Board logo

Block Lightening
Nosey - 22/12/13 at 06:47 PM

So, I am fitting a silver top Zetec into my hillclimber instead of my current C20XE (long story...). This is perfect at the minute but will probably need a rebuild in the next year or so. I have a spare block and access to a large milling machine and some free time. Would mounting up the spare block and lightening it wherever I could (by removing unused lugs and some of the strengthening webs) be:

A) foolish, compromising engine reliability and a complete waste of time
B) an interesting but most likely futile excerise
C) a possibility but only if you had lots of free time and a unhealthy obsession with car weight
D) so stupid I'm not even gonna bother replying

mookaloid - 22/12/13 at 06:51 PM

After due consideration I would say B)

CNHSS1 - 22/12/13 at 07:00 PM

On my nissan engines (also used in hilclimbers) i lop off any unused lugs, bosses etc from the inelt manifolds, gearboxes etc. My blocks are iron so rarely have cast bosses worth removing, they are usualy just tapped holes and bracket instead.
By removing the odds and sods i can usually lose 8-10kg, but just as helpful is the cleaner simplified engine bay. The protrusions removed are often the ones you have to sneak and hand/arm past to sort a loose item or leak trackside so much less liley to open ones skin and leak claret all over the place!

Like most lightening, its a bit pointless outside sprints/hills but as we have no weight minimums, it all adds up :-)

Pat_T - 22/12/13 at 07:16 PM

I design these sort of things for bike engines. I wouldn't go removing any strengthening webs whatsoever. We do FEA and all sorts and ribs on one side of the part may help to deal with thermal stresses in the combustion chamber for an example on a cylinder head, even if the Web is some distance from the area of concern.

However on head and block castings there are often a significant number of lugs that are there just for part datuming and clamping the part during machining.

you can lop these off no problem!

ReMan - 22/12/13 at 10:48 PM

Bits of A,B and C
Not stupid, will save a bit, but just avoid anything that is very obviosly redundant as it willlikely have a purpose

britishtrident - 23/12/13 at 10:18 AM

Absolute waste of time you might save a 2kg at most, it you want an easy way to save weight consider the driver weight.

Nosey - 23/12/13 at 10:49 AM

quote:
Originally posted by britishtrident
Absolute waste of time you might save a 2kg at most, it you want an easy way to save weight consider the driver weight.


I'm 6ft and barely over 11 stone, bar I start milling bits off myself I think I'm stuck with looking elsewhere!

Ah it was only a mad notion but I was curious as to the general consensus. It'll stay a long way down the to do list for a while yet, cheers for the opinions guys!

loggyboy - 23/12/13 at 11:10 AM

C

Along with all weight saving exercises - you have to add up all the small amounts. Anything that can be done for free (if you consider your time to be free) is never a futile exercise.

matt_gsxr - 23/12/13 at 12:20 PM

Don't forget to weigh it before and after.

iank - 23/12/13 at 12:46 PM

Might be worth starting with a lighter engine, it'll be cheaper in the long run.