325 vs. 328, is there a difference in reliability?

On Wed, 12 Oct 2005 12:01:01 -0700, "Jeff Strickland"
> wrote:

>"dizzy" > wrote in message
>news
>> On Tue, 11 Oct 2005 18:13:31 -0700, "Jeff Strickland"
>> > wrote:
>>
>>>"dizzy" > wrote in message
...
>>>> On Mon, 10 Oct 2005 08:00:14 -0700, "Jeff Strickland"
>>>> > wrote:
>>>>
>>>>>The 328 is used in the E36 cars after 1996, the 325 is used in cars
>>>>>before
>>>>>'96. The 328 gives 1 more HP, but has about 30% more torque, give or
>>>>>take
>>>>>a
>>>>>few foot pounds.
>>>>
>>>> You sure about those numbers? I find it hard to believe that a motor
>>>> with only 12% more displacement could have 30% more torque, when they
>>>> are of similar design.
>>>>
>>>
>>>Wild but true. Perhaps the torque numbers are only better by 27%, but
>>>that's
>>>close enough.
>>>
>>>I want to be perfectly clear, the 328 does not have 30% more torque. The
>>>number is in that neighborhood, but I forget the precise number. I used
>>>"about" because I don't know the actual number. But it's a significant
>>>number.
>>
>> Well, I'm saying I don't believe it, without some evidence. The
>> Greene's numbers make sense to me. Torque is very proportional to
>> displacement.
>>
>>>I haven't done the math, but I suspect that 328 is not 12% greater than
>>>325.
>>>I've done the math now, and I was right, 328 is not 12% greater than 325.
>>>It's actually less than 1%.
>>
>> Ummm, try 2.8/2.5, and I think you'll see the 12% displacement
>> difference.
>
>As it turns out, we're both wrong.

Umm... No, I am not wrong. What was I wrong about? I challenged your
error, and I was correct.

>The increased torque in the 328 isn't
>27%, it's 27 ft pounds, or pound feet to be more correct.

Much better.

On Wed, 12 Oct 2005 13:28:02 -0700, "Jeff Strickland"
> wrote:

>
>"Tom K." > wrote in message
...
>>
>> "Jeff Strickland" > wrote in message
>> ...
>>>
>>> "dizzy" > wrote in message
>>> news >>>> On Tue, 11 Oct 2005 18:13:31 -0700, "Jeff Strickland"
>>>> > wrote:
>>>>
>>>>>"dizzy" > wrote in message
om...
>>>>>> On Mon, 10 Oct 2005 08:00:14 -0700, "Jeff Strickland"
>>>>>> > wrote:
>>>>>>
>>>>>>>The 328 is used in the E36 cars after 1996, the 325 is used in cars
>>>>>>>before
>>>>>>>'96. The 328 gives 1 more HP, but has about 30% more torque, give or
>>>>>>>take
>>>>>>>a
>>>>>>>few foot pounds.
>>>>>>
>>>>>> You sure about those numbers? I find it hard to believe that a motor
>>>>>> with only 12% more displacement could have 30% more torque, when they
>>>>>> are of similar design.
>>>>>>
>>>>>
>>>>>Wild but true. Perhaps the torque numbers are only better by 27%, but
>>>>>that's
>>>>>close enough.
>>>>>
>>>>>I want to be perfectly clear, the 328 does not have 30% more torque. The
>>>>>number is in that neighborhood, but I forget the precise number. I used
>>>>>"about" because I don't know the actual number. But it's a significant
>>>>>number.
>>>>
>>>> Well, I'm saying I don't believe it, without some evidence. The
>>>> Greene's numbers make sense to me. Torque is very proportional to
>>>> displacement.
>>>>
>>>>>I haven't done the math, but I suspect that 328 is not 12% greater than
>>>>>325.
>>>>>I've done the math now, and I was right, 328 is not 12% greater than
>>>>>325.
>>>>>It's actually less than 1%.
>>>>
>>>> Ummm, try 2.8/2.5, and I think you'll see the 12% displacement
>>>> difference.
>>>>
>>>
>>>
>>> As it turns out, we're both wrong. The increased torque in the 328 isn't
>>> 27%, it's 27 ft pounds, or pound feet to be more correct.
>>>
>>> I like Greene's numbers too.
>>>
>>
>> By Greene's numbers:
>> Displacement difference (rounded to 1/10 liter) is .3 liter, so .3/2.5 =
>> 12.0% increase.
>> Torque difference (207-181) is 26 lb. ft., so 26/181 = 14.4% increase.
>>
>> Increase is measured as a percentage of the starting figures; that is the
>> 2.5 liter engine.
>>
>> Tom
>
>Agreed. I originally said that the torque increase was 30%, it's really 30
>ft lb, and it's actually 26 ft lb. Dizzy might have been more right than me,
>but you'll never hear me admitting that, therefore we're both wrong.

I made no errors. I challenged what I saw was an obvious error on
your part, and I said that the torque difference in reality will
closely track the displacement difference.

You are making yourself look ridiculous with your claims that I was
wrong too.

Kyle and Lori Greene wrote:
> "dizzy" > wrote in message
> ...
>
>>On Mon, 10 Oct 2005 08:00:14 -0700, "Jeff Strickland"
> wrote:
>>
>>
>>>The 328 is used in the E36 cars after 1996, the 325 is used in cars before
>>>'96. The 328 gives 1 more HP, but has about 30% more torque, give or take
>>>a
>>>few foot pounds.
>>
>>You sure about those numbers? I find it hard to believe that a motor
>>with only 12% more displacement could have 30% more torque, when they
>>are of similar design.
>>
>
>
> Edmunds list the following....
>
> 95 325i HP 189 @ 5900 Torque 181 @ 4200
>
> 96 328i HP 190 @ 5300 Torque 207 @ 3950
>
> My math (which is subject to correction) gets about 12.5% more torque at 250
> RPM lower. I'm not certain, but I think I remember the torque band being
> wider on the 328 as well (starting to pull lower and continuing higher).
>
> Kyle.
> 98 740iL
> 97 M3
>

Actually the 2.8 makes less tourque at 5900 RPM than the 2.5. If it
made more than it would have more HP at that RPM then 2.5 does.
Remember HP is just a function of tourque and RPM. The 2.8s power band
is just lower and wider. The reason the 2.8 is so much faster than the
2.5 is because it makes a whole lot more tourque from 3-4K RPM. From
4-5K there isn't a whole lot of difference, the 2.8s a little bit
stronger. From 5-6K the 2.5 starts to catch up (by not having the power
fall off as much as the RPM climes).


--
========================================

Todd Zuercher


========================================

Todd Zuercher wrote:
> Actually the 2.8 makes less tourque at 5900 RPM than the 2.5. If it
> made more than it would have more HP at that RPM then 2.5 does.
> Remember HP is just a function of tourque and RPM. The 2.8s power band
> is just lower and wider. The reason the 2.8 is so much faster than the
> 2.5 is because it makes a whole lot more tourque from 3-4K RPM. From
> 4-5K there isn't a whole lot of difference, the 2.8s a little bit
> stronger. From 5-6K the 2.5 starts to catch up (by not having the power
> fall off as much as the RPM climes).

Well it's lower alright. I don't think the 2.8 is *so* much faster
than the 325/2.5.

In article .com>,
> wrote:
> Well it's lower alright. I don't think the 2.8 is *so* much faster
> than the 325/2.5.

It is in day to day driving.

--
*Oh, what a tangled website we weave when first we practice *

Dave Plowman London SW
To e-mail, change noise into sound.

I can definitely vouch on the torque advantage.

Did a test with a friend.
Me = 96 328is
him = 93 325is

We matched speeds going uphill around 3500rpm. Then we both floored
it. The 2.8 steadily pulled away on the hill and kept spooling. Test
lasted 10 seconds.

"Kyle and Lori Greene" > wrote:

>
>"dizzy" > wrote in message
.. .
>> On Mon, 10 Oct 2005 08:00:14 -0700, "Jeff Strickland"
>> > wrote:
>>
>>>The 328 is used in the E36 cars after 1996, the 325 is used in cars before
>>>'96. The 328 gives 1 more HP, but has about 30% more torque, give or take
>>>a
>>>few foot pounds.
>>
>> You sure about those numbers? I find it hard to believe that a motor
>> with only 12% more displacement could have 30% more torque, when they
>> are of similar design.
>>
>
>Edmunds list the following....
>
>95 325i HP 189 @ 5900 Torque 181 @ 4200
>
>96 328i HP 190 @ 5300 Torque 207 @ 3950
>
>My math (which is subject to correction) gets about 12.5% more torque at 250
>RPM lower. I'm not certain, but I think I remember the torque band being
>wider on the 328 as well (starting to pull lower and continuing higher).
>
>Kyle.
>98 740iL
>97 M3
>
>
>
>

BC wrote:
> I can definitely vouch on the torque advantage.
>
> Did a test with a friend.
> Me = 96 328is
> him = 93 325is
>
> We matched speeds going uphill around 3500rpm. Then we both floored
> it. The 2.8 steadily pulled away on the hill and kept spooling. Test
> lasted 10 seconds.
>


The 328 has different gearing to the old 325 I believe which will also
have an effect. The 328 has an extra 300cc so one would expect it to
be a little faster.
But how about this - if one bored out a 325 to 2.8l you'd get about
215hp out of it but woudl it be faster than the regular 328i??