Trying something a little different.
#31

Well, I did get the wheelie bar parts in.

Then I ran it without the bar because I thought it was flimsy. No GNSS results, we ran on a DTS-1 and none of the times were spectacular...
Except for the one run where I tried some prep and burned my slipper clutch the whole way. I was only a whole turn from full lock, so I finally found my traction. Just running prep never worked before. Sunday is the first big race, so I'll be going through some prep and getting some serious runs.
That said, it never once lifted the front. I even had one wreck that I'm sure would have ruined a wheelie bar. I might go all season without it.
The transmission is half on hold while I source some parts. It looks like McMaster-Carr might have the shafts I need. Also, the economy is a wreck and I'm broke, so we'll see how this all pans out...

Then I ran it without the bar because I thought it was flimsy. No GNSS results, we ran on a DTS-1 and none of the times were spectacular...
Except for the one run where I tried some prep and burned my slipper clutch the whole way. I was only a whole turn from full lock, so I finally found my traction. Just running prep never worked before. Sunday is the first big race, so I'll be going through some prep and getting some serious runs.
That said, it never once lifted the front. I even had one wreck that I'm sure would have ruined a wheelie bar. I might go all season without it.
The transmission is half on hold while I source some parts. It looks like McMaster-Carr might have the shafts I need. Also, the economy is a wreck and I'm broke, so we'll see how this all pans out...
#32

I run slipper eliminator or fully locked slipper since I tune in the radio. I've never been consistent with traction so I just condition and clean. I have done traction, set, clean, then run. That's assuming the tire is already conditioned and soft.
I use the wheelie bar and no weight on the front. Shocks have to be close and wheelie bar has to be adjusted just right. Our ground is not real flat so that's a challenge but I like the no weight added on the front.
Hope you can post some results for your runs in the race. Good luck!
I use the wheelie bar and no weight on the front. Shocks have to be close and wheelie bar has to be adjusted just right. Our ground is not real flat so that's a challenge but I like the no weight added on the front.
Hope you can post some results for your runs in the race. Good luck!
#33

I'll be going full lock if I'm still slipping. An eliminator is probably in my future but the concern right now is blowing apart transmission cases (hence five star, five seven, DRC and exotek all making metal cases now). I'd rather slip a clutch a little than rebuy all my metal transmission gears.
My tires are great, though. Two pairs of old Reactions (with the internal side ribs) with a season of break in. I can't buy tires this good, and I'm reluctant to buy more, knowing how much work it is to get them right.
For now, I'm watching the weather like a hawk... >30% chance of storms all day tomorrow...
My tires are great, though. Two pairs of old Reactions (with the internal side ribs) with a season of break in. I can't buy tires this good, and I'm reluctant to buy more, knowing how much work it is to get them right.
For now, I'm watching the weather like a hawk... >30% chance of storms all day tomorrow...
#35

Their sensor board fried... no time slips. Next Sunday it should be running though.
Blew my launch in the first round and spun out. Thought I had it down, I was making consistent launches all day during testing. Maybe it was the 10° drop from the storm rolling in, maybe I was getting too confident, maybe I was just jittery from nerves. Also, don't go racing on 4 hours sleep with a hangover.
Buuuut... I got stuck. Like, really stuck.

Had to lock the slipper down completely. Fresh, flat concrete helped a lot, but I made some passes without prep and I couldn't get any speed. I need to finally get into the launch control, I've been racing 100% manual and my trigger finger will never match what a computer can do for me.
On the other hand, my buddy, who is also running this aluminum chassis and wheelie bar, went to the semifinals.
Blew my launch in the first round and spun out. Thought I had it down, I was making consistent launches all day during testing. Maybe it was the 10° drop from the storm rolling in, maybe I was getting too confident, maybe I was just jittery from nerves. Also, don't go racing on 4 hours sleep with a hangover.
Buuuut... I got stuck. Like, really stuck.

Had to lock the slipper down completely. Fresh, flat concrete helped a lot, but I made some passes without prep and I couldn't get any speed. I need to finally get into the launch control, I've been racing 100% manual and my trigger finger will never match what a computer can do for me.
On the other hand, my buddy, who is also running this aluminum chassis and wheelie bar, went to the semifinals.
#36

I spent a few days last week looking at different drag racing front ends, learning how they work and what racers want.
My hang up has been caster. Caster is great, it makes a car go straight automatically. Drag racers want all the caster they can. Now, in a real car, too much makes it hard to steer (like how choppers absolutely suck at the expense of aesthetics, but will go really fast really straight really easy). But we don't need to worry, because a servo is doing all the work for us, right? These buggy based cars have caster and kickup. There's too much steering angle on the wheel, causing a loss of contact patch and a change in thrust angle when the wheels start to lean over. Nobody could explain these things in a way I understood, but I'm now making sense of the big words everyone was throwing at me.
So, after getting to see Five Star's new experiments, I'm starting to do a lot of thinking. I'm not completely sold on needing a dual servo setup, but I do like any way to get the front end smaller. Definitely going to eliminate the kickup and try some shorter shocks up front. Still playing around with an idea for a pushrod setup but it might be overthinking.
My hang up has been caster. Caster is great, it makes a car go straight automatically. Drag racers want all the caster they can. Now, in a real car, too much makes it hard to steer (like how choppers absolutely suck at the expense of aesthetics, but will go really fast really straight really easy). But we don't need to worry, because a servo is doing all the work for us, right? These buggy based cars have caster and kickup. There's too much steering angle on the wheel, causing a loss of contact patch and a change in thrust angle when the wheels start to lean over. Nobody could explain these things in a way I understood, but I'm now making sense of the big words everyone was throwing at me.
So, after getting to see Five Star's new experiments, I'm starting to do a lot of thinking. I'm not completely sold on needing a dual servo setup, but I do like any way to get the front end smaller. Definitely going to eliminate the kickup and try some shorter shocks up front. Still playing around with an idea for a pushrod setup but it might be overthinking.
#37

I was never a fan of caster because it sort of tilts the chassis when turning. I didn't think that was good for a prep drag car. Can't tell it was better but it didn't lift one side of chassis is turning. So when I started with no prep, I built my stretched bandit with 0 caster. Worked fine. When I went to a conventional stretched bandit with caster, I didn't notice a difference.
I hope you can find out something so I can understand it too. I'm assuming you just have to avoid bump steer and keep the Ackermann good.
I hope you can find out something so I can understand it too. I'm assuming you just have to avoid bump steer and keep the Ackermann good.
#38

Well, "true caster" is just the wheel's offset from the axle. Kicking up the front end at 30° is more akin to a shopping cart, which is "trail" and although mechanically it does make a car want to go straight, it isn't "true caster". It does introduce bump steer and mess with Ackerman angles, yes, but most people set their steering EPA to 15-30% and you rarely see a steering angle that would effect that much on a drag track.
Anyway, I decided to see if there was any point to going with shorter shocks the way everyone is. I have a Redcat Lightning I basically use as a shelf queen for my 7th Gen Celica body, so I pulled the shocks out. After a lot of fiddling...

Speaking of 7th Gen Celicas... That was my first car. I put 200k miles on it... it made my life happen for 11 years. Then we got a wicked hail storm on my birthday one year. Caliper seized. Floor jack went through rust in the frame. I'm staring at it right now in my driveway as it slowly rots away. I loved that car. I miss driving it every day.
So I straight up lost my shit this week when Shark Bodies announced they're doing a no prep pro mod 7th gen. And my birthday is right around the corner. It feels like destiny.
Anyway, I decided to see if there was any point to going with shorter shocks the way everyone is. I have a Redcat Lightning I basically use as a shelf queen for my 7th Gen Celica body, so I pulled the shocks out. After a lot of fiddling...

Speaking of 7th Gen Celicas... That was my first car. I put 200k miles on it... it made my life happen for 11 years. Then we got a wicked hail storm on my birthday one year. Caliper seized. Floor jack went through rust in the frame. I'm staring at it right now in my driveway as it slowly rots away. I loved that car. I miss driving it every day.
So I straight up lost my shit this week when Shark Bodies announced they're doing a no prep pro mod 7th gen. And my birthday is right around the corner. It feels like destiny.
#39


Good day of racing. Got my launch control setup, got my prep routine down, got some consistent times. Apparently my splitter is giving my car a huge rollout on the sensors and making my reaction times look worse than they should be. One opponent crossed the line, another flipped mid track. Figures the one to take me out would be one of the fastest runs of the day. Spun trying to slow it down and slammed a side wall... splitter survived but the bumper mount is toast.
Time to turn it up and ruin the whole setup.
Just kidding.
But seriously, I know I have room. I'm still getting confidence in the car and only now actually getting to full throttle. Not sure if I should change gearing or throw timing at it yet. I'm at 0 turbo and 35 boost, I probably havent seen what the car can do yet.
#40

Three weekends of racing got expensive. Matched my PB of 2.46 but no better. Cranked it to 43° turbo with 15° on the can. Launch power at 40%, went from 1.14s on the delay to 0.96s to 0.9s. Turbo ramp up from 1 to 2. Still running 21/87 gearing but with a slipper eliminator now. Not sure whether I want to raise my launch power or go with a bigger spur. Considering a new rotor over a new motor. I like the 4.0t and hearing the even turn motors are better. But I know running a ROAR motor is choosing to be slow. Not willing to try a 3.0t yet, afraid to blow up my RS pro and not able to replace it. Not going to try to get a DRK, since everyone seems to be getting ready for a new release.
#42

Whatever the stock rotor is for the surpass v4s 4.0t. I can get their ultra torque rotor for cheap second hand, so that's pretty tempting. I hear you can throw too much rotor in a motor, but since it's ROAR approved, I think it probably could be hot-rodded a lot more than an outlaw motor.
This is all speculation, though. Budget is my biggest restraint. Probably gonna throw a 96t spur at it and see what it can do. I need that Celica body and a new esc if I put big money in the car (>$100).
This is all speculation, though. Budget is my biggest restraint. Probably gonna throw a 96t spur at it and see what it can do. I need that Celica body and a new esc if I put big money in the car (>$100).
#43

Too much rotor I'm assuming can restrict rpm. I have a 13.5mm rotor in my 4.5T. I don't think a 96t spur is warranted for 4.0T. I would keep working with what you have. That's what I'm doing...budget restraint also. I've been playing with suspension and using the wheelie bar with no weight added to the front. The Supra? body is surprisingly pretty stable.
Forgot to mention, a good battery really helps.
Forgot to mention, a good battery really helps.
Last edited by rskoncepts; 06-22-2022 at 04:40 PM.
#44

I might need a better battery... but I'm not sure I can confirm that. Hotwire data logs are trash. On one had, it appears as if I'm getting drops as low as 6.1v... that's bad. But on that same data log, for a pass that I know I hit 100% throttle, the log says I was at a max of 60%. That's just blatantly inaccurate. Until I get a better ESC, I'm not sure I'll be able to figure out what's going on.
Saturday, I made a few test passes with the guys running the DTS-1 again. I'm almost positive they're running a longer track than 132ft... had a rough launch, corrected it, punched it, ran a [email protected] The only way that could have happened was with a 140+ feet to run. But on the other hand, I know the car can hit 70s without needing a wheelie bar, and it still drives like a freight train.
Also, I put the order in for the 0° bulkhead conversion and shorter front shock tower. I'm very curious to see how that all turns out.
Saturday, I made a few test passes with the guys running the DTS-1 again. I'm almost positive they're running a longer track than 132ft... had a rough launch, corrected it, punched it, ran a [email protected] The only way that could have happened was with a 140+ feet to run. But on the other hand, I know the car can hit 70s without needing a wheelie bar, and it still drives like a freight train.
Also, I put the order in for the 0° bulkhead conversion and shorter front shock tower. I'm very curious to see how that all turns out.