Project D - 1 DEC 2007

Why do the engineers not grind rings? Maybe they have a valid reason? Like maybe the rings are specially treated on the outside to withstand heat, and you've just grinded off their protective coating? Make 100% sure otherwise you'll have another rebuild on your hands... :!:

Toby wrote:

Why do the engineers not grind rings? Maybe they have a valid reason? Like maybe the rings are specially treated on the outside to withstand heat, and you've just grinded off their protective coating? Make 100% sure otherwise you'll have another rebuild on your hands... :!:

hehehe you may be pushing it alittle this time toby

No no Tobles... Ring end gaps is the gap between the opening of the ring, remembered when we measured that gap with the feeler gauge... now that gap needs to be a specific minimum otherwize when the rings heats up the gaps will touch causing ring to scrape into the bore...

No I'm close to 100% sure I've done the correct thing, the reason why the engineers didn't grind the rings is that their calculations was wrong

See it works like this

Bore x 0.007" = Ring Gap

So

3.307" * 0.0065" = 0.021" Gap

What they did was they only took the 0.007" in account and measured that, never did the calculation, the gap before I grinded was 0.011", they only made sure the 0.007" feeler gauge went in there easily. The reason I know this is that they scribbled on that pamphlet 😕

Vlade wrote:

No no Tobles... Ring end caps is the cap between the opening of the ring, remembered when we measured that cap with the feeler gauge... now that cap needs to be a specific minimum otherwize when the rings heats up the caps will touch causing ring to scrape into the bore...

No I'm close to 100% sure I've done the correct thing, the reason why the engineers didn't grind the rings is that their calculations was wrong

See it works like this

Bore x 0.007" = Ring Cap

So

3.307" * 0.0065" = 0.021" Cap

What they did was they only took the 0.007" in account and measured that, never did the calculation, the cap before I grinded was 0.011", they only made sure the 0.007" feeler gauge went in there easily. The reason I know this is that they scribbled on that pamphlet 😕

Is your C mixed with your G?

Its GAP not CAP

naaah there was a problem between my keyboard and my chair... 😂 😂 Thanx

Vlade, I fully understand why you are doing the grinding (i.e. the gap size). My concern is that maybe the "ends" of the piston ring (as well as the rest of the ring) is specially treated (think of it like a coat of paint). By grinding the ends, you remove this coat, thus exposing the inner metal to the cylinder heat & chemicals. Maybe over time the metal corrodes or something? I'm just asking - I have no clue if this is the case or not.

Aaaah ok, 😀 Nah I think it should be fine since the pamphlet that comes with the pistons & rings say one have to check the gap size and gives one some pointers when grinding them... 😀 When you come around again I must show you...

That reminds me I actually need to borrow a 3/4" to 1/2" drive converter from you my Little MasterCraft socket set doesn't have one.

BTW Guys check this out, invaluable information when building engines http://forums.evans-tuning.com/viewtopic.php?t=326&highlight=gsr+engine+build

Toby no that is not the case, the rings need to be ground in order to get a complete seal, they dont cover the rings in anyway. You do get ceramic coated top rings but then they come pregapped and they dont need grinding.

Vlade my only objection to your handy tool it you are left with an ever so small gap because of the thickness of the grinding wheel. I prefer the ones where you grind one side then the other, that way you can get a perfect seal.

Toby,

Gapping rings isnt a "nice to have", its a must!

The thing is you will never get a perfect seal... Even a professional tool like Calibrator had didn't even make the grinded surface as smooth as my tool, mine is also a lot more square... The only reason why mine is smoother is because it runs at 10rpm where he used a hand tool... both equally effective.

Vlade wrote:

it runs at 10rpm

its gonna take a long time methinks

nah its was "quickish" faster than by hand, a ring took my about 10min of grinding measuring and what not...

It was a late night last night... :idea:

here some updates

Measured my bearing clearance with FlexiGuage you can get these at Alert Spares in PTA about R5.50

Next was the pistons, piston to wall clearance was also double checked... running at about 80 microns

In went the pistons

Then the squirter's

The rest followed rather quickly and I forgot to take pics

This is where I am now...

Now off to go do the head and rest...

Looks like it is coming alone nicely, so it should be running on Sunday then??

😉

You know you want to... just miss the event and keep working.

very very lekka,

i always knew about these plastigauges, but i've always wondered exactly what they looked like.

now i know! looks cool man!

Looking Good Man ... :200sx_200sx:

Mega MG gasket set...

I have about 3 half kits in the garage, Also was the blocked decked and the head skimmed ?

Phinx wrote:

I have about 3 half kits in the garage, Also was the blocked decked and the head skimmed ?

😀 Thanks, yip block was decked and head was skimmed, I think this is the 4th skim this head has had... I did ask them to remove as little material as possibly needed...

Good News is engine is in, and I've done about 10Km now, but my Wolf 3D is giving me hassles, having a real hard time starting the car, it keeps on flooding or something, It started briefly this morning, wanted to go for a drive but it died in my driveway after that it wanted nothing.

Will post pics tomorrow.

sweet dude!

cant wait to see you drifting that beast!