rwilles
Registered User
Sorry for the delay in all this but Family Court and head gaskets in a 2.3 Audi and a 4.0 Jeep took "urgent but not important" time over the last 3 months.
Skip down to "New Gasket Design" if you want just the new gasket stuff.
I want my truck to run for another 18 years before another major overhaul (I know wishful thinking!) so I want to get this gasket/stud/timing thing right. My conclusions about the weakness of the head gaskets in our engines has lead to a lot of reading both about the gaskets and the explosion that they are trying to contain. There is a great article at Oliver Diesel about the effect timing has on power transfer and emissions, http://www.oliverdiesel.com/tech/timing.htm.
Net result is that the more the engine timing is advanced the greater the amount of a cylinder pressure charge is transferred to the only thing that will move in that millisecond, the gasket. Add to timing setting the fact that our fuel injection system is mechanical, and so a weak injector means extra advance in that cylinder that is also fuel starved, a lean burn situation. In airplanes too lean a mixture will 'melt' pistons, and blow gaskets. Hypermax adds this warning on their performance carbon fiber head gaskets "Stacking of boxes will also fail the gasket. This means using an in-line programmer along with programming the factory PCM. This is due to the extreme timing advance that is produced by both modifications."
I think I created this situation on my truck when I had two injectors 'replaced' (no rebuild markings on them, so used?) at a shop shortly after I bought the truck and knew nothing about a idi diesel, add to that, I advancing the timing 2-3 dimes thickness, add to that towing a 15,000lb load of wood from Montrose to Colorado Springs (3 passes) and I get a gasket failure between the middle pistons on the passenger side at the last pass. Normal EGT were under 900 deg. I may have touched 1050 at the top of the passes but the gauge only shows an average of 8 cylinders. If I could have measured that one cylinder I believe it would have shown significantly higher.
Lesson#1: If I am running an advance on the timing pump I will always have my injectors pop tested to match each other. Then the timing for all the cylinders is the same! DPS shows $32 per injector x8= $256.
Head Studs or Bolts? The torque ratings on the 6.9 and 7.3 are different because of 7/16" (85-90lbs) vs 1/2" (105-115 lbs) studs. There were 180,000lb, 200,000lb and 220,000lb rated alloys made. The 220,000lb option was a failure as the studs would snap after a few heat cycles, from DPS's experience. Both bolts and studs are available in the lower rated alloys, online, but I wont trust steel from India in my truck. Some have said there is as much as 3 times the clamping force with the nut on a stud because there is less threads (1/2 an inch vs 1 1/2 inch) being twisted. Follow the 5-7 time tightening process outlined by head gasket manufactures and ARP to remove any gauling from the threads. Victor-Reinz says on their commercial site that bolts have a 30% error rate while the studs have only a 10%. ARP studs are available from TYPE4, last he posted around $400.
Biggest gain seems to come in the re-tightening of the nuts after the engine has been heated and cooled. On a side note I got almost a 1/8 extra turn on the 4.0 Jeep after running it once, didn't bother with the Audi as you have to take everything down including the intake manifold.
Gaskets Composite - Gaskets Carbon Fiber - Shims
Composite- Felpro Gasket. AutoZone $34 x 2, 1 year warranty. .035" thick. compressed ? Best description I have heard is a bunch of micro rubber like balls mixed up in a batch of asphalt like stuff and shaped into a gasket. If you could see one of those pressure maps that they have for all the foam beds there would be a pattern of hi-pressure dots and low pressure voids that cover the gasket. This is moderated by the rubber like coating that they put on the surface of the gasket. As engine pressure increases it is forced in between the micro-balls and erodes the goopy stuff. (high-tec description is free of charge) As the only difference I can see on the 7.3 turbo and non-turbo motors is the thickness of the head gasket, I think this gasket will raise the compression ratio back to the stock 23:1 compression ratio. Add more turbo and gasket problems will follow.
Carbon Fiber (new)- Victor-Reinz. Auto Zone $50 x , 2 year warranty. .05" thick out of the box. V-R says will compress 10% to .045". In concept the carbon fiber is like a very thick forest standing straight up. There is a perforated metal center plate that has two layers of carbon fiber. The fibers are different lengths and interlock as compressed. Each layer custom fits to the surface it mounts on. If you go back to the pressure map idea it will all shows the same pressure or color. No high spots or low voids. This doesn't compress as much as the old material and does conform to the surface. It is still thin compared to the old ROL gaskets by about .025". Calculate 21.25:1 ratio.
Carbon Fiber (old)-ROL Gasket. No longer Available 3mm material compressed to 2mm or .075" '93-'94 turbo motor standard equipment. CR 20.5:1
MLS would be hard to make work in our 18 year old + engines. .002" out of parallel over a 21" head
New Gasket Design
This gets to the point of what can be done in the market. Is it better to put a bigger gasket in the engine rather that deck the piston tops and raise the rings on the piston? The pistons will be double the price by the time they are decked and sealed around $200 each.
I have contacted every custom gasket manufacturing company on the internet I could find. Cometic would not return any of our calls and their design process is in the $4,000 range. England, South Africa, New Jersey, Lubbock, and finally Los Angeles.
There are two methods of reaching the 'thicker gasket'. One is a copper shim. The other is produce a thicker gasket.
The only company I found for the shim that won't kill us with development costs was in England.
Ferriday Engineering= http://www.ferriday.co.uk/copper/copper.shtml
#1= emails attached. They also have a 'helio flex' type gasket. More info to follow.But copper shims are their suggestion because we have cast iron block and heads and need the thickness to adjust the compression ratio.
#2= Best Gasket, Inc. in LA has produced gaskets for Perkins Saber Marine turbo diesels, and custom tractor gaskets, with a double fire ring that worked where OEM just leaked. They propose a gasket with a double layer sealed between with copper spray and a double fire ring. Email below:
Robb, here is a summary of our discussions, thus far…
Proposed gasket style:
2 layers of .048 steel reinforced graphite
Layers sealed together with Permatex Copper Spray-a-Gasket
Dual layer fire rings in combustion chamber (1st ring clinched around the 2 graphite layers, 2nd fire ring clinched over 1st ring)
Compressed thickness of .087 - .092” (we have no compression results for this style gasket)
Ballpark cost: $2000 tooling, $60 each ($120/pair)) for 25 pair minimum
Note: Our manufacturing methods allow for use of low cost tooling. Our head gaskets may have up to a .030” over target diameter at the y-axis. The x-axis diameter is accurate.
We look forward to providing a successful head gasket for your IDI turbo diesel engines.
Armin Brown
www.goofboard.com
Ferriday e-mail section. Read from bottom to top
To prevent a Mars lander kind of problem with conversion, are you calculating the shim thickness separate from the gasket? If so ending compression:
20.5:1 CR = .6mm shim +.9mm gasket = .024" shim + .035" gasket = 1.5mm, .06" total, about $437
19.1:1 CR = 1mm shim + .9mm gasket = .04" shim + .035" gasket = 1.9mm, .075" total, about $467
17.6:1 CR = 1.6mm shim + .9mm gasket = .063" shim + .035" gasket = 2.5mm, .098" total, about $490
less 20% (about 80$) for orders of 5 or more in the same thickness, or once you have the pattern you can cut it in any thickness, just groups of five?
Thanks for looking at this for us.
Robb
On Mon, Jan 9, 2012 at 3:48 AM, Mike Tanski <[email protected]> wrote:
Hi Robb,
OK, just to make things more difficult, even though I think in Imperial, I work in Metric.... So the 7.3 engine has 104.39mm bore x 106.17mm stroke. With a 23.0:1 CR, a 0.6mm shim = 20.5:1, 1.0mm = 19.1:1, and 1.6mm = 17.6:1. Figures for the 6.9 are so close as not to make any real difference.
These figures are assuming a factory engine with no changes to head gasket thickness or anything else, and to achieve the end CR that these figures indicate you must use a head gasket of the same thickness as was removed. But if any of your guys have already changed gasket thickness & want new figures, just let me know before & after thicknesses and desired CR.
As a guide, 0.6mm copper shims are £262.00, 1.0mm - £278.00 and 1.6mm = £294.00. These are for a pair of shims, based on an order of one pair only. I don't have drawings for these gaskets so will need you to send me OE type gaskets as patterns, there are no set-up charges involved.
If there were 5 or more pairs then around 20% can be deducted. Shipping may be around £25 per individual parcel, or around £80 for a few pairs to one address, though these are very vague until I know actual destinations. No taxes are to be added here, but some may apply at your end.
Copper spacers should be trouble free as long as both surfaces are good. The soft gasket still does all it's clever sealing to the block side, and clamping forces are transmitted through the shim to seal on the other side with the help of some non-setting sealant such as Blue Hylomar (I'd be happy to help you identify something similar that you can buy locally). Because the soft head gasket is still present, the difficulties experienced in sealing a solid copper (stand alone) gasket do not apply. The shim should be placed against the flattest surface, i.e. the head, as this should be freshly machined in order to do the job, with sealant between the head & shim,
Yea, we had a good ride out thanks. I'm part of a small but fairly active motorcycle Club, non of us are heroes but sometimes we press along quite well - the girls moan a bit, even though we always wait for them further along... We have some fantastic roads in this part of Wales, and very few police or cameras!
All the best Robb,
Mike
On 7 January 2012 17:33, robb willes <[email protected]> wrote:
Here is the text from my post off oilburners.
The math for the combustion chamber has been bugging me all day. Somebody check both the thought process and the math so we can come up with good numbers.
We are starting with a 7.3l, 444 cubic inch motor. Divide by 8 to determine starting volume for one cylinder, equals 55.5 inches^3.
-Divide volume by the compression ratio of 21.5 and the volume of the combustion chamber is 2.58 inches^3.
-Area of a circle is PiR^2. Bore diameter is 4.11 inches, Radius is 1/2 or 2.055. Area of the Bore is 2.055. *2.055^2*3.14156= 13.26 in^2.
-Area of the combustion chamber is 2.58 in^3 so chamber / by bore area = approx thickness in inches between head and piston top. 2.58/13.26=.1945 or about 195 thousandths.
-Gasket material makes up .030-.040, so without gasket we have .1545 thickness. A gasket with a .05 thickness would increase height to .2045 and the chamber to 2.712 inches^3. Divide that number into the original volume of the cylinder 55.5/2.712=20.46 compression.
-A .075 gasket to yield a combustion chamber of 3.284 in^3. 55.5/3.284 = 16.9 compression.
Room to deck the heads and still drop the combustion pressures at .075 thickness. Perfect for a .075 Garloc Helicoflex (someone else calls it Phew..., as in RnD fees really stinks up the place!) fire ring.
I think based on the Hypermax and VR designs with Carbon fiber, A carbon fiber gasket that compresses to .075 (starts at .125) if we can pair that with a .075 Garlock fire ring , the whole shebang would allow for old and new engines to get the upgrade and lower the compression. Seems like a win-win for all of us.
Mike, OK so new info, obviously, i gave you measurements for the for the whole thickness not the just the shim.
7.3=bore 4.11inch Stroke 4.18inch the 6.9 has 4.0 inch bore with the same stroke. Gasket measurement of 20.75 x 8 at the widest point which are the tabs for the coolant passages.
Will a copper spacer produce the same long term problems as a copper gasket, namely leakage (weeping) of antifreeze and oil?
What kind of ball park are we playing in, price wise. Sounds like shipping across 'the pond' might make all this a fruitless endeavor. Price point has been important in getting cooperation. A V-R gasket set that is made from carbon fiber is under $200. Cometic wanted $ 800 a set for Phuzion gaskets. There you have the price range.
The only other choice is a composite gasket. The thicker carbon fiber gasket is no longer available. MLS has never been made. My conclusion is that .002 max parallel out of head and block surfaces is not reliably obtainable on a 20+ year old engine that has 21 inch long heads. Thoughts?
Last 3 days here have been an Indian Summer. It was 65 day before yesterday. Went out riding in the woods and am nursing a snow-burn under the eyes. Hope you ride goes well.
On Sat, Jan 7, 2012 at 4:15 AM, Mike Tanski <[email protected]> wrote:
Hello Robb,
If you can tell me bore & stroke dimensions I'd be happy to do the maths for you, no other figures are needed unless the engines have been altered from stock, i.e. changes to piston or deck height, chamber volume etc. We'll also assume that an identical thickness head gasket will be used before & after plate fitment, but if further calcs are necessary let me know of any changes individually & I'll compensate.
I keep a basic range of sheet thicknesses in stock, but will be happy to get further thicknesses to get as close to your chosen CRs as possible. UK prices are often quite horrible compared to US... I've even seen completely finished products from the States for les than I can buy the raw materials, so I'm going to apologise for this in advance. But - if there is a small quantity ordered, then price will be very different from a prototype.
Please could you also let me know the length & width of each head gasket? Thanks.
Are these gaskets made from a Fibre type material, or are they Multi Layer Steel? And if OE ones are fibre, are MLS gaskets available aftermarket? If MLS, and depending on how the gasket is designed, it may be possible to incorporate a copper plate into the gasket itself, though I won't know until I inspect one.
As the entire engine is made from iron, the plate must be made from copper (if there was an aluminium alloy head we could consider an aluminium alloy plate).
All the best Robb, hope your weekend is going well. We're blessed with some nice weather today so I'm off on a run with my bike Club, gotta make the most of it, but I'm guessing I'll get wet at some point today, lol.
Mike @ Ferriday
On 5 January 2012 02:22, robb willes <[email protected]> wrote:
Mike,
Thanks for the info. Cometic seems to be very hard to work with. Lots of diffrent people have tried and they aren't responding. Seem not interested, we may be too small for their business model.
The oem compression ratio on the 6.9 and non turbo 7.3 was 23-1. The turbo had a thicker gasket supplied by ROL that seemed to be the only difference mechanically. End result was a 21.5-1 compression ratio for the turbo 7.3. The targets are 17-1 for sea level engines and 19-1 for those of us at Rocky Mountian altitudes. I have approximately calculated that a 70 thou thickness gets 19-1 and 90 thou gets 17-1 (although some people have decked pistons .1 inch trying to get 17-1) Head shims seem to be a great possibility to meet both with a standard VR gasket. Can you provide both versions? Could you verify compression calculations? Oilburners.net has a post on MLS gaskets where I calculated the combustion chamber size, but as its the first time I've done it, not sure if its right. A correct calculation that saves a trial and error process would help.
The head and block are both cast iron if that makes a diffrence.
Thanks, Robb
On Jan 4, 2012 2:15 AM, "Mike Tanski" <[email protected]> wrote:
Hi Robb,
Thank you for your e-mail, my apologies for the delay in responding.
It's unlibkely that my head gaskets will be suitable for your engines as they are made from solid materials and are not user-friendly in the way that softer "fibre" gaskets are. Also, they are only available in 26 or 40 thou thicknesses.
But, are you familiar with the concept of Decompression Plates (sometimes known as "Saver Shims")? There's some information attached that explains further, if you're happy with the Reinz gasket apart from the thickness (VR are original equipment to some big manufacturers) then this could be a possibility for you. I believe that Cometic make this type of product, would be worth contacting them again maybe?
Once you've read the info please come back to me if I can help further.
I hope you had a good Christmas, and that we all have a good 2012.
All the best Robb,
Mike Tanski
Ferriday Engineering
On 28 December 2011 22:38, robb willes <[email protected]> wrote:
Sirs,
I am part of a community that is rebuilding and tuning for performance our mechanically injected, International, diesel engines that were equipped in north American ford trucks through 1994. The head gasket seems to be a limiting factor in getting over 300 hp.
The head gaskets that were produced by ROL allowed for reduced compression (from 23 to 1 down to 21.5 to 1) in the 93-94 factory turbo diesels. ROL was sold to a Mexican manufacturer. DC Gaskets. DC Gaskets have eliminated this specialty gasket from their product list and are not importing to the US currently. We are looking for a supplier that can cope with our relatively small volume of 30 to 50 sets per year. Best case would be a gasket that runs in the 50 to 75 thousands (to reduce compression from 23 to 1 to about 19 to 1 or 17 to 1) range that also can cope with 2-3 atmospheres of boost. These trucks are daily drivers and work hard usually towing 5th wheel trailers. the hardened pre-injection cup that bisects where the head and block intersects complicates life pretty dramatically. The 'helicoflex' fire rings that are used by Cometic seem like a nice comprimise, but we have contacted Cometic and their "development" costs rankle many in the community. Add to that the 900$+ cost per engine of the proposed choices and it sends us looking for other options.
We work on these engines because we can get 'powerstroke' like performance out of a motor that costs $3-4k to rebuild vs the $10k of the 'powerstoke' with a much larger safety factor. A rebuild at 200k miles in most of these engines will still have the factory cross hatch and can be rebuilt 3 times for the cost of one 'powerstroke' failure. All this comes in the body style that was produced up to '99 that seems preferred by many Ford truck buyers.
Check out 'oilburners.net', 'powerstrokenation.com', and 'fordtruckenthusiast.com' to see some of the great engines that have been put together. I'm preparing to rebuild mine and hoping for a better option than the 35 Thou Victor-Reinz carbon fiber choice that is my best option now.
Any help or wisdom you could provide would be great
Skip down to "New Gasket Design" if you want just the new gasket stuff.
I want my truck to run for another 18 years before another major overhaul (I know wishful thinking!) so I want to get this gasket/stud/timing thing right. My conclusions about the weakness of the head gaskets in our engines has lead to a lot of reading both about the gaskets and the explosion that they are trying to contain. There is a great article at Oliver Diesel about the effect timing has on power transfer and emissions, http://www.oliverdiesel.com/tech/timing.htm.
Net result is that the more the engine timing is advanced the greater the amount of a cylinder pressure charge is transferred to the only thing that will move in that millisecond, the gasket. Add to timing setting the fact that our fuel injection system is mechanical, and so a weak injector means extra advance in that cylinder that is also fuel starved, a lean burn situation. In airplanes too lean a mixture will 'melt' pistons, and blow gaskets. Hypermax adds this warning on their performance carbon fiber head gaskets "Stacking of boxes will also fail the gasket. This means using an in-line programmer along with programming the factory PCM. This is due to the extreme timing advance that is produced by both modifications."
I think I created this situation on my truck when I had two injectors 'replaced' (no rebuild markings on them, so used?) at a shop shortly after I bought the truck and knew nothing about a idi diesel, add to that, I advancing the timing 2-3 dimes thickness, add to that towing a 15,000lb load of wood from Montrose to Colorado Springs (3 passes) and I get a gasket failure between the middle pistons on the passenger side at the last pass. Normal EGT were under 900 deg. I may have touched 1050 at the top of the passes but the gauge only shows an average of 8 cylinders. If I could have measured that one cylinder I believe it would have shown significantly higher.
Lesson#1: If I am running an advance on the timing pump I will always have my injectors pop tested to match each other. Then the timing for all the cylinders is the same! DPS shows $32 per injector x8= $256.
Head Studs or Bolts? The torque ratings on the 6.9 and 7.3 are different because of 7/16" (85-90lbs) vs 1/2" (105-115 lbs) studs. There were 180,000lb, 200,000lb and 220,000lb rated alloys made. The 220,000lb option was a failure as the studs would snap after a few heat cycles, from DPS's experience. Both bolts and studs are available in the lower rated alloys, online, but I wont trust steel from India in my truck. Some have said there is as much as 3 times the clamping force with the nut on a stud because there is less threads (1/2 an inch vs 1 1/2 inch) being twisted. Follow the 5-7 time tightening process outlined by head gasket manufactures and ARP to remove any gauling from the threads. Victor-Reinz says on their commercial site that bolts have a 30% error rate while the studs have only a 10%. ARP studs are available from TYPE4, last he posted around $400.
Biggest gain seems to come in the re-tightening of the nuts after the engine has been heated and cooled. On a side note I got almost a 1/8 extra turn on the 4.0 Jeep after running it once, didn't bother with the Audi as you have to take everything down including the intake manifold.
Gaskets Composite - Gaskets Carbon Fiber - Shims
Composite- Felpro Gasket. AutoZone $34 x 2, 1 year warranty. .035" thick. compressed ? Best description I have heard is a bunch of micro rubber like balls mixed up in a batch of asphalt like stuff and shaped into a gasket. If you could see one of those pressure maps that they have for all the foam beds there would be a pattern of hi-pressure dots and low pressure voids that cover the gasket. This is moderated by the rubber like coating that they put on the surface of the gasket. As engine pressure increases it is forced in between the micro-balls and erodes the goopy stuff. (high-tec description is free of charge) As the only difference I can see on the 7.3 turbo and non-turbo motors is the thickness of the head gasket, I think this gasket will raise the compression ratio back to the stock 23:1 compression ratio. Add more turbo and gasket problems will follow.
Carbon Fiber (new)- Victor-Reinz. Auto Zone $50 x , 2 year warranty. .05" thick out of the box. V-R says will compress 10% to .045". In concept the carbon fiber is like a very thick forest standing straight up. There is a perforated metal center plate that has two layers of carbon fiber. The fibers are different lengths and interlock as compressed. Each layer custom fits to the surface it mounts on. If you go back to the pressure map idea it will all shows the same pressure or color. No high spots or low voids. This doesn't compress as much as the old material and does conform to the surface. It is still thin compared to the old ROL gaskets by about .025". Calculate 21.25:1 ratio.
Carbon Fiber (old)-ROL Gasket. No longer Available 3mm material compressed to 2mm or .075" '93-'94 turbo motor standard equipment. CR 20.5:1
MLS would be hard to make work in our 18 year old + engines. .002" out of parallel over a 21" head
New Gasket Design
This gets to the point of what can be done in the market. Is it better to put a bigger gasket in the engine rather that deck the piston tops and raise the rings on the piston? The pistons will be double the price by the time they are decked and sealed around $200 each.
I have contacted every custom gasket manufacturing company on the internet I could find. Cometic would not return any of our calls and their design process is in the $4,000 range. England, South Africa, New Jersey, Lubbock, and finally Los Angeles.
There are two methods of reaching the 'thicker gasket'. One is a copper shim. The other is produce a thicker gasket.
The only company I found for the shim that won't kill us with development costs was in England.
Ferriday Engineering= http://www.ferriday.co.uk/copper/copper.shtml
#1= emails attached. They also have a 'helio flex' type gasket. More info to follow.But copper shims are their suggestion because we have cast iron block and heads and need the thickness to adjust the compression ratio.
#2= Best Gasket, Inc. in LA has produced gaskets for Perkins Saber Marine turbo diesels, and custom tractor gaskets, with a double fire ring that worked where OEM just leaked. They propose a gasket with a double layer sealed between with copper spray and a double fire ring. Email below:
Robb, here is a summary of our discussions, thus far…
Proposed gasket style:
2 layers of .048 steel reinforced graphite
Layers sealed together with Permatex Copper Spray-a-Gasket
Dual layer fire rings in combustion chamber (1st ring clinched around the 2 graphite layers, 2nd fire ring clinched over 1st ring)
Compressed thickness of .087 - .092” (we have no compression results for this style gasket)
Ballpark cost: $2000 tooling, $60 each ($120/pair)) for 25 pair minimum
Note: Our manufacturing methods allow for use of low cost tooling. Our head gaskets may have up to a .030” over target diameter at the y-axis. The x-axis diameter is accurate.
We look forward to providing a successful head gasket for your IDI turbo diesel engines.
Armin Brown
www.goofboard.com
Ferriday e-mail section. Read from bottom to top
To prevent a Mars lander kind of problem with conversion, are you calculating the shim thickness separate from the gasket? If so ending compression:
20.5:1 CR = .6mm shim +.9mm gasket = .024" shim + .035" gasket = 1.5mm, .06" total, about $437
19.1:1 CR = 1mm shim + .9mm gasket = .04" shim + .035" gasket = 1.9mm, .075" total, about $467
17.6:1 CR = 1.6mm shim + .9mm gasket = .063" shim + .035" gasket = 2.5mm, .098" total, about $490
less 20% (about 80$) for orders of 5 or more in the same thickness, or once you have the pattern you can cut it in any thickness, just groups of five?
Thanks for looking at this for us.
Robb
On Mon, Jan 9, 2012 at 3:48 AM, Mike Tanski <[email protected]> wrote:
Hi Robb,
OK, just to make things more difficult, even though I think in Imperial, I work in Metric.... So the 7.3 engine has 104.39mm bore x 106.17mm stroke. With a 23.0:1 CR, a 0.6mm shim = 20.5:1, 1.0mm = 19.1:1, and 1.6mm = 17.6:1. Figures for the 6.9 are so close as not to make any real difference.
These figures are assuming a factory engine with no changes to head gasket thickness or anything else, and to achieve the end CR that these figures indicate you must use a head gasket of the same thickness as was removed. But if any of your guys have already changed gasket thickness & want new figures, just let me know before & after thicknesses and desired CR.
As a guide, 0.6mm copper shims are £262.00, 1.0mm - £278.00 and 1.6mm = £294.00. These are for a pair of shims, based on an order of one pair only. I don't have drawings for these gaskets so will need you to send me OE type gaskets as patterns, there are no set-up charges involved.
If there were 5 or more pairs then around 20% can be deducted. Shipping may be around £25 per individual parcel, or around £80 for a few pairs to one address, though these are very vague until I know actual destinations. No taxes are to be added here, but some may apply at your end.
Copper spacers should be trouble free as long as both surfaces are good. The soft gasket still does all it's clever sealing to the block side, and clamping forces are transmitted through the shim to seal on the other side with the help of some non-setting sealant such as Blue Hylomar (I'd be happy to help you identify something similar that you can buy locally). Because the soft head gasket is still present, the difficulties experienced in sealing a solid copper (stand alone) gasket do not apply. The shim should be placed against the flattest surface, i.e. the head, as this should be freshly machined in order to do the job, with sealant between the head & shim,
Yea, we had a good ride out thanks. I'm part of a small but fairly active motorcycle Club, non of us are heroes but sometimes we press along quite well - the girls moan a bit, even though we always wait for them further along... We have some fantastic roads in this part of Wales, and very few police or cameras!
All the best Robb,
Mike
On 7 January 2012 17:33, robb willes <[email protected]> wrote:
Here is the text from my post off oilburners.
The math for the combustion chamber has been bugging me all day. Somebody check both the thought process and the math so we can come up with good numbers.
We are starting with a 7.3l, 444 cubic inch motor. Divide by 8 to determine starting volume for one cylinder, equals 55.5 inches^3.
-Divide volume by the compression ratio of 21.5 and the volume of the combustion chamber is 2.58 inches^3.
-Area of a circle is PiR^2. Bore diameter is 4.11 inches, Radius is 1/2 or 2.055. Area of the Bore is 2.055. *2.055^2*3.14156= 13.26 in^2.
-Area of the combustion chamber is 2.58 in^3 so chamber / by bore area = approx thickness in inches between head and piston top. 2.58/13.26=.1945 or about 195 thousandths.
-Gasket material makes up .030-.040, so without gasket we have .1545 thickness. A gasket with a .05 thickness would increase height to .2045 and the chamber to 2.712 inches^3. Divide that number into the original volume of the cylinder 55.5/2.712=20.46 compression.
-A .075 gasket to yield a combustion chamber of 3.284 in^3. 55.5/3.284 = 16.9 compression.
Room to deck the heads and still drop the combustion pressures at .075 thickness. Perfect for a .075 Garloc Helicoflex (someone else calls it Phew..., as in RnD fees really stinks up the place!) fire ring.
I think based on the Hypermax and VR designs with Carbon fiber, A carbon fiber gasket that compresses to .075 (starts at .125) if we can pair that with a .075 Garlock fire ring , the whole shebang would allow for old and new engines to get the upgrade and lower the compression. Seems like a win-win for all of us.
Mike, OK so new info, obviously, i gave you measurements for the for the whole thickness not the just the shim.
7.3=bore 4.11inch Stroke 4.18inch the 6.9 has 4.0 inch bore with the same stroke. Gasket measurement of 20.75 x 8 at the widest point which are the tabs for the coolant passages.
Will a copper spacer produce the same long term problems as a copper gasket, namely leakage (weeping) of antifreeze and oil?
What kind of ball park are we playing in, price wise. Sounds like shipping across 'the pond' might make all this a fruitless endeavor. Price point has been important in getting cooperation. A V-R gasket set that is made from carbon fiber is under $200. Cometic wanted $ 800 a set for Phuzion gaskets. There you have the price range.
The only other choice is a composite gasket. The thicker carbon fiber gasket is no longer available. MLS has never been made. My conclusion is that .002 max parallel out of head and block surfaces is not reliably obtainable on a 20+ year old engine that has 21 inch long heads. Thoughts?
Last 3 days here have been an Indian Summer. It was 65 day before yesterday. Went out riding in the woods and am nursing a snow-burn under the eyes. Hope you ride goes well.
On Sat, Jan 7, 2012 at 4:15 AM, Mike Tanski <[email protected]> wrote:
Hello Robb,
If you can tell me bore & stroke dimensions I'd be happy to do the maths for you, no other figures are needed unless the engines have been altered from stock, i.e. changes to piston or deck height, chamber volume etc. We'll also assume that an identical thickness head gasket will be used before & after plate fitment, but if further calcs are necessary let me know of any changes individually & I'll compensate.
I keep a basic range of sheet thicknesses in stock, but will be happy to get further thicknesses to get as close to your chosen CRs as possible. UK prices are often quite horrible compared to US... I've even seen completely finished products from the States for les than I can buy the raw materials, so I'm going to apologise for this in advance. But - if there is a small quantity ordered, then price will be very different from a prototype.
Please could you also let me know the length & width of each head gasket? Thanks.
Are these gaskets made from a Fibre type material, or are they Multi Layer Steel? And if OE ones are fibre, are MLS gaskets available aftermarket? If MLS, and depending on how the gasket is designed, it may be possible to incorporate a copper plate into the gasket itself, though I won't know until I inspect one.
As the entire engine is made from iron, the plate must be made from copper (if there was an aluminium alloy head we could consider an aluminium alloy plate).
All the best Robb, hope your weekend is going well. We're blessed with some nice weather today so I'm off on a run with my bike Club, gotta make the most of it, but I'm guessing I'll get wet at some point today, lol.
Mike @ Ferriday
On 5 January 2012 02:22, robb willes <[email protected]> wrote:
Mike,
Thanks for the info. Cometic seems to be very hard to work with. Lots of diffrent people have tried and they aren't responding. Seem not interested, we may be too small for their business model.
The oem compression ratio on the 6.9 and non turbo 7.3 was 23-1. The turbo had a thicker gasket supplied by ROL that seemed to be the only difference mechanically. End result was a 21.5-1 compression ratio for the turbo 7.3. The targets are 17-1 for sea level engines and 19-1 for those of us at Rocky Mountian altitudes. I have approximately calculated that a 70 thou thickness gets 19-1 and 90 thou gets 17-1 (although some people have decked pistons .1 inch trying to get 17-1) Head shims seem to be a great possibility to meet both with a standard VR gasket. Can you provide both versions? Could you verify compression calculations? Oilburners.net has a post on MLS gaskets where I calculated the combustion chamber size, but as its the first time I've done it, not sure if its right. A correct calculation that saves a trial and error process would help.
The head and block are both cast iron if that makes a diffrence.
Thanks, Robb
On Jan 4, 2012 2:15 AM, "Mike Tanski" <[email protected]> wrote:
Hi Robb,
Thank you for your e-mail, my apologies for the delay in responding.
It's unlibkely that my head gaskets will be suitable for your engines as they are made from solid materials and are not user-friendly in the way that softer "fibre" gaskets are. Also, they are only available in 26 or 40 thou thicknesses.
But, are you familiar with the concept of Decompression Plates (sometimes known as "Saver Shims")? There's some information attached that explains further, if you're happy with the Reinz gasket apart from the thickness (VR are original equipment to some big manufacturers) then this could be a possibility for you. I believe that Cometic make this type of product, would be worth contacting them again maybe?
Once you've read the info please come back to me if I can help further.
I hope you had a good Christmas, and that we all have a good 2012.
All the best Robb,
Mike Tanski
Ferriday Engineering
On 28 December 2011 22:38, robb willes <[email protected]> wrote:
Sirs,
I am part of a community that is rebuilding and tuning for performance our mechanically injected, International, diesel engines that were equipped in north American ford trucks through 1994. The head gasket seems to be a limiting factor in getting over 300 hp.
The head gaskets that were produced by ROL allowed for reduced compression (from 23 to 1 down to 21.5 to 1) in the 93-94 factory turbo diesels. ROL was sold to a Mexican manufacturer. DC Gaskets. DC Gaskets have eliminated this specialty gasket from their product list and are not importing to the US currently. We are looking for a supplier that can cope with our relatively small volume of 30 to 50 sets per year. Best case would be a gasket that runs in the 50 to 75 thousands (to reduce compression from 23 to 1 to about 19 to 1 or 17 to 1) range that also can cope with 2-3 atmospheres of boost. These trucks are daily drivers and work hard usually towing 5th wheel trailers. the hardened pre-injection cup that bisects where the head and block intersects complicates life pretty dramatically. The 'helicoflex' fire rings that are used by Cometic seem like a nice comprimise, but we have contacted Cometic and their "development" costs rankle many in the community. Add to that the 900$+ cost per engine of the proposed choices and it sends us looking for other options.
We work on these engines because we can get 'powerstroke' like performance out of a motor that costs $3-4k to rebuild vs the $10k of the 'powerstoke' with a much larger safety factor. A rebuild at 200k miles in most of these engines will still have the factory cross hatch and can be rebuilt 3 times for the cost of one 'powerstroke' failure. All this comes in the body style that was produced up to '99 that seems preferred by many Ford truck buyers.
Check out 'oilburners.net', 'powerstrokenation.com', and 'fordtruckenthusiast.com' to see some of the great engines that have been put together. I'm preparing to rebuild mine and hoping for a better option than the 35 Thou Victor-Reinz carbon fiber choice that is my best option now.
Any help or wisdom you could provide would be great
. Did you contact two seperate people? The Welsh guy seems to know his stuff...but the price is pretty darn high. Whats nice is the fact that we could pick which compression ratio we wanted. 
