[Jucostud]

went back to the track tonight. I took everything out of my trunk this time.(spare and stereo stuff). My times stayed exactly the same. 9.06. The funny thing is last week I did a 9.06 at 79mph. This week i did a 9.06 at 83mph. Every single time i would shift from 1st to 2nd, my back end would chirp and slide a little. It's like that weight helped me stick better. If i'm finishing that much faster, i would think my time would be better.

[UrbanRedneck]

less traction usually equates to a higher MPH with a slower ET. That could be the issue.

[psycho bob]

street tires and less weight means you had less traction. give and take. sometimes it hurts you more than helps you taking all the weight out. maybe not with the extra speakers and everything, but worrying about a full tank of gas and spare tire can help you get traction with your street tires.

[Stkjock]

General guideline 100lbs = .1 sec in the 1/4

however.... in your case... and many other the added weight impoves traction


also... were the temps/humidity similar? that could account for a difference as well

[Emay]

Juco Urban is correct, any sort of slippage, no matter how minor, will generally net you a higher mph with a worse ET.. eliminate the slippage and the et will improve a tenth or 2.. What was the 60ft on that 9.0 pass? That may tell a story in itself..

Are you planning on running a radial at any point?

Also, like stkjock asked - what were the temps and humidity like, converting your 1/8th your 1/4 would be about a 14.2 which tells me the conditions were not the most favorable..

[Jucostud]

Originally Posted by Emay Juco Urban is correct, any sort of slippage, no matter how minor, will generally net you a higher mph with a worse ET.. eliminate the slippage and the et will improve a tenth or 2.. What was the 60ft on that 9.0 pass? That may tell a story in itself.. Are you planning on running a radial at any point? Also, like stkjock asked - what were the temps and humidity like, converting your 1/8th your 1/4 would be about a 14.2 which tells me the conditions were not the most favorable..

It was hot. don't know for sure what the temps were like, but i was sweating my ass off. I could only get a 2.24 60ft last night. I just couldn't grip. This wasn't an issue before. I still beat an evo and a 5.0 though

[07stanggt]

i did the same thing takeing it all out of my trunk and had the same issue. it could have been the track as well. there are nights i can keep it to the floor and hit second and it just barks the tires and goes, there are nights it will go sideways doing that.

[Jucostud]

the last run of the night i got a 10.15. They shut the track down to one lane and were just trying to get everybody out of the stagging lanes. The was a big oil spill in the left lane. They stopped preping the track because they were just trying to get everybody out... I launched and spun all the way through first and part of second and then bogged down. Still hit 77mph

[Jucostud]

typicaly what should my et be with a speed of 83mph? If i'm hooking?

[07stanggt]

Originally Posted by Jucostud typicaly what should my et be with a speed of 83mph? If i'm hooking?

I dont know. i got a slip with 85.27 and a et of 8.7 i got one run with a 2.1 60 84.71 and a 8.857. looking at couple runs against a freind of mine he had a 2.1 60 at 83.73 with a 8.826. he has 3.73s on stock 18s and nittos cai and tune. im usaually at about 87 mph in the low 8s in the 1/8.

[07stanggt]

remember what those other guys said though, if your hooking....then you might have a lower et with a slower mph, if you dead hook you may bog some, your rpms will be down off the line so maybe a lower mph at the 1/8. if you spin some it keeps those rpms up and the engine makeing more hp so you get a fastet mph with a lower et. make sense?

[BLACJAC]

Originally Posted by Jucostud typicaly what should my et be with a speed of 83mph? If i'm hooking?

U MIGHT HAVE HAD TOO HOT OF AN ENGINE BY THEN, U NEED TO DO THE SAME IN THE WINTER DOWN UNDER WHERE U ARE , THAT WILL DROP UR ET"S

[07stanggt]

Yea the cool air in the fall will make some power for you. but as for the two hot of an engine theory, dont get to worried about that. if it affects your car it affects you car you will know that quick. I can tell that i have hot lapped my car 5 runs in a row and lost nothing off the MPH. Also some of my fastest runs with the highest MPH have been as soon as i got there right after a 1.5 hour drive, vice versa, i have made a few runs, let my car sit for two hours at which point sun was down, made two more runs and didnt pick up 1 mph in the 1/4 on a totally cooled down car, even after the fluids warmed up for the second lap, nothing. the 1/8 is all in the 60 foot time.

[coolhandluke]

Is anyone seeing any drop in ET's w/ ethanol blended fuel? I know that ethanol has been used in several states for the last 10 -15 years but it seems to be a recent occurrence here in OK. IMO...I seem to be able to tell a substantial power difference between 10% and alcohol free.

[Emay]

That and a drop in MPG.. seeing an 22% drop in my avalanche on E85.. Far better performance overall - snappier throttle response but at a cost of standing in front of the fuggin pump far more often..

[coolhandluke]

Originally Posted by Emay That and a drop in MPG.. seeing an 22% drop in my avalanche on E85.. Far better performance overall - snappier throttle response but at a cost of standing in front of the fuggin pump far more often..

So you actually have more power w/ ethanol due to higher octane? I could swear that I have far less power and loose about 40-50 miles on a tank w/ an ethanol blend.

[EfylSetaf]

Originally Posted by coolhandluke So you actually have more power w/ ethanol due to higher octane? I could swear that I have far less power and loose about 40-50 miles on a tank w/ an ethanol blend.

Emay's talking about the E85 on a vehicle tuned from the factory for it. That's 85% ethanol, isn't it? It does give better performance -- burns cleaner? -- than straight gasoline, but needs more of the fuel to create the same amount of energy in each explosion.

You shouldn't see a performance difference between the 10% ethanol blends vs. 100% gasoline unless you're tuned to take advantage of it, otherwise you get the same air / fuel mixture either way -- computer doesn't know there's a difference. Just like we don't see a difference in our Mustangs between 87 and 93 octane gas without the aftermarket tune.

The 10% ethanol produces less energy than the 10% gasoline it replaces in the blend which is why you see a MPG hit.

[coolhandluke]

Originally Posted by EfylSetaf Emay's talking about the E85 on a vehicle tuned from the factory for it. That's 85% ethanol, isn't it? It does give better performance -- burns cleaner? -- than straight gasoline, but needs more of the fuel to create the same amount of energy in each explosion. You shouldn't see a performance difference between the 10% ethanol blends vs. 100% gasoline unless you're tuned to take advantage of it, otherwise you get the same air / fuel mixture either way -- computer doesn't know there's a difference. Just like we don't see a difference in our Mustangs between 87 and 93 octane gas without the aftermarket tune. The 10% ethanol produces less energy than the 10% gasoline it replaces in the blend which is why you see a MPG hit.

OK ...I was assuming that it would make less power as well since it takes more ethanol (I think 2x's as much) to equal the combustion power of gasoline. If your air / fuel mixture remains constant I would think that would mean that you would make less power as well. I think that I confused myself somewhere...

[06RedfireGT]

Ethanol has a higher octane than regular gasoline, and it burns cleaners, but there is less energy potential per unit of ethanol than there is in gasoline, therefore more has to be burned to get the same result as gasoline, which is why fuel mileage takes a hit.

[coolhandluke]

Originally Posted by 06RedfireGT Ethanol has a higher octane than regular gasoline, and it burns cleaners, but there is less energy potential per unit of ethanol than there is in gasoline, therefore more has to be burned to get the same result as gasoline, which is why fuel mileage takes a hit.

So why is there not a power loss like I was assuming? I doesn't make sense to me that ethanol has half the energy potential per unit and still let an engine produce the same amount of power. I understand that the mpg will suffer due to having to use a larger amount of fuel to make power, but the air/fuel volume should still be the same during the combustion cycle regardless of the fuel type right? If so, I would think that you would be producing less power.

I apologize in advance for being a dumbass...