Before and after horsepower gains
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Car: Red 1984 Z-28
Engine: 4.8 LS
Transmission: 4L60E
Axle/Gears: 3.73
Before and after horsepower gains
Was wondering if someone could give me an estimate on horsepower gains on my new exhaust I will be putting in. My car is an all stock L69 with the original L69 exhaust. It dynoed at 187 HP and 220 Lb/Ft Torque. Stock specs were 190 HP and 240 Lb/Ft Torque. Dynoed pretty decent for a 22 year old car.
My new exhaust consists of the Hooker 2055's and y-pipe, Catco High Flow cat 9118, 3 inch dynomax i-pipes and a 3 inch chambered muffler in stock location. Turndown after the muffler. Just curious how much, if any, horsepower gains I would recieve from my setup. I am going to get the car dynoed after I do it, but I just want to see some figures before hand. Thanks a lot!
My new exhaust consists of the Hooker 2055's and y-pipe, Catco High Flow cat 9118, 3 inch dynomax i-pipes and a 3 inch chambered muffler in stock location. Turndown after the muffler. Just curious how much, if any, horsepower gains I would recieve from my setup. I am going to get the car dynoed after I do it, but I just want to see some figures before hand. Thanks a lot!
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Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
wow, you dyno-ed very closed to the stock HP #, would that be RWHP though?
I'm excited to hear a real world dyno result of exhaust work. My guess is also ~25HP.
I'm excited to hear a real world dyno result of exhaust work. My guess is also ~25HP.
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Car: Red 1984 Z-28
Engine: 4.8 LS
Transmission: 4L60E
Axle/Gears: 3.73
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Engine: '85 Monte SS L69 305
Transmission: TH 200-4R
Axle/Gears: 3.23
All dyno's correct the actual measurement to a standardized one using a factor derived from athmospheric pressure, temperature, and humidity. This is in order to be able to compare readings between different places and conditions. A rear wheel dyno such as the DynoJet also often corrects the actual measured rwhp, using a guesstimate of the drivetrain losses, to present an approximation of the crankshaft horsepower. Any correction factors used I expect should be on the dyno slip I hope you received.
#6
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I put on 2055's and Y pipe. Left on the stock catback pipeing with an 80 series muffler. I gained 2 mph in the 1/4 mile.
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Car: 91 RS, 95 Z28
Engine: 305 tbi, 350 lt1
Transmission: 4l60, 4l60e
Axle/Gears: monsterous 2.73s in both
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Car: Red 1984 Z-28
Engine: 4.8 LS
Transmission: 4L60E
Axle/Gears: 3.73
All dyno's correct the actual measurement to a standardized one using a factor derived from athmospheric pressure, temperature, and humidity. This is in order to be able to compare readings between different places and conditions. A rear wheel dyno such as the DynoJet also often corrects the actual measured rwhp, using a guesstimate of the drivetrain losses, to present an approximation of the crankshaft horsepower. Any correction factors used I expect should be on the dyno slip I hope you received.
I know he has a file on the dyno's computer with my pulls, so I will see if he can email them to me to post here. Thanks for the help guys!
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Car: 88 IROC
Engine: 305 TPI w/ l98 cam
Transmission: T5 5-speed
Axle/Gears: 3.45 posi disc 9 bolt
i put eldelbrock TES headers on my 305 tpi and i noticed a difference but i highly doubt it was 20-25 HP. i would guess more around 12..
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Car: 4 Mopars total
Engine: Pentastar power
Transmission: T/F and New Process
Axle/Gears: Three 8 3/4's & one 9 1/4
He probably would if he took that Hypercrap chip out of there. LOL! (just messin around)
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Car: 88 IROC
Engine: 305 TPI w/ l98 cam
Transmission: T5 5-speed
Axle/Gears: 3.45 posi disc 9 bolt
what does ehc mean?
o know though, i have heard people complain about the hypertech chips but i paid like 30 bucks for mine b/c i got it used off this website i think. but people complain b/c it lowers your mpg and doesnt give much performance. i no longer have a computer so it doesnt matter.
btw when i ran that 15.3 i had a cracked distributor and the car had sat for 3 years and i didnt do a tune up on it so it could have probably run a high 14 with little thinks like timing and a tune up.
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Car: Red 1984 Z-28
Engine: 4.8 LS
Transmission: 4L60E
Axle/Gears: 3.73
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