Maxwell's Speed Shop's xDeaDxZeppLiNx's Drag Tuning Walkthrough

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I thought I would post a walk through or a build journal so to speak for building and tuning a drag car. There isn’t much as far as a guide for drag specifically. Hopefully this will be helpful.

Before we get to far, there are alot of guys that are better at this than I am. I am very thankful to those that have shown me what I know and I am happy to pass on anything else I have learned along the way as well.

For this build I am going with S class. Keep in mind that when picking a car, the higher the stock PI, the less you’ll be able to do to it. In this walk through, I will be building a GMC Syclone. Should be an 8.4 second or so car when we’re done.

I have a couple paintjobs for it but I found one that I think is AWESOME by a guy named BONEHEADBLOKE, the file is “REV-IT’s Syclone”. Just a really clean, well done cool looking truck!!

Build-

  • 5.9 Ford racing engine
  • RWD drivetrain
  • NO Aero, rear aero can help grip on the launch but slows you down on the big end. I’m leaving it off this build.
  • Drag Tire compound, widest rear, drive tire 325/40R16
  • light rims, I use Alumistar 2.0 Drag. I increase front rim size because I think it looks cool. It can free up a PI point if needed too, maybe add a touch of weight up front but probably not significant. Not crazy huge, just a size or 2
  • Race clutch, trans, driveline and diff
  • Race brakes, springs, ARBs, weight and cage
  • Race restrictor plate

Ending with and S Class 744PI, 994 hp, 783 lbft, 2835 lbs and 55% front bias.

Tune-

To start off with, I was taught a very basic, can almost put on any front engine, RWD Drag car and have it work kind of tune. We will start with that. I’m sure someone has posted YouTube videos that have similar settings. I have a few little things that I have switched up from this basic tune for myself, but for now this is where we’ll start.

  • tires, 55 front and 32 rear
  • gears, we’ll get back to gears
  • camber, 7.0, 0.0 toe, 0.0, 0.0 caster, 7.0
  • ARBs 40.00, 40.00
  • springs, all the way down in front and all the way up in back, 146.8, 1174.8
  • ride height, all the way up both front and back, 6.9, 6.9
  • rebound, 1.0 front, 13.0 rear
  • bump, 13.0 front, 1.0 rear or leave at default. The bump rear is where the wheelie can be tuned out. Raise rear bump to lessen the wheelie
  • downforce no setting, lowest setting if used rear
  • braking, set to whatever you prefer
  • diff, 100% accel

Now the gearing. Gearing is where the biggest amount of time will be spent, searching for that perfect launch, or getting it to pull on the big end, etc. This is all going to be your decision or choice. For a first run, using a 5.9 Ford Racing engine, a very good, effective starting point for most cars is,
Final drive - 2.65
1st - 3.20
2nd - 2.10
3rd - 1.50
4th - 1.20
5th - 1.00
6th - .90

For the 1/4 at the Air Strip this will only use 3 gears, 5 if you run the mile. The mile is fun in this truck. Just starts floating towards the end.

Anyway, with this base tune and 3 runs on the Airstrip Test Track 1/4, I ran a best of 8.425, with that run having a huge 1st gear wheelie. If you can throttle control the launch, hold around 4-5000 RPM and ride the wheelie, it could be very fast.

Well, there is a basic, beginning build that can make some very fast cars. The same steps can be taken and plugged into almost any other RWD, front engine, typical drag car. I will add to this over the next few days as I go through fine tuning for launch, losing the wheelie and finding the gearing that feels the best for this build. Stay tuned!!

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Nice write up Zepp

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Thank you sir!! More to come soon!!

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Great job buddy!

PRKid
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See, now I’ve seen inside of the masters brain…good write up budd.

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Thanks guys, I do appreciate it! I’ll have some more up here maybe tonight or tomorrow. Dive into some gearing and suspension, see what we can do with it.

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Ok, gonna try to get this in during my break, lol. In between my jobs this morning I jumped on and messed with this truck. Here’s what I did, I will try to explain better later on when I have more time.

Tires are still 55 front, 31 rear

New gearing, there’s alot to explain later. I have a few different processes, lol.
Final - 3.90
1st - 2.05
2nd - 1.36
3rd - 1.00
4th - .80
5th - .68
6th - .55

Camber - front 2.5, rear 0.0
Toe - front 0.0, rear 0.0
Caster - 6.0

ARBs - front 40.00, rear 27.50

Springs - front 146.8, rear 1000.3

Ride height - front 6.9, rear 6.9

Rebound - front 1.0, rear 13
Bump - front 13, rear 4.0

Accel - 100%
Development - 10%

Like I said I will go into why I did what I did later on today. Give to these tune a try and you can feel the difference. Thanks again for the support!!

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I know its open sourced right above this but I shared this updated tune. It’s faster than my other S Class Syclone tune, lol.

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Hi Zepp,

I haven’t tried drag tuning yet. Very clear write up! I’ll give it a try!

Regards,
Snowman

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Thanks man. Hope it helps. I’ll be throwing some more info once I have a chance. Tearing out a nasty moldy bathroom walls and all along with cast iron tub. Tonight calls for a couple beers and hopefully a little forza if I can stay awake!! Lol

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Alright, I have a little time before work. I thought I would write up how I get my gears for these cars.

For starters, understand the how the engine your using is going to work. For example the 7.0 engine swap is a low RPM torque monster. Shift points will be at a lower RPM than what we are using for this lil project truck, 5.9 racing engine. The 5.7 is a higher reving engine, higher shift points. I’m not too experienced yet with the 4 cyl or 6 cyl engines as I haven’t build many of those yet. Basically, get to know your car. Drive it around a bit with the telemetry up looking at the peak HP RPM and peak torque rpm. I usually run up and down the Airstrip open space track. By the way, these cars are pretty fun to drift around the containers and in and out of the hangers.

The gear ratios that we already used, 2.65 final, 3.20 1st, 2.10 2nd, 1.50 3rd, 1.20 4th, 1.00 5th, .90 6th, are pretty good for just about any 5.9 racing engine car. This truck ran an 8.408 on its second pass using it. These numbers, or something very close will give you a good solid pass most of the time.

I have a few cheat sheet type reference spots that I go to alot of the time that isn’t always 100%, but has helped more times than not.

1st is a website called Wallaceracing.com .this site has a ton of automotive calculators. Many that I have no idea how to use.

What I DO use is 1st, the “tire height calculator”. For this build we have a 325/40R16 tire which is 26.24 inches tall and 12.80 inches wide. The next step is to use the “gear ratio needed” calculator. Plug in the numbers. I use 7800RPM for the 5.9, 26.24"(from the 1st calculator) and I use 165 mph as an S Class speed, but take a couple runs and adjust this as you think you need to for whichever car you’re in.

That will give you an “ideal” final gear to use, well more a ballpark to start off with. Adjust this up or down to get the launch you desire, but this can give a good starting point if you don’t know where to start.

The other reference I have is another website, “tciauto.com”. Click on “gear ratios” and this will give you actual, manufacturer’s transmission ratios. I sorta just give these a shot until I find what I like.

Thats the cheat sheet info I can give you for finding some gears for your hot rods. I just realized how late it is, gonna have to get to part 2 of this a little later on. I’ll go over how I test which gears work best, at least for me, next. Keep in mind using these websites are more “real life” info and we all know forza and real life aren’t always one and the same, lol. Thanks for taking the time to read, if ya did. Stay tuned for more!!

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Well it’s been a little longer than I planned, but I have a few while a storm moves in. Might as well try to finish this up. I’m not with my Xbone at the moment so it’ll kinda be in general terms but should still make sense, I hope. Lol

As far as gearing, beyond those websites I listed with the different calculators, I tend to start with some of those real world numbers just to try them on for size. But regardless of how I start, my final along with 1st gear is 1st priority.

As a guy that had subscriptions to hot rod and car craft and all those as a kid, I sometimes throw in some rear ends that I remember from the cars in those mags. Alot of the featured cars used to show all the gearing in the cars, dont know if they still do or not. Anyway, for example, everyone always wanted a 4.11 Posi so we’ll just start with that for this example.

Set the final to 4.11, the move 1st all the way to the left. All your gears should be .48, I think. Now move just 1st gear back to the right watching your 0-60 time. If you are trying old school real numbers, a TH350 1st gear is 2.45, then 1.45 2nd and 1.00 for 3rd. I usually throw in a .80 for 4th. This will works pretty well for any 7.0 swaps and old muscle with big, low RPM torque-y engines.

I do all my testing and tuning at the Air Strip open space to start with.

Pull up your telemetry as you are trying things out. Your goal when picking gear numbers is to keep the RPMs in the powerband of the engine. For these Hemi swaps and big block engines launching with a touch of wheel spin. When you have that right you will feel and hear it while you launch. Usually getting these cars to either drop catch or full throttle launch and hold around a 5500-6000 rpm launch and shifting into 2nd around 6500 rpm works very well. Keep trying little adjustments to find what you like best.

As you shift into 2nd you’re looking for the same RPMs that will pull all the way through the power band, from 4700 RPM-ish to 6700RPM-ish. Then the same process for 3rd gear. These big torque monster engines run better when kept under 7000 rpm so keep that in mind.

Also keep in mind that every engine behaves differently so don’t expect the same gears to work going from a 350 to a 427 to a VVT to which ever.

After gearing I will play with the suspension. Softening the rear springs from max a little seems to help with grip, could be in my head, lol. Raise the rear bump to help lower wheelie, go a little at a time. You can raise the front rebound a little as well. I sometimes will lower the rear ARBs by half or more. To me, this seems to help when a car wants to twist at launch, let’s the body roll a little keeping both rear tires on the ground.

As far as the suspension stuff, I figure things out by tons of trial and error. Most of drag racing is also in how YOU can drive the car that YOU set up or are at least used to. I couldn’t tell you for certain that half of what I am saying will work for you. It works for me but I know there are tons of faster guys out there. I use everything that the people that have taught me in every build and tune, with little touches of my own style and preferences.

Hopefully this little walk through is helpful to anybody wanting at least a starting place for drag tuning. If anybody has a certain car they can’t figure out or AWD looking for a certain time on a certain track, leave a post and we’ll see what we can come up with. I’ll do an open source build and tune on this thread or on my "Projects " thread.

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This is exactly what I needed. You have been a massive help man.

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Very cool!! Happy to help!!

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Hi Zepp,

I built your GMC Syclone and gave her a run over the weekend! Very cool! Super accel…very fun to feel the wheelie! And it is very challenging to keep the car straight! This is another nice way to enjoy Forza.

I’ve been a drag fan for most of my life. I grew up in Fremont, CA (SF East Bay) where they had a drag strip until 1988. You could hear the nitro cars from 3 miles away that sounded like they were just down the street!!! I follow the drags as much as I can these days, but the youtube channel I was following was shut down (I believe) by the NHRA. So, I can’t watch like I did. :frowning:

Anyway, I have some basic questions for how drag racing works in Forza 6. What is the best way to race? Is it through “Test Drive”? Because, as soon as the track comes up, the timer starts! There isn’t a good way to be ready for this. How about a working “Christmas Tree”? I’m thinking maybe some Forza lack of support for drag racing? Any info you could share about how best to get timed runs would be appreciated.

And I want to say, you are a great source of info for drag tuning. Very clear write-ups and insight. Really great job! Thanks a lot for all your effort, Zepp. :slight_smile:

Regards,
Snowman

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Thank you! I appreciate the kind words!! Im just passing down as much as i can because that what others had done for me. Thank XxDyno DonxX!! Or Drag Master Yoda, lol. Yeah, I love that Syclone. It’s a blast. I love drag racing myself, wish I could do it for real! As far as YouTube, check out 1320 videos. They cover alot of drag week, a bunch of the 405 crew, tons of stuff.

I agree that drag racing needs some proper love thrown it’s way and have even posted many a thread, added to wishlists, anything I could think of.

As far as testing and tuning, I’m a little opposite of Gorilla. I do almost all my testing and tuning on the Airstrip Open space track. Even during test drive, if you line up at the drag strip starting line, you will still get the full hooked launch and can work out the wheelie if there is any or switch up gears if needed. When the track loads and you can start driving, immediately turn right and go past all the planes. The start of the drag track is inbetween the planes and the hangers. From there you can hit 1/4 and 1/2 mile. To get an idea of the hook for Sonoma or Hockenhiem I will start at the 1/2 finish line and go back the other way. I start all my runs on the 10’s on the timer. You won’t get an accurate time, but after a while you will be able to tell pretty close. At least a ballpark. That way I’m not going from lobby back to the tuning menu and back to the lobby. I NEVER use the drag track test drive. Pointless, to me. All over way to fast. When I have what I feel is solid, I will get my own lobby, set it to at least 5 heats and run it. Try different launches, shifting points. The just repeat until I’m happy.

Once you find what works for you, it’ll all start being given much easier and quicker to build/tune a car.

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Okay, got it Zepp. Thanks a lot again!

Snowman

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What I do for testing is build my vehicle how I want it then go to test drive and pick Sonoma, I only run my tests on automatic with wide open throttle right from the beginning. Like hold the throttle down before it’s even done loading so that way once it loads up you’re already going. I only use the automatic so that way it takes me out of the equation with a missed shift or anything like that. Now when you tweak something go run it again the exact same way and you will consistently keep hitting the same reactions and power because of the auto and WOT. Once I get it close to where I want it and I want to know the real times I am hitting I change my assist back to manual with clutch and go online, set up my own room and hit the strip and see what I’m actually running. It’s a massive pain running this way but I feel it’s the most consistent. Some people go on tracks with long straights and time themselves and tune that way so they never actually have to leave the track. I don’t like doing that because I can’t really tell if I’m shaving off tenth a of seconds or anything. I do use it that way to tune my suspension to make sure I’m hooking up without knocking the tires off the entire way. It’s good for that and for shift points but it doesn’t tell you anything about times or speed. Hope something in that rambling paragraph helps you.

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So I built a bronco and it does crazy wheelies right off the line. Like almost flips the truck. How do I tune that out?

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Raise the rear bump until it starts to stay on all 4s. Also, not all cars will work best with full throttle launch, at least for me. Throttle control helps. I rarely leave at full throttle on any of my cars. Also keep in mind how the bronco is built. The rear axle is almost in the middle of all that body mass in the back. There quite alot of weight behind the axle, making it harder to get rid of the wheelie. I haven’t tried a bronco, I’ll mess with one, see what i can do.