Me and Maverick Man did some time only runs yesterday and Derrick is now faster than me. Unfortunately for him he didn't go faster, but I went .7 sec slower. I changed over to the 9" rear with 4.30 gears from the old stock 8" with 3.40's. I also had the new Prostar rims all around and new front skinnies, so I thought I was going to do much better. I don't know why I slowed so bad but I'm thinking maybe my converter has way too low of a stall now. It could have stalled higher with the old 3.40 gears. Still 0.7 sec. seems like a lot. Also, could have been that my alternator pulley came off on every run. Also, could have been the 15 degrees temperature difference from last time. You guys have any suggestions?
excuses! but i'll take what i can get but i actually ran faster this time.. low 7.73 vs the 7.79 (but i think i gotta look at the vid again) but stil not as fast as the low 7.60 it use to be. and with all the work i did too ! i guess we both need to go by the old saying.. if it ain't broke don't fix it! along with erick i have problems still too! but mine is STILL Smoking tire! i'll post a vid of it later when i can get some more hard drive space!
.7 is a lot for just weather. generally each degree is worth .01 (approx). first, the 9" weighs more than the 8". i've heard 30-40 pounds. going up numerically in rear gear ratio reduces your stall in the converter. but still sounds like a lot to slow up.
my question is did your car leave at the same temperature. i know that if mine is up by 10 degrees i'm not gonna run the number. also when i changed from the 4500 stall to the 3500 stall convertor i lost almost .4.
You might try comparing time slips from your previos best Erick and see exactly where your losing it, this can tell you alot unless its through the entire pass, also was the humidity level higher in the fast pass. I don't know what you were running before the prostars but if they were a street mag I'd say you made up for the weight gain the 9" gave you. Just throwing some things out there...7 tenths is a huge loss and I'd guess it centers around one particular thing vs. a bunch of little things...you'll get it back..keep us posted. Derrick is never gonna let you forget this one
the altenator pulley kept coming off? what up wid dat. are you taching out faster in each gear than before? maybe your not staying in the right power curve long enough with the new gearing? Just a thought. youll figure it out. maverick man, you just need to figure out your traction issue and youll be back at the old times or faster. you guys need to come to the reno show and race me so i can see what fast mavs look like on the strip
Sorry, meant to say my alternator belt came off...I got a new underdrive pulley and had to get a longer belt. I'm guessing what slowed me down was the gear/converter combo . Maverick Man needs to get some traction. Me and his dad think it's just the driver, LOL. Is there a link to the Reno show info? I've heard about it, but don't remember seeing any info about it.
any wheel spin? more than before? was mph the same? yes, compare it to an old time slip & see where the incrementals changed.
One thing to consider is that you should be shifting a lot sooner now than before (with taller gears). Could it be your are shifting too LATE? Do you have a shift light? .7XX is a lot to lose. I hope you find out just what it is and get it back down to where you were before at least.
My MPH went down from 97 to 88, 60' times went up from 1.67 to 1.78. I have a shift light and upped my shift point to 6800 from 6500 (my engines power band is supposed to be 5500-7500). It didn't feel like my slicks slipped but maybe its harder to feel with 4.30 gears? I'll have to do some more testing with someone watching my wheels at the start. Thanks everyone for the help.
Eric, I wouldn't be surprised if you are shifting out too late now - especially since you said you 'upped' the shift point. I remember when I went from a short gear to a taller gear. My engine reached it's peak rpm SO much quicker than before. I actually had to LOWER my shift light point to accomodate for the quick "rap" of the engine's rpm. By the time we react to a shift light, I would think .2 seconds have passed (at least). By the time the tranny does it's thing, the engine's rpm is way out of the power band (in my case). Lowering the shift light kept the engine in it 'usable' torque range. I dunno what all is going on with your car, but lowering the shift point might be something to consider. Best of luck with it. Please let us know what the deal was after you get it figured out.
something is off. is the rear gear too much and you are going past the power zone of the engine? mph is a reflection of hp vs vehicle weight. if you dont change the hp of the engine, just the application of the hp (gears, converter, etc), then mph stays about the same. unless you have too much gear or are shifting past the best power curve. that would make the engine "see" less hp.
I was thinking the opposite is happening...my stall is now much lower so I am not getting up into my power band of the engine, thereby losing horsepower and torque. Is it possible that steeper gears could lower the stall enough to cause this? My engine should need the higher rpms to make the most power (like shifting at 7500), but I'll try shifting a little earlier to see what happens.
