LS Power!! Twin 76mm Turbo 4.8L 1200HP & still going!!
07-21-2011, 06:23 PM
#51
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I guess toss was a bad word to use. I meant in some way hurt a rod other then a rod bolt failure.
Regardless this was an awesome build by hot rod. I'd love to see what it would take to break it and if you had aftermarket pistons and rods in there what the block and crank could take.
Regardless this was an awesome build by hot rod. I'd love to see what it would take to break it and if you had aftermarket pistons and rods in there what the block and crank could take.
07-21-2011, 06:28 PM
#52
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Also, it takes 1260 lb/ft of torque to make 1200hp at 5000rpm. It takes 840 lb/ft to make 1200hp at 7500rpm. Less torque means less cylinder pressure means the rods are less likely to buckle. I 100% agree with LS1FREEK.
07-21-2011, 11:12 PM
#53
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The injectors can be bandaided somewhat with high fuel pressure like mentioned, and the lesser load of a engine dyno might contribute to the smaller injectors being acceptable some.. I see the mentioned bigger fuel rails, any mention of the rest of the fuel setup? Does make it a little hard to swallow seeing just the 75s mentioned.
Now the n/a argument, 450n/a on an engine dyno would probably be around 370ish thru a 60e auto. So that means could a 4.8 with 7/8 headers, fast intake, good heads, and no accessories at all be able to peak @7k rpm with that cam and make 370rwhp. Imo yes it could be done..
I think everybody is overlooking what i would call a pretty impressive top end with that intake and heads. Everything ive seen with a fast and boost has shown really good numbers and performs really well, this is no different..
Do this on a completely stock 4.8 with no upgrades and i think they barely break the 1k mark..?
Now the n/a argument, 450n/a on an engine dyno would probably be around 370ish thru a 60e auto. So that means could a 4.8 with 7/8 headers, fast intake, good heads, and no accessories at all be able to peak @7k rpm with that cam and make 370rwhp. Imo yes it could be done..
I think everybody is overlooking what i would call a pretty impressive top end with that intake and heads. Everything ive seen with a fast and boost has shown really good numbers and performs really well, this is no different..
Do this on a completely stock 4.8 with no upgrades and i think they barely break the 1k mark..?
You don't think a heads, big cam, Fast intake, large primary headers, no accessories, electric water pump, 4.8 can put down 450? Take 20% away for drivetrain losses and you would see ~360 rwhp in a vehicle. Seems legit to me...
As for the injectors, I don't know...
Edit: skolman beat me to it, lol
As for the injectors, I don't know...
Edit: skolman beat me to it, lol
The numbers ARE inflated N/A and boost, but impressive none the less.
07-22-2011, 12:00 AM
#54
The fuel injectors come down to fuel pressure. Those 75lb's quickly become 100lb+. I run my 80's at 94 and would go higher if I had a stronger pump setup to support it. I would say they have more then enough pump suppling pressure/volume at the test stand.
As to the power, here's another one, stock crank and rods. It does have pistons though, ended up making 1342HP/928TQ at 7500rpms.
‪1200hp 339 destroked lsx376‬‏ - YouTube
This is a 4.8L rod on the left, 5.3 mid, lq9 on end. Sure hell doesn't look like a 1300HP rod. I would want to be wrapped in armor if I pushed my truck to those levels for a 1/4 pass.
As to the power, here's another one, stock crank and rods. It does have pistons though, ended up making 1342HP/928TQ at 7500rpms.
‪1200hp 339 destroked lsx376‬‏ - YouTube
This is a 4.8L rod on the left, 5.3 mid, lq9 on end. Sure hell doesn't look like a 1300HP rod. I would want to be wrapped in armor if I pushed my truck to those levels for a 1/4 pass.
07-22-2011, 07:30 AM
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This article was awesome! Gives me hope for my 4.8...Save the money I was gonna use for a engine swap for a t56.....
Just curious....does anyone know if the reason this test got such interesting results is because they used a turbocharger set up instead of a magnacharger?
Just curious....does anyone know if the reason this test got such interesting results is because they used a turbocharger set up instead of a magnacharger?
Last edited by 1quickRST; 07-22-2011 at 08:10 AM.
07-22-2011, 10:12 AM
#56
This article was awesome! Gives me hope for my 4.8...Save the money I was gonna use for a engine swap for a t56.....
Just curious....does anyone know if the reason this test got such interesting results is because they used a turbocharger set up instead of a magnacharger?
Just curious....does anyone know if the reason this test got such interesting results is because they used a turbocharger set up instead of a magnacharger?
07-22-2011, 11:56 AM
#57
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Don't get me wrong I think the #'s are alittle inflated but doing some figuring on injector sizing it is possible.
Injectors are rated at 43 psi most of the time. That would mean 75 lbs injectors at the common 58 psi of an LS motor would bring the total flow to 87 lb injectors. Then a 8 cyl engine making 1200 hp at 7500 rpm would have a duty cycle of 74%. Delivering 516 lbs/hr of fuel.
Injectors are rated at 43 psi most of the time. That would mean 75 lbs injectors at the common 58 psi of an LS motor would bring the total flow to 87 lb injectors. Then a 8 cyl engine making 1200 hp at 7500 rpm would have a duty cycle of 74%. Delivering 516 lbs/hr of fuel.
07-22-2011, 01:24 PM
#58
Injectors are rated at 43 psi most of the time. That would mean 75 lbs injectors at the common 58 psi of an LS motor would bring the total flow to 87 lb injectors. Then a 8 cyl engine making 1200 hp at 7500 rpm would have a duty cycle of 74%. Delivering 516 lbs/hr of fuel.
07-22-2011, 01:58 PM
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Don't get me wrong I think the #'s are alittle inflated but doing some figuring on injector sizing it is possible.
Injectors are rated at 43 psi most of the time. That would mean 75 lbs injectors at the common 58 psi of an LS motor would bring the total flow to 87 lb injectors. Then a 8 cyl engine making 1200 hp at 7500 rpm would have a duty cycle of 74%. Delivering 516 lbs/hr of fuel.
Injectors are rated at 43 psi most of the time. That would mean 75 lbs injectors at the common 58 psi of an LS motor would bring the total flow to 87 lb injectors. Then a 8 cyl engine making 1200 hp at 7500 rpm would have a duty cycle of 74%. Delivering 516 lbs/hr of fuel.
