Toyota GR Supra Races Into 2021 with More Power and First-Ever Four-Cylinder Turbo Model

[Reppunkamui]

Aluminium is lighter than steel. Internal manifold is aluminium alloy of the engine block, vs the steel of the exhaust manifold.

As mentioned, I can't be sure about the flow, since to me it purely depends on the piping design of the internal manifold vs the steel manifold. Same size connections from cylinder to manifold and from manifold to turbo. B58M1 is an improvement over the B58M0 with more power, adding an exhaust flow restriction seems like an odd decision.

Sponsored

 

[harddrivin1le]

Aluminium is lighter than steel. Internal manifold is aluminium alloy of the engine block, vs the steel of the exhaust manifold.

As mentioned, I can't be sure about the flow, since to me it purely depends on the piping design of the internal manifold vs the steel manifold. Same size connections from cylinder to manifold and from manifold to turbo. B58M1 is an improvement over the B58M0 with more power, adding an exhaust flow restriction seems like an odd decision.

Ae you kidding me?

The "aluminum manifold" is simply part of the Supra's head casting! Any difference in the weight of those two head casting is minuscule!

Get a mechanical engineering degree like the one I've held since 1986 and you'll be certain that the 6 port head/manifold flow far more efficiently than the 2 port arrangement. And why would BMW bother specifying the 6 port arrangement for it's more powerful variants if it didn't? Would they intentionally spend more money for less performance?

 

[Supra Guy]

The 2021 car's trap speed will be some 5-6 MPH faster.

All races don't end at 60 MPH.

At speed (especially from 80 MPH and up), the 2021 car will decisively pull on the 2020, realizing that the 2021 car is some 50 - 60 HP stronger (at the crank).

The differences in those two engines are extensive.

True the guys who track corrected me on that. I was more less talking about the regular people who daily drive the car wouldn’t notice as much as track people. They are both awesome cars.

I think it’s the retail value in the second hand market that will effect the 2020 sellers. The Corvette had the same problem with 01 ZO6 385hp vs the 405 for 02 and up at the time. It was only 20hp difference but 405 sounds better that 385 does.

 

[harddrivin1le]

Aluminium is lighter than steel. Internal manifold is aluminium alloy of the engine block, vs the steel of the exhaust manifold.

As mentioned, I can't be sure about the flow, since to me it purely depends on the piping design of the internal manifold vs the steel manifold. Same size connections from cylinder to manifold and from manifold to turbo. B58M1 is an improvement over the B58M0 with more power, adding an exhaust flow restriction seems like an odd decision.

2020 BMW M340i (455 pounds heavier than the Supra in the link below):

https://www.caranddriver.com/reviews/a30143002/2020-bmw-m340i-reliability-maintenance/

2020 Supra:
https://www.caranddriver.com/reviews/a27440454/2020-toyota-supra-by-the-numbers/

Both cars were tested by the same magazine (consistency in testing methodology).

Despite being 455 pounds heavier, the BMW M340i (exactly the same engine used in the 2021 Supra) posted the same 12.3 second ET as the 2020 Supra, but was actually 2 MPH faster (trap speed)!

Hale's formula tells us that the 2021 Supra should therefore trap in the 118 MPH region, which is some 5 - 6 MPH faster than the 2020 model.

 

[harddrivin1le]

True the guys who track corrected me on that. I was more less talking about the regular people who daily drive the car wouldn’t notice as much as track people. They are both awesome cars.

I think it’s the retail value in the second hand market that will effect the 2020 sellers. The Corvette had the same problem with 01 ZO6 385hp vs the 405 for 02 and up at the time. It was only 20hp difference but 405 sounds better that 385 does.

To your point, the 2020 Supras are going to take a hit in resale value. Also, Toyota's stated that the 2021 Supra will be less expensive (feature for feature), though hasn't yet elaborated on the details.

 

[Reppunkamui]

Ae you kidding me?

The "aluminum manifold" is simply part of the Supra's head casting! And difference in the weight of those two head casting is minuscule!

Get a mechanical engineering degree like the one I've held since 1986 and you'll be certain that the 6 port head/manifold flow far more efficiently than the 2 port arrangement. And why would BMW bother specifying the 6 port arrangement for it's more powerful variants if it didn't? Would they intentionally spend more money for less performance?

No offense. But this is the internet and by saying you are a retired mechanical engineer bears no weight without any proof. Personally by having to resort to this to back your statements of opinion, I question the credentials further as you are not able to support your statement with clear logic.

As I mentioned before. I believe the 6 port configuration for more powerful applications is for the stronger steel exhaust manifold to handle higher pressure and thermal load. I.e. can be tuned harder.

The 2 port does not replace the 6 port... obviously it is still a 6 port with one for each cylinder. It just has the manifold integrated in the engine block. The flow is purely a comparison of the design of this internal manifold vs the external one. I don't profess to know which flow is better, but I am certainly not going to be convinced by "it just is" from random dude on the internet. Especially since there are other B58 models with the 6 port that generates lower performance.

Lets just leave it as we agree to disagree...

 

[Reppunkamui]

2020 BMW M340i (455 pounds heavier than the Supra in the link below):

https://www.caranddriver.com/reviews/a30143002/2020-bmw-m340i-reliability-maintenance/

2020 Supra:
https://www.caranddriver.com/reviews/a27440454/2020-toyota-supra-by-the-numbers/

Both cars were tested by the same magazine (consistency in testing methodology).

Despite being 455 pounds heavier, the BMW M340i (exactly the same engine used in the 2021 Supra) posted the same 12.3 second ET as the 2020 Supra, but was actually 2 MPH faster (trap speed)!

Hale's formula tells us that the 2021 Supra should therefore trap in the 118 MPH region, which is some 5 - 6 MPH faster than the 2020 model.

Genuinely interesting, but not sure how it relates to the quote.

That said, wasn't it part of the announcement that the 2021 Supra is more powerful and accelerates faster?

 

[harddrivin1le]

No offense. But this is the internet and by saying you are a retired mechanical engineer bears no weight without any proof. Personally by having to resort to this to back your statements of opinion, I question the credentials further as you are not able to support your statement with clear logic.

As I mentioned before. I believe the 6 port configuration for more powerful applications is for the stronger steel exhaust manifold to handle higher pressure and thermal load. I.e. can be tuned harder.

The 2 port does not replace the 6 port... obviously it is still a 6 port with one for each cylinder. It just has the manifold integrated in the engine block. The flow is purely a comparison of the design of this internal manifold vs the external one. I don't profess to know which flow is better, but I am certainly not going to be convinced by "it just is" from random dude on the internet. Especially since there are other B58 models with the 6 port that generates lower performance.

Lets just leave it as we agree to disagree...

Can you SEE the difference in the two configurations?

The head with the integrated exhaust ports forces the exhaust stream to make sharp bends prior to exiting the head into the 2 port exhaust manifold, thereby restricting flow. The six port head doesn't. As such, the 6 port's flow stream is much smoother, less restrictive and therefore more efficient.

And what do you mean by "stronger steel manifold?"

The 6 port exhaust manifold it STEEL!

Can you show me cases where the 6 port manifolds are breaking?

https://www.wardsauto.com/10-best-engines-propulsion-systems/yet-another-spectacular-6-cyl-turbo-bmw

 

[harddrivin1le]

Genuinely interesting, but not sure how it relates to the quote.

That said, wasn't it part of the announcement that the 2021 Supra is more powerful and accelerates faster?

It shows (using Hale's formula) that the 2021 Supra's engine is at least 50 HP more powerful than the 2020 engine - at the crank.

Do you think BMW specified a less efficient (yet more costly) exhaust system in order to achieve that gain?

The 2021's engine's exhaust system is much more efficient because the flow transition radii are much larger. As such, they're less restrictive.

Also, the 2021 Supra's (and M340i's) exhaust manifold is STEEL.

 

[Reppunkamui]

Can you SEE the difference in the two configurations?

The head with the integrated exhaust ports forces the exhaust stream to make sharp bends prior to exiting the head into the 2 port exhaust manifold, thereby restricting flow. The six port head doesn't. As such, the 6 port's flow stream is much smoother, less restrictive and therefore more efficient.

And what do you mean by "stronger steel manifold?"

The 6 port exhaust manifold it STEEL!

Can you show me cases where the 6 port manifolds are breaking?

I think there are some reading/comprehension/confusion issues:

Once again, can't see the internal piping of the internal manifold in the picture, so it isn't as cut and dry as you mentioned. Once again, my original post was not about exhaust flow.

Once again yes, by stronger steel I mean the external exhaust manifold. The aluminium alloy engine block internal manifold is not as strong. Once again, I said this is why I believe the 6 port configuration is for more powerful applications.

No, there are no cases showing breaking manifolds because ^^^.

I can see both sides of the coin... I am not saying one is better or worse, I can see why they designed each engine the way they did and the advantages and disadvantages of the differences. Please read through my posts carefully, I am attempting to discuss not argue, "why my dad is better than your dad".

It shows (using Hale's formula) that the 2021 Supra's engine is at least 50 HP more powerful than the 2020 engine - at the crank.

Do you think BMW specified a less efficient (yet more costly) exhaust system in order to achieve that gain?

The 2021's engine's exhaust system is much more efficient because the flow transition radii are much larger. As such, they're less restrictive.

Also, the 2021 Supra's (and M340i's) exhaust manifold is STEEL.

Why do we need Hale's formula and the assumption that B58d is identical to the B58O1 to show a hp difference, when the 2021 Supra announcement literally tells us there is a 47 hp difference?

Performance is made up of many more factors than exhaust flow. I believe it the majority of the performance is due to tuning higher boost being run (without the risk of knocking), because of the higher pressure fuel injection, improved cooling, lower compression ratio and stronger exhaust manifold.

Once again, reread my posts, I have said the exhaust manifold was steel from the start...

This is just exhausting TBH...

 

[harddrivin1le]

I think there are some reading/comprehension/confusion issues:

Once again, can't see the internal piping of the internal manifold in the picture, so it isn't as cut and dry as you mentioned. Once again, my original post was not about exhaust flow.

Once again yes, by stronger steel I mean the external exhaust manifold. The aluminium alloy engine block internal manifold is not as strong. Once again, I said this is why I believe the 6 port configuration is for more powerful applications.

No, there are no cases showing breaking manifolds because ^^^.

I can see both sides of the coin... I am not saying one is better or worse, I can see why they designed each engine the way they did and the advantages and disadvantages of the differences. Please read through my posts carefully, I am attempting to discuss not argue, "why my dad is better than your dad".



Why do we need Hale's formula and the assumption that B58d is identical to the B58O1 to show a hp difference, when the 2021 Supra announcement literally tells us there is a 47 hp difference?

Performance is made up of many more factors than exhaust flow. I believe it the majority of the performance is due to tuning higher boost being run (without the risk of knocking), because of the higher pressure fuel injection, improved cooling, lower compression ratio and stronger exhaust manifold.

Once again, reread my posts, I have said the exhaust manifold was steel from the start...

This is just exhausting TBH...

Sudden bends in an exhaust system [as is the case with 2020 Supra engine] are inefficient because they compromise gas momentum and introduce turbulence. As such, the K (total resistance) factor increases, which means less efficient flow:

https://www.pipeflowcalculations.com/pipe-valve-fitting-flow/compressible-gas-flow.xhtml

Gradual bends are always preferable, assuming packaging constraints (e.g., available engine compartment space) permit. Gradual bends combined with idealized length/diameter ratios form the basis of proper exhaust (and intake) system design.

The 2021 Supra uses the existing M340i engine (including aluminum block and steel exhaust manifold). Are you aware of a single case where that combination has proved problematic? If not, why do you continue to mention it?

Indeed, the 2020 Supra engine also uses an aluminum block and steel exhaust manifold.

The 2021 engine almost certainly does rely on higher boost pressures. It will also burn more fuel (thereby expelling more exhaust) at wide open throttle, making a more efficient exhaust system that much more important.

 

[geert.bieseman]

Just wait and see people.
Everybody is still forgetting that Europe is not getting this engine due to regulations (and most likely the rest of the world neither)

Tune your engine, crank up that horsepower and enjoy.
Who will own a Supra and keep it at its default configuration... most likely nobody here, else you were not on this forum.

And the ones who do, wouldn't care less... as they will not even use the 340HP.

 

[harddrivin1le]

Just wait and see people.
Everybody is still forgetting that Europe is not getting this engine due to regulations (and most likely the rest of the world neither)

Tune your engine, crank up that horsepower and enjoy.
Who will own a Supra and keep it at its default configuration... most likely nobody here, else you were not on this forum.

And the ones who do, wouldn't care less... as they will not even use the 340HP.

One wonders what those regulations are, given that the BMW M340i uses the very same same engine as the 2021 US market Supra, yet is sold in Europe. While the Z4 M40i uses a very slightly different variation (higher compression ratio and presumably less peak boost), it's also sold in Europe.

Why would those engines meet European regulations when installed in BMWs, but not meet them if installed in the Supra?

 

[geert.bieseman]

One wonders what those regulations are, given that the BMW M340i uses the very same same engine as the 2021 US market Supra, yet is sold in Europe. While the Z4 M40i uses a very slightly different variation (higher compression ratio and presumably less peak boost), it's also sold in Europe.

Why would those engines meet European regulations when installed in BMWs, but not meet them if installed in the Supra?

Most likely model introduction year.
Else the European Z4 would have the same engine as the American one (since their introduction)

 

[harddrivin1le]

Most likely model introduction year.
Else the European Z4 would have the same engine as the American one (since their introduction)

Could be, though I'm inclined to think it's marketing related.

Either way, expect the USA 2021 Supra's [edit: inline six version's] quarter mile trap speed to be some 5 - 6 MPH faster than the 2020 model. It'll be close up until 70 MPH or so, given lower speed acceleration is compromised by traction limitations. But at elevated speeds, the 2021 car will be decisively faster.

It'll be interesting to see if EPA MPG ratings remain the same. I suspect they will be, given the ~ 150 pound heavier BMW Z4 M40i matches the Supra's ratings.

Sponsored