New domain: www.Speed-Talk.com

The forum is currently running on the new domain and server. The old domain will remain active for a short while to forward any (less frequent) visitors.
IMPORTANT: Update your bookmarks to https://www.speed-talk.com/forum/

<6,000 RPM Street SBC Hone: Sunnen 818

General engine tech -- Drag Racing to Circle Track

Moderator: Team

ClassAct
HotPass
HotPass
Posts: 351
Joined: Wed Dec 05, 2018 11:55 pm

Re: <6,000 RPM Street SBC Hone: Sunnen 818

Post by ClassAct » Wed Dec 12, 2018 1:16 pm

NewbVetteGuy wrote:
Wed Dec 12, 2018 11:01 am
Thanks for all the replies!

I talked to the owner of the machine shop yesterday evening and he said that he doesn't know what Total Seal is talking about and this is just how he's been doing it for 30+ years and his race customers have no problems running 500 laps with this finish, so it should be good enough for a street motor....


I've confirmed that they definitely used a Sunnen 818 stone only it's even on my invoice.


For what it's worth, I'm looking to reuse my stock forged pistons with a 4.5 thousandths piston to wall clearance, and use a 1.2, 1.2, 3/16" ring set with spacers. Gapless steel top, napier 2nd, standard tension 20 lb oil ring.

-I'm mailing one piston to Total Seal to leave nothing to chance because as my forum name says I'm a complete Newb and I just don't trust myself to do anything fully right the first time.

Total seal recommended the cylinders be honed with 280 grit, medium pressure @ 50 strokes a minute with 3 full strokes.





Should I just buy a 240-280 grit aluminum oxide flex hone and go through each cylinder 3 times to try to get more depth on the cross-hatches to retain more oil, or am I better off leaving the cylinder wall finish as-is? It's a street car so longevity is kinda important...

(I'm honestly done with the machine shop; they've been nothing but trouble; they tried to give me someone else's heads back and tried to convince me they were mine, too... ??? The crank was polished beautifully, though.) -My options are:
1. Pay someone else to re-hone it
2. Run it as is
3. Flex hone it myself


Adam
Like I posted...if your tune up is good you'll be ok. Oil is what seals the rings. The finer the finish, the less oil retention you have. All the way down the bore, meaning even at the skirts. It won't take much to wash the oil off the bore if your not careful. I would also be careful on start up. Wipe the bores with ATF until the paper towel comes out clean. Then leave the bores alone. A very light coat of engine oil, assembly lube (depends on the lube...I don't use anything with moly paste in it on Pistons) or 2 stroke oil on the piston skirts is all you need. Don't slop a bunch of oil on the rings. That will help with initial ring seal.

Then keep the tuneup tight. You'll be fine. I wouldn't go back and undo what the shop already did.

NewbVetteGuy
Pro
Pro
Posts: 416
Joined: Sun Aug 07, 2016 4:11 pm

Re: <6,000 RPM Street SBC Hone: Sunnen 818

Post by NewbVetteGuy » Wed Dec 12, 2018 1:53 pm

ClassAct wrote:
Wed Dec 12, 2018 1:16 pm
NewbVetteGuy wrote:
Wed Dec 12, 2018 11:01 am
Thanks for all the replies!

I talked to the owner of the machine shop yesterday evening and he said that he doesn't know what Total Seal is talking about and this is just how he's been doing it for 30+ years and his race customers have no problems running 500 laps with this finish, so it should be good enough for a street motor....


I've confirmed that they definitely used a Sunnen 818 stone only it's even on my invoice.


For what it's worth, I'm looking to reuse my stock forged pistons with a 4.5 thousandths piston to wall clearance, and use a 1.2, 1.2, 3/16" ring set with spacers. Gapless steel top, napier 2nd, standard tension 20 lb oil ring.

-I'm mailing one piston to Total Seal to leave nothing to chance because as my forum name says I'm a complete Newb and I just don't trust myself to do anything fully right the first time.

Total seal recommended the cylinders be honed with 280 grit, medium pressure @ 50 strokes a minute with 3 full strokes.





Should I just buy a 240-280 grit aluminum oxide flex hone and go through each cylinder 3 times to try to get more depth on the cross-hatches to retain more oil, or am I better off leaving the cylinder wall finish as-is? It's a street car so longevity is kinda important...

(I'm honestly done with the machine shop; they've been nothing but trouble; they tried to give me someone else's heads back and tried to convince me they were mine, too... ??? The crank was polished beautifully, though.) -My options are:
1. Pay someone else to re-hone it
2. Run it as is
3. Flex hone it myself


Adam
Like I posted...if your tune up is good you'll be ok. Oil is what seals the rings. The finer the finish, the less oil retention you have. All the way down the bore, meaning even at the skirts. It won't take much to wash the oil off the bore if your not careful. I would also be careful on start up. Wipe the bores with ATF until the paper towel comes out clean. Then leave the bores alone. A very light coat of engine oil, assembly lube (depends on the lube...I don't use anything with moly paste in it on Pistons) or 2 stroke oil on the piston skirts is all you need. Don't slop a bunch of oil on the rings. That will help with initial ring seal.

Then keep the tuneup tight. You'll be fine. I wouldn't go back and undo what the shop already did.
Thanks for repeating that; I'm slow sometimes. I think it's finally sinking in.

When you say "if your tune up is good you'll be ok" and "be careful on start-up", you're talking about excess fuel washing down the cylinder walls being more of a problem with this fine of a finish (and therefore less oil retention on the cylinder walls, right?

-I'm using Holley HP EFI with port fuel injection and a knock sensor and I care about fuel economy so I'm planning on running it pretty lean and I can just make sure that the startup enrichment doesn't get too crazy.



Adam

ClassAct
HotPass
HotPass
Posts: 351
Joined: Wed Dec 05, 2018 11:55 pm

Re: <6,000 RPM Street SBC Hone: Sunnen 818

Post by ClassAct » Wed Dec 12, 2018 2:07 pm

NewbVetteGuy wrote:
Wed Dec 12, 2018 1:53 pm
ClassAct wrote:
Wed Dec 12, 2018 1:16 pm
NewbVetteGuy wrote:
Wed Dec 12, 2018 11:01 am
Thanks for all the replies!

I talked to the owner of the machine shop yesterday evening and he said that he doesn't know what Total Seal is talking about and this is just how he's been doing it for 30+ years and his race customers have no problems running 500 laps with this finish, so it should be good enough for a street motor....


I've confirmed that they definitely used a Sunnen 818 stone only it's even on my invoice.


For what it's worth, I'm looking to reuse my stock forged pistons with a 4.5 thousandths piston to wall clearance, and use a 1.2, 1.2, 3/16" ring set with spacers. Gapless steel top, napier 2nd, standard tension 20 lb oil ring.

-I'm mailing one piston to Total Seal to leave nothing to chance because as my forum name says I'm a complete Newb and I just don't trust myself to do anything fully right the first time.

Total seal recommended the cylinders be honed with 280 grit, medium pressure @ 50 strokes a minute with 3 full strokes.





Should I just buy a 240-280 grit aluminum oxide flex hone and go through each cylinder 3 times to try to get more depth on the cross-hatches to retain more oil, or am I better off leaving the cylinder wall finish as-is? It's a street car so longevity is kinda important...

(I'm honestly done with the machine shop; they've been nothing but trouble; they tried to give me someone else's heads back and tried to convince me they were mine, too... ??? The crank was polished beautifully, though.) -My options are:
1. Pay someone else to re-hone it
2. Run it as is
3. Flex hone it myself


Adam
Like I posted...if your tune up is good you'll be ok. Oil is what seals the rings. The finer the finish, the less oil retention you have. All the way down the bore, meaning even at the skirts. It won't take much to wash the oil off the bore if your not careful. I would also be careful on start up. Wipe the bores with ATF until the paper towel comes out clean. Then leave the bores alone. A very light coat of engine oil, assembly lube (depends on the lube...I don't use anything with moly paste in it on Pistons) or 2 stroke oil on the piston skirts is all you need. Don't slop a bunch of oil on the rings. That will help with initial ring seal.

Then keep the tuneup tight. You'll be fine. I wouldn't go back and undo what the shop already did.
Thanks for repeating that; I'm slow sometimes. I think it's finally sinking in.

When you say "if your tune up is good you'll be ok" and "be careful on start-up", you're talking about excess fuel washing down the cylinder walls being more of a problem with this fine of a finish (and therefore less oil retention on the cylinder walls, right?

-I'm using Holley HP EFI with port fuel injection and a knock sensor and I care about fuel economy so I'm planning on running it pretty lean and I can just make sure that the startup enrichment doesn't get too crazy.



Adam

Yes, fuel wash. Lie I said, the hone controls how much oil is on the cylinder wall. Except at the very top of the bore where the fuel will wash it away no matter what you do. That's why engine oils have additives to lube the top ring at the top of the bore.

If you run too much fuel through the engine, the finer hone retains less oil and it's easier to wash it away. And then you kill ring seal.

Also, most of the lower grade of so called 100% synthetic oils are not really synthetic. That's why guys can used also hold based fuels with the cheaper oils and still get the rings sealed. If you use a true 100% synthetic oil, you will have trouble keeping the rings sealed. That said, I see some guys claiming to run LAT oil on alcohol without issues.

I mention this because I see a lot of ring seal issues.

Also, I don't use moly top rings. That ring was developed so the factory could repair a cylinder without even honing it. There are much better rings out there. And oil is much better today.

Old School
Pro
Pro
Posts: 376
Joined: Sun Feb 13, 2005 11:27 am

Re: <6,000 RPM Street SBC Hone: Sunnen 818

Post by Old School » Wed Dec 12, 2018 2:12 pm

ClassAct wrote:
Wed Dec 12, 2018 2:07 pm
NewbVetteGuy wrote:
Wed Dec 12, 2018 1:53 pm
ClassAct wrote:
Wed Dec 12, 2018 1:16 pm


Like I posted...if your tune up is good you'll be ok. Oil is what seals the rings. The finer the finish, the less oil retention you have. All the way down the bore, meaning even at the skirts. It won't take much to wash the oil off the bore if your not careful. I would also be careful on start up. Wipe the bores with ATF until the paper towel comes out clean. Then leave the bores alone. A very light coat of engine oil, assembly lube (depends on the lube...I don't use anything with moly paste in it on Pistons) or 2 stroke oil on the piston skirts is all you need. Don't slop a bunch of oil on the rings. That will help with initial ring seal.

Then keep the tuneup tight. You'll be fine. I wouldn't go back and undo what the shop already did.
Thanks for repeating that; I'm slow sometimes. I think it's finally sinking in.

When you say "if your tune up is good you'll be ok" and "be careful on start-up", you're talking about excess fuel washing down the cylinder walls being more of a problem with this fine of a finish (and therefore less oil retention on the cylinder walls, right?

-I'm using Holley HP EFI with port fuel injection and a knock sensor and I care about fuel economy so I'm planning on running it pretty lean and I can just make sure that the startup enrichment doesn't get too crazy.



Adam

Yes, fuel wash. Lie I said, the hone controls how much oil is on the cylinder wall. Except at the very top of the bore where the fuel will wash it away no matter what you do. That's why engine oils have additives to lube the top ring at the top of the bore.

If you run too much fuel through the engine, the finer hone retains less oil and it's easier to wash it away. And then you kill ring seal.

Also, most of the lower grade of so called 100% synthetic oils are not really synthetic. That's why guys can used also hold based fuels with the cheaper oils and still get the rings sealed. If you use a true 100% synthetic oil, you will have trouble keeping the rings sealed. That said, I see some guys claiming to run LAT oil on alcohol without issues.

I mention this because I see a lot of ring seal issues.

Also, I don't use moly top rings. That ring was developed so the factory could repair a cylinder without even honing it. There are much better rings out there. And oil is much better today.
What rings do recommend that are not moly? Brand, part numbers, and cost for a 350 +.030. What is a tight tune up?

Newold1
Guru
Guru
Posts: 1962
Joined: Fri Apr 08, 2016 9:50 am

Re: <6,000 RPM Street SBC Hone: Sunnen 818

Post by Newold1 » Wed Dec 12, 2018 2:52 pm

Here is a great technical paper from Sunnen and information on honing and if you pay particular attention to pages 6 thru 13.
Pay particular attention on page 13 for a good description of why plateau honing is so valuable when done right. :wink:


www.sunnen.com/graphics/assets/document ... 5fbbbe.pdf
The Older I Get, The Dumber I Get :wink:

NewbVetteGuy
Pro
Pro
Posts: 416
Joined: Sun Aug 07, 2016 4:11 pm

Re: <6,000 RPM Street SBC Hone: Sunnen 818

Post by NewbVetteGuy » Wed Dec 12, 2018 7:05 pm

Newold1 wrote:
Wed Dec 12, 2018 2:52 pm
Here is a great technical paper from Sunnen and information on honing and if you pay particular attention to pages 6 thru 13.
Pay particular attention on page 13 for a good description of why plateau honing is so valuable when done right. :wink:


www.sunnen.com/graphics/assets/document ... 5fbbbe.pdf
Nice! Thanks for that.

Adam

Post Reply