darrenjlobb's Rolling Road Chassis Dyno Project

[darrenjlobb]

Id like to build some strap retainers inside the rollers so that I can "pull" cars down into the rollers if i need to for traction, as there smooth rollers not knuled, so will need maximum traction for bigger power levels.. But will put two solid strap points at the back and do a left right criss cross up front also..

Bit more progress this evening,

Due to previous owner lack of using suitable water / maintenance, sadly the "load / unload and vent ports were all blocked to hell with crud, I've managed to clear the load and unload with lots of patiance, but sadly the vent is blocked solid, it is critical the vent works, or else air cant escape / enter as water / load level is changed... The vane that contains the small passage to allow air to pass was chocked solid, and no matter what I tried i was unable to un choke it. I removed the core plugs in the rear at the start to clear crap out, so I decided to drill through the casting, and then the vane, and "bypass" the vane passage way with a piece of copper pipe, its not pretty, but hopefully it should do the job, and is easily replaceable / changeable if it dosnt work as hoped...







I then set about starting to clean up some of the other brake components, so started out with the two heat exchanger elements, took alot of cleaning up, but seem to be good underneath all the crud!







Then the water passage ways / front covers :

[Piggy]

Ooo shiney things!!!

[Dum-Dum]

Gosh your fair cracking on with this.

[Piggy]

Is it not a coincidence that just as ruan gets his finger out with his 306...darren is putting together a dyno!?

[toseland]

How are you regulating the level in the thing (water that is)? out of interest

[darrenjlobb]

Is it not a coincidence that just as ruan gets his finger out with his 306...darren is putting together a dyno!?

To be fair, just a coincidence lol....Have been working on this for ages now, Only read Ruan was manning up and sorting his DT (not that I can talk) yesterday!!

How are you regulating the level in the thing (water that is)? out of interest

Basically there is "load" feeds and "unload" drains from the brake, controlled with solenoids...I MAY change the design in the future to a constant drain with variable intake, and sack off the heat exchangers if i find the reaction to be to annoying, but ive modified quite alot of it to try and speed it up...I explain in the videos im just editing how it works a bit...

[darrenjlobb]

Another update, put one of the brakes back together tonight, ive put this one together with the worst of all the bits, as I have acquired a new stator plate for the other brake, which is great news!

First thing was to refit the core plugs in the back of the stator to seal the feed / drain and vent lines:



Then fitted the stator plate back onto the center bore, after re fitting the springs / seat for the seal, and confirming we have clearance, which we do, yey!



Rotor back on:





Rotor / Stator housing back on and bolted down snug:



Heat exchanger and top distro back on:




Just leaving the torque arm and support bearing and drive flange to re mount and that brake is complete, and need to source some modern fittings to make up new lines, as the old plastic load / unload lines are a bit past it now!

Thanks for reading

[silverzx]

You lost me pages ago but fair play! Looks the part!

[Dum-Dum]

Thats impressive mate, I think I'd of got lost with it all by now.

[jamiek_uk2000]

Fair play, the write up is good but having the video's to go with it makes it much better. I wish I had done something like that for my car build. Dammit.

[londondan86]

Well done chap! Is that one of the 2 now built up? So does the read out currently work by somehow measuring the rate of water flow? Struggling to get my head around it!!

[Piggy]

Looking great. Amazing the size of that heat exchanger!!!

[darrenjlobb]

Well done chap! Is that one of the 2 now built up? So does the read out currently work by somehow measuring the rate of water flow? Struggling to get my head around it!!

The way any "braked" dyno works (so water brake, eddy current brake, disk brake) is basically there is a brake / brakes on the shaft on the drive rollers which "hold back" the engine, so if you imagine your steady state tuning, you WOT the car, and keep loading whatever brake you have until the car stops accelerating / sits at steady rpm, you are then "braking" the full force of the engine, so if you imagine, the full torque of the car is then acting against the brake / brakes. You then have a load cell / strain gauge mounted between the brake and the chassis to measure your "torque"...this is how torque figure is generated, obviously this is torque at the wheels once you have calculated wheel to roller ratios and then torque at the flywheel via gear / FD ratios and trans losses...

The adding / dropping of water just effects how full the stator housing is off water, therefore effecting how much load you have...

Inertia dynos just use the "speed of acceleration" to calculate hp based on the mass of the flywheel etc...but these imo arnt the best for tuning, where you want to spend time at certain rpms working on the tune etc..

Looking great. Amazing the size of that heat exchanger!!!

Heh, well if you think about it, if your steady state tuning say 200hp, thats 149kw of energy going somwhere, 95% of it is going into the water in the stator housing as heat, so it needs to get rid of it!

[toseland]

Is it not a coincidence that just as ruan gets his finger out with his 306...darren is putting together a dyno!?

To be fair, just a coincidence lol....Have been working on this for ages now, Only read Ruan was manning up and sorting his DT (not that I can talk) yesterday!!

How are you regulating the level in the thing (water that is)? out of interest

Basically there is "load" feeds and "unload" drains from the brake, controlled with solenoids...I MAY change the design in the future to a constant drain with variable intake, and sack off the heat exchangers if i find the reaction to be to annoying, but ive modified quite alot of it to try and speed it up...I explain in the videos im just editing how it works a bit...

I think that would be difficult... constant flow out, with modulated in, means there is the possibility of overfilling easily, the other option to that is to have an oversized drain and then you run the risk of not being able to fill it up


i would stick with being able to control the in and out.. close the out to fill it up, close the in to regulate the level, close the in more to regulate the out...

[darrenjlobb]

I think that would be difficult... constant flow out, with modulated in, means there is the possibility of overfilling easily, the other option to that is to have an oversized drain and then you run the risk of not being able to fill it up


i would stick with being able to control the in and out.. close the out to fill it up, close the in to regulate the level, close the in more to regulate the out...

The regulated drain is how 99.9% of water brakes work chap, the way this one works is very clayton specific / strange...the constant flow idea is much more common

[silverzx]

Well done chap! Is that one of the 2 now built up? So does the read out currently work by somehow measuring the rate of water flow? Struggling to get my head around it!!

The way any "braked" dyno works (so water brake, eddy current brake, disk brake) is basically there is a brake / brakes on the shaft on the drive rollers which "hold back" the engine, so if you imagine your steady state tuning, you WOT the car, and keep loading whatever brake you have until the car stops accelerating / sits at steady rpm, you are then "braking" the full force of the engine, so if you imagine, the full torque of the car is then acting against the brake / brakes. You then have a load cell / strain gauge mounted between the brake and the chassis to measure your "torque"...this is how torque figure is generated, obviously this is torque at the wheels once you have calculated wheel to roller ratios and then torque at the flywheel via gear / FD ratios and trans losses...

The adding / dropping of water just effects how full the stator housing is off water, therefore effecting how much load you have...

Inertia dynos just use the "speed of acceleration" to calculate hp based on the mass of the flywheel etc...but these imo arnt the best for tuning, where you want to spend time at certain rpms working on the tune etc..

Looking great. Amazing the size of that heat exchanger!!!

Heh, well if you think about it, if your steady state tuning say 200hp, thats 149kw of energy going somwhere, 95% of it is going into the water in the stator housing as heat, so it needs to get rid of it!

You could of just said that in the first place!

[darrenjlobb]

Spent a bit of time putting the air brakes back together, had a bit of fun remembering exactly how the retainers / springs all worked / went together, but once I did, it flew together, replaced a few suspect joints, and changed the way its plumbed slightly, these are the roller brakes to let you drive on / off the rollers. Originally on a lever valve, but have now mounted a solenoid, and will add a button in the dyno controller handset so you can just hold a button drive off and put controller down.






Then set about laying it on the floor, originally its all held rigid by fixing it to the floor (each pair of roller frames is separate)and although I intend to do the same, I wasnt happy with the two not being linked, so set about making a few thick plates to tie them together, that way they cant slide forward / back and will remain perfectly true with each other in all events!





Then started re fitting the rollers to the frames (heavy by yourself!) :





Haven't finished plumbing up the control system yet, but have tested with temp air feed, and all 4 rollers lock up solid, so thats good!

Thanks for reading,

[londondan86]

Wahoo!! Well done mate! Can tell the dedication if your dragging them things about by yourself to get it going!!!
So do the breaks operate by air or mechanical?

[ginge191]

It's taking shape! Good effort!

[Piggy]

Looking ace

Not going to get the rollers recoated??

[rajjinator]

This is epic, good work. I've wanted to build myself an engine dyno cell for years, even drawn up all the designs using an old eddy current brake from a bus but sadly noise will be a problem where I live.

Charlie from PPC built one on a trailer that he used to dyno his merlin engine... as you do!

Hope you get it all working dude!

[toseland]

Looking ace

Not going to get the rollers recoated??

more trouble than its worth tbh.. as soon as you start using it properly some of that coating will come off..

[Dum-Dum]

This is epic, good work. I've wanted to build myself an engine dyno cell for years, even drawn up all the designs using an old eddy current brake from a bus but sadly noise will be a problem where I live.

Charlie from PPC built one on a trailer that he used to dyno his metior engine... as you do!

Hope you get it all working dude!

EFA!!

[welshpug]

This is epic, good work. I've wanted to build myself an engine dyno cell for years, even drawn up all the designs using an old eddy current brake from a bus but sadly noise will be a problem where I live.

Charlie from PPC built one on a trailer that he used to dyno his metior engine... as you do!

Hope you get it all working dude!

EFA!!

*Meteor.

[Dum-Dum]

This is epic, good work. I've wanted to build myself an engine dyno cell for years, even drawn up all the designs using an old eddy current brake from a bus but sadly noise will be a problem where I live.

Charlie from PPC built one on a trailer that he used to dyno his metior engine... as you do!

Hope you get it all working dude!

EFA!!

*Meteor.

Yeah that. lucking stupid brain.

[darrenjlobb]

Piggy,

If I was going to do anything I would likely get the roller paint removed entirely and get the rollers grooved, but will see how traction is first, likely woudlnt be worth the expense of having it grooved, am hoping it will hold down what I need it to for now.... The paint makes very little difference / lasts five minutes..

I did acaully look into sacking off the water brakes and using a Eddy Current retarder, but unless you get a modern water cooled unit, they are fairly hopeless for steady state tuning, as they just get hot / burn up, and to get a decent one would cost mega bucks...that, and I do quite like the concept of the water brakes themselves.

Anyway, bit more of an update,

I have managed to source a near enough brand new stator, to replace the bad one, the bad news is its currently at Ruans, as he has picked it up for me, and given its level of rareness, I genuinely don't trust the UK postage service with it, so have decided to wait until xmas when I see Ruan to get that, so I cant re assemble the other water brake until then.

The cummins project is taking up most free time, the engine is now "in the landy" although not yet "on the mounts", and until it is, it has to stay outside as its to heavy for my engine crane inside so tractor only, so for that reason, dark evenings put that project to one side, so have found a bit of time to just do a few other bits and bobs to the dyno.

This evening have been working on the air control for the air brakes to let you drive on / off the dyno, and also building a hang controller for the dyno in general. I don't have an original Clayton one sadly (as win / retro as that would be) so am making use of an old winch hand control, adding some buttons, converting all the dyno to 12v control etc.

So step one was to mount another regulator, my workshops main air line is regulated, but unless im painting / doing something that requires set pressure, we generally run it at 200psi etc, to make impact guns "work", this is far and above the rated pressure for the air bags on the air brakes, so decided it would be best to put the dyno feed on its own regulator to keep things safe. So mounted that on the wall, and some fittings / solenoids for control:





The solenoid to the left is to air up, and the top one is to air down (vent).

This is the hand controller im dealing with:



Cut the plastic bit off, and made some new holes:



Mounted some new switchs, the top pair are to air up / down the air brakes, and lower buttons are to load / unload the water brakes:





Quick bit of wiring, Used some spare trailer wiring, ideal for the job as nice heavy duty outer sheaf, but has 7 internal cores, which leaves a few spare for future functions (go button for computer software etc)



Few standard issue nails on the wall to "store" the controller and job is done, no, its not pretty, but it gets the job done / fits its purpose!




Next step is to mount up the vfd's for extraction, and the water pump, start some of the main plumbing on the water pump etc, and get one of the brakes into the chassis etc.

Thanks for reading

[Piggy]

Heading to minehead on the 12th pal in the evening if you want me to bring that stator down??...have to meet me in taunton, so not to your front door but if you are wanting it soon theres an option?!

[Dum-Dum]

Good progress as ever mate.

If I was going to do anything I would likely get the roller paint removed entirely and get the rollers grooved, but will see how traction is first, likely woudlnt be worth the expense of having it grooved, am hoping it will hold down what I need it to for now.... The paint makes very little difference / lasts five minutes.

Surely it would be easy enough to just wang the rollers in the lathe and knurl them.

[Niall]

Fair play you really are cracking on with this. Be good to see it going soon!

[daniel909]

Loving the fencing nails