[Z06] why does 5.0 have better hp/ci than 7.0?
#1
Drifting
Thread Starter
why does 5.0 have better hp/ci than 7.0?
This bothers me. My Ford friend pointed this out to Me. The 5.0 boss and base gt both are better and are 11:1cr. The ls6 is 11:1 too. The heads are no slouch. Cam isn't tiny. Any input?
#2
Former Vendor
you mean an ls7? its may have something to do with 4 valves per cylinder, 4 independently variable camshafts..
#3
Le Mans Master
The LS7 is a basic pushrod motor while the new 5.0 and Boss 302R use the latest technological advances to maximize power output. Corvettes are faster than mustangs because of the platform not because of powerplant superiority.
Last edited by Wulverine; 04-29-2012 at 01:19 PM.
#4
Le Mans Master
why does todays 5.0 put out 412 hp while the 1987 LX 5.0 L put out 225 hp ??? Same answer, technology and engineering.
#6
Le Mans Master
While Fords new 5.0 is a stellar engine design for sure, the whole thing on why such large displacement LS engines, has been a long time topic. Best thinking of an engine as a power package, not really knowing what's inside. LS engines are physically compact, lightweight, getting better fuel milage than many smaller displacement engines. And certainly no argument on what displacement does for low end torque. The 440 lb LS7 makes torque everywhere, and still 25 highway mpg. What else do you need to know.
#7
Team Owner
The 5.0 coyote motor is amazing. My wife has a 2012 GT and it runs hard, really hard. At the drag strip this weekend it destroyed every single camaro and vette there expect for 2 camaros with blowers/cams/etc making >600rwhp. The fastest n/a 5th gen camaro was running 13.3s vs her basically stock 2012 GT running 13.0s. Ford finally did something right for once.
#9
GM missed the boat when they dropped the LT5, IMHO. True variable valve timing with independent camshafts will always trump a single cam design. Or what would be even better yet would be a solenoid operated valve train.
#10
Safety Car
If I did the math right that'd be about 580HP N/A (if it was equal to the 5.0 ratio) pretty hard to do that and still pass emissions I would think, let alone reliable for a 5yr/100, for the price of a Z06, etc
#11
Team Owner
616hp if you use the 440hp Boss motor.
440HP/5L=88 HP/L
7L*88HP=616HP.
440HP/5L=88 HP/L
7L*88HP=616HP.
#12
Drifting
My stock LS7 put out 470 lb ft of torque. How much torque does the 5.0 put out? Or better yet, how much torque does it put out at 2000 rpm where EVERYONE drives on the street? Mine put out just over 400. Also, the design parameters GM selected to adhere to for the Z06 engine were rooted in the requirement for a physically small package and a very low weight. The 5.0 is neither and that's why GM stuck with the basic package that they did. If you want to road race, torque and weight are your biggest friends. People tend to forget that the Z06 was never designed to be a drag car. Finally, are you REALLY sure the 5.0 puts out 440 hp. I know that the old 5.0 fuel injected, pushrod motor didn't put out any where near the claimed 225 hp.
Gary
Gary
#13
Le Mans Master
#14
Racer
14.5@96mph stock at 2500ft... cant believe i actually thought it was fast. Real fast.
#15
Le Mans Master
The Coyote motor is the first FORD (and probably American) V8 that has intake ports as straight as the ports on finds on Ferraris. That is the port is stratight vertical (down) in the head and then the intake manifolds (Boss 302 version) are straight down from the intake helmholtz resonator.
Ford has finally caught up to where Ferrari was in 1989 when the 348 motor was introduced.
Heads that breath better do not need as big a cam to rev just as high or higher, and work just fin down low.
However displacement is still the major determinant to TQ, especially the shape fo the curve below peak. Not needing as big a cam helps the TQ curve below peak, so better breathing delivers twice--up top and down low.
#16
Team Owner
My stock LS7 put out 470 lb ft of torque. How much torque does the 5.0 put out? Or better yet, how much torque does it put out at 2000 rpm where EVERYONE drives on the street? Mine put out just over 400. Also, the design parameters GM selected to adhere to for the Z06 engine were rooted in the requirement for a physically small package and a very low weight. The 5.0 is neither and that's why GM stuck with the basic package that they did. If you want to road race, torque and weight are your biggest friends. People tend to forget that the Z06 was never designed to be a drag car. Finally, are you REALLY sure the 5.0 puts out 440 hp. I know that the old 5.0 fuel injected, pushrod motor didn't put out any where near the claimed 225 hp.
Gary
Gary
Here is a chart I pulled up from a quick search showing a base 5.0 motor and a boss 5.0 motor. Both have nice torque, but like I said, nothing compared to an LS7.
#17
Tech Contributor
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GM missed the boat when they dropped the LT5, IMHO. An LT5 isn't a light engine, and it doesn't package well. True variable valve timing with independent camshafts will always trump a single cam design. Or what would be even better yet would be a solenoid operated valve train.
#18
Burning Brakes
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Then why is it that both the 385hp and the 405hp hp pushrod LS6 Z06 walks the 400hp LT5 ZR1 in every performance/acceleration category except top speed, and even that is more of a gearing issue.
#19
Burning Brakes
Smaller displacements are a little bit more efficient as well in producing power, keep that in mind. The Toyota Celica produced over 100 bhp/liter way back in 1999 in their 1.8L engine (189 hp initially). Granted that was much much smaller and an I4 of course, but if you simply added another bank of cylinders and doubled the displacement, Toyota wouldn't have been able to pull nearly 400 hp from a 3.6L engine
Also think about the time gap in when these engines were developed. IIRC the LS7 began development as far back as 2002. I think Katech has mentioned this before here on the forum. The Coyote 5.0L was first conceived in 2007:
http://www.mustang50magazine.com/tec...ine/index.html
When the LS7 came out in 2005 it was the most powerful production naturally aspirated V8 on the market until Mercedes AMG came out with their 6.3L S63 engine (also DOHC 4V) in 2006, and Ferrari bumped up the F430 Scuderia output to 508 hp in 2007. The fact that GM managed that with push rods and 2 valves per cylinder is pretty awesome if you ask me. I'm sure GM had plenty of good reasons to maintain the pushrod design for the LS7, namely keeping the engine and car affordable enough for guys like me ha ha.
The only thing "wrong" with the LS7 is that time marches on and technology and development advances.
As others have rightly pointed out the old 5.0L Ford motor doesn't hold a candle to the 5.0L Coyote for similar reasons. Even guys who take the fox body old motor, and work it over with an aggressive H/C/I typically have to also stroke the motor for more displacement to get past the power levels of the new factory stock, emissions compliant, warranty backed 5.0L Coyote.
Also think about the time gap in when these engines were developed. IIRC the LS7 began development as far back as 2002. I think Katech has mentioned this before here on the forum. The Coyote 5.0L was first conceived in 2007:
http://www.mustang50magazine.com/tec...ine/index.html
When the LS7 came out in 2005 it was the most powerful production naturally aspirated V8 on the market until Mercedes AMG came out with their 6.3L S63 engine (also DOHC 4V) in 2006, and Ferrari bumped up the F430 Scuderia output to 508 hp in 2007. The fact that GM managed that with push rods and 2 valves per cylinder is pretty awesome if you ask me. I'm sure GM had plenty of good reasons to maintain the pushrod design for the LS7, namely keeping the engine and car affordable enough for guys like me ha ha.
The only thing "wrong" with the LS7 is that time marches on and technology and development advances.
As others have rightly pointed out the old 5.0L Ford motor doesn't hold a candle to the 5.0L Coyote for similar reasons. Even guys who take the fox body old motor, and work it over with an aggressive H/C/I typically have to also stroke the motor for more displacement to get past the power levels of the new factory stock, emissions compliant, warranty backed 5.0L Coyote.
#20
Burning Brakes
My stock LS7 put out 470 lb ft of torque. How much torque does the 5.0 put out? Or better yet, how much torque does it put out at 2000 rpm where EVERYONE drives on the street? Mine put out just over 400. Also, the design parameters GM selected to adhere to for the Z06 engine were rooted in the requirement for a physically small package and a very low weight. The 5.0 is neither and that's why GM stuck with the basic package that they did. If you want to road race, torque and weight are your biggest friends. People tend to forget that the Z06 was never designed to be a drag car. Finally, are you REALLY sure the 5.0 puts out 440 hp. I know that the old 5.0 fuel injected, pushrod motor didn't put out any where near the claimed 225 hp.
Gary
Gary
1993-1993 5.0 205hp