Roadfly.com         Roadfly Home | Features | Car Review Videos | Car Reviews | Cars For Sale | Used Car Parts Classifieds | Forum | Car Review Archives | Forum Archives Index



PDA



Marko
11-27-2000, 12:46 PM
From Car And Driver Dec. 20000.Click the pictures more than once to enlarge to read article.

M3Mike
11-27-2000, 01:01 PM
I read the article and it explains why the M3s are at a (power)disadvantage to the 911s. Both motors, the M3's 3.2 and the 911's 3.6, fall into the same size class under the ALMS rules. This means that both motors get the same size intake restrictor plates. This is a severe disadvanatge for the M3 which makes most of its power in the high revs where the air supply to the motor matters most. The 911, with its bigger motor, can make a lot of torque in the low revs where it doesn't need to suck in that much air. Bottom line: Each car should have a restrictor plate that is relative in size to the size of the motor.<p>Comments welcome.<br>Mike<p><i><br>From Car And Driver Dec. 20000.Click the pictures more than once to enlarge to read article.<p></i><br>

Marko
11-27-2000, 01:12 PM
<i><br>I read the article and it explains why the M3s are at a (power)disadvantage to the 911s. Both motors, the M3's 3.2 and the 911's 3.6, fall into the same size class under the ALMS rules. This means that both motors get the same size intake restrictor plates. This is a severe disadvanatge for the M3 which makes most of its power in the high revs where the air supply to the motor matters most. The 911, with its bigger motor, can make a lot of torque in the low revs where it doesn't need to suck in that much air. Bottom line: Each car should have a restrictor plate that is relative in size to the size of the motor.<p>Comments welcome.<br>Mike<p><br>From Car And Driver Dec. 20000.Click the pictures more than once to enlarge to read article.<p><br></i><br>

M3Mike
11-27-2000, 01:26 PM
the current block is bored to it's limits. increasing engine size (by going to a new block) will also increase weight and the larger,heavier pistons may reduce the ability of the engine to rev so high. I would love to see the M3s beet the 911s with a smaller engine. If only they had a less restrictive restrictor plate.<br>Oh well, they didn't do too bad for their first year anyway. Now that BMW will not be running the prototypes next season, maybe the M3s will get more attenton and be more competitive.<br>

Marko
11-27-2000, 01:44 PM
<i><br>the current block is bored to it's limits. increasing engine size (by going to a new block) will also increase weight and the larger,heavier pistons may reduce the ability of the engine to rev so high. I would love to see the M3s beet the 911s with a smaller engine. If only they had a less restrictive restrictor plate.<br>Oh well, they didn't do too bad for their first year anyway. Now that BMW will not be running the prototypes next season, maybe the M3s will get more attenton and be more competitive.<p></i><br>

M3Mike
11-27-2000, 02:36 PM
<i><br>V8's are already in the cars<br>That they should use the V8 now and not wait till later to bring it out. The V8 weighs less then the Iron block six and produces more tq and more hp.<p><br></i><br>

Will
11-27-2000, 03:00 PM
<i> That the motor in the car featured was the s52 ans not the new s54?

Will
11-27-2000, 03:00 PM
<i> That the motor in the car featured was the s52 and not the new s54?

James
11-27-2000, 03:53 PM
Yes very strange. The displacement is the same as the new (s54) motor but it is clearly the older euro motor as evidenced by it's cylinder head cover and other casting marks on the side of the head (newer motor is smooth). Wonder what this signifies.....<br>

Paul
11-27-2000, 04:05 PM
<i><br> That the motor in the car featured was the s52 ans not the new s54?<p></i><p>The article says "The M3 racer uses the same engine that's in the new 2001 M3, and both powerplants have the same bore and stroke."<p>It goes on to say the cams are unique and "PTG also replaces the stock pistons and connecting rods with stronger but lighter pieces that can survive the 8250-rpm limit. These changes netted an additional 87 horsepower over the standard M3 engine for a total of 420 at 8200 rpm."<br>

24 hours of Daytona. Rich
11-27-2000, 04:06 PM
<i><p>V8's are already in the cars<br>That they should use the V8 now and not wait till later to bring it out. The V8 weighs less then the Iron block six and produces more tq and more hp.<p><br></i><br>

Psyence
11-27-2000, 04:48 PM
The engine needs new pistons and con-rods to take an additional 250 RPM over what will be the stock rev limit? And this is for a race engine that probably only needs to survive a couple of races before being torn down?<p>I can see why they are having production problems...<p>I'd also be interested in how they got 87 more HP out of the engine at only 300 more RPM than the stock engine's supposed peak output RPM. Are they running a crazy *** cam or something?

David
11-27-2000, 05:04 PM
I'd also be interested in how they got 87 more HP out of the engine at only 300 more RPM than the stock engine's supposed peak output RPM. Are they running a crazy *** cam or something?<p></i><br>

M3Mike
11-27-2000, 05:17 PM
<i><p>V8's are already in the cars<br>That they should use the V8 now and not wait till later to bring it out. The V8 weighs less then the Iron block six and produces more tq and more hp.<p><br></i><br>

Mr. Grinch
11-27-2000, 05:24 PM
Vanos simply isn't enough. It can change the timing and duration of the valve openings, but what it can't do is change the distance they open. New cams were used, as reported in the article, and you can rest assured they have more lift than factory.

Mr. Grinch
11-27-2000, 05:26 PM
Hamman / Hartge and others have already taken the block to 3.4. Can it be done? Certainly. Will it last a race? That remains to be seen.<br>

James
11-27-2000, 06:33 PM
...and extensive flow porting of the cylinder head would easily result in this type of modest power increase. Remember they said the pistons were not stock thus it goes to reason they are of higher compression. What people should be concerned with is that this is the M-52 vice the M-54 motor base thus this car's motor is not representative of the new motor in any way.

M3Mike
11-27-2000, 07:38 PM
how will changing the gear ratios increase the engines overall ability to make power. changing the gear ratios may give you better accelaration out of corners, but you will lose top end speed, where the M3s are already lacking (compared to the P-cars at least). First gear is almost never used anyway.<p><br>the current block is bored to it's limits. increasing engine size (by going to a new block) will also increase weight and the larger,heavier pistons may reduce the ability of the engine to rev so high. I would love to see the M3s beet the 911s with a smaller engine. If only they had a less restrictive restrictor plate.<br>Oh well, they didn't do too bad for their first year anyway. Now that BMW will not be running the prototypes next season, maybe the M3s will get more attenton and be more competitive.<p><br></i><br>

KJK
11-27-2000, 07:43 PM
<i>with software and CAI. <br> <p>It goes on to say the cams are unique and "PTG also replaces the stock pistons and connecting rods with stronger but lighter pieces that can survive the 8250-rpm limit. These changes netted an additional 87 horsepower over the standard M3 engine for a total of 420 at 8200 rpm."<p></i><br>

Mr. Grinch
11-27-2000, 08:12 PM
So given you're info above, which I agree with, what do you think? Just curious where you're going with this.<br>

James
11-27-2000, 08:23 PM
What I'm getting at is that BMW racing apparently did not feel that the new engine was ready for prime time in their M3 racing car. Otherwise they would have used it - right?!?! Someone for some reason made the decision to use the M-52 engine in the e46 based M3 race car. Why? Your guess is as good as mine. Reliability issues, familiarity issues or lack of available parts. We will find out eventually.<br>

Evan...(more)
11-27-2000, 08:30 PM
</i>That they should use the V8 now and not wait till later to bring it out. The V8 weighs less then the Iron block six and produces more tq and more hp.<br>

Mr. Grinch
11-27-2000, 08:36 PM
We might never know for certain? They could switch to the new engine with no mention at all... or perhaps never switch!<p>But if it were _me_ bringing a new car into a race series, and if I had the time and money option of optimizing one variable at a time, I might lean towards that. IE optimize the new chasis with a known factor (engine) then once it's sorted out, introduce the other unknown (engine). But it sounds like the chassis is everthing they'd hoped for and needs very little work. Sounds like all their work lies in engine / drivetrain. <p><br>

James
11-27-2000, 08:42 PM
Agreed, the M-52 was a well known quantity and only a few HP less than the new motor in street trim. It may also have been easier to modify for racing purposes due to it's widespread availability.

Paul
11-27-2000, 09:29 PM
If dropping in the 4.9L V8 results in a lighter, more powerful, and proven (M5/Z8) result, why did BMW go to the trouble of creating a brand new 6 that is heavier, less powerful, and needs much time and money to develop which appears to be an effort still in progress?<p>Do not tell me it is because cheaper BMWs cannot be faster than more expensive ones. That rule is broken throughout the BMW line.<p>There should be a reasonable explanation that is not obvious.<br>

Psyence
11-27-2000, 10:22 PM
Don't tell me you're still buying that the engine is "brand new".<p>Seriously now.<p><i><br>If dropping in the 4.9L V8 results in a lighter, more powerful, and proven (M5/Z8) result, why did BMW go to the trouble of creating a brand new 6 that is heavier, less powerful, and needs much time and money to develop which appears to be an effort still in progress?<p>Do not tell me it is because cheaper BMWs cannot be faster than more expensive ones. That rule is broken throughout the BMW line.<p>There should be a reasonable explanation that is not obvious.<p></i><br>

Mr. Grinch
11-28-2000, 12:14 AM
Put them in more X5s?<p>heh heh!<br>

Randy G
11-28-2000, 01:19 AM

Dave
11-28-2000, 04:08 AM
Don't forget the addition of technology behind special dome shapes on the pistons designed to provide a better burn. This technology is being applied to Hondas where they can run 12:1 compression on pump gas. More interesting stuff at: <p><i><br>...and extensive flow porting of the cylinder head would easily result in this type of modest power increase. Remember they said the pistons were not stock thus it goes to reason they are of higher compression. What people should be concerned with is that this is the M-52 vice the M-54 motor base thus this car's motor is not representative of the new motor in any way.<p></i><br>

That would make the M3's smaller
11-28-2000, 09:55 AM
<i><br>I read the article and it explains why the M3s are at a (power)disadvantage to the 911s. Both motors, the M3's 3.2 and the 911's 3.6, fall into the same size class under the ALMS rules. This means that both motors get the same size intake restrictor plates. This is a severe disadvanatge for the M3 which makes most of its power in the high revs where the air supply to the motor matters most. The 911, with its bigger motor, can make a lot of torque in the low revs where it doesn't need to suck in that much air. Bottom line: Each car should have a restrictor plate that is relative in size to the size of the motor.<p>Comments welcome.<br>Mike<p><br>From Car And Driver Dec. 20000.Click the pictures more than once to enlarge to read article.<p><br></i><br>

NY
11-28-2000, 10:57 AM
You tool, dont get so technical. I think we all know what he meant. Smaller restrictor meaning larger opening (less restrictive).<br> <br>I read the article and it explains why the M3s are at a (power)disadvantage to the 911s. Both motors, the M3's 3.2 and the 911's 3.6, fall into the same size class under the ALMS rules. This means that both motors get the same size intake restrictor plates. This is a severe disadvanatge for the M3 which makes most of its power in the high revs where the air supply to the motor matters most. The 911, with its bigger motor, can make a lot of torque in the low revs where it doesn't need to suck in that much air. Bottom line: Each car should have a restrictor plate that is relative in size to the size of the motor.<p>Comments welcome.<br>Mike<p><br>From Car And Driver Dec. 20000.Click the pictures more than once to enlarge to read article.<p><br></i><br>

M3Mike
11-28-2000, 11:05 AM
The reason the M3s are delayed is because BMW is waiting for the 2000 ALMS season to end so that they can put the used V12 from the prototypes in the M3s. The engines produce 95,000 horsepower and will last 350 miles. They will also silence all the fools who want a V8 in the M3.<br>LOL<p><br>Put them in more X5s?<p>heh heh!<p></i><br>

Rich M3
11-28-2000, 01:50 PM
V8's are already in the cars<i><br>That they should use the V8 now and not wait till later to bring it out. The V8 weighs less then the Iron block six and produces more tq and more hp.<p></i><br>


Roadfly Home | Car Reviews | Forum Archives Index