Go Back   Corvette Forum > C3 Corvettes, 1968 - 1982 > C3 Tech/Performance
Sign in using an external account
Register Forgot Password?
Register Search Today's Posts Mark Forums Read FAQ Vendor Directory
Search
C3 Tech/Performance
V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette Sponsored by
VBP

Welcome to Corvetteforum.com!
Welcome to Corvetteforum.com.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join Corvetteforum.com today!


Corvette Store
 
 
C7 Parts & Accessories
C6 Parts & Accessories
C5 Parts & Accessories
C4 Parts & Accessories
C3 Parts & Accessories
C2 Parts & Accessories
C1 Parts & Accessories
Wheels & Tires
Sponsored Ads
 
 
Vendor Directory
  
Reply
 
 
 
 
Thread Tools Search this Thread
Old 12-07-2009, 03:31 PM   #1
Matt Gruber
CF Senior Member
 
Member Since: Oct 2000
Location: New Smyrna Beach, FL
Default Low tension rings- How much HP & MPG are they worth?

Years ago I read about the many improvements in the LS1, on how the ring tension was lower than other car makers would dare try. This gave a significant power advantage and better mpg.
Anyone try them;dyno them;see a dyno comparison? or any mpg info?
Matt Gruber is offline   Reply With Quote
Old 12-07-2009, 04:01 PM   #2
gerry72
CF Senior Member
 
Member Since: Aug 2000
Location: San Antonio TX
Default

Most drag (friction) comes from the rings. Anything you can do to reduce drag will improve efficiency. Thinner rings in stainless with less radial thickness are the trend in the OEM so I'm sure they have the data to back it up. I'm not talking about gas port or rings intended for a race application. Those are very different and should not be used on a normal street engine.
gerry72 is offline   Reply With Quote
Old 12-07-2009, 11:40 PM   #3
Buddy1980
CF Senior Member
 
Member Since: Nov 2008
Default Low tension rings

My 2001 C-5 convertible came with low tension rings from the factory. Although I do not drive the car a lot, (16,000 miles since 2002), I found it would use a little oil between oil changes which were usually about 2000-2500 miles apart. I would change the oil once a year to keep the warranty valid, and my engine was using about 1 quart between changes. I then learned that Chevrolet had a service bulletin on the oil consumption, and they would change the rings if I complained. Although it kinda pissed me off at first when I learned the reason of the oil consumption, I decided that instead of the dealer replacing rings in my new car, I would just add a little oil now and then. I will say that the engine runs fantastic and maybe it is a little faster because of the low tension rings. I found out that in 2002 the Corvette engines had different rings installed at the factory, maybe because of the oil issue in the past. By the way, I never see any exhaust smoke, only a little black on the chrome exhaust tips. Since the car runs so strong, I have just decided not to worry about it and just add a little oil every now and then.
Buddy1980 is offline   Reply With Quote
Old 12-09-2009, 06:25 AM   #4
jackson
CF Senior Member
 
Member Since: Sep 2001
Location: Timmonsville SC
Default

afaik, in last 10-15 yrs, every/all motor regardless of make has OE thin lower tension ringpak.

iron head vortecs 4.3L v6 & 5.0/5.7L v8 have lower tension ringpak, narrow too 1.5mm,1.5mm,3mm. zillions in vans & trucks. They work great over about 13-year history. And, those I've pulled apart show markedly little bore wear.

Lower tension rings can work because of better bore machining/honing techniques that yield straighter bores, w/ tighter tolerances & better control of hone-pattern/finish. Simply slapping a thin aka lite ringpak in a bore that's prepped the old way won't last long.
jackson is offline   Reply With Quote
Old 12-09-2009, 10:15 AM   #5
Matt Gruber
CF Senior Member
 
Member Since: Oct 2000
Location: New Smyrna Beach, FL
Default

jackson
thanks for your reply.
is a sunnen CK-10 w/honing plate sufficient?
any comments on bore finish? fine? mirror?
Matt Gruber is offline   Reply With Quote
Old 12-09-2009, 10:18 AM   #6
fauxrs
CF Senior Member
 
fauxrs's Avatar
 
Member Since: Nov 1999
Location: San Diego CA
Default

When I built my new engine I set it up with 1.5mm,1.5mm,3mm low tension thin ringpak. That was 5 years ago with no issues. I wish I could give you HP numbers though as I dont have them.
__________________
1978 L-82, Tremec TKO 5 speed, Sunset Red mettalic, offset trailing arms,
New engine by me
tuned by Lars
My Corvette Web Site



'Idiocracy' was a warning, not a comedy.
fauxrs is offline   Reply With Quote
Old 12-09-2009, 10:26 AM   #7
...Roger...
CF Senior Member
 
...Roger...'s Avatar
 
Member Since: May 2006
Location: Dayton, Ohio
Default

Quote:
Originally Posted by Buddy1980 View Post
By the way, I never see any exhaust smoke, only a little black on the chrome exhaust tips.
If your using synthetic oil I understand it won't show smoke out the exhaust so if thats true that could be the reason.
...Roger... is offline   Reply With Quote
Old 12-09-2009, 12:56 PM   #8
jackson
CF Senior Member
 
Member Since: Sep 2001
Location: Timmonsville SC
Default

Quote:
Originally Posted by Matt Gruber View Post
jackson
thanks for your reply.
is a sunnen CK-10 w/honing plate sufficient?
any comments on bore finish? fine? mirror?
Hone plate required. CK10 aok ... but any tool must be well-maintained. The finish depends on what type stone is used ... not simply grit but what stone's made from. What ring is made of/faced with has everything to do with desired finish. Follow ring manufacturers' MOST RECENT recommendations. It's not rocket science but there's MUCH more to it than a plate & finish. One thing I've seen that seems helpful is ... after honing ... say the stone hone WAS turning clockwise ... go in afterward with a flexbrush hone and turn it counterclockwise a few strokes ... in reverse of what stone had turned. This helps knock off the high spots & helps create a desired plateau finish. Too shiney is bad; won't hold enough oil.

also, take a look at articles such as these three:
http://www.enginebuildermag.com/Arti..._finishes.aspx

and:
http://www.enginebuildermag.com/Arti...d_sealing.aspx

and:
http://www.enginebuildermag.com/Arti...rformance.aspx

from a whole host of ring articles here:
http://www.enginebuildermag.com/Sear...rm=piston+ring

lotsa good, reliable pro tech info in engine builder mag ... but you probably won't find it at a newstand ... it's a pro trade mag; your local machine shop probably has a free subscription. If ya really wanna know about rings finish etc ... there's plenty at ebm to keep you busy ... & pretty good concensus too ... unlike too many threads here.

fyi ... thin ring can mean two things ... how wide the ring groove (Y) is & how deep it is (X) ... ring depth on ring referred to as "radial thickness" ... that's become thinner also.

more hp & mpg ... yes ... how much, I dunno ... but nowadays they've all got thin OE ringpaks ... less friction.
jackson is offline   Reply With Quote
Old 12-09-2009, 02:27 PM   #9
Little Mouse
CF Senior Member
 
Member Since: Apr 2006
Default

They claim 70 percent of friction in an engine is caused by the rings
using at least thinner rings makes good sense.
mahl piston and ring sets come with 1.5 thin rings for a good price.

Think how much easier it is for the oil pump to pump thin syn oil.
Little Mouse is offline   Reply With Quote
Old 12-10-2009, 10:24 AM   #10
Matt Gruber
CF Senior Member
 
Member Since: Oct 2000
Location: New Smyrna Beach, FL
Default

Quote:
Originally Posted by jackson View Post
Hone plate required. CK10 aok ... but any tool must be well-maintained. The finish depends on what type stone is used ... not simply grit but what stone's made from. What ring is made of/faced with has everything to do with desired finish. Follow ring manufacturers' MOST RECENT recommendations. It's not rocket science but there's MUCH more to it than a plate & finish. One thing I've seen that seems helpful is ... after honing ... say the stone hone WAS turning clockwise ... go in afterward with a flexbrush hone and turn it counterclockwise a few strokes ... in reverse of what stone had turned. This helps knock off the high spots & helps create a desired plateau finish. Too shiney is bad; won't hold enough oil.

also, take a look at articles such as these three:
http://www.enginebuildermag.com/Arti..._finishes.aspx

and:
http://www.enginebuildermag.com/Arti...d_sealing.aspx

and:
http://www.enginebuildermag.com/Arti...rformance.aspx

from a whole host of ring articles here:
http://www.enginebuildermag.com/Sear...rm=piston+ring

lotsa good, reliable pro tech info in engine builder mag ... but you probably won't find it at a newstand ... it's a pro trade mag; your local machine shop probably has a free subscription. If ya really wanna know about rings finish etc ... there's plenty at ebm to keep you busy ... & pretty good concensus too ... unlike too many threads here.

fyi ... thin ring can mean two things ... how wide the ring groove (Y) is & how deep it is (X) ... ring depth on ring referred to as "radial thickness" ... that's become thinner also.

more hp & mpg ... yes ... how much, I dunno ... but nowadays they've all got thin OE ringpaks ... less friction.
i read the 1st 3. i see there is plenty room for improvement on my rebuilt in '94, '74 355. It is an old school set-up, forged LT-1 pistons w/ 5/64 rings, medium tension. It has SpeedPro R-9343-035 rings, .012" gap on top. I went too far on 3 of the 2nd rings, to .015", that turns out to be better than the .012 on the rest
I liked the 4cyl 0.8 top ring - 62 mpg i guess with a v8 i'd be lucky to get 31 mpg
I get 18-19 mpg now w/4.11, so i'm not complaining.
Thanks for all the links! Great reading for any gearhead!
Matt Gruber is offline   Reply With Quote
Old 12-10-2009, 11:04 AM   #11
jackson
CF Senior Member
 
Member Since: Sep 2001
Location: Timmonsville SC
Default

Quote:
Originally Posted by Matt Gruber View Post
.... I went too far on 3 of the 2nd rings, to .015", that turns out to be better than the .012 on the rest....
yep, 2'nd gap wider than top gap is SOP today
Quote:
Originally Posted by Matt Gruber View Post
....I get 18-19 mpg now w/4.11, so i'm not complaining....
right, seems you got great results no matter how you got there.
jackson is offline   Reply With Quote
Old 12-11-2009, 12:17 AM   #12
Matt Gruber
CF Senior Member
 
Member Since: Oct 2000
Location: New Smyrna Beach, FL
Default

Quote:
Originally Posted by Little Mouse View Post
They claim 70 percent of friction in an engine is caused by the rings
using at least thinner rings makes good sense.
mahl piston and ring sets come with 1.5 thin rings for a good price.

Think how much easier it is for the oil pump to pump thin syn oil.
Thanks for that piston info!
My 61 engine only has 7k on it, bored 030 on a CK-10 honed to a fine finish w/hone plate. Do u guys think a hand hone would be good enough to try a low friction ring set up? Using some oil is not a problem, i only go 500mi/yr.
If i could get mpg into the 20's i maybe could make some wager money, and pay for the pistons
some guys here think efi is needed for good mpg. i think is is more from efficiency.
Thanks guys for giving me a new project to think about!
Matt Gruber is offline   Reply With Quote
Old 12-11-2009, 03:21 AM   #13
jackson
CF Senior Member
 
Member Since: Sep 2001
Location: Timmonsville SC
Default

Quote:
Originally Posted by Matt Gruber View Post
Thanks for that piston info!
My 61 engine only has 7k on it, bored 030 on a CK-10 honed to a fine finish w/hone plate. Do u guys think a hand hone would be good enough to try a low friction ring set up? Using some oil is not a problem, i only go 500mi/yr.
If i could get mpg into the 20's i maybe could make some wager money, and pay for the pistons
some guys here think efi is needed for good mpg. i think is is more from efficiency.
Thanks guys for giving me a new project to think about!
In your conditions-usage only ... 500 mi/yr & oil-drinker ok ... I say go ahead & try it ... but otherwise, No.

Before it's honed but with hone plate torqued to that block, I'd be interested to see bore taper data. It may or may not remain straight.
jackson is offline   Reply With Quote
Old 12-11-2009, 02:58 PM   #14
TheSkunkWorks
CF Senior Member
 
TheSkunkWorks's Avatar
 
Member Since: Apr 2007
Location: Graceland in a Not Correctly Restored Stingray
Default

FWIW, my hi-po street 427 BB makeover is getting standard tension 1/16" top and second rings (moly/iron), and will be honed (should clean up at .005" over) with proper plates and studs. As I'm not trying to squeeze every last ounce of power out of it and don't plan on tearing back into it for at least 20,000 miles (and plan to put more that a handful of miles on it each year), I'm not willing to experiment with thinner and/or lower tension rings. On the other hand, if I were building it up strictly for track days that might well be a different story.


TSW
TheSkunkWorks is offline   Reply With Quote
Old 12-13-2009, 03:24 PM   #15
Matt Gruber
CF Senior Member
 
Member Since: Oct 2000
Location: New Smyrna Beach, FL
Default

Quote:
Originally Posted by jackson View Post
In your conditions-usage only ... 500 mi/yr & oil-drinker ok ... I say go ahead & try it ... but otherwise, No.

Before it's honed but with hone plate torqued to that block, I'd be interested to see bore taper data. It may or may not remain straight.
I am looking for a way to compare engine friction.
I checked with a tq wrench on front of the crank, takes 60# to slowly move 1/4" cold, same hot.
I plan to look for some circle track "claimer" pistons. I want to bump up from 9.7 to 10.2-10.9 and use hi-test instead of 87. And use low tension rings, as thin as available. I see it has blow by at 200F, so i see it really should be hot-honed
Matt Gruber is offline   Reply With Quote
Old 12-13-2009, 03:24 PM
 
Go Back   Corvette Forum > C3 Corvettes, 1968 - 1982 > C3 Tech/Performance
Reload this Page Low tension rings- How much HP & MPG are they worth?
 
 
 
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
How accurate is your average MPG? Kale C5 General 28 01-14-2013 08:45 AM
Mpg Kid96 C4 Tech/Performance 32 11-13-2012 05:27 PM
Whats Your City MPG?? GGEENN C5 General 27 10-15-2011 09:56 PM
89 C4 dash cluster problems jzvette C4 Tech/Performance 25 05-31-2011 12:11 PM
What is the algoritm to calculate MPG? mundo C6 Corvette General Discussion 22 02-11-2011 02:29 PM


Tags
forum, gain, horsepower, hp, low, mpg, oil, ring, rings, smoke, std, tension, tention


Thread Tools Search this Thread
Search this Thread:

Click for Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump


All times are GMT -4. The time now is 12:25 PM.


Emails & Password Backup