Search found 50 matches
- Thu Jun 04, 2009 9:43 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Choosing a Data Logger
- Replies: 18
- Views: 26476
Re: Choosing a Data Logger
Jason, I am sorry you had a bad experience with RPM. The last time you blasted me on this forum, I asked you to please contact me and I would do whatever was needed to fix the situation. Never heard from you. I remember our discussion regarding the EGT problem, and the symptoms, test conditions, and...
- Fri Apr 10, 2009 10:31 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Any experience with on-board dynos?
- Replies: 4
- Views: 11616
Re: Any experience with on-board dynos?
I spoke with them a couple years ago and they didn't have a unit that would work with other data loggers, but on their website (pricing) they now offer a 0 - 5 volt version for $3995.00. It would be very interesting data. I'd like to get one for testing, but the price is still too high for most of o...
- Wed Apr 01, 2009 3:11 pm
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Unleaded Racing Fuel
- Replies: 8
- Views: 15932
Re: Unleaded Racing Fuel
The O2 sensors are good for several hours of run time with leaded fuel, which is a lot of passes. Do the free air calibration regularly, as the sensor will drift with use. If the sensor is too contaminated with lead, it won't free air cal correctly. Target EGT temps will vary with combustion chamber...
- Fri Mar 20, 2009 10:28 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Stick Shift Question
- Replies: 6
- Views: 13147
Re: Stick Shift Question
James, Clutch slip can be read with Engine RPM and Drive RPM as long as the trans is not a lenco style with clutch packs on planetaries, which can also slip. The attached graphs show Engine RPM (red line), Clutch RPM (brown line) and Drive RPM (blue line). Also, in the lower portion of each graph, i...
- Sat Dec 27, 2008 11:20 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: TPS ??
- Replies: 4
- Views: 11803
Re: TPS ??
Unless you have something unusual going on like John did, you are correct. It will show you if you lift, when you lifted, how much you lifted and for how long.
Randy
Randy
- Fri Dec 12, 2008 5:17 pm
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Randy McMahon and others with loggers
- Replies: 10
- Views: 17263
Re: Randy McMahon and others with loggers
Lets consider some other factors for a bit. With the power you have, the converter initial stall is about 5500. This converter, from 4000 to 5000, it is not coupling nearly as much power. The initial tirespin, in the first tenth or two is aided by the fact that when the tire "wads up", the...
- Wed Dec 10, 2008 2:12 pm
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Randy McMahon and others with loggers
- Replies: 10
- Views: 17263
Re: Randy McMahon and others with loggers
Sorry for being so late in responding. You are correct, the data indicates that the rear end extends at the hit and plants the tire, then the car squats down as expected. But then, the rebound reduces the actual weight on the tire and you get more tire spin. As evidenced in your G meter by the dip a...
- Thu Oct 09, 2008 10:34 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Beginer questions.
- Replies: 6
- Views: 14055
Re: Beginer questions.
Do you have a shift chip or light? If so, and the tach agrees with the it, I would suspect the logger since two other instruments agree. The O2 readings are seldom completely stable. a variance of .2 to .4 is often the case through a run. Look to see if the varyance is coresponding to RPM. For examp...
- Mon Sep 01, 2008 7:04 pm
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Why not to buy a rpm system
- Replies: 9
- Views: 20805
Re: Why not to buy a rpm system
Racingj, I really have no idea where this comes from. If I spoke with you, and left you feeling that way, I should be horsewhipped. You have my sincere appologies for not providing the support you needed. It is our primary goal to do whatever it takes to help our customers. We will replace whatever ...
- Tue Jul 29, 2008 1:17 pm
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Trans Input Shaft RPM Logging
- Replies: 6
- Views: 14488
Re: Trans Input Shaft RPM Logging
The magnet (just 1) is installed in the input shaft. Typically, this is done by Lenco. You can send them your shaft and they will install the magnet. They will need to know the depth of your can and which type candlestick you have.
Randy
Randy
- Thu Mar 13, 2008 9:06 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Wide band
- Replies: 2
- Views: 11128
The wide band O2s do have advantages over EGTs. The EGT target temperature will vary according to combustion chamber and piston combination, but the O2 is reading direct Air Fuel ratio, and is more consistent. In typical installations, one O2 in each collector is sufficient, however you need to cons...
- Mon Dec 31, 2007 11:22 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: O2 or ex. temp?
- Replies: 8
- Views: 16578
Generally, the O2 sensors provide more specific mixture information than the EGTs. The drawback is that they cost twice as much. Adding 8 EGTs to a data logger is about $900, while, for 8 O2s, the price ranges from $1800 to $5000. If you are trying to determine if the manifold is equally distributin...
- Mon Sep 17, 2007 9:51 am
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: signs of oxygen sensor going bad
- Replies: 3
- Views: 12724
Todd, When the sensor starts failing due to lead contamination, you will get very inconsistant readings, and it will not calibrate. It's a good idea to calibrate the sensor occationally to correct for the minor changes that may occur due to the leaded fuel. I do mine about every 20 laps. If the sens...
- Tue Aug 28, 2007 3:30 pm
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Logging shock/strut travel
- Replies: 22
- Views: 33004
Michael, The guys are right, 100 samples per second is minimum for a rear shock travel sensor. The 12/sec will miss the information you need, mainly the initial extention, set and rebound. If you just want to know the final set extension/squat, it will show that. The low cost sensors mentioned will ...
- Fri May 04, 2007 6:18 pm
- Forum: Data Logging - Randy McMahon RPM Performance
- Topic: Data logger
- Replies: 14
- Views: 24179
Thanks for all the good things being said about our RPM Performance data logger. Its good to know our work is appreciated. I understand there are many data logger brands out there, and the choice is not easy. I have heard horror stories about the way some of the companies have treated customers. I c...