IS THERE A NEED?
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From: New York City
Originally Posted by willwren
I checked on the Gears also, and you're right on the 2.93'* for stock GTP'*. My bad on that one.
I'll write yours off to the lighter car making it less noticable.
Most people don't mess with a 3" dp until they have rockers or a cam, and headers as well. I don't think you're going to gain anything noticable with a 3" dp on PEM'*.
I'll write yours off to the lighter car making it less noticable.
Most people don't mess with a 3" dp until they have rockers or a cam, and headers as well. I don't think you're going to gain anything noticable with a 3" dp on PEM'*.
Originally Posted by Foghorn
Just to debunk one notion going around;
The 97 to 99 SSEi is about equal in weight to a 97 to 03 GTP 4 door
I've been on a scale with my car and a buddies 1999 GTP 4 door on the same day, same scale and they were within 20 Lbs of each other.
The 97 to 99 SSEi is about equal in weight to a 97 to 03 GTP 4 door
I've been on a scale with my car and a buddies 1999 GTP 4 door on the same day, same scale and they were within 20 Lbs of each other.
Many people on other w-Body forums have had good expierences with the PEMs & 3" dp combo. (sorry for the spelling)
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Originally Posted by willwren
That'* because the stock downpipe on the GTP has a restrictive U-bend in it. You can't make that comparison.
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The U-bend IS the downpipe on a Grand Prix.
http://www.zzperformance.com/grand_p...=504&catid=110
They gain mostly from the U-bend delete. That'* the point I'm trying to make. It'* a restriction, far more than a stock DP on a Bonneville, which has no bend.
http://www.zzperformance.com/grand_p...=504&catid=110
They gain mostly from the U-bend delete. That'* the point I'm trying to make. It'* a restriction, far more than a stock DP on a Bonneville, which has no bend.
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From: New York City
Originally Posted by willwren
The U-bend IS the downpipe on a Grand Prix.
http://www.zzperformance.com/grand_p...=504&catid=110
They gain mostly from the U-bend delete. That'* the point I'm trying to make. It'* a restriction, far more than a stock DP on a Bonneville, which has no bend.
http://www.zzperformance.com/grand_p...=504&catid=110
They gain mostly from the U-bend delete. That'* the point I'm trying to make. It'* a restriction, far more than a stock DP on a Bonneville, which has no bend.
Originally Posted by ZZP
Stock downpipes are double-walled tubing with an inside diameter of just over two inches. Following the restrictive downpipe section, the stock unit subjects the exhaust gases to the choking effects of the catalytic converter. After the cat, it flattens out into a section dubbed the infamous "U-Bend
They still see a noticeable difference with the 3" dp . With the U-bend gone. But like I said they wouldn't do the DP without the U-bend Deleted. I know that the bonneville has a less restrictive exhaust but the poster asked if there was room for improvement on the exhaust, the downpipe can stand some improvement.
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From: New York City
Originally Posted by chadow427
Originally Posted by willwren
Explain billboost'* loss of low-end with the same mods and a 3" dp?
Lets see what he says. :P
