during a rebuild what piston rings?

[Turbo Archie]

Actually I have not verified if its 30 over, I will verify that upon disassembly this sunday.

Another thing to consider that is often over looked, will you have the correct piston to wall clearance after you hone?
If it has high mileage and a lot of wear, it might take a thou or more to clean up and that might put you out of spec....

 

[outatime86]

Another thing to consider that is often over looked, will you have the correct piston to wall clearance after you hone?
If it has high mileage and a lot of wear, it might take a thou or more to clean up and that might put you out of spec....

Great advice! Motor was a daily driver for 2 years then sat in my driveway for 20 years. I'll find out this Sunday when I pull it n disassemble.

 

[TIMINATOR]

A straight, round bore with a proper hone by an experienced RACE shop is more important than shooting for the perfect piston/bore clearance, AS LONG AS YOU HAVE ENOUGH CLEARANCE FOR THE PISTONS ALLOY, and BOOST LEVEL!
I would rather see a perfectly honed, straight bore (within a total of .0003" varience) with an extra thou or two clearance, rather than a perfect size somewhere, and taper, either large or small, elsewhere, and a sub par finish. Keep in mind, we have seen a LOT of engines come thru here that have required .030" overbore to clean up that were in old bracket race, and street cars that ran in the TENS at over 130 mph! Out here in the AZ. area, we see 80-90 plus MPH jet and prop boats that run great but needed a .030 overbore too. Out here, if your boat won't break 90 or 100 mph, nobody gives it a second look.
For what you are doing, you don't need to fixate on a torque plate hone, just a proper wall finish, minimum required clearance, done on a quality machine, by someone who has been building nothing but performance engines for years. Not a general rebuilder that does an occasional 383 with a street cam!
Torque plates are needed more on 400 small block and 4.500" plus bore big block Chevies because their head bolts are extremely close to the cylinder bores, are not countersunk, and thread directly into the deck.
Our little Buicks have deeply recessed head bolt bosses and the threads are a lot farther away from the cylinder bores, in addition to the blocks and heads being cast from a much stronger, harder iron alloy containing nickle and tin.
Also, when torque plate honing, you must use a new gasket of the same brand, type, and thickness, FOR EACH BANK, and the same fasteners, of the same type, and torque you will be assembling the engine with. Anything less, and you are pissing in the wind!
We old guys that have been experimenting with torque plates, and honing techniques since the 1970s, can pretty much look at the design of an engine, and material they are cast from and know whether a torque plate is needed or just a "feel good" waste of cash FOR THE APPLICATION.
The measure (pun intended) of what blocks need to be torque plate honed is simple, hone one bank with it, measure the concentricity of the bore, then remove the torque plate and re measure. The aforementioned Chebbies will generally have as much, or more than one and a half thousandths change at the bolt holes, SBFords have less because of countersunk headbolt holes, LS chebbies, Honda B16 and 18s, and V- 6 Buicks have very deeply recessed headbolt bosses, and 455 Olds are even better, as the bolt bosses are cast into the water jacket, not the cylinders, and are much farther away from the cylinders. These characteristics will change the bore distortion from bolting on the heads.
Look at your block, check out your machineshop and see how much percentage of engines in there are stock, or hi perf. Then ask if they are using new gaskets of the same ones you are installing, whether they are using your gaskets, fasteners and fastener lube, how many different grit stones they will use, what is their bore tolerance in ten thousandths, and then decide which shop you are using, and whether you really need torque plate honing in your application. A properly designed torque plate will use the same length bolts or studs in the same locations as the head requires.
TIMINATOR

 

[outatime86]

A straight, round bore with a proper hone by an experienced RACE shop is more important than shooting for the perfect piston/bore clearance, AS LONG AS YOU HAVE ENOUGH CLEARANCE FOR THE PISTONS ALLOY, and BOOST LEVEL!
I would rather see a perfectly honed, straight bore (within a total of .0003" varience) with an extra thou or two clearance, rather than a perfect size somewhere, and taper, either large or small, elsewhere, and a sub par finish. Keep in mind, we have seen a LOT of engines come thru here that have required .030" overbore to clean up that were in old bracket race, and street cars that ran in the TENS at over 130 mph! Out here in the AZ. area, we see 80-90 plus MPH jet and prop boats that run great but needed a .030 overbore too. Out here, if your boat won't break 90 or 100 mph, nobody gives it a second look.
For what you are doing, you don't need to fixate on a torque plate hone, just a proper wall finish, minimum required clearance, done on a quality machine, by someone who has been building nothing but performance engines for years. Not a general rebuilder that does an occasional 383 with a street cam!
Torque plates are needed more on 400 small block and 4.500" plus bore big block Chevies because their head bolts are extremely close to the cylinder bores, are not countersunk, and thread directly into the deck.
Our little Buicks have deeply recessed head bolt bosses and the threads are a lot farther away from the cylinder bores, in addition to the blocks and heads being cast from a much stronger, harder iron alloy containing nickle and tin.
Also, when torque plate honing, you must use a new gasket of the same brand, type, and thickness, FOR EACH BANK, and the same fasteners, of the same type, and torque you will be assembling the engine with. Anything less, and you are pissing in the wind!
We old guys that have been experimenting with torque plates, and honing techniques since the 1970s, can pretty much look at the design of an engine, and material they are cast from and know whether a torque plate is needed or just a "feel good" waste of cash FOR THE APPLICATION.
The measure (pun intended) of what blocks need to be torque plate honed is simple, hone one bank with it, measure the concentricity of the bore, then remove the torque plate and re measure. The aforementioned Chebbies will generally have as much, or more than one and a half thousandths change at the bolt holes, SBFords have less because of countersunk headbolt holes, LS chebbies, Honda B16 and 18s, and V- 6 Buicks have very deeply recessed headbolt bosses, and 455 Olds are even better, as the bolt bosses are cast into the water jacket, not the cylinders, and are much farther away from the cylinders. These characteristics will change the bore distortion from bolting on the heads.
Look at your block, check out your machineshop and see how much percentage of engines in there are stock, or hi perf. Then ask if they are using new gaskets of the same ones you are installing, whether they are using your gaskets, fasteners and fastener lube, how many different grit stones they will use, what is their bore tolerance in ten thousandths, and then decide which shop you are using, and whether you really need torque plate honing in your application. A properly designed torque plate will use the same length bolts or studs in the same locations as the head requires.
TIMINATOR

Copy that 10-4! I would love to see a .0003" variance in the cylinders after hone. On Sunday the motor comes out and I'll post up pics of the cylinder walls, some people have contacted me and mentioned the same thing regarding the torque plate you have in that its not really needed unless your going balls out on a race motor, due the design of the head bolts n block vs a sbc or ford. The machine shop I'm looking at using is L & R Engines they are local here in SoCal and have about a two week lead time at the moment. Larkin the owner and grandson Derek were recommended to me by someone on the board who has been using them for decades for GN motor machining. After disassembly I'll speak with Larkin in depth and send him pictures of the cylinder walls to see what he recommends as well. Crossing fingers that maybe there are some good signs of cross hatching still maybe I won't need to torque plate hone at all, and the machinist can just concentrate on honing smooth to tight variances. If I go the torque plate route I would give the machine shop my new head gaskets and also my arp head bolts to use in the process. When I speak to Larkin I will make a note to ask him how many different grit stones they use in the process of honing, as well as their tolerances in the 10 thousandths.

Timinator, what a great post!!! Thank you for sharing in depth. The board has been great to me and all of my questions, as a first time rebuilding I'm learning more then I could have imagined.

 

[TIMINATOR]

We do a FIVE step hone, finishing up with Sunnen Ultra finish inserts.
Rings are the major cause of friction in modern engines, but with proper wall prep, narrow and low drag rings will reduce that.
Every .001" of taper causes the ring gap to change by .00314". That taper causes friction between the ring and piston reducing the ability of the rings to stay in contact with the bore for compression, cylinder combustion pressure, heat dissapation, and oil control.
Also, blower/turbo rings have a higher wall pressure for better sealing and heat dissipation to the cylinder, but that will cause more rapid cylinder wear, and drop fuel efficiency, if anyone here cares. Bottom line, don't use killer blower rings if you don't need them, it will make it more difficult to pass smog check, wear out the cylinders quicker, and reduce fuel mileage.
Note: my posts are NOT for advertisement purposes, I am semi retired, and I don't need the work, the posts are for information and occasionally, entertainment purposes only.
TIMINATOR

 

[outatime86]

We do a FIVE step hone, finishing up with Sunnen Ultra finish inserts.
Rings are the major cause of friction in modern engines, but with proper wall prep, narrow and low drag rings will reduce that.
Every .001" of taper causes the ring gap to change by .00314". That taper causes friction between the ring and piston reducing the ability of the rings to stay in contact with the bore for compression, cylinder combustion pressure, heat dissapation, and oil control.
Also, blower/turbo rings have a higher wall pressure for better sealing and heat dissipation to the cylinder, but that will cause more rapid cylinder wear, and drop fuel efficiency, if anyone here cares. Bottom line, don't use killer blower rings if you don't need them, it will make it more difficult to pass smog check, wear out the cylinders quicker, and reduce fuel mileage.
Note: my posts are NOT for advertisement purposes, I am semi retired, and I don't need the work, the posts are for information and occasionally, entertainment purposes only.
TIMINATOR

School is in session! Ty Tim, I'm excited to see what the machine shop says is their process.

L & R Engines

 

[TIMINATOR]

For all of you folks rebuilding yer engines, most custom piston mfgrs. will make any size pistons, they don't have to be a specific standard oversize, and Total Seal will make you ANY size ring you desire to go with them. We have done LOTS of in between bore, oversized engines. Especially our Buicks, 4.600 bore Merlins, and 400 sbc engines.
On my 4.600 bore, 14-71 blown, intercooled, fogger N2O, boat engine, originally built at the "maximum recomended bore size" of 4.600", I hurt it and honed the worst cylinder to 4.608", then the next time, I made it 4.615". It's still running 12 years later! Cometic makes all kinds of sized custom headgaskets too.
Just did a 383 Chebbie refresh at .045" over last month.
"If the box is too limited, think outside of it!"
TIMINATOR

 

[TIMINATOR]

Two quick additional thoughts:
Read the ENTIRE thread entitled: "has anyone ever seen this with Cometic gaskets?"
Not just my posts, but all of it contains a lot of info that most folks, and many machineshops are not aware of.
Great pic of a beautiful torque plate, but it is not made of the same material as your heads. Iron plate for iron heads, aluminum plate for aluminum heads.
It must also use the stock factory bolts, or aftermarket studs, in the same location and length as will be installed in whatever your build will be using. Don't forget to use, only once, new headgaskets of exactly the same type, brand, and thickness that will be used in the final build.
Read the info section of the ARP catalogue!
ARP makes reduced shank studs for many applications to address the clamp load disparity of different length fasteners. Over torquing of intake manifold fasteners also affects headgasket clamp loads.
Now all of you that swear by torque plate honing need to examine if your machineshop actually knows how to do the hone job correctly. Or if your torque plate hone is a waste of time and money.
If it is not done correctly, why bother at all? Bore distortion can easily be made worse by doing it incorrectly!
More things that make you wonder how you are going as fast as you are, or aren't.
TIMINATOR, Again raining on parades and pissing on your Cheerios....

 

[TIMINATOR]

It is easy to see if your torque plate hone was done correctly. Bolt the head on your bare block with a new headgasket and the fasteners you are going to use. Set up the tenths indicating dial bore gauge, and read it all around the bore from the crankcase up as close to the deck as possible.
We learned the best way to hone by doing the drivers side bank our traditional way, and the passenger side with our every new idea.
We checked the leakdown and notated it for both sides, then after every race we leaked it down again.
That's how we came about doing things the way we do.
If you really want to win, hone the block with 180 degree water circulating in it.
In my world, anal is short for analyze.
Not an insult, but a badge of honor!
TIMINATOR
P.S. my new build uses Total Seal Classic CS 5899 +.005 (file fit + .020)

 

[Mr.Spool]

Now all of you that swear by torque plate honing need to examine if your machineshop actually knows how to do the hone job correctly. Or if your torque plate hone is a waste of time and money.
If it is not done correctly, why bother at all?

Amen

 

[underpressure1]

I'm in the process of rebuilding my motor due to blown head gasket. What brand or model of piston rings do you use? Motor is a stock 109 block 30 over girdled, forged pistons/rods/crank with aluminum heads, new alky injection, t66, FAST ecm, supporting bolt on's. I've read great things about total seal gapless 2nd rings and I enjoy their website's tech articles. Includes great information regarding cylinder walls and oil, also fuels such as methanol and blow by, interesting stuff! But it looks like their piston rings are around $300-$400 a set not cheap, was wondering what else is out there or are these normal prices for rings these days? Not trying to break any records, want to run 25-30psi. Haven't talked to my machine shop yet regarding piston rings fyi. First I wanted to see what your experience has been or what you would do differently.

Thanks for your time and input!

Use Molly rings and ring them on the loose side

 

[TIMINATOR]

Moly is fine under 10-15 lbs. I prefer plasma moly on a harder ring above that.
To each, his own thing...
But then again, I'm anal...
TIMINATOR

 

[Chuck Leeper]

@35psi we saw some moly coming off the rings.
But we ran higher egt's than some folks would like to see.

 

[TIMINATOR]

Sorry all, about my long posts, but I'm the guy that you would ask what time it is, and I'll tell you how to build a clock.....
TIMINATOR

 

[outatime86]

You get the idea. All the pistons n cylinder walls look this bad. The real PITA is that the block is already 40 over. Looking for a new used block atm.

Also found out it had a cast crank in it. So I bought a forged crank. Waiting to know for sure what block I'm getting before buying rods n pistons. I forgot to post up here but I did in the SW section.

Both the drivers and passenger side head gaskets blew btw.

 

[outatime86]

I'm letting the torque plate idea go away in favor of a great honing job. I also like the idea of Total Seal Classic CS rings they arebt too expensive but also not cheap by any means.

 

[TIMINATOR]

Take your block to a EXCELLENT machineshop, have them dial bore guage the cylinders. It may clean up at .o45 or so. Custom pistons are cheaper than another block! Total Seal will make u any size rings but you won't need them, because file fit rings are .005 over

 

[TIMINATOR]

and you have to run a bigger end gap anyway with a turbo. See if it cleans up at .045 or .050, if so, buy custom pistons and file fit performance rings.
If the thickness of less than a sheet of paper on the cylinder walls is an issue, you have other problems. Spend the block cash on good machining, and ARP everything.
All Turbo Buicks had cast steel cranks with rolled fillers. Ask Mr. Spool how fast he has run on a stock bottom end.
TIMINATOR

 

[SCOOBY DOO]

Stock bottom end will run bottom 10's with zero KR. Eventually the stock piston will crack across the line of the wrist pin.

 

[TIMINATOR]

And the stock piston pins weigh about 225 grams! That's a HALF A POUND!!!! EACH!
Normal pins run about 135 to 150 grams, tool steel, about 95 or so. That's reciprocating weight too, ya have to start it moving at the top stop it at the bottom, start it at the bottom, and stop it at the top, EVERY revolution! AND, every bit of weight you take off of the piston, pin, rings,and small end of the rod, you will also take off of the counterweight during the balancing process too, and you need to do that anyway.
Lighter weight parts allow the engine to make more power, rpm faster, and reduce the load on the rods, and rod and main bearings too.
Lighter weight doesn't need to be your main criteria, but it helps narrow down your choices in any performance build.
Aftermarket pistons also use Lighter, and narrower rings, and have more ring choices too.
TIMINATOR