MX3 1.8L V-6

Recently GM just introduced a new truck (the name of which escapes me)
and it's a smaller one...the replacement for the S10, and has a 4
cylinder and a 5 cylinder engine. A 5 cylinder engine from the
General? The claim is that it's the perfect size, and they couldn't
fit a 6 in there.

I say that the main reason is that they didn't want to make a 6 to fit
there...and it probably was easier to expand a 4 with an extra
cylinder...and convince US buyers that a 5 cylinder is a perfectly
good engine.

Having said all that (and it's actually slitghtly irrelevant)
conversation with a friend came up concerning this and the MX3's
little V6. Clearly it's possible to make such an engine, and everyone
seemed to rave about it, but no automaker is persuing little V6's.
That indicates to me that there must have been some huge problem with
the design that lead to even Mazda dropping it. But I can't find info
anywhere...thoughts?

You are thinking of Mazda's KL series v-6 engines. It was made in several
different versions from 1.8 liter to 2.5 liter. They won a bunch of awards
when they were introduced and actually it is a very good engine.

I don't know exactly why Mazda discontinued it but I suspect it has to do
with the development of the harmonic balance shaft and variable valve timing
technologies. The first allowed a four cylinder engine to run nearly as
smoothly as a 6 cylinder engine and the second allowed the same four
cylinder to deliver a higher specific output.

If you stop and think for a minute, you will see that it is easier and
cheaper to add these technologies to a four cylinder engine and develop a
car around this "modern" 4 cylinder than a comparable 6 cylinder. The 4
cylinder also allows for greater flexibility in installation since it takes
up little space.

The other thing that might contribute to the demise of the KL series is that
it was designed to be installed leaned over to the side. This made
packaging in a small front wheel drive car easier. But it also meant that
all the oil passages and such like are arranged to support this angled
installation. The only things I have found talking about trying to mount
this engine upright have discussed poor oil distribution. This pretty much
precluded the installation in an upright position and made a longitudinal
mounting difficult.

I don't know if any of this answers your questions or just raises new ones.
Remember this is my speculation so take it for what it is worth. By the
way, one of my cars is a 93 MX-6 V-6 which is one of the cars that used the
2.5 liter version of the KL. I bought it new in May of 92. It is my
version of a sporty utility vehicle and I still love the thing. It is not
as much fun and frisky as my Miata but then the Miata doesn't carry four
people or bicycles inside.

links you might like to read:
http://homepage.ntlworld.com/dorothy...bemx/p_m18.htm
http://mx6.com

For what it's worth.
--
Michael and Paula Whitehouse
Cielo, 10AE # 511

"james" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> Recently GM just introduced a new truck (the name of which escapes me)
> and it's a smaller one...the replacement for the S10, and has a 4
> cylinder and a 5 cylinder engine. A 5 cylinder engine from the
> General? The claim is that it's the perfect size, and they couldn't
> fit a 6 in there.
>
> I say that the main reason is that they didn't want to make a 6 to fit
> there...and it probably was easier to expand a 4 with an extra
> cylinder...and convince US buyers that a 5 cylinder is a perfectly
> good engine.
>
> Having said all that (and it's actually slitghtly irrelevant)
> conversation with a friend came up concerning this and the MX3's
> little V6. Clearly it's possible to make such an engine, and everyone
> seemed to rave about it, but no automaker is persuing little V6's.
> That indicates to me that there must have been some huge problem with
> the design that lead to even Mazda dropping it. But I can't find info
> anywhere...thoughts?

Your assumption on the new GM 5 cylinder engine is wrong. The new 5, and 4,
cylinder truck engines are actually based on the fairly new inline 6
cylinder that GM puts in the Trailblazer and Envoy. That 6 cylinder, by the
way, has been getting generally rave reviews.

John ('94 Miata)

"james" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> Recently GM just introduced a new truck (the name of which escapes me)
> and it's a smaller one...the replacement for the S10, and has a 4
> cylinder and a 5 cylinder engine. A 5 cylinder engine from the
> General? The claim is that it's the perfect size, and they couldn't
> fit a 6 in there.
>
> I say that the main reason is that they didn't want to make a 6 to fit
> there...and it probably was easier to expand a 4 with an extra
> cylinder...and convince US buyers that a 5 cylinder is a perfectly
> good engine.
>
> Having said all that (and it's actually slitghtly irrelevant)
> conversation with a friend came up concerning this and the MX3's
> little V6. Clearly it's possible to make such an engine, and everyone
> seemed to rave about it, but no automaker is persuing little V6's.
> That indicates to me that there must have been some huge problem with
> the design that lead to even Mazda dropping it. But I can't find info
> anywhere...thoughts?

One GREAT advantage of the inline over a V configuration is ONE
exhaust manifold and ONE head, also in the event of overhead cam(s)
the single head means less cams and less complex belt or chain systems
to drive those cams....so construction is simpler as is working on one
for the owner. I'd always prefer an inline engine over a Vee for the
ease of maint......:>)

Tom....w/a new '03 ready for first oil change....4XX miles :>)



(E-Mail Removed) (james) wrote in message news:<(E-Mail Removed). com>...
> Recently GM just introduced a new truck (the name of which escapes me)
> and it's a smaller one...the replacement for the S10, and has a 4
> cylinder and a 5 cylinder engine. A 5 cylinder engine from the
> General? The claim is that it's the perfect size, and they couldn't
> fit a 6 in there.
>
> I say that the main reason is that they didn't want to make a 6 to fit
> there...and it probably was easier to expand a 4 with an extra
> cylinder...and convince US buyers that a 5 cylinder is a perfectly
> good engine.
>
> Having said all that (and it's actually slitghtly irrelevant)
> conversation with a friend came up concerning this and the MX3's
> little V6. Clearly it's possible to make such an engine, and everyone
> seemed to rave about it, but no automaker is persuing little V6's.
> That indicates to me that there must have been some huge problem with
> the design that lead to even Mazda dropping it. But I can't find info
> anywhere...thoughts?