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McPappy Racing

347K views 2K replies 205 participants last post by  HitmanIII 
#1 · (Edited)
First, I'd like to thank everyone for participating in the original McPappy Racing (2008) thread. I'm starting a new thread without a date in the title (this forum doesn't let me change the original title). The old 2008 thread still has a lot of valuable information. As of the time of this posting, it has 1614 replies and 142,924 views.

In our continual efforts to provide excellent products, I'm happy to announce the release of the McPappy Racing Dart 2.5!
McPappy on Facebook

New changes for the Dart 2.5 Kit
Last year, across the country, many oval pan car racers have been struggling with too much weight transfer to the right front, picking up the left wheels, or even traction rolling. This happened when the rules changed from 41 oz to 36 oz to accommodate the lightweight single cell LiPo battery. We went from the heavy NiMH 4-cell packs and 2-cell LiPos down to a single cell LiPo. No longer having the heavy packs keeping the left side of the car down, racers discovered these handling problems with most pan cars. When running a mere 36 oz, we lost a considerable amount of left side (and forward) weight percentage. This new Dart 2.5 was designed specifically to address these problems. This new 2.5 car will run flatter and turn harder. It provides more left side grip than ever before.
  • The Dart 2.5 offers an offset T-plate and now a super offset T-plate position. We removed the centerline T-plate position. This also moves some weight to the left even more (all 3 shocks, center shock mount, T-plate, float bridge, supporting hardware, etc.)
  • We shortened the wheelbase a lot with the Dart 2.5!. You can slide the wheelbase anywhere from 9.75" - 10.06" (as opposed to 10.03" -10.32" with the 2.0). A short wheelbase allows the car to turn hard. (Imagine how poorly a dragster would turn on an oval track.) Traditionally, a short wheelbase can make a car too squirrelly, but we were able to get away with this for a couple of reasons. First, we took advantage of the Dart's notoriously excellent rear grip. The Dart's ultra low rear roll produces more rear grip than other pan cars as it keeps more weight on the left rear in the corners. (On the scales pan cars can look similar, but if you could weigh the LR in the corner, you'd see there is more weight due to the physics of a low rear roll center.) Secondly, the front locator track width adjustments lets you fine tune how much weight gets transferred making handling changes easy. When the car is handling right, you can get away with a short wheelbase and take advantage of it's turning capabilities.
  • We shortened the "neck" of the chassis so that the carbon fiber flex braces are now the same size (2.55") as the clamp links (CRC or Associated) giving you lots of possibilities.
  • We added new rubber o-rings designed to work with the carbon fiber flex braces which eliminates all tweaking.
  • Both motor pod plates were lightened some more.
  • The left motor pod plate was designed to get easier access to the T-plate nut.
  • The LiPo strap brace was moved to the rear of the battery allowing the battery to move toward the LF wheel. This increased front weight percentage.
  • The left side of the chassis was moved out .100" to increase the left weight percentage and also taking advantage of the newest Protoform D-HD nationwide body.
  • We added new standoffs to flatten the angle of the side shocks. In our testing, this has proven to be better.
  • We added an extra front hole in front of the battery and filled in the carbon fiber near that area giving you lot's of options to use small carbon fiber braces (shown in more detail below)









We've released a Dart 2.5 Standard Kit and a Dart 2.5 Team Kit.
A comparison chart showing the differences of all of our kits is available here.

Merry Christmas!!
 
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#3 ·
Supertruck, if you are just going to get your game on in 17.5 truck, I suggest a Dart 1.0... There is prolly some around for sale, well maybe, but I will tell you that we have a few left in inventory at McPappy.... Sign in at McPappy.com ( you can just click at the bottom of my profile ) and James will hook you up.....

Anything you need, never be afraid to ask, we are always here to help....

Peter
 
#10 ·
James

Thanks for the great time on the phone today.....You are truly an exceptional guy with a WONDERFUL product. I can't believe how well thought out this car really is. I can't wait to get mine soon..... maybe Santa will have it under the tree this weekend :p:p:hat::hat::hat:

Thanks again...

Barry
 
#15 ·
Merry Christmas to you to James and the rest of the gang at McPappy.... I can't wait to get it.. I can't believe it was shipped an hour after it was ordered! Talk about FAST service!

BTW..... mine will build much slower..... I can spend a whole evening just getting a body cut and mounted right..... along with getting the posts just right. Hope to have it built for our next race on the 8th..... if I like it I may get crazy and go to Snowbirds. Haven't decided yet. Just back into this for a month after a 5 year break from racing. May give you a call sometime and chat..... thanks again James.

Barry
 
#19 ·
Can someone help me with the front axles? I have always used 1/8 axles on my cars before..... but my new 2.5 came with the AE 3/16 inlines..... do most use these or swap them for 1/8s?

If you use the 3/16s.... how do you get the plastic nuts on straight and make clean contact with the bearings? Do you need shims behind the bearings too? Do you use the set screws on the pretty polished kingpins?

Thanks and MERRY CHRISTMAS to all

Barrry
 
#20 ·
I used to use 1/8" axles all the time too. When I first started manufacturing these cars, I thought about switching my personal McPappy cars over to 1/8" axles. But then I realized that the 3/16" are much lighter as they are aluminum. 1/8" axles are usually steel. I've only found 2 titanium 1/8" axles. Lunsford's titanium axles were a bit too short and the outer bearing rides on the threads (not centered well). I ordered some T2C titanium front axles and they gave me steel, probably on accident, so I can't speak for those axles.

The only downfall that I've heard concerning 3/16" bearings is that they are less durable. Probably because they use smaller balls and can dent the inner race easier. Personally, I have not seen this to be the case. The last few years I've been racing with quality drivers and I don't hit things that often, so maybe I'm not the best judge of their durability. Lately, the only bearings that I find to go bad often are the rear bearings.

I believe it's more important to save weight everywhere possible on the car so that we can run as much tungsten as possible. So I've been very pleased with the light 3/16" axles. You will not need to use any shims as the McPappy locators will be the better way to adjust track width. As for the nut, I hear ya. That plastic nut is a pain in the butt. I push it on while using the nut driver and it goes on pretty straight most of the time. I also take it off and use an Xacto blade to trim off any plastic that bubbles up after you thread them on the first time. Most people do not use shims with these plastic nuts.
These plastic nuts are also an alternative.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&W=000330796&I=LXBMG7&P=K

Personally, I use metal 5-40 locknuts like these:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&W=000330796&I=LXNTG1&P=K
I was lucky to get some aluminum ones from a friend who had them for 20+ years. It's impossible to find aluminum 5-40 locknuts these days. If anyone knows of any, let us know!

Merry Christmas everyone!
 
#31 ·
I used to use 1/8" axles all the time too. When I first started manufacturing these cars, I thought about switching my personal McPappy cars over to 1/8" axles. But then I realized that the 3/16" are much lighter as they are aluminum. 1/8" axles are usually steel. I've only found 2 titanium 1/8" axles. Lunsford's titanium axles were a bit too short and the outer bearing rides on the threads (not centered well). I ordered some T2C titanium front axles and they gave me steel, probably on accident, so I can't speak for those axles.

The only downfall that I've heard concerning 3/16" bearings is that they are less durable. Probably because they use smaller balls and can dent the inner race easier. Personally, I have not seen this to be the case. The last few years I've been racing with quality drivers and I don't hit things that often, so maybe I'm not the best judge of their durability. Lately, the only bearings that I find to go bad often are the rear bearings. ....
Merry Christmas everyone!
As a little anecdote, I've always run 1/8, but thought the new 3/16 CEFX axles looked kind of trick so I gave those a try. I had the left front bearing come apart 7 laps into the main. Can't remember any contact (I'd think it would have been memorable to be on the LF) so I was at a loss, and they came off the car. The ASC ones are probably better in that regard though as you get to run a larger nut on it rather than a button head screw and washer like the CEFX ones.

Should get the 2.5 on track tonight, looking forward to it!
 
#21 ·
James,

Thanks for the great advice..... I spent some time with my axles last night while I was waiting for the kids to go to bed.... Santa won't come till they are asleep!

Anyways, I forced the plastic nuts on several times and the chucked them in my lathe. I squared them up and then cut down the 3/16 sleeve so the wheels fit without shimmimg the inside of the bearings..... got a great fit on one side..... will get to the other one after things settle down....

What size tires should I being using for setup? I know this is preference but looking for advice here.......

Barry
 
#23 ·
Barry,

Yes, i have been using one washer approx 0.050" on each stud before they go up thru the bridge. If not, there is not enough clearance and the tplate motion is restricted due to the 2-56 screws hitting the underside of the bridge. Shortening the 2-56 screws to be flush with the plastic ball socket will also help.

James or Dom, please chime in is there is a better way.

John
 
#25 ·
Yes, there are 2 gold washers included in the kit for this purpose. They are perfect for the pivot ball diameter. I think they are .030" thick if I remember right. I also take a teeny bit off of the upper pivot ball socket posts (shaved at an angle).

As for tires, I run 3 BSR pinks and a purple. 2.24" rears, 2.20" LF, and 2.18" RF. But that's just me.
 
#26 ·
Guys

Thanks for the help........ I have muddled my way through most of this build.... most of it makes sense to me but I would prefer to ask. I had put the gold washers under the t-plate. Still have some alum washers I think....... will swap them then.

I did some searching last night..... I haven't looked at mine but could I have the short pivots? Seemes like 30thou is not enoough gap to make the rear pod flush with the chassis...... but it would get the pivot carriers up flush but raise the roll center.... guess I can do what I want to really..... but I appreciate the help. Will try one washer and then see.....

So James..... those are big tire sizes I would have thought..... now I have noo carpet experience but a local track guy set me up with some used BSRs he had and trued them to 2.15...... just ordered some WGT specs and they came at 2.20 approx..... now my calipers say 2.24! Hehehe


Any suggestions on ride height spacerrs? I can see two under your front end.... what size? Just looking for4 some expert advice here..... could get there.... but like advice

Barry
 
#28 ·
Thanks for everyones help here.... I now have a gorgeous roller! It seems like everything is working together in harmony.

I did put the gold washers on the pivot stud and all is perfect. Did a little tweaking and I think it will be good. Settled on #2 axle locators.... a little high but that may change with the weight of the electronics. Still not certain on front spacers/ ride height but I think I am close.

Thanks again

Barry
 
#29 ·
Been just drooling over my 2.5 roller for a day now..... can't wait to put electroincs on it. I keep looking at it and the closer I look the more design features I see!

This car is REALLY WELL DESIGNED! Now I am always one to change things for the better but I didn't find much to do.

I will say something that I found very helpful.... Micromesh pads..... they are very fine sand paper for polishing... like 12k to 30k grits. I know James swears by Simichrome but this stuff on my shock pistons made them just glide and my pivot balls and kingpins just move like I have never seen before. I know this is a wonderful car but I may be bias in saying this but this one is SMOOTH! Have my body coming tommorow so I will have more work to do..... still waiting on a new motor to drop in it.

Barry

A VERY happy McPappy owner;)
 
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