Lost some top end??Any ideas?
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Joined: Feb 2004
Posts: 362
From: Portland, OR
Lost some top end??Any ideas?
Well 2 months ago i was turning 12.75@108-109MPH with my 16" street tires. The only thing i changed is, i want to 16" M/T et streets and I have my 18" c-5 wheels up front. Now im turning 13.10 @ 104-105. Could the new tires and wheels have hurt me that much? Or is there something else i should look at?
Holla Adam
Holla Adam
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Joined: Nov 2001
Posts: 2,985
From: In a house by the bay
Re: Lost some top end??Any ideas?
So you went from a 16" tire set (radials all around) running 12.75 to 13.1 using a drag-slick 18" front setup?
I don't think you'd lose that much... plus you're now launching on a slick! What do the 60' times look like?
I'd venture it's something mechanical... maybe valvesprings. Have you performed a compresion or leakdown test?
-Mindgame
I don't think you'd lose that much... plus you're now launching on a slick! What do the 60' times look like?
I'd venture it's something mechanical... maybe valvesprings. Have you performed a compresion or leakdown test?
-Mindgame
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Joined: Aug 2003
Posts: 659
From: Orlando, Florida
Re: Lost some top end??Any ideas?
What size are the ET streets? Is your car an A4 or M6? Am I correct in guessing its an auto?
Those ET streets are a lot of tire to turn with stock gears, and frankly they just don't work as well. My dad has a set of 26 X 10.5 ET streets for his SS and I tried running on them on a few runs...the best I could pull off was like a 12.90 @ 108 or something like that. I remember scratching my head afterwards as well cause I couldn't figure out what the problem is. I really wouldn't go to a larger tire until you have the gears or power to really turn 'em...it just makes the car accelerate that much slower.
Maybe I'm way off on this, but I'm pretty sure thats where your problem lies...that and I'm sure the weather is a little warmer now than it was before.
Just my $0.02
-Dan
Those ET streets are a lot of tire to turn with stock gears, and frankly they just don't work as well. My dad has a set of 26 X 10.5 ET streets for his SS and I tried running on them on a few runs...the best I could pull off was like a 12.90 @ 108 or something like that. I remember scratching my head afterwards as well cause I couldn't figure out what the problem is. I really wouldn't go to a larger tire until you have the gears or power to really turn 'em...it just makes the car accelerate that much slower.
Maybe I'm way off on this, but I'm pretty sure thats where your problem lies...that and I'm sure the weather is a little warmer now than it was before.
Just my $0.02
-Dan
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Joined: Aug 2003
Posts: 659
From: Orlando, Florida
Re: Lost some top end??Any ideas?
A converter will definitely help your cause...those tires really are overkill for your current set up. Either get some gears, a converter, or more power....my vote is for more power. 
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Joined: Jul 1998
Posts: 6,247
From: Charlotte,MI USA
Re: Lost some top end??Any ideas?
Originally Posted by V6toZ28
Look ... you went from 16" wheels to 18" wheels up front ... Think in terms of bigger and heavier front wheels.
At your power level ET streets didn't slow me down at all but I had the converter in at the same time as the tires.
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