Unlikely base MEC using “upgraded LT1”
01-19-2019, 11:00 PM
#221
Race Director
Listen to every upshift, there is an audible noise (clunk/pop/click/whatever you want to call it).
The noise is very obvious in the beginning of the video when the car turns on to the highway and the driver is short shifting it.
The noise is very obvious in the beginning of the video when the car turns on to the highway and the driver is short shifting it.
Last edited by jimmyb; 01-20-2019 at 04:55 PM.
01-19-2019, 11:53 PM
#222
01-20-2019, 05:58 PM
#223
Yeah you can have the "modern" engine that is bigger, heavier, makes lower power and torque, and gets worse gas mileage
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01-20-2019, 07:55 PM
#224
Le Mans Master
Many people associate these engines as being better and do not understand why they are used by the europeans and not the Americans.
01-20-2019, 08:22 PM
#225
Race Director
I read an article on the Cadillac Blackwing engine and it stated that there were two main reasons for them going with the DOHC engine. One was that it was perceived to be smoother running and the other was that it was perceived to be higher quality. All based on perception.
01-20-2019, 08:25 PM
#226
Le Mans Master
I read an article on the Cadillac Blackwing engine and it stated that there were two main reasons for them going with the DOHC engine. One was that it was perceived to be smoother running and the other was that it was perceived to be higher quality. All based on perception.
01-20-2019, 08:57 PM
#227
Le Mans Master
Funny reading things like this considering a sports car is supposed to be a lightweight car built with handling in mind, and a pushrod V8 fits that bill perfectly considering its physically smaller and lighter than a DOHC counterpart, and because of that smaller size it can be mounted closer to the ground and closer to the center of the chassis for better weight distribution and better center of gravity.
Yeah you can have the "modern" engine that is bigger, heavier, makes lower power and torque, and gets worse gas mileage
Yeah you can have the "modern" engine that is bigger, heavier, makes lower power and torque, and gets worse gas mileage
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01-20-2019, 09:04 PM
#228
01-20-2019, 09:44 PM
#229
01-20-2019, 11:18 PM
#231
Le Mans Master
because you could make a cheaper and lighter 7.2 that would easily outperform the heavier, more expensive, more complex dohc with higher center of gravity engine. It would also be far more fun to drive.
this is the reason your lt5 died with the c4
that is until you factor in tomorrow’s gov regulations.
Last edited by NY09C6; 01-20-2019 at 11:20 PM.
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01-20-2019, 11:26 PM
#232
Can you get the coyote block to 6.2L? Would you need a different (bigger) block? Image the size and weight if you would need a bigger block...
You're also assuming every manufacturer is trying to max their engine out, when basically none of them are. Power goal comes first, then the engine, not the other way around. So in the case of the C7 for example, with its current ~460hp power goal, why would GM want to use a bigger, heavier DOHC V8 to meet that goal when the lighter, smaller pushrod engine does it?
Never implied "right" and "wrong", but rather who is doing it better. Up until recently many european and asian countries had displacement taxes, forcing manufacturers to build smaller displacement engines and rely on higher revs (or forced induction) to make power, that is much easier with OHC, especially considering vast majority of their engines are I3, I4s and I6s, all of which don't benefit from the OHV layout. So naturally when making a V8, 10, 12 etc. they go with what they already know as well and do a OHC layout. In the US we don't have such moronic taxes so there is no reason to build smaller displacement engines for performance cars, plus Americans prefer larger displacement engines anyway.
With that being said look at the cars that do use the OHV V8 layout who are not doing so because of budget, so I guess cars like the Ultima GTR is wrong for using an old tech pushrod engine then? What about the Saleen S7? Mosler MT900? Zenvo ST1? SSC aero?
If the DOHC layout is so much superior for V8s why is the LSx the most commonly swapped engine on the market, replacing numerous different DOHC engines and having owners ignore numerous different DOHC engines they could have swapped into their cars - but chose not to? And it seems like majority of these swaps are imports, so its not like there is a heavy bias for Chevy with them, if anything there is the typical blind bias against them because its an American brand. So why, with all odds against the LSx, is it so commonly swapped, wanted and praised engine? You can easily pick up a "high tech" modular V8, Northstar V8, 1UZ, or VK56 from a junk yard for cheap, so why are there so few of those swap but so many of the LSx swaps? Oh wait, is it that the LSx is significantly smaller, and lighter while making significantly more power, torque and being significantly easier to work on/get more power out of?
We've had this conversion before and you were shut down quickly with no response so I don't know why you are bothering again.
You're also assuming every manufacturer is trying to max their engine out, when basically none of them are. Power goal comes first, then the engine, not the other way around. So in the case of the C7 for example, with its current ~460hp power goal, why would GM want to use a bigger, heavier DOHC V8 to meet that goal when the lighter, smaller pushrod engine does it?
How could u possibly think that every other manufacturer of mid-engine automobiles could have it sooo wrong while GM has sooo right?
With that being said look at the cars that do use the OHV V8 layout who are not doing so because of budget, so I guess cars like the Ultima GTR is wrong for using an old tech pushrod engine then? What about the Saleen S7? Mosler MT900? Zenvo ST1? SSC aero?
If the DOHC layout is so much superior for V8s why is the LSx the most commonly swapped engine on the market, replacing numerous different DOHC engines and having owners ignore numerous different DOHC engines they could have swapped into their cars - but chose not to? And it seems like majority of these swaps are imports, so its not like there is a heavy bias for Chevy with them, if anything there is the typical blind bias against them because its an American brand. So why, with all odds against the LSx, is it so commonly swapped, wanted and praised engine? You can easily pick up a "high tech" modular V8, Northstar V8, 1UZ, or VK56 from a junk yard for cheap, so why are there so few of those swap but so many of the LSx swaps? Oh wait, is it that the LSx is significantly smaller, and lighter while making significantly more power, torque and being significantly easier to work on/get more power out of?
We've had this conversion before and you were shut down quickly with no response so I don't know why you are bothering again.
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01-21-2019, 12:02 AM
#233
Le Mans Master
Can you get the coyote block to 6.2L? Would you need a different (bigger) block? Image the size and weight if you would need a bigger block...
You're also assuming every manufacturer is trying to max their engine out, when basically none of them are. Power goal comes first, then the engine, not the other way around. So in the case of the C7 for example, with its current ~460hp power goal, why would GM want to use a bigger, heavier DOHC V8 to meet that goal when the lighter, smaller pushrod engine does it?
Never implied "right" and "wrong", but rather who is doing it better. Up until recently many european and asian countries had displacement taxes, forcing manufacturers to build smaller displacement engines and rely on higher revs (or forced induction) to make power, that is much easier with OHC, especially considering vast majority of their engines are I3, I4s and I6s, all of which don't benefit from the OHV layout. So naturally when making a V8, 10, 12 etc. they go with what they already know as well and do a OHC layout. In the US we don't have such moronic taxes so there is no reason to build smaller displacement engines for performance cars, plus Americans prefer larger displacement engines anyway.
With that being said look at the cars that do use the OHV V8 layout who are not doing so because of budget, so I guess cars like the Ultima GTR is wrong for using an old tech pushrod engine then? What about the Saleen S7? Mosler MT900? Zenvo ST1? SSC aero?
If the DOHC layout is so much superior for V8s why is the LSx the most commonly swapped engine on the market, replacing numerous different DOHC engines and having owners ignore numerous different DOHC engines they could have swapped into their cars - but chose not to? And it seems like majority of these swaps are imports, so its not like there is a heavy bias for Chevy with them, if anything there is the typical blind bias against them because its an American brand. So why, with all odds against the LSx, is it so commonly swapped, wanted and praised engine? You can easily pick up a "high tech" modular V8, Northstar V8, 1UZ, or VK56 from a junk yard for cheap, so why are there so few of those swap but so many of the LSx swaps? Oh wait, is it that the LSx is significantly smaller, and lighter while making significantly more power, torque and being significantly easier to work on/get more power out of?
We've had this conversion before and you were shut down quickly with no response so I don't know why you are bothering again.
You're also assuming every manufacturer is trying to max their engine out, when basically none of them are. Power goal comes first, then the engine, not the other way around. So in the case of the C7 for example, with its current ~460hp power goal, why would GM want to use a bigger, heavier DOHC V8 to meet that goal when the lighter, smaller pushrod engine does it?
Never implied "right" and "wrong", but rather who is doing it better. Up until recently many european and asian countries had displacement taxes, forcing manufacturers to build smaller displacement engines and rely on higher revs (or forced induction) to make power, that is much easier with OHC, especially considering vast majority of their engines are I3, I4s and I6s, all of which don't benefit from the OHV layout. So naturally when making a V8, 10, 12 etc. they go with what they already know as well and do a OHC layout. In the US we don't have such moronic taxes so there is no reason to build smaller displacement engines for performance cars, plus Americans prefer larger displacement engines anyway.
With that being said look at the cars that do use the OHV V8 layout who are not doing so because of budget, so I guess cars like the Ultima GTR is wrong for using an old tech pushrod engine then? What about the Saleen S7? Mosler MT900? Zenvo ST1? SSC aero?
If the DOHC layout is so much superior for V8s why is the LSx the most commonly swapped engine on the market, replacing numerous different DOHC engines and having owners ignore numerous different DOHC engines they could have swapped into their cars - but chose not to? And it seems like majority of these swaps are imports, so its not like there is a heavy bias for Chevy with them, if anything there is the typical blind bias against them because its an American brand. So why, with all odds against the LSx, is it so commonly swapped, wanted and praised engine? You can easily pick up a "high tech" modular V8, Northstar V8, 1UZ, or VK56 from a junk yard for cheap, so why are there so few of those swap but so many of the LSx swaps? Oh wait, is it that the LSx is significantly smaller, and lighter while making significantly more power, torque and being significantly easier to work on/get more power out of?
We've had this conversion before and you were shut down quickly with no response so I don't know why you are bothering again.
Again, go ask every other manufacturer why. Its incumbent on you to justify why other manufacturers who choose not to follow GMs path could possibly be so wrong. Maybe they haven’t had the epiphany you have had.
As for high center of gravity, u can increase the V angle and negate that. Lotus originally wanted to do a V angle > 90 on the LT-5. The only reason the motor was as “tall” was to allow it to fit between the frame rails of the C4 when installing it from beneath. BTW, The LT-5 still fit comfortably under the STOCK hood of a C4.
01-21-2019, 06:55 AM
#234
And just like before, totally dodging all the questions. Is it because you cannot answer, or because you just don't want to admit the truth?
As for high center of gravity, u can increase the V angle and negate that. Lotus originally wanted to do a V angle > 90 on the LT-5.
The only reason the motor was as “tall” was to allow it to fit between the frame rails of the C4 when installing it from beneath.
BTW, The LT-5 still fit comfortably under the STOCK hood of a C4.
01-21-2019, 07:47 AM
#235
Le Mans Master
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JD AMG already did. To add to what he said, GM has a lot more experience developing pushrod engines to high power levels than most of the foreign manufacturers. For a foreign manufacturer without that recent experience, an overhead cam is the obvious choice. They may not even have engineers there any more who have even ever designed a high-power modern pushrod engine.
Another factor is that overhead cams don't offer much of an advantage on larger displacement engines. Overhead cams can be great on engines which rev super-high, but the larger displacement engines are limited by piston speed (how far the piston travels in feet-per-second), if they are intended to have good longevity, so they can't take advantage of the higher-revving capability anyway. I'd be fine if they just dropped the LT4 or 5 engine into the C8.
However, because of the many less-educated who think an OHC is inherently superior, at least one of the engines available in the M8 will be a version of the Cadillac "Hot V" turbo DOHC engine. Largely marketing, but also a possibility for better fuel economy, if they don't try to wring too much power out of that engine.
Last edited by Warp Factor; 01-21-2019 at 10:50 AM.
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01-21-2019, 08:10 AM
#236
Race Director
Don't get hung up on internal size (6.2L verses 5L or whatever). The SBC is a great powerplant for packaging because of it's very compact EXTERNAL size. Obviously, a DOHC 4 valve head V8 flows a LOT more than the SBC. It's also more complex, heavier, taller, wider, etc.
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01-21-2019, 10:32 AM
#237
Safety Car
Funny reading things like this considering a sports car is supposed to be a lightweight car built with handling in mind, and a pushrod V8 fits that bill perfectly considering its physically smaller and lighter than a DOHC counterpart, and because of that smaller size it can be mounted closer to the ground and closer to the center of the chassis for better weight distribution and better center of gravity.
Yeah you can have the "modern" engine that is bigger, heavier, makes lower power and torque, and gets worse gas mileage
Yeah you can have the "modern" engine that is bigger, heavier, makes lower power and torque, and gets worse gas mileage
01-21-2019, 11:01 AM
#238
Le Mans Master
....
Another factor is that overhead cams don't offer much of an advantage on larger displacement engines. Overhead cams can be great on engines which rev super-high, but the larger displacement engines are limited by piston speed (how far the piston travels in feet-per-second), if they are intended to have good longevity, so they can't take advantage of the higher-revving capability anyway. I'd be fine if they just dropped the LT4 or 5 engine into the C8.
However, because of the many less-educated who think an OHC is inherently superior, at least one of the engines available in the M8 will be a version of the Cadillac "Hot V" turbo DOHC engine. Largely marketing, but also a possibility for better fuel economy, if they don't try to wring too much power out of that engine.
Another factor is that overhead cams don't offer much of an advantage on larger displacement engines. Overhead cams can be great on engines which rev super-high, but the larger displacement engines are limited by piston speed (how far the piston travels in feet-per-second), if they are intended to have good longevity, so they can't take advantage of the higher-revving capability anyway. I'd be fine if they just dropped the LT4 or 5 engine into the C8.
However, because of the many less-educated who think an OHC is inherently superior, at least one of the engines available in the M8 will be a version of the Cadillac "Hot V" turbo DOHC engine. Largely marketing, but also a possibility for better fuel economy, if they don't try to wring too much power out of that engine.
You should all get together and develop a Powerpoint to take on ur manufacturer “OHV EPIPHANY TOUR” so u can show the rest of the world what they don’t know about engine design. Looks like u will need to include GM Powertain on that soon too.
01-21-2019, 12:01 PM
#239
Burning Brakes
Engines are simply big air pumps, with a little bang between induction and exhaust... more air and/or more bang with out destroying the pump, means bigger power...
For me, technology is sometimes cool and other times, packaging matters (whether it be for width, hight, length, weight, etc).
Why do all debates on this forum devolve into a "versus" match... both technologies (ohc/pushrod) have their place for various reasons.
For me, technology is sometimes cool and other times, packaging matters (whether it be for width, hight, length, weight, etc).
Why do all debates on this forum devolve into a "versus" match... both technologies (ohc/pushrod) have their place for various reasons.
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01-21-2019, 01:00 PM
#240
Le Mans Master
because you could make a cheaper and lighter 7.2 that would easily outperform the heavier, more expensive, more complex dohc with higher center of gravity engine. It would also be far more fun to drive.
this is the reason your lt5 died with the c4
that is until you factor in tomorrow’s gov regulations.
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