BARMY

My MSM will be rebuilt shortly including a forged bottom end, stronger valve springs, uprated clutch, coolant reroute and bigger rad, bigger injectors and stand alone ECU.

The builder is advising me against using it as my DD because, he says, doing so will cause undue wear.

The drive to work is less than 5 minutes and is low speed and requires very little throttle. Yes, I can sometimes walk or cycle to work by the way, but I still want to try to avoid owning a second car if possible.

So can I safely use the MSM for these short trips without significantly accelerating the wear on the motor?

I don't like the idea of running a motor with no load but is there maybe a middle ground involving warming the motor up before setting off?

carnut169

The old don't use it as you'll wear it out philosophy.

I prefer the I built it to use it philosophy. It reminds me of the analogy about not sleeping w/ a girlfriend so her next partner will have a better experience.

ctdrftna

iTrader: (1)

if its wearing out because of less load, your engine builder sucks. yes you will put milage and wear on it. But as long as your not boosting to redline between every stop light your should be fine. Allow the car to warm up and be nice to it

BARMY

Was hoping to hear similar to this.
Others have told me load on a motor is way less when ticking over at 950-1,250rpm than when under even a low load at 2,000-3,000rpm.
So presently planning to let it tick over to warm up for a few minutes before driving to and from work.
Even if I have to refresh the motor ever 2-3 years this is still cheaper than having a company car with the attendant loss of car allowance and increase in fringe benefit tax. And I get to drive my MX5 instead of maybe a Mazda 6.

BARMY

Gotcha and thanks. I will warm it up at least for a few minutes. There will be no redlining on the way to or from work, or even on the road at all. That'll only happen on the track and after a more thorough warm up.

Savington

iTrader: (31)

The issue isn't with your motor or your builder - it's with your commute. Engines receive most of their wear when they're cold, so if you only drive it 5 miles a day, it's going to get a lot of wear put on it in a short period of time. A single 50 mile trip wears the engine less than two 5-mile trips with 8 hours of rest in between them.

Warming up the motor before setting off is even worse - it spends more time at colder coolant temps and wears more. The best thing you can do for a motor is to start it and set off immediately using light-moderate throttle to warm it up as quickly as possible without abusing it when it's cold.

Erat

iTrader: (5)

Also it spend more time in a "enriched" state when it's cold which has it's own set of issues that will contribute to more wear.

krissetsfire

iTrader: (1)

regardless of these facts i laughed when i read it.

Why own something if you're not going to use it? Built or not built why would you bother not using it. Regardless of the forged internals the wearing factor is the same or close to something that was intended to be daily driven.

There are a few things a builder could do when building that would effect the wear but if he built it to oem spec then wtf. That's like the salesman at the car dealer telling you not to daily drive the car you jut bought. The motor is within OEM spec and will wear similarly to how it normally would.

I don't personally like walking by and glancing at things ive purchased.

Imagine buying a tv 100" plasma and only turning it on once in a while because you were worried about the life of the tv being affected by how much you watch it. You never said this was a racecar. If you don't watch a lot of tv then why'd you buy the 100"? nah wha I mean breh?

Jeffbucc

This make me happy that I'll only drive the motor on nice warm days, and the Jetta on cold days. The diesel takes forever to warm up so it is a wash on "wear" regardless.

Full_Tilt_Boogie

iTrader: (1)

The only reason it wears any faster is because forged pistons expand more with temperature than a comparable cast or hypereutectic piston. In other words, while the engine is cold it is going to have a large P2W clearance and if you dont keeps the revs low you will get piston slap and aggressive wear.

Just keep the revs low until it warms up and it will be fine. It may not go hundreds of thousands of miles before it needs a rebuild, but its not going to need constant rebuilding or anything.

ctdrftna

iTrader: (1)

I think that chart is bogus. @180 degrees is saying your wearing roughly .0006 every 60 hours, pretty much at my 35min drive to and from work i would wear .0035 in a year roughly. That would double my P to W clearance. Thats absurd, maybe heavy loading at 7k on the dyno. Highly inaccurate wear for a daily driven car built or not.

Full_Tilt_Boogie

iTrader: (1)

IIRC that chart was made by some OEM testing (I almost want to say Chrysler for some reason) and it was with the engine held at high rpm.

Impuls

iTrader: (1)

I daily mine. Practically the same set up you want.
Forged, fully balanced rotating assembly
Ported polished head
Reroute
ID1000s
Megasquirt
ACT 6puck w/ extreme pressure plate for +400ft lbs of glory.


Don't use for short trips, just ride a bike. Environment!

I'm looking into buying a remote start as soon as DIYautotune sucks it up and admits that my Megasquirt idle control valve circuits are ******* and they need to replace it.
Just so I let the car warm up instead of having tutti leave early for anything.

bikersam717

iTrader: (5)

What's the consensus on a stock motor? My commute to work is 1 mile, the car never even warms up fully on cold mornings unless I start it 10 minutes before I leave. What is the preferred method?

krissetsfire

iTrader: (1)

That is highly dependent on pistons. Supertech uses materials with minimal expansion. So does mahle.... regardless and too the point if you read the OPs original post it sounds like hes considering or concerned about severe wear based on daily driving. It's just not going to happen. Some schmuck on his high horse playing know it all.

Drive the bitch and enjoy!

krissetsfire

iTrader: (1)

I commute to work about 1.5 miles. I don't ride my bike because I do use it for travel on occasion if the company cars are checked out. Just let it warm up some and keep the rpm's reasonable.

Fun fact. If you live that close to work starting it drains more on the battery then the alternator can replenish. My batteries weren't lasting as long when I moved to this location. I used to live 20 mins away. Put it on a trickle charge and now my batteries last longer than a year.

BARMY

Thanks for all the thoughts.

The car will do way more miles at the track and on the way to tracks than it will on the short commute to work.

I've worked out that it would be cheaper to have the bottom end rebuilt every couple of years than to take the option of a company car. So the decision is taken to use it as a DD.

It would now be good to know whether to warm up or not to warm up as there appears to be plenty of conflicting evidence and opinion. Perhaps the fact that the pistons are Supertech might result in more consistent opinions?

turbofan

iTrader: (1)

Not to hang off his ***** or anything but I would go with Savington's advice. Guy knows how to build and use motors.

Also: You won't have to rebuild the engine every couple of years. Many guys here get 70-80k miles or even more out of their built engines (viperormiata got over 100k boosted miles, as one example).

nitrodann

Sav, forces on bearing go up exponentially with rpm, how does that factor into your , 'drive it easy instead of idle' warm up ideas?

Also, it matters not that 2x 5 minute drives wear more than a single 50 mile drive, if you drive to work and back each day you are doing 2x5 minute cold drives regardless.

Dann

NiklasFalk

iTrader: (1)

Block heater...


If you really worry that much.