a question for you tech heads out there

[nugent]

our m5 has a 4.4 L V8. AMG 63s have a 6.3L V8. more displacement, more torque, lower redline. why does bmw choose smaller engines vs. MB? one reason i can think of is smaller engines have a bigger rev-range, which would make power modulation and thus control more manageable. this translates to better handling and a faster car when direction changes are needed. any other thoughts?

[JOHNBMWM5]

Originally Posted by nugent

our m5 has a 4.4 L V8. AMG 63s have a 6.3L V8. more displacement, more torque, lower redline. why does bmw choose smaller engines vs. MB? one reason i can think of is smaller engines have a bigger rev-range, which would make power modulation and thus control more manageable. this translates to better handling and a faster car when direction changes are needed. any other thoughts?

Mercedes have dropped the 6.2 in favour of a V8 4.4, NO more 6.2 made sorry.

[Dumbo]

Originally Posted by johnbmw6

Mercedes have dropped the 6.2 in favour of a V8 4.4, NO more 6.2 made sorry.

The new AMG motor is 5.5l. Except in the SLS and current gen c63

Still 25% larger.

[emmfive]

The E63 went to a 5.5 litre turbo in 2010 when the body style changed.

[RPiM5]

Originally Posted by chrisratz

The E63 went to a 5.5 litre turbo in 2010 when the body style changed.

^^^ This.

That said, although their 5.5L Twin Turbo V8 Engine is 1.1L larger, they also still have their turbo's mounted on the flanks. Our S63tu engines are optimized for drastic reductions in Turbo Lag, Mercedes AMG's are not. Additionally, although the Mercedes engines have a nice exhaust note, because they are a larger discplacement engine and have the traditional combustion flow through the engine giving them their signature AMG throaty, rumble, and roar; I like our S63tu's better. We have the cross manifold, flat crank-ish sound, which is more similar to a Ferarri sound than a big Mustang V8 sound. I think the S63tu sounds way more exotic, especially when straightpiped.

[nugent]

Originally Posted by RPiM5

^^^ This.

That said, although their 5.5L Twin Turbo V8 Engine is 1.1L larger, they also still have their turbo's mounted on the flanks. Our S63tu engines are optimized for drastic reductions in Turbo Lag, Mercedes AMG's are not. Additionally, although the Mercedes engines have a nice exhaust note, because they are a larger discplacement engine and have the traditional combustion flow through the engine giving them their signature AMG throaty, rumble, and roar; I like our S63tu's better. We have the cross manifold, flat crank-ish sound, which is more similar to a Ferarri sound than a big Mustang V8 sound. I think the S63tu sounds way more exotic, especially when straightpiped.

thanks for actually answering my question.

[stealth.pilot]

Originally Posted by Dumbo

The new AMG motor is 5.5l. Except in the SLS and current gen c63

Still 25% larger.

You're right. So who's the dumbo on the thread!

Just kidding nugent!

[nugent]

Originally Posted by stealth.pilot

You're right. So who's the dumbo on the thread!

Just kidding nugent!

true, but the spirit of the question still stands. why is bigger not necessarily better?

[emmfive]

Originally Posted by nugent

true, but the spirit of the question still stands. why is bigger not necessarily better?

I should have mentioned in my earlier "mr smarty pants" post- its a good question and I'm going to follow the thread to see the responses!

[mwlmd]

Originally Posted by nugent

true, but the spirit of the question still stands. why is bigger not necessarily better?

Here is what I don't understand. BMW uses a SMALLER displacement engine with 2 turbos vs AMG but AMG manages to avoid the GGT. That seems like an engineering fail for BMW.

[stealth.pilot]

Originally Posted by nugent

true, but the spirit of the question still stands. why is bigger not necessarily better?

I don't know if bigger isn't better. High rpm limit is nice for sound reasons but I don't see why you can't have that with more displacement. The V10 was 5l and had a higher rpm limit than our 4.4l.

The AMG engine in S form has more HP, more torque, and better fuel efficiency than our 4.4l. There's no gas guzzler tax on the E63AMG and I don't know about the S-AMG version but Mercedes was saying they hoped to avoid gas guzzler on that too.

[RPiM5]

Originally Posted by mwlmd

Here is what I don't understand. BMW uses a SMALLER displacement engine with 2 turbos vs AMG but AMG manages to avoid the GGT. That seems like an engineering fail for BMW.

I don't know how the AMG 5.5L TT V8 manages its fuel or if it really is in fact better, but I do know that the U.S. EPA is the one who determines a GGT based on their assesments of MPG. It could be that the AMG engine really is more fuel efficient or maybe Mercedes paid the EPA to make the BMW engines have a GGT. I'm too lazy to research this right now. Lol!

[nugent]

Originally Posted by mwlmd

Here is what I don't understand. BMW uses a SMALLER displacement engine with 2 turbos vs AMG but AMG manages to avoid the GGT. That seems like an engineering fail for BMW.

maybe MB has more lobbyists at the EPA

[JOHNBMWM5]

Originally Posted by Dumbo

The new AMG motor is 5.5l. Except in the SLS and current gen c63

Still 25% larger.

Yes corrected.

[JOHNBMWM5]

On a side note: I sat in my mate next doors New Mercedes to test the tech, and it's light years behind BMW's.