KiD-ViD Posted July 11, 2005 Share Posted July 11, 2005 Ok, a friend of mine is trying to tell me that now that he has installed iridium plugs he is seeing less rpm at a fixed speed than before. I am telling him this is impossible because engine speed + gearing = actual speed. There is no way to change the mph you are going at a certain rpm other than changing the gear ratio or by changing the wheel/tire size. Although I havnt posted in a while and do not own a Z, I know this forum to be the most technicly saavy and knowledgable I have ever come accross. Anyway, here is the aim conversation. dxpong: I get less RPM all around at the usual speeds dxpong: like at 5th gear going 70MPH, i'm at 3k RPM, but after the plug change I was running at 2,750 RPM drumlightning5: thats physically impossible dxpong: nah drumlightning5: yes, actually it is dxpong: hotter spark = less RPM drumlightning5: no sorry drumlightning5: its all gearing dxpong: yes, and efficientcy drumlightning5: no drumlightning5: hold on a second dxpong: I'll link you dxpong: http://www.densoiridium.com/tunerstales.php drumlightning5: your engine is spinning the flywheel at 3000 rpm which in turn spins the tranny whichs spins driveshaft to diff witch has another gear reduction which spins the wheels drumlightning5: the engine speed is what determines speed drumlightning5: efficency has nothing to do with it Quote Link to comment Share on other sites More sharing options...
datsunlover Posted July 11, 2005 Share Posted July 11, 2005 Might I ask how old is this 'friend' of yours? (If this was one of my friends, I would not be so kind.. ) I've heard someone say something similar.. I laughed in his face and made sure everyone else in the parking lot knew what he was trying to say. Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted July 11, 2005 Share Posted July 11, 2005 Maybe his old plugs were bad and caused some noise to get into his tach, raising the displayed rpm.... Quote Link to comment Share on other sites More sharing options...
KiD-ViD Posted July 11, 2005 Author Share Posted July 11, 2005 Maybe his old plugs were bad and caused some noise to get into his tach, raising the displayed rpm.... ooo that is possible, but I think in this case unlikely. Oh and if anyone cares this is on a Z32 and the guy is in his mid 20's. I also recieved this later on... dxpong: I talked it over with a professor at my uni dxpong: due to an increase in HP/Torque is what's allowing the car to run at a lower RPM to KEEP the car at speed Quote Link to comment Share on other sites More sharing options...
2126 Posted July 11, 2005 Share Posted July 11, 2005 Just let the kid live with his lack of understanding. Duuuuh! If he can't figure it out on his own, you will certainly never convince this genius!!! Besides, it's all black magic anyway....isn't it? Quote Link to comment Share on other sites More sharing options...
Phyxius Posted July 12, 2005 Share Posted July 12, 2005 i could see this being somewhat possible with an automatic...because of the converter...but not a manual... Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted July 12, 2005 Share Posted July 12, 2005 i could see this being somewhat possible with an automatic...because of the converter...but not a manual...Yup, tell him to fix his torque converter. Quote Link to comment Share on other sites More sharing options...
Tim240z Posted July 12, 2005 Share Posted July 12, 2005 .....or tell him the air in his tires has moved from the bottom of the tire to the top of the tire Quote Link to comment Share on other sites More sharing options...
datsunlover Posted July 12, 2005 Share Posted July 12, 2005 Actually, his back tires might be going forward.. veeeery bad.. might be causing the guage's to mis read... Quote Link to comment Share on other sites More sharing options...
Z-TARD Posted July 12, 2005 Share Posted July 12, 2005 Did he check his dilithium crystals for proper magnetic flux readings? That should fix it right up..... Mike Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted July 12, 2005 Share Posted July 12, 2005 Duuuuuuddddddde, your just not tripping on the right stuff man! With the killer stuff he's on man, everything that you thought was real ain't real anymore. Go ahead, try what he's on, I'm sure it'll change your prospective on everything! Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted July 12, 2005 Share Posted July 12, 2005 That is a 3 word conversation: "You're a moron" Quote Link to comment Share on other sites More sharing options...
GabeRoc Posted July 12, 2005 Share Posted July 12, 2005 you know, i have a set of light weight lug nuts that will reduce the moment of inertia of his wheel/tires. should be good for about 50 RPM at 70MPH. i'll let them go for a song. --gabe Quote Link to comment Share on other sites More sharing options...
EZ-E Posted July 12, 2005 Share Posted July 12, 2005 That is a laugh, but I will say this, NGK iridiums have helped a stumble that I have had for ages at idle. It is not totally gone. It did not however change the rpm band. LOL Quote Link to comment Share on other sites More sharing options...
Sumo Posted July 12, 2005 Share Posted July 12, 2005 Maybe some of the irridium got in his blood stream and is making him hallucinate. Quote Link to comment Share on other sites More sharing options...
strotter Posted July 12, 2005 Share Posted July 12, 2005 OK now, wait a minute, there may be something to this... seriously. Do Z32s have lock-up torque converters? If so, I'm thinking that if he's seeing lower TPS and MAP at any given RPM, his converter might be locking up at lower speeds thereby giving him lower RPM at those speeds. Or, of course, he's 'tarded. Quote Link to comment Share on other sites More sharing options...
KiD-ViD Posted July 12, 2005 Author Share Posted July 12, 2005 OK now' date=' wait a minute, there may be something to this... seriously. Do Z32s have lock-up torque converters? If so, I'm thinking that if he's seeing lower TPS and MAP at any given RPM, his converter might be locking up at lower speeds thereby giving him lower RPM at those speeds. Or, of course, he's 'tarded.[/quote'] Too bad his car is a manual so I guess we will go with option #2. Strotter, Your car is the yellow v8z right? If so I have seen you around town a few times and it is a beautiful car I must say. Quote Link to comment Share on other sites More sharing options...
TheNeedForZ Posted July 13, 2005 Share Posted July 13, 2005 Maybe the tires got bigger. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted July 13, 2005 Share Posted July 13, 2005 Maybe his head got bigger, resulting in more uplift, which put less load on the tires effectively increasing their diameter. That would do it. Quote Link to comment Share on other sites More sharing options...
Guest viparz Posted January 8, 2007 Share Posted January 8, 2007 Can I ask you guys why a car requires more rpm to travel at the same speed when going up a hill? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.