DIY Naturally Aspirated 6.2L Build

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bubblehead93

bubblehead93

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So I promised a little rod balancing how to... there are a few good YouTube videos on piston and rod balancing...

First you need a scale, i picked up a couple cheap Chinese ones on Amazon that could read to 0.01 grams... these work like a champ... remember you don't care about absolute weight when balancing pistons and rods, just relative weight, you want precision and repeatability not accuracy. The guy balancing your crank, he cares about accuracy and precision, so his scale costs much much more so he can get the bob weights right. What you care about is not if the big end of your rod weighs 450.0 grams, you care that when you put the rod on the scale it always measures 450.0 grams and if you put another rod on there whose big end was 450.0 grams it would weight 450.0 grams as well. If you then put the two rods in a fixture on an expensive more accurate scale that indicated 446.0 grams, again, important info the guy balancing your crank, however, that accuracy does not give you anything more than you already had. Your just trying to match relative weights.

That being said, I have a little weight set for calibrating up to 1000 grams. So before each use I calibrate for a weight near what I'll be measuring. I then don't calibrate again until I'm done. If I do, I'll start from scratch... since I'm likely changing the relative zero, again its all about relative weights, accuracy is not so much important.

Using the rod balancing fixture you weigh all the big ends. You find the lightest rod big end, figure out how many grams have to be removed from each of the other rods to match the lightest big end, and then remove material by chamfering rod around the rod bolts as shown in the picture in my earlier post using a vertical belt sander. I frequently cross check back to my lightest rod to make sure apples-to-apples. A little material goes a long way with rods, as compared to pistons made of aluminum. Once I think I've matched all the big ends, I weigh all the big ends again to ensure repeatability. The fixture is very sensitive to setup. Make sure as you put the rod on and pull off that the fixture remains centered on the scale, the rod is square in the fixture, and that each rod sits on the roller bearings precisely the same. OCD is critical here to get repeatable results down to a +/-0.1 grams. The goal is everything within +/-0.1 grams of each other.

Then you need to weigh all the rods, no fixture. Again find the lightest rod. Because I'm OCD I also weighed the small end in the fixture on each rod as you would expect the delta to be the same. I like cross checks. In theory, any difference in rod weight at this point should be the small end. So again, using the vertical belt sander you remove material circumferentially around the small end. Again a little goes a long way with steel. You match all of the other rods to the lightest overall rod. Once you think they are matched, weigh them all again. Then weigh all the big ends again. Final cross check.

Now you have a balanced set of rods...
 
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bubblehead93

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P.S. Most of the rod big ends were within 1 gram of the lightest rod big end, my #1 was the lightest big end... there is always an outlier though, rod #3 was the heaviest big end by a little over 2 grams. Once all the big ends were matched, for o/a weight, rod #5 was the lightest rod with rod #6 requiring a smidge over 2 grams off the small end. All the other rod small ends were within 1 gram of the lightest rod. Be it pistons, wrist pins, or rods...most are close to each other in weight BUT there always seems to be an outlier...
 
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bubblehead93

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Got word from DCR that the re-ground cams have shipped... wohoo! Should get here next Monday via UPS!

Interesting piece, the Manley lightweight rods do not take 6.2L rod bearings... I had a single pair of 6.2L rod bearings laying around and while they physically fit, the tangs are not in the right place, so after installing the 6.2L rod bearings you can see they are not centered in the bore and the bearing halves are offset...

Gave Manley Tech Support a call, sure enough, the rods take a 4.6L bearing, they quoted Clevite 1442P... good news because there are more performance options with 4.6L rod bearings... bad because I'm pretty sure I'm going to have to mess around with different size 4.6L bearings to get the oil clearance set right...

So 1442P which was a TM-77 bearing was superseded by the 1442A but its a AL-5 bearing... the 1442HN is the currently available TM-77 rod bearing (or 1422HNC if you want a dry coated bearing.

So the 1442HN STD specs are...

Rod big end diameter: 2.2388-2.2396 inches
Crank rod journal diameter: 2.0859-2.0867 inches
Wall thickness: 0.0759 inches
Width: 0.8270 inches (21 mm)

My machinist still has the crank and reports it just needs a polish... so pretty close to stock dimensions...

By comparison the TM-77 for the stock 6.2L rod bearing is a 1944H...

Rod big end diameter: 2.2388-2.2396 inches
Crank rod journal diameter: 2.0761-2.0768 inches
Wall thickness: 0.0758 inches
Width: 0.8583 inches (21.8 mm)

So the crank rod journal specs are a bit different... 0.0091-0.0108", so approximately 0.01"

Have a few different sized sets on order (STD, 0.25 mm, and 0.50 mm) to make sure I have what I need... should be here end of the week... take some measurements... does not matter what numbers come out of the catalog, I know the oil clearance I want, so installed inside rod bearing measurements will show me the way...
 
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bubblehead93

bubblehead93

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Got word from DCR that the re-ground cams have shipped... wohoo! Should get here next Monday via UPS!

Interesting piece, the Manley lightweight rods do not take 6.2L rod bearings... I had a single pair of 6.2L rod bearings laying around and while they physically fit, the tangs are not in the right place, so after installing the 6.2L rod bearings you can see they are not centered in the bore and the bearing halves are offset...

Gave Manley Tech Support a call, sure enough, the rods take a 4.6L bearing, they quoted Clevite 1442P... good news because there are more performance options with 4.6L rod bearings... bad because I'm pretty sure I'm going to have to mess around with different size 4.6L bearings to get the oil clearance set right...

So 1442P which was a TM-77 bearing was superseded by the 1442A but its a AL-5 bearing... the 1442HN is the currently available TM-77 rod bearing (or 1422HNC if you want a dry coated bearing.

So the 1442HN STD specs are...

Rod big end diameter: 2.2388-2.2396 inches
Crank rod journal diameter: 2.0859-2.0867 inches
Wall thickness: 0.0759 inches
Width: 0.8270 inches (21 mm)

My machinist still has the crank and reports it just needs a polish... so pretty close to stock dimensions...

By comparison the TM-77 for the stock 6.2L rod bearing is a 1944H...

Rod big end diameter: 2.2388-2.2396 inches
Crank rod journal diameter: 2.0761-2.0768 inches
Wall thickness: 0.0758 inches
Width: 0.8583 inches (21.8 mm)

So the crank rod journal specs are a bit different... 0.0091-0.0108", so approximately 0.01"

Have a few different sized sets on order (STD, 0.25 mm, and 0.50 mm) to make sure I have what I need... should be here end of the week... take some measurements... does not matter what numbers come out of the catalog, I know the oil clearance I want, so installed inside rod bearing measurements will show me the way...
I just wanted to add a couple pictures demonstrating the issue. The following is a 6.2 rod bearing installed in a Manley rod:
186B3C6D-F3E1-4825-AC46-67CDDD509976.jpeg
And then you have the 4.6 rod bearing in the same rod:
9BE5A3CB-62B2-4143-AC83-9835C7F249E7.jpeg
Initial quick measurements look good from an oil clearance perspective at std size. Fiddle with it a bit more this weekend…
 

Canuck714

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Great info BH93... Did you send DC a set of Raptor cams or 2018 F250 cams to get ground?
I was just talking with him the other week, seems like a smart fella. I asked which cams he wanted and he said send both for him to loook at..lol
 
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bubblehead93

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I know he wrote 2018 Ford 6.2 on the cam card so it seems a bit confusing...

I sent him F150 cams... i imagine F150 and F250 cams, though different, must be ground from the same cores... since the F150 cam is the more aggressive of the two I would go that way... all cost about the same... my fear is there is less lobe for him to play with on the F250 version... i'll be honest i don't know the specs on the F250 cams but since its flex fuel capable it has to be a bit milder...

Part Number​
Part Name​
Price​
Quantity​
Total​
AL3Z-6250-E​
Engine Camshaft - Driver's Side (LH)​
$108.14​
1​
$108.14​
AL3Z-6250-F​
Engine Camshaft - Passenger Side (RH)​
$105.88​
1​
$105.88​
Subtotal: $214.02​
Estimated Shipping to 29483 via Standard Shipping: $33.22​
Tax: $17.30​
Total: $264.54​
 
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bubblehead93

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I know Canuck714 knows this but for others who are trying to sort things out on a 6.2, there really is not an OEM Raptor Cam. There is a F150 and a F250/350 cam. Any Ford F150 with a 6.2 had the same camshaft and same motor ratings. I wish I could get my hands on an old set of M-6550-RXT (F150 Camshaft Ford Performance Parts Performance Parts - Intake/Exhaust Duration 263/288 Degrees - Lobe Separation 118 Degrees - Lift Remains Stock).
 
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bubblehead93

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getting ready to baseline the current setup at a local dyno shop... while I wait on machine work to get done... 94K mile stock motor with S&B intake, SW long tubes/dual exhaust, and a VMP 93 octane tune... with the rear diff locked on 35x12.50x17 Nitto Mud Grapplers (traction limited) rips consistent 6.2-6.3 sec 0-60 mph (Car and Driver says stock is 6.6 sec)... most of that is likely due to the traction bars and better shifting/throttle response due to the tune... be interesting what the dyno will say... hopefully 340-350 rwhp... but we'll see...
 
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