Le nouveau LS7 en details
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SE_Sun1997
New member
....
malade!!
90mm de throttle body, yen rentre de lair dans cte bete la :bigup:
ca vire plus que mon 4 cylindre.....
*tu*
malade!!
90mm de throttle body, yen rentre de lair dans cte bete la :bigup:
ca vire plus que mon 4 cylindre.....
*tu*
Liquid Snake
Well-known member
*jawdrop* *jawdrop* Tellement hate de la voir pr vrai cette C6 Z06 là!!!
tuperwareman
Legacy Member
and to think they call pushrod motors obsolete.
I want one!!!
I want one!!!
Street Machine
Legacy Member
Here's one of my own pics
jonnycowboy
Legacy Member
whats the diff between a small block and a big block if the displacement is the same? the old 427 was a big block and this one's a small one.. just a difference in casting styles?
and why don't they use their ecotec 4-cyl expertise and make this baby a DOHC 32V?
bmw in the new M5 (5L, 2L less than this corvette) can get 507hp and a redline of 8250rpm (~1000 more than the corvette). Since we know the engineers at chevy can do it, is there any reason to stick with this archaic pushrod technology?
and why don't they use their ecotec 4-cyl expertise and make this baby a DOHC 32V?
bmw in the new M5 (5L, 2L less than this corvette) can get 507hp and a redline of 8250rpm (~1000 more than the corvette). Since we know the engineers at chevy can do it, is there any reason to stick with this archaic pushrod technology?
jonnycowboy said:
Yep, the difference is the casting.
As for the HP/L stuff- one thing FSAE teaches us is that it's all about a=F/m..and the LS7 weighs nearly 80 pounds less than the BMW V10 (in fact, it's also lighter than their I6 engines). I don't see why it's an archaic valvetrain if it allows the engine to rev higher than most DOHC V8s while lowering its CG and reducing overall dimensions, plus the weight benefit.
jonnycowboy
Legacy Member
wow i didnt know the chevy was 80 pounds less!
though i mean 2-valve technology isn't exactly the pinnacle, there is a reason why all newly developped racecar engines (f1, etc) have more than 2 valves! - i think to distribute the torque band and to have a nicer power curve (more effective power, area under the curve)
though i mean 2-valve technology isn't exactly the pinnacle, there is a reason why all newly developped racecar engines (f1, etc) have more than 2 valves! - i think to distribute the torque band and to have a nicer power curve (more effective power, area under the curve)
Well, to take F1 as an example (even though the actual valvetrains don't have anything in common), since engine regulations are so tight, the only way to make more power is to rev higher. OHC layouts have an advantage for high-RPM operation for a couple of reasons: the valvetrain is stiffer, so the valves can be controlled more precisely (a nice thing to have when you're dealing with bits of very expensive metal that are repeatedly trying to bash into each other a couple of hundred times a second); and increasing the number of valves also tends to increase the ratio between valve area and piston area, which in turn will reduce port airflow speeds at a given RPM (as per Bernoulli).
The latter has two effects: the airflow reaches its optimum speed later in the rev range, increasing HP at high speeds, but doesn't have enough low-RPM velocity to provide good combustion. Which is why a VTEC engine has no low-end torque, while, say, a 2.3L Quad 4 - God bless its crappy little mechanical soul - has decent torque but sputters out when you pile on the revs, because the airflow gets too quick and starts choking the ports.
There's a lot more to it (for instance the LS7 has really aggressive cam profiles and port geometry, which help it breathe up to 7K while still keeping decent low-RPM grunt), but for a street application, I don't think a DOHC layout necessarily has an inherent advantage.
FWIW, the C5-R kicked butt in GT racing with the LS7's predecessor and I'm sure the C6-R will keep it up.
The latter has two effects: the airflow reaches its optimum speed later in the rev range, increasing HP at high speeds, but doesn't have enough low-RPM velocity to provide good combustion. Which is why a VTEC engine has no low-end torque, while, say, a 2.3L Quad 4 - God bless its crappy little mechanical soul - has decent torque but sputters out when you pile on the revs, because the airflow gets too quick and starts choking the ports.
There's a lot more to it (for instance the LS7 has really aggressive cam profiles and port geometry, which help it breathe up to 7K while still keeping decent low-RPM grunt), but for a street application, I don't think a DOHC layout necessarily has an inherent advantage.
FWIW, the C5-R kicked butt in GT racing with the LS7's predecessor and I'm sure the C6-R will keep it up.
FranksGTP
Legacy Member
tuperwareman said:
It seems as though some don't know the difference between Obsolete and Refined. Taken into account that this is still a budget engine. Made for a sports car that the above average income middle aged crisis male can afford.
Now, Alls I gotta do is get a good 57 belair chassis, one of these motors in a crate, 1million dollar lottery ticket so I can quit my job and figure out how to mate them both together
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