Stock 4.8 802RWHP but valve float now
03-17-2014, 08:41 PM
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Stock 4.8 802RWHP but valve float now Stock 4.8 engine
26 PSI on C16 made 802 RWHP but now I cant rev this thing past 6000 RPM. I guess thats right around 1000 hp at the crank through my TH400 and PTC converter.
My goal was to run faster than my old Turbo V6 with a stock Ls1 4.8. I almost did. The 4.8 finally went 6.5 @ 23 psi but the old v6 went 6.455. Although the 4.8 went 107 mph in the 1/8 and the V6 only went 105 so it looks like Im making more power anyways.
I ordered valve springs, trunion kit and push rods so I can rev it past 6k at 26 psi.
My question is has anyone DONE a turbo 4.8 if so what cam did you use.
26 PSI on C16 made 802 RWHP but now I cant rev this thing past 6000 RPM. I guess thats right around 1000 hp at the crank through my TH400 and PTC converter.
My goal was to run faster than my old Turbo V6 with a stock Ls1 4.8. I almost did. The 4.8 finally went 6.5 @ 23 psi but the old v6 went 6.455. Although the 4.8 went 107 mph in the 1/8 and the V6 only went 105 so it looks like Im making more power anyways.
I ordered valve springs, trunion kit and push rods so I can rev it past 6k at 26 psi.
My question is has anyone DONE a turbo 4.8 if so what cam did you use.
03-17-2014, 08:49 PM
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Stock 4.8 engine
26 PSI on C16 made 802 RWHP but now I cant rev this thing past 6000 RPM. I guess thats right around 1000 hp at the crank through my TH400 and PTC converter.
My goal was to run faster than my old Turbo V6 with a stock Ls1 4.8. I almost did. The 4.8 finally went 6.5 @ 23 psi but the old v6 went 6.455. Although the 4.8 went 107 mph in the 1/8 and the V6 only went 105 so it looks like Im making more power anyways.
I ordered valve springs, trunion kit and push rods so I can rev it past 6k at 26 psi.
My question is has anyone DONE a turbo 4.8 if so what cam did you use.
26 PSI on C16 made 802 RWHP but now I cant rev this thing past 6000 RPM. I guess thats right around 1000 hp at the crank through my TH400 and PTC converter.
My goal was to run faster than my old Turbo V6 with a stock Ls1 4.8. I almost did. The 4.8 finally went 6.5 @ 23 psi but the old v6 went 6.455. Although the 4.8 went 107 mph in the 1/8 and the V6 only went 105 so it looks like Im making more power anyways.
I ordered valve springs, trunion kit and push rods so I can rev it past 6k at 26 psi.
My question is has anyone DONE a turbo 4.8 if so what cam did you use.
03-17-2014, 09:05 PM
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Yeah your right. my pass at 26 PSI, 802 rwhp would only rev to 6000 and my converter is too loose so the converter was trying to catch up to the motor but slipping. My data log showed 6000 rpm steady like a rev limiter. Too much intake manifold pressure causing valve float. It went slower at 26 psi 6.8 @ 104 mph. At 23 psi it would rev to 6800 and the converter was not slipping at much. I leave off the brake @ 5000 but can stall upto 5500.
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03-17-2014, 09:53 PM
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03-17-2014, 10:04 PM
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03-17-2014, 10:13 PM
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Great turbo for the money. This is my first LS motor and I am very happy with my swap from the Buick turbo v6. I get alot of Buick haters but you cant go wrong with a craigs list 300 dollar 4.8. And I had it delivered to my shop too!!!
03-17-2014, 11:53 PM
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yep everything in the long block is completely stock. Head bolts, gaskets, cam springs, ect. Everthing... Only edelbrock intake manifold and stainless headers I built. with a s475 turbo. And my tune.
03-17-2014, 11:58 PM
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I do have a comp behive spring kit ON THE WAY and the trunion kit with comp push rods. I will install them this week and hopefully next Sunday make some passes @ 26 psi PLUS now that I know what kinda timing this thing likes on C16
03-18-2014, 06:28 AM
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i would use the Brian Tooley dual valvesprings, or PAC springs before i would use the comp cams behives (they tend to break faster than stock springs)