higher gears mean more revs per turn of the wheel. I think. Or maybe not. I thought that allows them to put more torque down and slip less. But seems kind of backwards.

As far as I understand, the recommended temperature is relevant for the race tires. There are different compounds of racing tires and conceptually you’re correct. In the real world, economy to all season radials are typically designed for endurance/longevity with some general consideration for handling rain and snow. The operating temp of these tires is relatively low, they are not meant to be “warmed” up or used hard enough for their operating temperature to mean anything. This is why when the idiot boy racer does a lengthy burn out in the school parking lot, what will left is a chalky powder. There was no benefit of traction from this heating up of the tire.

Now I imagine the sport tires (one level less than the race tires) to be more of a “rain” tire. With that in mind, I would take the recommendation of 180-210 to be directly relevant to race tires. For tires less than race, you may try to keep the temps closer to 180-190. But I’d be surprised if T10 got that specific with that part of tire physics.

I haven’t done any endurance racing in FM4, but when I was racing Gran Turismo 3, the standard tires lasted much longer than race tires. Maybe someone else could chime in on that.

I can’t comment much on transmission tuning. I use a tuning spreadsheet that does its own math. However, I will share that I’ve had great success by upgrading to only the sport transmission so that I could adjust the final drive ratio. In some cases, the specific gears were still funky, but good performance was found by working with the final drive setting. If you watch the individual performance categories, you’ll notice that “launch” often takes a big hit when the race transmission is added. My experience with racing in the lobbies is that the launch is EVERYTHING. Yeah, you have to be able to STAY out front, but getting out in front seriously helps to avoid yahoo’s who can’t keep their cars from “kissing” others.

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Oh thank you for that wisdom. I didn’t know what the difference is in trannys. Other than that the Race one allows you to adjust gears and is a 6 speed. And I do see that shift times are changed with each tranny. I think it’s in green letters at the bottom.

So much to learn.

I do wonder if race tires are overkill on some of the slower cars. I really like the 87 Ford Sierra and I have built it up to B class. But I think it needs a little more power and I might have to scale back on some of the level of tire I have to see if I can add some power and stay in B class. I’ve yet to be real competitive against the game in S class. And A class is still hairy. Actually, I just finished up my season of Masters and I got 1st place in the championship but I only placed second in each race. I took a corner a bit too fast in both races and ended up a bit off course and was overtaken. Grrrrrrrr… But I felt like the car handles really really well but could use more power. I might have overkill on the tires. I have race tires and I even had them widened.

I’ll tell you another thing, I have no clue how to start a race without spinning the tires too much. Usually when I try to keep the RPM’s lower, it almost sort of stalls for a second. And if the RPM’s are too high, I just burn too much rubber. Maybe I need to start another thread, but is there any trick to getting grip sooner than later? You just have to figure out what RPM for that particular car and set up?