Tuning Your Slotworx V8

[Camber]

I thought it may be good to start an open discussion about what works and what doesn't with the cars on certain tracks.

 

We had our first race last Thursday night with a short enduro teaming the top guys with the less experienced drivers. It's a fun format which can produce some close racing, John drove really well to help get us over the line for a win. It was nice to see a reasonably tight spread of times through the field, hopefully this post shorten the gap even more.

 

Taking the body off my car, I made some small changes from the kit as it comes. First was adding some weight in front of the motor giving a total of 154.3 grams, up to and possibly over 160 grams may work depending on the track and motor.

 

 

 

I changed the "H" plate bushes to 1.6mm, removed the rear spring on the Tee plate (leaving the standard bush in position) and glued the oilites into the axle hangers with super glue.

Wheel diameters are 27.4mm rear and 26.4mm front, standard guide with no guide spacers, I didn't harden the front tyres or jig the chassis.

 

 

Some of the usual fundamentals were giving some cars problems:

 

* All parts should be deburred and checked for flatness to help everything mate together.

* Make sure the "H" plate floats freely with the body on. It should sit flat on all 4 spacers.

* The "T" plate should be free to move on the springs and not bind.

* Front and rear axles should spin nicely with minimal end float which can take some time to get right. Check the rear axle with the pinion not touching the spur gear.

* Oil the oilites.

* Make sure the body cannot touch the wheels under any circumstance.

* All 4 wheels should sit flat on the track.

* Radius the outside of the tyres to help reduce chatter.

* Ride height is 1.0mm.

* True all 4 wheels.

 

I look forward to more input from the experienced racers in this class.

Lift the lid and show us what you have done.

 

Cheers,

 

- Cam

[Springbok Racer]

Hi Cam,

 

It look to me like you are running a Fox4 with a 12:44 gearing, is that correct? Not sure what your straight length or lap length is, but it seems you get away with huge roll-out numbers at Dapto.

 

We are going to use the SRP25 motor and I anticipate a shorter roll-out as these motors like to rev and not labour under tall gearing.

 

I will post my setup on the various Queensland tracks as soon as I have a V8 together.

 

Thanks for starting this 'under-the-body' and 'bear-it-all' section. (Hi Glen and Steve, please don't take off those red undies).

 

Cheers,

 

Jan

[Pagey]

Gday Jan ,Steve likes blue undies ? Go figure , he seems other wise a nice bloke . Thanks for kind words on my paint jobs. Tips from Cam and Jim makes it easier. Happy to paint for you or Queenslanders just trying to get Dapto club guys sorted first. The racing and whole concept of what Cam has put together for us to enjoy is unreal . I am sure when you start racing your club will love them ! Cheers Glenn

[Garry J]

A word about oilite bearings.

 

Sintered bronze is porous and will hold oil but most oilites are supplied dry. Heat them on the stove and drop them in oil while hot to impregnate them, they'll work better and last longer.

[Guest jazzbell]

Hi Cam,

 

It look to me like you are running a Fox4 with a 12:44 gearing, is that correct?

 

First run on the Adelaide track was how the car was set with a 12:44 ratio. Car had a little to much roll but with a little grip the car was fine. Even the squids driving my car could manage the car with out over driving the corners. Times I broke into was a high 6.2 lap. Car averaged low 6.3's lap after lap.

 

Only change on my car was I glued and reamed front bearings to make front axel spin free.

 

The choice I made to run 11:44 for the MCN will suit all the drivers. The bench mark time for a v8 will be in the 6.4 /6.5 seconds.

 

I have some ideas for my new v8's on chassis set up, but for now the first one will remain as is.

 

One other thing I'd say is watch for oil or goo from the getting under the tee plate. You'll find the front could stick and effect movement.

 

Regards shane a

 

Team NSR

Edited March 28, 2015 by jazzbell

[Chris1810]

Have you modified the front t plate set up Shane?

[willowone]

Today I was fortunate enough to be given a hand full of laps in Shane's Slotworx V8 .... still buzzing , these cars love the Brabham track .

 

Cam , your onto a winner with these things mate .

 

Cheers

Kev

Edited March 28, 2015 by willowone

[Pagey]

Kev

 

Wait until you have a go with a full grid . Fast and close ,all the things you need for a awsome time!

 

Cheers Pagey

[Victory]

Cam has done an amazing job designing and building this new class of slot car and because of my Nissan obsession I have built Nissan Altimas in Jack Daniels and Beyond Blue liveries. I will also be supporting the Pepsi Max Ford that Glen has just painted for John as I have built the chassis for this car.

 

The cars handle very well and provide very close racing as a result.

 

My concern rests with the selection of the Fox 4 motor as the standard motor for this class. This week I picked up three brand new Fox 4 motors for our cars and after spending many hours breaking in the motors at low voltages I gave them a run on 12 volts with the tachometer.

 

Motor 1 26,569 rpm

 

Motor 2 28,391 rpm

 

Motor 3 29,834 rpm

 

Three identical motors with exactly the same break in process.

 

This variation in performance reflects the same lack of quality control that was exhibited by the early Scaleauto motors. This resulted in the Scaleauto Class having a NSR motor selected as the class motor to provide a level playing field in engine performance and very close racing.

 

Just putting my experience out there for discussion.

[Springbok Racer]

 

This variation in performance reflects the same lack of quality control that was exhibited by the early Scaleauto motors. This resulted in the Scaleauto Class having a NSR motor selected as the class motor to provide a level playing field in engine performance and very close racing.

 

 

I don't want to hijack this thread - but have to warn against misleading statements like this.

 

As for the motor choice in the V8 class - the rules also allow for the use of the SRP25 motor. Therefor the choice of what your group use is exactly that - your choice. I think the fact that Cam has selected the two different motors for choice is very wise. The manufacturers of all these motors have a habit of changing specifications without notice. When this happens, or we have a bad batch of motors, we have a choice to change to the other motor.

 

It is also true that testing rpm alone, means little. There is only one true test - put the motors in the SAME car, with the SAME setup, on the SAME lane, on the SAME night and test.

 

Cheers,

 

Jan

[Victory]

I am currently building cars to race in Adelaide at the 2015 Model Car Nationals and the regulations for that meet only list the Fox 4 motor - I would be quite happy to run the SRP25 as that is my preferred motor but it is not included in the regulations.

[Springbok Racer]

I am currently building cars to race in Adelaide at the 2015 Model Car Nationals and the regulations for that meet only list the Fox 4 motor - I would be quite happy to run the SRP25 as that is my preferred motor but it is not included in the regulations.

 

....then the Fox4 it is....

 

Jan

[Pagey]

V8 lovers

 

Another awsome weeks racing in this class at Dapto . Found this week that softer front end helped with handling. Less spring presure on two front springs by adding a slightly higher bushing was how this was achieved .did this with my own car plus helped Troy and Jules. They also said it made a improvement .love that every one is sharing info, helps to keep this great class as close as possible for the best racing ever! Have fun guys , door handle racing is the result of Cams great design.

 

Cheers Pagey

[Springbok Racer]

V8 lovers

 

Have fun guys , door handle racing is the result of Cams great design.

 

Cheers Pagey

 

....and not allowing all sorts of different bits to be used.....

 

Jan

[Pagey]

I agree Jan

 

Their is very limited chassis changes on what Cam has designed and that's what makes them close . At this early stage and that's what I thought this page was for, Iam only sharing what we have tried .there has been very few changes out of the box. The four bushings that mount the body on H plate were lowered from what Cam first supplied. Feed back ,R N D call it what you want . The boys have added a washer to raise T plate to stop it sticking if oil and crap build up . Feed back R N D ? Softer front end by using the same spring less pressure , RND . Maybe if that makes them handle slightly better Cam will change the bush he supplies . In no way do I want this chassis or class altered from what Cam has done. This has also been done in consult with him.

 

[BaVa]

After extensive testing at EE with Jan yesterday on a grippy track we found that hard springs on all 3 T-plate springs provided the right amount slide and the fastest times. The Volvo we tested has the very consistent performance SRP 25k. motor, 26.7mm rears,12t pinion and 45t spur gear. 1mm clearance frt and rear. 6grams of lead around the motor was needed to bring the car up to minimum weight.

It looks like different tuning is going to be required for the different conditions and tracks.

 

I'm also a strong advocate for the cars and rules not to be changed at all. Cam's idea of providing a close racing class is excellent.

Perhaps a review to a Mk2 in 12 months would be my only suggestion.

[Springbok Racer]

........and 45t spur gear....

 

Allow me to correct you Brucey; it is a 44T spur gear.

 

Otherwise I agree, different setups (without modification or change of parts) is the way to go for different tracks.

 

Glen, we are all on the same page here and will all support Cam in keeping this class as he had intended.

 

 

Cheers,

 

Jan

Edited April 4, 2015 by Springbok Racer

[Guest jazzbell]

The Volvo we tested motor, 26.7mm rears,12t pinion and 45t spur gear.

 

Bruce your home track anyone putting new tyres on with a 27.5mm rears and 12 :44 gear ratio will be slamming the end of straight wall, or you'll be braking way to early to allow for roll.

 

He's one that will give piece of mind for the People that drive on the Adelaide track...........Motor Speed....yes or no.

 

This is just a tunning test that I've done with the same brand motor.

 

Chosen motor at Thunderbirds is and will be the Fox4 for the V8's when racing in club racing and major events.

 

These test were done in the same car /chassis/body/tyres Motor with great test readings and a motor with readings that I wouldn't use in a car.

 

Test with fast motor in the car ,super fast. Next test slower motor in the car with quicker times. Reason,slower car with this fixed gear ratio of 11:44 and brand new tyres at 27.5mm I could drive the ring off it . Harder into the corners,Faster coming out.

 

Test with the quick motor s#!t loads of speed with not enough brake though. To much roll. Time lost braking to early. Being fixed ratio the only way to solve this problem is changing tyre diameter in some more testing next time at the track.

 

Regards shane a

 

Team NSR

Edited April 4, 2015 by jazzbell

[Springbok Racer]

 

Bruce your home track anyone putting new tyres on with a 27.5mm rears and 12 :44 gear ratio will be slamming the end of straight wall, or you'll be braking way to early to allow for roll.

 

Regards shane a

 

Team NSR

 

Shane,

 

I agree, the 12:44 ratio with 27.5mm tyres will not be the go at EE.au However, with the smaller diameter wheels (which mean we can use our old Scaleauto wheels when they get too small on that class) the rollout, drivability and feel, is good. It is the intention to leave the pinion 'open' at this stage until everyone driving at EE.au have worked out what the preferred pinion should be - no good nominating it too early. Afterall, if we don't allow experimentation at club level, then where and how will we get the right answers.

 

To aid us in all the above is why we are using the SRP25 motor; it is consistent, long lasting, reliable and very drivable. Given these credentials, it make for parity between all our drivers when we test the 'other' variables in this class.

 

Cheers,

 

Jan

 

Ps - can you guys who now have many bodies running, give us the weights of all the bodies (including body mounts, but please also specify whether you are using a roll cage or not).

Edited April 4, 2015 by Springbok Racer

[BaVa]

Using the srp25 takes the 'luck' bit out of the equation for a fast car. All the srp's I've bought and tested, under load,are within a couple of % of being the same. I don't have to worry about the huge rpm variations etc as it doesn't seem to happen, which makes it fair [and fun]

I'm Still happy to use a fox4 elsewhere though, and hope I get Lucky........

let the bullets fly....

[Guest jazzbell]

Don't get off track here. I'm not on this topic to compare motors this is a tuning topic for the sloworx V8's on the Adelaide track.

 

My testing resulted in the car handling with a fix gear ratio and the 27.5 mm tyre with a slower motor was a faster cornering car. So a turning tip if you get a fast motor when on the Adelaide track,you'll have to play with your diameter on the rears

 

 

Regards Shane a

 

Team NSR

 

 

[BaVa]

As I said in my EE tuning post.

Different tracks will require different set ups.

[Springbok Racer]

Don't get off track here. I'm not on this topic to compare motors this is a tuning topic for the sloworx V8's on the Adelaide track.

 

Regards Shane a

 

Team NSR

 

As I said in my EE tuning post.

Different tracks will require different set ups.

 

Exactly, this is a tuning topic for the Slotworx V8's on all tracks and both the Fox4 and the SRP25 motors are legal according to the rules - the choice is yours and your group's. Everyone contributing to this thread is entitled to their opinion and may state their findings and results with either.

 

However, whilst I don't support a comparison of the two motors on this thread - it will happen, sometimes.

 

Please continue to let us all know what you are doing with your V8's, no matter the motor you are using.

 

Cheers,

 

Jan

[Springbok Racer]

Hi guys,

 

In answer to my own question, earlier; the body weights (including body mounts) seem to vary between 23.4 and 25.1g (from the six I have weighed so far). All without roll cages. The reason for these differences lie mostly in the method of mounting the interiors and rear tank/diffuser, with also some being in the body mounting rubber used.

 

Basically, the rolling chassis is around the 122 to 124g mark. Differences here being; wheel inserts, leadwire, guide nuts, gears, axle lengths and tyre sizes.

 

I found on the first five cars that I've now prepared for racing, that I needed between 1.0 and 3.2g of extra weight to bring the cars up to the minimum of 150g. That is a nice margin for tuning purposes and changing of the car balance.

 

BTW, a rollout of around 22.5mm seem to feel right on Ecurie Elite.au and I would suggest a starting point of around 23.5mm for Red Racer.

 

Let the racing begin....in Queensland.

 

Jan

Edited April 7, 2015 by Springbok Racer

[jimmyslots 1950]

Here's a little tuning trick that I use for the Slotworx,when we first started racing the Slotworx we noticed a lot of cars were rattling around corners & knowing the chassis was not the problem it had to be in the body.With so much lateral movement in the body & chassis a quick fix for the body was to tape a small piece of body mounting rubber between the body & interior restricting lateral movement.On inspection most bodies looked to have plenty of clearance but with grippier tracks the body flexes much more as the corner speeds are greater.The front wheel arch is an area to look at & I found it has a lot of flex but so far I've only cut the arch a little bigger without spoiling the look of the car which is most important.Cheers Jimmy :D