Is a 550rwtq LS7 possible?
With a LS7 block and ~11.25 CR ported LS3 heads and LS3 intake you will get close to 550 rw tq and hp. (with the right cam). The LS3 heads seem to limit peak hp a bit but the hp/tq # come out about the same. LS7 heads with LS7 intake will make more hp but will not be as "square" re hp/tq.
So 550/550 rw is not difficult but will likely be more than you can use in 1st, 2nd and while cornering in 3rd gear. (AX)
The same engine with intake/carb will make much more hp but the hp gains are almost equal to torque loss.
So 550/550 rw is not difficult but will likely be more than you can use in 1st, 2nd and while cornering in 3rd gear. (AX)
The same engine with intake/carb will make much more hp but the hp gains are almost equal to torque loss.
I see a lot of tire kickers, but only one graph? This car had a lot more to it than just a heads/cam package. Its the entire combo... Not so much cam, REALLY good heads, good rotating assembly, and every bolt on that could be bolted on...
And no, it isnt easy like everyone says. 530 is very doable around here, 550 is not.
Louis
On The Tree
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From: Brampton, Ontario
It's getting harder and harder to find an honest dyno around here. Too many people believing the BS numbers that are thrown out here so easily and the nut hangers piling on but I guess that's what sells. 550 on an honest dyno IS going to be hard and will take a very well designed high compression 12+:1 engine. It's probably not going to be something you'll drive around on the street.
A wise man once said, 'believe half of what you see, and even less of what you hear, and even less of what you read.
Might be a challenge with an LS7 block. Several have tired and succeeded somewhat until the cylinder wall has blown out.
a C5R block, Warhawk or Dart Billet block would be a great starting place for that kind of power.
The C5R and LS7r blocks ( Corvette racing) run ~ 580 BHP and ~640 LBFT ( FLTQ)
a C5R block, Warhawk or Dart Billet block would be a great starting place for that kind of power.
The C5R and LS7r blocks ( Corvette racing) run ~ 580 BHP and ~640 LBFT ( FLTQ)
BUT.....a block isnt what makes power. Using one of those blocks is a complete waste of money for just 550 RWTQ.
With a LS7 block and ~11.25 CR ported LS3 heads and LS3 intake you will get close to 550 rw tq and hp. (with the right cam). The LS3 heads seem to limit peak hp a bit but the hp/tq # come out about the same. LS7 heads with LS7 intake will make more hp but will not be as "square" re hp/tq.
So 550/550 rw is not difficult but will likely be more than you can use in 1st, 2nd and while cornering in 3rd gear. (AX)
The same engine with intake/carb will make much more hp but the hp gains are almost equal to torque loss.
So 550/550 rw is not difficult but will likely be more than you can use in 1st, 2nd and while cornering in 3rd gear. (AX)
The same engine with intake/carb will make much more hp but the hp gains are almost equal to torque loss.
hum...I have 440 rwtq and use ported milled LS3 heads on top of a 416 with a 232/246 cam. where in the world does 550 come from?
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From: Vancouver,[KITSILANO].B.C. Canada *WestCoast*
The dyno is for a PM forged LS7 with ported LS3 heads and stock LS3 intake and a conservative cam built for this limited street/RR track day car.
This particular car was pulling several car lengths on the "factory" ZR1s a few weeks ago @ Road America.
The dyno is a SuperFlow eddy current which is a dream to VE tune on. I have been able to tune out much of the ~3k torque stall. It does correlate numbers closely with a Dynojet. These numbers are typical of our similar builds which are certainly not dyno queens.
My car is similar except for the stroke and makes a bit more torque commensurate with the extra cubes. HP is about he same, due I think, to the LS3 manifold. The Shaner ported TB is not a big contribtor ~ $-5 HP? Our race car engine however, spins to red line @ 7900 with a modified GA cam and is still gaining power with same long block and GMPP carb setup. Not a suitable street motor, however.
The point is that a conservative build, using carefully chosen, non exotic parts can make a really fun, long lived, "square" HP=TQ motor. Given the intake manifolds we have to chose from, it is not hard to justify.
This particular car was pulling several car lengths on the "factory" ZR1s a few weeks ago @ Road America.
The dyno is a SuperFlow eddy current which is a dream to VE tune on. I have been able to tune out much of the ~3k torque stall. It does correlate numbers closely with a Dynojet. These numbers are typical of our similar builds which are certainly not dyno queens.
My car is similar except for the stroke and makes a bit more torque commensurate with the extra cubes. HP is about he same, due I think, to the LS3 manifold. The Shaner ported TB is not a big contribtor ~ $-5 HP? Our race car engine however, spins to red line @ 7900 with a modified GA cam and is still gaining power with same long block and GMPP carb setup. Not a suitable street motor, however.
The point is that a conservative build, using carefully chosen, non exotic parts can make a really fun, long lived, "square" HP=TQ motor. Given the intake manifolds we have to chose from, it is not hard to justify.
Last edited by See5; Aug 29, 2008 at 07:41 PM.
I see a lot of tire kickers, but only one graph? This car had a lot more to it than just a heads/cam package. Its the entire combo... Not so much cam, REALLY good heads, good rotating assembly, and every bolt on that could be bolted on...
And no, it isnt easy like everyone says. 530 is very doable around here, 550 is not.
Louis
