300 rwhp?
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Launching!
Joined: Apr 2007
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300 rwhp? I recently had my 1999 z28 dynoed. It is pushing only 300 hp to the rear wheels. It has a 4L60E tranny. I thought these LS1's were under-rated at 315hp? Why is mine sooo weak? Please help!
On The Tree
Joined: Apr 2007
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From: Connecticut
Someone else can probably go into more detail than me, and I'm sure they will, but for 99 they are underated at 305 at the fly wheel, where it's more like 345 in reality. So if your car is stock, 300 is a good number to the rear wheels.
Last edited by Cruz28; Jul 30, 2007 at 07:36 PM.
TECH Senior Member
Joined: Jan 2004
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From: St.Charles MO
Originally Posted by texas99Z28
I recently had my 1999 z28 dynoed. It is pushing only 300 hp to the rear wheels. It has a 4L60E tranny. I thought these LS1's were under-rated at 315hp? Why is mine sooo weak? Please help!
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Originally Posted by texas99Z28
My nephews 2002 Formula pushed 376 rwhp with a k@n filter and Lm exhaust, so I was hoping for 330 to 340 hp
you wont gain 30-40 hp with just a cat back and K&N filter 
Originally Posted by texas99Z28
I'm thinking of putting SLP Loudmouth on it and 3.73 gears next. Good idea?
The first REAL performance mod to an automatic-equipped LS1 should be a torque converter & aux trans cooler...The converter will need some adjustments made to the PCM..So go ahead & find a good tuner ahead of time...Unless you are running 2.73's,gears aren't as much of a priority.
There are sponsors to the right who can assist you further.
>>>>>>>>>
I'm a big Thunderracing /Texas speed fan.
Originally Posted by texas99Z28
My nephews 2002 Formula pushed 376 rwhp with a k@n filter and Lm exhaust, so I was hoping for 330 to 340 hp
Teching In
Joined: Jul 2007
Posts: 48
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From: Cypress, TX
Originally Posted by texas99Z28
My nephews 2002 Formula pushed 376 rwhp with a k@n filter and Lm exhaust, so I was hoping for 330 to 340 hp
