The New Shelby GT350
- Thread starter dbk
- Start date
Sinovac
GT Owner
Dave, let me know when they are finished with the Z28. I'm in the market for a lightly used Camaro.
Yeah, Ford was REALLY gentle on it. :lol Camilo's prize Z28 should be here in a few weeks, and it will immediately be for sale. Was ordered pre-rally and was told it would be about 10 weeks until produced.
Sinovac
GT Owner
twobjshelbys
GT Owner
This is classic:
Q: Why black wheels?
A: Actually there’s a reason for that. The brake pads we use, they create so much dust and customers just hate it. You drive the car once with clean wheels and they are dirty after a short drive. So that’s why we got dark wheels.
Q: Why black wheels?
A: Actually there’s a reason for that. The brake pads we use, they create so much dust and customers just hate it. You drive the car once with clean wheels and they are dirty after a short drive. So that’s why we got dark wheels.
Indy GT
Yea, I got one...too
Dave,
Very interesting Q & A session and some interesting information:
Q: Better breathing with flat planes? (Strange question as to influence of the Flat Plane Crank (FPC) on the “intake” side? Should not have any effect. Pistons moving up/down in the bore have no idea if they are controlled by a FPC or a Cross Plane Crank (CPC). But it does have an influence on exhaust scavenging (two 4-cyl engines mated) and rotor dynamics. Just as Ford answered below.)
A: It’s the rotational inertia that it reduces and also from an exhaust standpoint because you’re going side to side, you’re never disturbing the next cylinder’s firing.
Q: This is a pretty big motor for a flat plane crank (big displacement). What have you done in terms of crankshaft damping? (This is a BIG deal and is a very significant accomplishment for Ford engineers. FPC utilization is mostly found on smaller displacement engines where managing the rotor dynamic loads caused by the FPC architecture is a little less challenging. To attempt utilization of a FPC in a large displacement engine without having the engine shake itself apart is a significant engineering achievement.)
A: There’s almost 30 things we did (outside the block) to compensate for it. It’s going to be a whole other story on how we did that.
Q: Challenges with emissions compliance with a flat plane crank?
A: It was harder than usual. (It would be interesting to hear why? Possibly the exhaust pulses of the CPC architecture help backpressure adjacent cylinders and assist in Exhaust Gas Recirculation (EGR) which you do not have in a more free exhaust breathing FPC design.)
Q: Tell us about the variable loading exhaust valve?
A: It’s got an electric valve. So the valve, depending on what driver mode you’re in, the valve will either be open all the time (track mode) or it will open under certain conditions. (Another interesting topic. Implied is removal of parasitic mechanical losses associated with the camshaft and lifters relegating that to electronics. And you can program any valve opening schedule you want with that type of system. But it is unclear why you would want to have the exhaust open “all the time”. Seems to defeat the premise of wanting high Break Mean Effective Pressure (BMEP) throughout the full Otto cycle. And may hurt emissions by allowing unburned air/fuel out the tailpipe.)
Q: How much were you able to share with the 5.0L?
A: There are little common parts (i.e. things in the valve train), but it’s pretty much an all-new engine: new heads, new casting, new intake, new crank, new pistons, new rods, new halfshafts. (So this is interesting- halfshafts. Increased engine weight by their inclusion but necessary for engine balancing because of the FPC. Parasitic losses associated with turning them perhaps offset by removing the losses associated with camshaft/lifer removal.)
Q: Is factory top speed software-limited?
A: No, it is drag-limited. (Good question and interesting response. Vehicle speed is easy to obtain and an often used data variable within the vehicle’s computer systems. Drag on the other hand is not an easy variable to calculate unless in a wind tunnel and varies by a square function of the car through air. Must be some reason to limit vehicle performance by drag over speed. Perhaps there is some aerodynamic instability at certain drag loads with particular atmospheric conditions that should be avoided...? Interesting limitation concept).
Thanks for posting the transcript!
Very interesting Q & A session and some interesting information:
Q: Better breathing with flat planes? (Strange question as to influence of the Flat Plane Crank (FPC) on the “intake” side? Should not have any effect. Pistons moving up/down in the bore have no idea if they are controlled by a FPC or a Cross Plane Crank (CPC). But it does have an influence on exhaust scavenging (two 4-cyl engines mated) and rotor dynamics. Just as Ford answered below.)
A: It’s the rotational inertia that it reduces and also from an exhaust standpoint because you’re going side to side, you’re never disturbing the next cylinder’s firing.
Q: This is a pretty big motor for a flat plane crank (big displacement). What have you done in terms of crankshaft damping? (This is a BIG deal and is a very significant accomplishment for Ford engineers. FPC utilization is mostly found on smaller displacement engines where managing the rotor dynamic loads caused by the FPC architecture is a little less challenging. To attempt utilization of a FPC in a large displacement engine without having the engine shake itself apart is a significant engineering achievement.)
A: There’s almost 30 things we did (outside the block) to compensate for it. It’s going to be a whole other story on how we did that.
Q: Challenges with emissions compliance with a flat plane crank?
A: It was harder than usual. (It would be interesting to hear why? Possibly the exhaust pulses of the CPC architecture help backpressure adjacent cylinders and assist in Exhaust Gas Recirculation (EGR) which you do not have in a more free exhaust breathing FPC design.)
Q: Tell us about the variable loading exhaust valve?
A: It’s got an electric valve. So the valve, depending on what driver mode you’re in, the valve will either be open all the time (track mode) or it will open under certain conditions. (Another interesting topic. Implied is removal of parasitic mechanical losses associated with the camshaft and lifters relegating that to electronics. And you can program any valve opening schedule you want with that type of system. But it is unclear why you would want to have the exhaust open “all the time”. Seems to defeat the premise of wanting high Break Mean Effective Pressure (BMEP) throughout the full Otto cycle. And may hurt emissions by allowing unburned air/fuel out the tailpipe.)
Q: How much were you able to share with the 5.0L?
A: There are little common parts (i.e. things in the valve train), but it’s pretty much an all-new engine: new heads, new casting, new intake, new crank, new pistons, new rods, new halfshafts. (So this is interesting- halfshafts. Increased engine weight by their inclusion but necessary for engine balancing because of the FPC. Parasitic losses associated with turning them perhaps offset by removing the losses associated with camshaft/lifer removal.)
Q: Is factory top speed software-limited?
A: No, it is drag-limited. (Good question and interesting response. Vehicle speed is easy to obtain and an often used data variable within the vehicle’s computer systems. Drag on the other hand is not an easy variable to calculate unless in a wind tunnel and varies by a square function of the car through air. Must be some reason to limit vehicle performance by drag over speed. Perhaps there is some aerodynamic instability at certain drag loads with particular atmospheric conditions that should be avoided...? Interesting limitation concept).
Thanks for posting the transcript!
Xcentric
GT Owner
Bill I read this as a butterfly valve in the exhaust pipe, not an electrically actuated exhaust valve in the cylinder head.
Right?
Q: Tell us about the variable loading exhaust valve?
A: It’s got an electric valve. So the valve, depending on what driver mode you’re in, the valve will either be open all the time (track mode) or it will open under certain conditions. (Another interesting topic. Implied is removal of parasitic mechanical losses associated with the camshaft and lifters relegating that to electronics. And you can program any valve opening schedule you want with that type of system. But it is unclear why you would want to have the exhaust open “all the time”. Seems to defeat the premise of wanting high Break Mean Effective Pressure (BMEP) throughout the full Otto cycle. And may hurt emissions by allowing unburned air/fuel out the tailpipe.)
Right?
Q: Tell us about the variable loading exhaust valve?
A: It’s got an electric valve. So the valve, depending on what driver mode you’re in, the valve will either be open all the time (track mode) or it will open under certain conditions. (Another interesting topic. Implied is removal of parasitic mechanical losses associated with the camshaft and lifters relegating that to electronics. And you can program any valve opening schedule you want with that type of system. But it is unclear why you would want to have the exhaust open “all the time”. Seems to defeat the premise of wanting high Break Mean Effective Pressure (BMEP) throughout the full Otto cycle. And may hurt emissions by allowing unburned air/fuel out the tailpipe.)
Sinovac
GT Owner
Yes-it's in the exhaust.
I agree with Bill that a 5.2 FPC is a big achievement for Ford. I'm interested to see what the lower rotating assembly looks like and how it was balanced.
I agree with Bill that a 5.2 FPC is a big achievement for Ford. I'm interested to see what the lower rotating assembly looks like and how it was balanced.
Indy GT
Yea, I got one...too
Gary, you may be correct. Drag certainly does limit speed and this just might be a way of saying there is no electronic "speed" governor because the terminal speed of the vehicle is below that which the design team does not want to exceed. Good interpretation!
Andy, I am not sure of what the exhaust valving entails. I was thinking conventionally with intake valve(s) and exhaust valve(s) actually in the cylinder head exposed to the combustion high pressure gas. Perhaps there is some more advance butterfly arrangement which you speculate. It will be very interesting to learn the more technical aspects of this power plant.
Sinovac
GT Owner
You're over thinking it Bill. It's just a dual mode exhaust.
On another note, the choice of 19" wheels permits many options for tires. The Pirelli Trofeo R, my current favorite DOT tire, has many tires in this size.
On another note, the choice of 19" wheels permits many options for tires. The Pirelli Trofeo R, my current favorite DOT tire, has many tires in this size.
twobjshelbys
GT Owner
There are a lot of questions about this engine. I expect we will see some technical papers and presentations at things like SAE conventions in the future.
In fact, SAE already has some info:
http://articles.sae.org/13712/
http://articles.sae.org/13709/
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The butterfly in the exhaust is pretty common these days, can be vacuum actuated, and defeated with the "golf tee" method (I had an Audi S4, I did this to), and just got an M3 that has electronic butterflies, and you can set it to a mode where they are open, and unplug the connector to lock them open.
If you have Bloomberg TV, Jamal is doing an interview sometime around 11:15-11:30 PST this morning. Not sure if they will air it live.
Indy GT
Yea, I got one...too
Was not live. Bloomberg just had a segment with Infinity CEO from LA auto show.
Perhaps Jamal will be on later....
Perhaps Jamal will be on later....