Scottie-GNZ Posted February 13, 2001 Share Posted February 13, 2001 I recently scanned the latest Car & Driver and the cover screams 0-60 in 3.6 for the Mosler MT900. They also claimed 350hp, 2575 lbs and a 1/4-mile of 12 @ 118. I threw those numbers in my cababulator and it spit out 350.7+RWHP. Hot damn. BTW, I assumed that weight was w/o driver so I used 2750lbs assuming those guys wear lightweight Guccis . That weight comes close to mine so I wondered how I matched up in 0-60 and used my datalogger to show it. The datalogger has my final drive ratio and tire diameter and reads speed from the car's VSS. By "zeroing" out the 1/4-mile run with a starting point of when the computer first senses speed, it can correlate time to speed and distance and come within .01-03 of the real timeslip. Here is a pic of the run at exactly 60mph. Here you are seeing 5 of 13 parameters that can be replayed and you can trace the entire run at 18 frames per second. The 13 parameters are Speed, Inj pulsewidth, Boost PW, EGR DC, Battery Volts, A/F ratio, Spark Advance, Spark retard, Knock Count, O2 volts, Accelertaion, HP and torque. The big readouts on the right side are the vitals that are always there. So, by holding down the arrow key and srolling to the right, you can see the vitals or whatever 5 parameters you want to put up for the entire 1/4-mile. The value of the parameter at the vertical line is positioned at the top right of the graph and at the bottom you see time and distance. To give you an idea of the spoolup problem, note the distance from the first indication of speed to the vertical line, then go left from the same starting point to the time that the TPS is wide open and it looks like about the same timespan. That means I had the transbrake activated and my foot flat to the floor for 3 secs waiting for the hair dryer to spool up and the RPMs are just barely creeping up at about 2200RPMs and the boost gauge is registering about 1.5#. Anyone ever held their brakes and floored their car for 3 secs? Sorry if this bores anyone, but I thought someone out there might appreciate it. ------------------ Scottie 71 240GN-Z Scottie's GNZ Quote Link to comment Share on other sites More sharing options...
DavyZ Posted February 14, 2001 Share Posted February 14, 2001 WOW! I can appreciate this, but I'm not sure I completely understand it. Bottom line is, 0-60mph under 5 secs is fast, and under 4 is insane! You are in the low 3's!!! You may need a neck restraint or something at the track, Scottie. If I can get my Z to do 0-60mph in under 5 secs, I'll do a Snoopy dance of joy and then blow away every riceboy in town. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted February 14, 2001 Author Share Posted February 14, 2001 Anyone want to venture a guess what Ron Jones' 0-60 time is? I am guessing 2.0-2.2. ------------------ Scottie 71 240GN-Z Scottie's GNZ Quote Link to comment Share on other sites More sharing options...
Guest RON JONES Posted February 14, 2001 Share Posted February 14, 2001 Over on Prestage.com they have a few pretty cool Car math calculators.If you punch in my 1.25 60ft,the calculator tells me I'm going 65.35MPH.So I guess I'm going 60mph in a little less than 1.25 seconds.fun fun fun! Quote Link to comment Share on other sites More sharing options...
John C Posted February 14, 2001 Share Posted February 14, 2001 I'd say its the most fun one can have from the waist up!Gotta love those g's! Quote Link to comment Share on other sites More sharing options...
Drax240z Posted February 14, 2001 Share Posted February 14, 2001 Just some more fuel for the fire here. Joe Amato Top Fuel dragster. (courtesy of June 2000 road and track) 0-60mph = .8 sec (takes 31 ft... the car is damn near 31ft long!) 0-100mph in less than 1 second. 660ft - 275mph 0-300mph = 3.6 seconds 1320ft in 4.51 at 326.67mph. 4 G's sustained for the first 660ft or so. If I remember correctly you see about 3G's in a space shuttle launch. Mind boggling. ------------------ Richard Lewis 1972 240z - L28TURBO transplant ongoing! Drax's 72 240Z Turbo Quote Link to comment Share on other sites More sharing options...
DavyZ Posted February 14, 2001 Share Posted February 14, 2001 Thank you, Joe, for making us all look slow Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted February 14, 2001 Share Posted February 14, 2001 Yeah, probably Brown Trowser time for most of us mortals.. Top fuel is insane, but would be fun to do once if it was'nt something you could die at instantly (or at least rattled so hard you'd never forget it, Eddie Hills near 300 mph blowover comes to mind)... Lone [This message has been edited by lonehdrider (edited February 13, 2001).] Quote Link to comment Share on other sites More sharing options...
clint78z Posted February 20, 2001 Share Posted February 20, 2001 I think Scottie likes looking at the graphs almost as much as racing . I like the numbers as well . I was just looking over the charts trying to see if I could spot anything wrong . It looks like the car is tuned very well from info given . The one thing I noticed with the launch is that O2 voltage is below .5 mv when at the lights . Could this be why it is not getting enough rpms with the transbrake ?? Probably need a graph of the MAP sensor . Good luck tracking the problem down . Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted February 20, 2001 Author Share Posted February 20, 2001 Clint, I like your thinking, but I believe you are misinterpreting what you are seeing and that is understandable. Now, not only do I like looking at those graphs but I live and die by them and my engine lives because of them . Although the large text on the right appears to correspond with the graphs, they do not. They are the key parameters that I want to have always displayed. Each graph, numbered 1-5 on the left, has its function identified at the top-left. The range of each graph is on the right side and the current value (the vertical line) is on the top-right. Graphs #4 & 5 are LV8 (load value) and MAF and by pressing the 4 or 5 key I can change them to display any of the other parameters. The only O2 value displayed in the graph is in big text and the 749mV value corresponds with position of the vertical bar and it is a tad low. If you could have seen the O2s at spoolup, they would have been low too because I had the chip programmed for quicker spoolup. At spoolup, it reads the VSS and senses no speed but also senses the TPS open, so it leans out the mixture and retards the timing until it senses movement then goes into another mode table. That was not my spoolup problem however. I pulled the turbo off again and inspected the wastegate housing and the entire puck has a nice clean, even exhaust color to it, which is bad!!!! What it should have is a nice neat color in a perfect circle formed by the wastegate hole and the outside of that ring should be a different color. This means the puck was never seated over wastegate hole and the little boost I was trying to build at spoolup was just going pass the wastegate. Problem fixed and we will now see just how much grip 275 BFG DRs have. ------------------ Scottie 71 240GN-Z Scottie's GNZ Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted February 20, 2001 Share Posted February 20, 2001 A couple of g's in a car is pretty awesome. The feeling of being put back in your seat really can't be beat, while you are on the ground anyway. I'm a pilot and have flown some aerobatics in the past. If you have any pilot friends go up with them and ask them to pull some g's. You can pull 3 g's in a normal airplane and not break anything. Try raising your arms at the same time. There is nothing like turnin the world upside down in an airplane. Short of the mile high club it's the most fun you can have up there! ------------------ Chris Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted February 21, 2001 Share Posted February 21, 2001 i have found some high tech racing efi units that have data logging and have down load the sample software but that stuff is hard to learn to use.how long of a data stream can you record scottie?when i get my other turbo motor built up i would like to look at some laps at thunderhill-or at least the 4000 ft straight. Quote Link to comment Share on other sites More sharing options...
clint78z Posted February 21, 2001 Share Posted February 21, 2001 When I was looking at the graph I "ASSumed" that the 749mv was max and Omv was min . Then I looked at were the launch speed was 0 . Just before launch I thought that the O2 voltage was below 500mv . This would indicate a lean mixture, a shot in the dark . Good to see you straightend things out . A good datalogger is a nice thing to have, to bad my DFI log is so mickey mouse !! Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted February 22, 2001 Author Share Posted February 22, 2001 This datalogger was designed by a GN owner who is an engineer for one of the large Unix vendors. It logs at a phenominal rate of 18.2 frames per second and at that rate the buffer can hold 104 seconds. Drop the rate down to 9.1 and the duration doubles, etc. ------------------ Scottie 71 240GN-Z Scottie's GNZ Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted February 22, 2001 Share Posted February 22, 2001 NICE datalogger Scottie! Is he selling it an dis it just software or is there hardware components? The DFI stuff has a lousy rate of logging and to run it's fastest you give up all display. You can also only log about 6 items if I recall. The TECII up till now has been some of the best datalogging software I've seen so far but the FelPro and SpeedBrain stuff is looking pretty decent. Presently I'm looking for the WinACQ stuff that the PMS owners use for the RX7. Datalogging is an awesome tuning tool! WalMart had a very nice laptop on sale (online) for $750 a little bit ago but was sold out - I got the local brick and mortar pace to price match though. Now I just need software... http://www.walmart.com/catalog/product.gsp?cat=3951&dept=3944&product_id=932331 Quote Link to comment Share on other sites More sharing options...
clint78z Posted February 23, 2001 Share Posted February 23, 2001 The Miata guys had a real nice one for a palm pilot that does there datalogging . It was super slick and had a good sampling rate . My programming skills are limited to visual basic, so a conversion from DFI to Excel format will probably be down the road . Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted February 23, 2001 Share Posted February 23, 2001 Clint - was that using the stock computer or the MiataLink thing? I thought the stock Miata ECU was a black box still. As for the DFI - yeah dump it out, it's all comma delimited for data logging. I used to have some Excel stuff for it but it's probably lost. My biggest beef was trying to do meaningful graphs when one scale went to about 6 grand and the other was fractions of 1 - like say for the O2s. It was pretty frustrating. Quote Link to comment Share on other sites More sharing options...
clint78z Posted February 26, 2001 Share Posted February 26, 2001 I am a little fuzzy on the Miata one whether it was stock or aftermarket ECU ( think it was stock) . Anyhow the DFI situation isn't as bad as it seems, not optimal but will be very useful . Once the major tuning is done I doubt I will need more than 6 variables at a time anyway . I will logs up with RPM, O2, MAP, TPS, Air Temp, Total PW . From there a charts will be made, the key here is to plot one variable vs time and don't try and mess with scaling . Then I will put some text boxes and arrows to scroll through the graphs . It will take some time to set this up but once done will be very useful . The setup will be very simular to what Scottie has posted . Only trouble is I have to switch to Excel from DFI software . Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted February 28, 2001 Share Posted February 28, 2001 Heh, I've got DFI from a previous vehicle. Just you wait - I've seen RPM jump from say 4K at one point to 6K the next with nothing in between! The CPU in the DFI is an older slower one and it's data rate isn't super fast. It'll work but realize it has limitations. Quote Link to comment Share on other sites More sharing options...
clint78z Posted February 28, 2001 Share Posted February 28, 2001 Yes I have heard about the jump around sampling and updating . But hey it's better than a poke in the eye . Smart tuning proceedures, and some dyno time should keep me out of hot water . Quote Link to comment Share on other sites More sharing options...
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