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Hyper pistons and timing issues
#11
I really appreciate the time and effort that you all have put into this issue. I am sure it will help others as well. Probably most of us in the hobby are drivers rather than mechanics, so all the information provided is a great learning curve. Mistakes happen as in my case and the old adage " Wish I knew then what I know now" surely applies here. I'm a nuts and bolts sort of guy, but the fine points of tuning are out of my wheelhouse and sometimes relying on others advice can get one in trouble.............like me!!
Using UEM's compression ratio calculator for KB177 pistons with the numbers I was supplied, I get a static ratio of 10.56 and if I did it right, a dynamic ratio of 9.64. The cam chosen is a Melling MTF2 Hydraulic. Numbers are: cam lift int .281 & .296 exh. Valve lift, int. .486 & .512 exh. Lobe center 106 & 118, SAE duration, 282 int & 292 exh. .050 duration 204 & 214 Sae timing BTC 30, ABC 72, BBC 78 ATC 34 and .050 timing, BTC-4, ABC 28, BBC 45, ATC -11.
I find this cam to be quite good at low end torque and as the PerTronix III is still set at factory RPM limit of 5K, it has all the power I need for the very restricted driving we are allowed in Ontario. Any of you who have been here will know what I mean, low speed limits and "Stunt driving" laws......... 50 kms. ( 30 mph) over and lose your ride for a week plus big fines. Be warned guys if you plan on driving here!!
I am using a Holley 670 street avenger, which I have found to be quite efficient, gives good mileage and pulling power and my plug read on Autolite arf 42 plugs is a light tan and no sign of burning or other indications of trouble. As I said, if I accelerate gently, I can get the revs up without noticing the rattle, not saying it's not there, but I can't hear it. I do have a 160 stat in as I do quite a lot of parades and slow cruises. Also before I blocked off the heat riser passages in the factory intake, I was getting fuel evaporation. Blocking the riser and adding a 3/4" fiber spacer stopped that issue. I will go back to a 180 stat when I put the motor back together. Good tip!
As for the distributor, I do have a guy nearby who has a distributor machine and knows how to use it. I may just go aftermarket as I'm not into the concours thing, but do like the original look.
Geoff.
aka Stanglover.
  Reply
#12
Assuming the static compression ratio is 10.56, I get a dynamic ratio of 7.83 which should be fine if premium pump gas is used. It is about a half point higher than I'd use with iron heads and that cam. However, the DCR is an indicator, it is not an exact number indicating resistance to detonation. Things like combustion chamber shape, hot spots, and piston deck height play into the equation. Have you done a compression check on all 8 cylinders?

Chuck
  Reply
#13
c9zx;244978 Wrote:Assuming the static compression ratio is 10.56, I get a dynamic ratio of 7.83 which should be fine if premium pump gas is used. It is about a half point higher than I'd use with iron heads and that cam. However, the DCR is an indicator, it is not an exact number indicating resistance to detonation. Things like combustion chamber shape, hot spots, and piston deck height play into the equation. Have you done a compression check on all 8 cylinders?

Chuck

Thanks Chuck, The best gas I can get here is Shell 91 that does NOT have ethanol in it. I can get 94 from Petro-Can, used to be Sunoco, but since the take over, 10% ethanol was added. Ethanol is a big con if you ask me and really has very little value other than to screw us. That's just my opinion.
I did do a compression pressure check, lost the paper I wrote it down on, but the range was between 195 and 210psi. The heads are D0AE-GA which are supposed to be about 62.8cc. Obviously as castings, the actual volume can and likely do vary which would account for differences. Could be leakage too I know. I don't have the equipment to do a leak-down test.
I'm not sure how you arrived at the dynamic number whereas the chart asks for rod length @5.778" and intake closing point, ABDC @.050 lift plus 15 deg 28+15 =43??. Your knowledge here would be very helpful.
The actual deck height is a bit of a guess. Stock was .028". I do not know what was milled off either block or heads in truing, but as a retired machinist, I would think 3-5 thou off each. The KB177 are .020" higher, so that would put the deck at about .003 -.005.It was never measured or at least passed on to me. Other variables could be in there too I know. The gasket is compressed at .039" (ish)
At the end of the day, the info I need is the best piston to build a 10.0:1 engine that I can run all day on 91 octane fuel and what setting should I aim for on a distributor, stock or otherwise.
Thank you again,

Geoff.
  Reply
#14
.
it is impossible to give you an accurate answer without your current head cc and the deck height and the piston volume.

obviously, if you put a piston in that has a 20 cc dish in it, it will not detonate, however, if you want the best and most accurate info, and the most power, we need these numbers.

if the new pistons are below the deck and you dont want to mill the block, you can buy thinner head gaskets from cometic . . they make .036" and .027" . . i would use the one that gets you closest to, but no less than .035" quench/squish clearance . . more than .042 is getting a little big.

valve lift has absolutely nothing to do with the intake closing time . . the cam card should tell you exactly what it is and you posted it is 72 degrees abdc.

the calculators for dynamic compression are estimates . . you can have two different cams with the same ivc time but both can have different dynamic compression if other things such as overlap and lift etc are different.

there is a clip in the top of the dist shaft that holds the mechanical advance unit on . . remove the points plate then that clip then lok at the advance unit . . there will be a slot on both sides around 1/2" long . . on top of the slot there will be a number . . one side will be higher than the other . . they are often 10 on one side and 12 or 15 on the other . . there will be an arm in just one of the slots . . this limits the advance . . if you double the number on the slot, that ill be how much mechanical advance it will add when the limiting arm is in that slot.

in your case, with around 9.5 compression and .035 to .042 quench/squish clearance, i would put the arm in the 10 slot if you have one, then remove the heavier/stiffer of the two advance springs and replace it with a mr gasket 925d spring . . i would then set my initial timing to 10 degrees btdc and try that.

if you need to change the limiting arm to the other slot, simply lift up on the advance unit after you removed the clip in the top of the shaft.

disconnect and plug the vacuum advance unit until your car runs perfectly then set it to add only 5 to 6 degrees of advance . . if it is not adjustable you will need to buy an adjustable one and plug it into ported vacuum.
.

it
  Reply
#15
Stanglover;244983 Wrote:
c9zx;244978 Wrote:Assuming the static compression ratio is 10.56, I get a dynamic ratio of 7.83 which should be fine if premium pump gas is used. It is about a half point higher than I'd use with iron heads and that cam. However, the DCR is an indicator, it is not an exact number indicating resistance to detonation. Things like combustion chamber shape, hot spots, and piston deck height play into the equation. Have you done a compression check on all 8 cylinders?

Chuck

Thanks Chuck, The best gas I can get here is Shell 91 that does NOT have ethanol in it. I can get 94 from Petro-Can, used to be Sunoco, but since the take over, 10% ethanol was added. Ethanol is a big con if you ask me and really has very little value other than to screw us. That's just my opinion.
I did do a compression pressure check, lost the paper I wrote it down on, but the range was between 195 and 210psi. The heads are D0AE-GA which are supposed to be about 62.8cc. Obviously as castings, the actual volume can and likely do vary which would account for differences. Could be leakage too I know. I don't have the equipment to do a leak-down test.
I'm not sure how you arrived at the dynamic number whereas the chart asks for rod length @5.778" and intake closing point, ABDC @.050 lift plus 15 deg 28+15 =43??. Your knowledge here would be very helpful.
The actual deck height is a bit of a guess. Stock was .028". I do not know what was milled off either block or heads in truing, but as a retired machinist, I would think 3-5 thou off each. The KB177 are .020" higher, so that would put the deck at about .003 -.005.It was never measured or at least passed on to me. Other variables could be in there too I know. The gasket is compressed at .039" (ish)
At the end of the day, the info I need is the best piston to build a 10.0:1 engine that I can run all day on 91 octane fuel and what setting should I aim for on a distributor, stock or otherwise.
Thank you again,

Geoff.

I calculated the DCR using the Wallace racing calculator (online). I first calculated the Intake closing point like this, Lobe Separation Angle (LSA) is 117-107=10, divided by two=5, 107+5=112 LSA (same as averaging 117 and 107). ADV. INT. Duration divided by two + LSA - any ground in advance, -180=Intake closing point in degrees.
So, 282/2=141+112-0-180=73 degrees after bottom dead center, I assumed 0 degrees ground in advance.

Ethanol in gasoline is a giant scam perpetrated by ignorant governments, corn producers, and refiners. A casual analysis of the FACTS reveals this very quickly. I'll stop there so I don't get a warning.Tongue

As to pistons, any quality forged 4032 aluminum flat top piston and ring package will work assuming proper gaps and installation. My current personal favorite is Mahle, if they have what you need. In my opinion their quality and machining tolerances are superior. They are relatively light and their ring lands and ring packages are superior (the ring land is a compression sealing surface). Others would be JE/SRP, Diamond, even Sealed power is fine for what you are doing.
Any piston replacement will almost certainly require rebalancing the rotating assembly.

After writing all of the above, I re-read you post on compression test results. A variance of 7 percent means the ring sealing (and valve sealing) is still good. You may just need to get a proper curve in the distributor. As to general distributor calibration; Initial timing with no mechanical advance in play (very low idle speed) set to 16. Total mechanical advance set to 20 degrees for a total of 36 degrees mechanical advance. All mechanical advance should be in by about 2700-2800 RPM (I'm assuming you are not using a 2.78ish rear gear). If vacuum advance is used, limit it to 8-10 degrees. You are fortunate to have access to someone who knows how to curve a distributor.

Good luck and let us know what you end up doing and the results. Chuck
  Reply
#16
c9zx;245020 Wrote:
Stanglover;244983 Wrote:
c9zx;244978 Wrote:Assuming the static compression ratio is 10.56, I get a dynamic ratio of 7.83 which should be fine if premium pump gas is used. It is about a half point higher than I'd use with iron heads and that cam. However, the DCR is an indicator, it is not an exact number indicating resistance to detonation. Things like combustion chamber shape, hot spots, and piston deck height play into the equation. Have you done a compression check on all 8 cylinders?

Chuck

Thanks Chuck, The best gas I can get here is Shell 91 that does NOT have ethanol in it. I can get 94 from Petro-Can, used to be Sunoco, but since the take over, 10% ethanol was added. Ethanol is a big con if you ask me and really has very little value other than to screw us. That's just my opinion.
I did do a compression pressure check, lost the paper I wrote it down on, but the range was between 195 and 210psi. The heads are D0AE-GA which are supposed to be about 62.8cc. Obviously as castings, the actual volume can and likely do vary which would account for differences. Could be leakage too I know. I don't have the equipment to do a leak-down test.
I'm not sure how you arrived at the dynamic number whereas the chart asks for rod length @5.778" and intake closing point, ABDC @.050 lift plus 15 deg 28+15 =43??. Your knowledge here would be very helpful.
The actual deck height is a bit of a guess. Stock was .028". I do not know what was milled off either block or heads in truing, but as a retired machinist, I would think 3-5 thou off each. The KB177 are .020" higher, so that would put the deck at about .003 -.005.It was never measured or at least passed on to me. Other variables could be in there too I know. The gasket is compressed at .039" (ish)
At the end of the day, the info I need is the best piston to build a 10.0:1 engine that I can run all day on 91 octane fuel and what setting should I aim for on a distributor, stock or otherwise.
Thank you again,

Geoff.

I calculated the DCR using the Wallace racing calculator (online). I first calculated the Intake closing point like this, Lobe Separation Angle (LSA) is 117-107=10, divided by two=5, 107+5=112 LSA (same as averaging 117 and 107). ADV. INT. Duration divided by two + LSA - any ground in advance, -180=Intake closing point in degrees.
So, 282/2=141+112-0-180=73 degrees after bottom dead center, I assumed 0 degrees ground in advance.

Ethanol in gasoline is a giant scam perpetrated by ignorant governments, corn producers, and refiners. A casual analysis of the FACTS reveals this very quickly. I'll stop there so I don't get a warning.Tongue

As to pistons, any quality forged 4032 aluminum flat top piston and ring package will work assuming proper gaps and installation. My current personal favorite is Mahle, if they have what you need. In my opinion their quality and machining tolerances are superior. They are relatively light and their ring lands and ring packages are superior (the ring land is a compression sealing surface). Others would be JE/SRP, Diamond, even Sealed power is fine for what you are doing.
Any piston replacement will almost certainly require rebalancing the rotating assembly.

After writing all of the above, I re-read you post on compression test results. A variance of 7 percent means the ring sealing (and valve sealing) is still good. You may just need to get a proper curve in the distributor. As to general distributor calibration; Initial timing with no mechanical advance in play (very low idle speed) set to 16. Total mechanical advance set to 20 degrees for a total of 36 degrees mechanical advance. All mechanical advance should be in by about 2700-2800 RPM (I'm assuming you are not using a 2.78ish rear gear). If vacuum advance is used, limit it to 8-10 degrees. You are fortunate to have access to someone who knows how to curve a distributor.

Good luck and let us know what you end up doing and the results. Chuck

Chuck, I can't thank you ( and everyone else) enough for your time and effort you have put into this issue. I will certainly be taking your suggestions into consideration when I do the re-build. I am hoping that my date correct original block is still salvageable. If not I have 2 other blocks that are at least date appropriate. There is no VIN number on my block, so close may have to good enough.
The car has a 3.25:1 open rear end which is hard to believe Ford put open difs in the Mach1's
I will post the results when I get the re-build done and that likely won't be till Spring as it's about time to put the car away for winter. I will also post some more pictures to my album when I get time to work on it.
Thanks again,
Geoff.
  Reply
#17
My engine sat dormant for 30ish years, with #4 and #8 seized in the holes. It would've only required .020" bores if it weren't for the rust and scarring in the cylinder walls (.060" got me through). So, mine is still "numbers matching" as well (except for the AOD instead of the FMX, that is).


.jpg   engineold.jpg (Size: 127.67 KB / Downloads: 177)

   

Your engine should be fine, in other words. thumb

Those are the KB hyper pistons, as well. Wink



And Yes... I know it's the 'wrong' color. whistling

Eric

[Image: mach1sig2.gif]
  Reply
#18
Mister 4x4;245070 Wrote:My engine sat dormant for 30ish years, with #4 and #8 seized in the holes. It would've only required .020" bores if it weren't for the rust and scarring in the cylinder walls (.060" got me through). So, mine is still "numbers matching" as well (except for the AOD instead of the FMX, that is).





Your engine should be fine, in other words. thumb

Those are the KB hyper pistons, as well. Wink



And Yes... I know it's the 'wrong' color. whistling

Hi Eric, Thank to you to for your time. Interesting that you went to .060 over. I thought that would be pushing it for a Cleveland, but I guess if there is no core shift and the thickness is consistent, why not!
I am hesitant to go that far, but yes it is an option to save the block... at least for a while. Also notice you have a valve stem guide plate installed for a roller cam. Nice pictures by the way. If you're building a custom, why not chose a color you like, nothing wrong with that.
Geoff.
  Reply
#19
Stanglover;245103 Wrote:Hi Eric, Thank to you to for your time. Interesting that you went to .060 over. I thought that would be pushing it for a Cleveland, but I guess if there is no core shift and the thickness is consistent, why not!
I am hesitant to go that far, but yes it is an option to save the block... at least for a while. Also notice you have a valve stem guide plate installed for a roller cam. Nice pictures by the way. If you're building a custom, why not chose a color you like, nothing wrong with that.
Geoff.

The machinist initially went .020" and noticed scars on the cylinder walls of #4 & #8 from where the pistons had been rusted in-place for so long. Then went .040", and although diminished, the scars were still there. So, they went .060" and the scars were finally gone. The next step would've been sleeving the offending cylinders, but I wasn't so keen on that. Now that I know more about the sleeving process, and seeing the factory cross-hatching in the cylinder walls of my '95 Honda Civic with 192K miles, I'm thinking I'll be OK to sleeve ALL of the cylinders if this engine gets worn out in the future.

Anyway, the machinist called me between each step, of course, and asked what I wanted to do - since I'd noticed the .060" KB pistons on Summit Racing's website, I didn't have any problems going that big. A lot of folks jumped in with their opinions about Clevelands not handling .060" bores, but I choose to believe that if it was such a problem, there wouldn't be .060" pistons so readily available. They key is to keeping the engine running at consistent temperatures within normal operating ranges - frequent and extreme overheating compounded with the larger bores will kill the Clevelands quicker than anything.

I actually performed the "Pantera" cooling trick a few weekends ago, and it made a big difference - the temp gauge needle so far hasn't made it past the space between the "O" and "R" of "NORMAL." Before I made the change, if I left it idling too long, it would get a LOT warmer (up to the "A" and beyond), mostly because the local parts store gave me a non-Cleveland thermostat, so the cooling system wasn't working right from the beginning. A new thermostat and bypass restrictor plate from West Coast Cougar Classics solved that issue.

The color is actually Duplicolor "Old Ford Blue" engine enamel. I just happened to grab it, rather than the Corporate Blue - which honestly, appeals to me better than the Corporate Blue.

Eric

[Image: mach1sig2.gif]
  Reply
#20
Stanglover;245103 Wrote:Hi Eric, Thank to you to for your time. Interesting that you went to .060 over. I thought that would be pushing it for a Cleveland, but I guess if there is no core shift and the thickness is consistent, why not!
I am hesitant to go that far, but yes it is an option to save the block... at least for a while. Also notice you have a valve stem guide plate installed for a roller cam. Nice pictures by the way. If you're building a custom, why not chose a color you like, nothing wrong with that.
Geoff.

you should always bore the least amount possible not only to make it easier to cool but also so you will have another bore r two left.

if you need an odd size like .045 to keep from going to .060, you can get custom pistons made from race tec . . the 4032 ones are only $575.00 . . thats only $75.00 more than probes and around the same as SRP's.
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