|
|
Post by dave632 on Dec 18, 2016 11:04:29 GMT -7
|
|
|
|
Post by SKR on Dec 18, 2016 13:00:56 GMT -7
looks like we think alike Dave. I made something similar a few years back. I was looking for a way to take wheel RPM's as well and like you said, it's nearly impossible try to take readings straight from an HO wheel. One thing I added to mine was screws underneath the traction magnets so I could adjust the down-force. The red splatter is from Slayer tuning up for the next event. 
|
|
|
|
Post by dave632 on Dec 18, 2016 13:49:41 GMT -7
Wow, looks like you pirated an old brass slot car chassis for the rear mount just like I did. Very similar design.
Looks like the Slayer had a little tuning problem!!! I am sure it will be ready on race day, looking forward to the
match up again.
I was afraid to touch the Nomad and did not even take it apart for a cleaning. I did make a couple of test passes with
it and it was still running good. It will run exactly as it was at my race.
Once I get the rest of the dyno setup I will show a wiring diagram and some dyno results. Parts were just ordered so it will
be a few weeks.
|
|
|
|
Post by SKR on Dec 18, 2016 18:32:49 GMT -7
lol, actually I haven't touched Slayer yet. I did use an old 1/24 scale motor mount. I'm really surprised at how similar ours look, not ever seeing pictures of each others.
|
|
|
|
Post by AJR on Dec 19, 2016 7:05:21 GMT -7
Good stuff here for sure. I don't know how many times I've said that before on the forum. This is the kind of stuff I like....self built test equipment. Uncanny how the two set ups resemble one another. Are you having to do a calculation for the difference in diameters in the two tires?
|
|
|
|
Post by dave632 on Dec 19, 2016 10:49:40 GMT -7
It really is remarkable how alike they are using several similar parts.
The rear wheel diameter on the dyno is .9" which is about twice the diameter of the average HO wheel. There are two reflective strips on the "flywheel" giving an approximate 1 revolution for 2 turns of the HO wheel. If you wanted the actual rear wheel rpm you would have to divide the diameter of the cars wheel into that of the dyno's and calculate it from that. Since I am just worried about tuning the cars the actual rpm is not that important. It will still be relevant since any improvement in the car would show when tuning and the speed of the dyno wheel would be comparable between cars. Since I have MPH on my strip I will do some comparison between Dyno rpm and actual speeds reached.
|
|
|
|
Post by AJR on Dec 19, 2016 16:10:52 GMT -7
That's what I was wondering. If you were going for an actual number or relative number for tuning. Makes sense. Thanks for sharing Dave.
|
|
|
|
Post by GTS on Feb 17, 2019 10:46:43 GMT -7
Wow, looks like you pirated an old brass slot car chassis for the rear mount just like I did. Very similar design. Looks like the Slayer had a little tuning problem!!! I am sure it will be ready on race day, looking forward to the match up again. I was afraid to touch the Nomad and did not even take it apart for a cleaning. I did make a couple of test passes with it and it was still running good. It will run exactly as it was at my race. Once I get the rest of the dyno setup I will show a wiring diagram and some dyno results. Parts were just ordered so it will be a few weeks. Dave, This is pretty interesting, thinking about putting one together.
Is this still a valid tuning tool for you? If so, is there anything you wish you had done differently? |
|
|
|
Post by dave632 on Feb 17, 2019 10:57:14 GMT -7
I did not show a picture of the current draw and voltage readouts. I would have liked a
better way to hold the car to the tester as it does move around some causing some slippage.
I do not use the dyno that much but it will show rear wheel rpm, current draw under load
which can be of some use. It was fun to build and I did pirate an old chassis jig to make it.
I can send you a picture of the readouts if you like.
|
|
|
|
Post by sandfly on Feb 17, 2019 11:25:10 GMT -7
Hi we purchased a VRP 3 special edition and I use it for bench testing as most of my cars have their rpm recorded, so a new build can be compared, it's a great tool useful for checking rear wheel ovality or imbalance.
|
|
|
|
Post by GTS on Feb 17, 2019 11:36:47 GMT -7
I did not show a picture of the current draw and voltage readouts. I would have liked a better way to hold the car to the tester as it does move around some causing some slippage. I do not use the dyno that much but it will show rear wheel rpm, current draw under load which can be of some use. It was fun to build and I did pirate an old chassis jig to make it. I can send you a picture of the readouts if you like. Yaw, don't know for sure how much I would use it either but sure looks like a fun project . If you don't mind, sure any pics or other info you have, I would be appreciative of you sharing. Maybe a schematic of the voltage & amp gauges where you hooked them in, also? Thanks Dave!
|
|
|
|
Post by GTS on Feb 17, 2019 11:43:50 GMT -7
Hi we purchased a VRP 3 special edition and I use it for bench testing as most of my cars have their rpm recorded, so a new build can be compared, it's a great tool useful for checking rear wheel ovality or imbalance. Those are cool  ! Yaw, if a half dozen guys went in on the purchase of one, that would make it more doable, for sure. I'm envious  .  |
|
|
|
Post by dave632 on Feb 17, 2019 12:37:00 GMT -7
I will look for some of the information on the build.
|
|
|
|
Post by sandfly on Feb 17, 2019 13:54:19 GMT -7
Hi we purchased a VRP 3 special edition and I use it for bench testing as most of my cars have their rpm recorded, so a new build can be compared, it's a great tool useful for checking rear wheel ovality or imbalance. Those are cool ! Yaw, if a half dozen guys went in on the purchase of one, that would make it more doable, for sure. I'm envious . Mmmm not cheep when u convert to NZ dollars and POSTAGE |
|
|
|
Post by dave632 on Feb 17, 2019 15:49:39 GMT -7
|
|
? in my opinion and they will not
Rear wheel dyno
Driven wheel
Flywheel
Power pick up
Car on dyno
Wheel RPM
? in my opinion and they will not
!
. 
