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Building and Blueprinting a Road Race Motor (mini-build thread)

captdistraction

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Are you going to flip the one secondary chain tensioner upside down? Was it driver's side?
I have the part for it sitting here, but damn if I'm not terrified of anything MMR. This thing is fairly universally recommended, but my past is a cautionary tale when it comes to their stuff.

So will have to start making these parts decisions soon
 

steveespo

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I did the secondary chain tensioner on the 21 car CJ cam rebuild and 10 hours in so far so good. The mmr part is only a billet retainer that holds the tensioner in place and is secured with the mega cap bolts. The theory is sound.


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captdistraction

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What is the issue with respect to the MMR parts? I have that MMR part ready for install along with their tensioners and HD secondary chains and billet crank sprocket.
they have a reputation for making something and getting it to market without testing. Most of my troubles with those guys were from their service side building engines with bad clearances, or using known bad parts in a rebuild to save money/increase profit. From a parts perspective, I've bought a set of torque plates that were too tall for a coyote (and didn't cover the deck properly), an external oil filter adapter (which didn't clear an alternator - they later revised this part) and a few other things over the years. That said, this secondary bracket does seem to be well recommended.

I did the secondary chain tensioner on the 21 car CJ cam rebuild and 10 hours in so far so good. The mmr part is only a billet retainer that holds the tensioner in place and is secured with the mega cap bolts. The theory is sound.


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That's comforting to know. Is there plenty of thread engagement with the mega cap bolts? Or should I track down a couple longer ones?
 

captdistraction

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This has again been stalled while life's priorities are elsewhere, but I'm trying to get things on track. The machinist moves very slow, he's only finished the torque plates so far, and issues with his hone and the Arizona summer have held up the process significantly. Current estimates are looking into November for a shortblock to be assembled, but in the interim have picked out some new parts (and will update the original post):

-FPP M-6067-M52S cam covers - aluminum (from GT500 program - very trick parts, nicer baffling than the Gen2 plastic valve cover, additional ports, aluminum construction)
-FPP M-6207-M52 - Secondary chain guides (from GT4)
-JPC aluminum primary chain guides (tensioned and fixed) - previously had just purchased the tensioned side
-JPC cobrajet aluminum blockoff plates (to block off evap and PCV unused connections)
-all parts to do a true -12AN feed into a watson can, with a -6AN return line off the drain


If there's no movement on the motor (which looking back I mentioned it was finally moving in February, here we are 7 months later with no machining done on the block still), I may start investigating a 5.2L block, as they are supposedly finish honed and torque-plated from the factory.
 

TymeSlayer

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Sometymes you start feeling like you're poking a dead horse with a stick yet knowing full well it won't get up and run.

Hang in there Captain, endeavor to persevere.
 

OCPONY

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I have the part for it sitting here, but damn if I'm not terrified of anything MMR. This thing is fairly universally recommended, but my past is a cautionary tale when it comes to their stuff.

So will have to start making these parts decisions soon

I installed the MMR secondary chain tensioner back in 2016 on my 5.2L CPC build. Completing its 3 season and 36,000+ miles now. Ran Daytona in April this year on 125 shot nitrous hitting 172mph. Also been to 8300 rpm in 5th at TX mile on the nitrous. 187.7 mph. Was going to do tear down this year but its still hauling the mail!!
 

OCPONY

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Update 3: Valvetrain Setup.

Continuing the processes of measuring everything carefully, I tore down some new-in-box boss 302 CNC cylinder heads to upgrade the valve springs and retainers (and additionally some arp cam tower bolts to replace the small torque to yield bolts that are truly meant for one use only).

Valvespring Selection

I selected the PAC Racing Springs 1234x Coyote Drop-In spring. Drop in means that it should be install-able without significant need to measure or shim the spring or use an aftermarket retainer or base.

The stock boss spring has an installed height of 40mm or 1.575". The rate is supposedly 67lbs at installed height, and 157lbs at open (which is undefined). Rate is approx 190 lb-in (anyone feel free to correct me, math feels rough here)
The PAC spring has a similar install height (I did measure a slightly taller difference due to the titanium retainer design being different than oem). 92lbs at installed height of 1.575 (mine was 1.585), and the open height of 1.050 has a load of 218 lbs for a rate of 240lbs-in.

These rates come into importance when dealing with aftermarket cams which can have different ramp rates. I'm using an OEM boss exhaust cam, but a custom L&M intake cam (Which is similar to stock with slightly moved events).

The weights are also different: the Factory spring and retainer weighed in at 1.73 ounces, the PAC spring and titanium retainer weigh in at 1.52 ounces. Hopefully shedding 6.72 ounces from the valve train proves beneficial.



This is some info I got from Ford engineer. He suggested I use the 1733 springs on a 1000 whp 2012 Boss twin hellion build I am working on for a TX Mile Car. We are retaining the full VCT and the PAC 1234x spring I Asked him about gave him some pause but they are also using a similar spec rated spring for the GT350 heads and not having issues with VCT. It has 80lb closed pressure and 225lb rate. Livernois list a TVS-1733 spring...but PAC said it was proprietary for Livernois. PAC didn't list PAC spring of their own with 1733 part number or anything with same specs.

"Looking through my notes, I believe the 1733 is a PAC spring, but Livernois must put the 1733 part number on it.




Boss spring: 68lb closed, 170lb open, 200lb rate, 43g……peak rpm ~7800


1733: 69lb closed, 173.5lb open, 204lb rate, 38.3g……..peak rpm ~8400


1234: 94lb closed, 208.4lb open, 224lb rate, 38.7g……..peak rpm ~8850




I thought the 1733 spring was a bit higher than what I’m showing above. The 1733 spring is 5g lighter than the Boss spring, so that is very helpful."


I hope that gives you some good info. I will see if he can give me any info on the oil gallery being tied together.

The Livernois page specs show TVS 1733 springs as:
Install Height: 1.575


Max. Valve Spring Lift: .580


Spring Pressure Closed: 75lbs


Spring Pressure Open: 175


Coil Bind: .950

Which is a little higher closed pressure probably what the engineer was thinking when he suggested them.




FP350S oil galley mystery:

I have also been looking at why Ford Performance chose to tie the left and right heads together at the backs of the oil galleys (from intake side to intake side and exhaust to exhaust with hard -6 AN line). Its definitely a balance thing, however I'm working to get answers. I have validated that common 3/8" NPT to -6AN adapters fit well in this application for the threaded ports on the heads, but I until I get a final word from FPP (who have no reason to provide any useful information), I'll leave the heads alone.

View attachment 7822
 
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captdistraction

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Good info, and spring pressures get interesting in boosted applications for sure.

Updates on my build:

The MMR brackets won't work for me: with the new GT4 "snubbers" or guides there's a new retention mechanism that keeps the guide in line with the chain. Its incompatible with the MMR bracket without machining it significantly so I sold it as I found more value in the FPP parts than MMR (though as others mentioned, its sound design and application).

IMG_4548.jpg IMG_4549.jpg IMG_4551.jpg IMG_4553.jpg IMG_4555.jpg IMG_4556.jpg IMG_4557.jpg

On the block:

It went in for honing and we very carefully discussed the uber-tight clearances (piston to wall) yet again with Mahle before firing up the hone. the range was 7 to 13 tenths (ten-thousandths), but a sheet in the box mentioned adding 5 to 15 tenths for racing use. We did validate that it does not apply to the M142P pistons (but does apply to the 2618 pistons), and for a racing engine, they'd like as close to 1 thousandth TOTAL as possible, not exceeding 15 tenths TOTAL clearance. So again very tight tolerances compared to many other options.

IMG_4782.JPG


Bill Day (the builder) took the block through a honing program that took a week. With the torque plates installed he'd take a couple ten-thousandths out, let it rest, measure it and then take another tenth out; repeating until he hit the target. He mentioned many builders will do the honing in one pass and while that gets close, the honing procedure introduces heat (obviously), pressure, and can lead to imperfect measurements. I think for many varying a tenth here or there isn't a big deal, but for Bill he wanted the cylinders perfect so that's what he did.

So we are dead on round on all cylinders with the torque plates installed. This and next week include decking the block (the surfaces weren't perfect out of the box), and line honing the mains. At some point I will likely have to buy additional main bearings (I used OEM boss 302 as recommended by Ford Performance) if we end up doing hone work. It was mentioned initially we would have to as some mains had a conical taper to them, but since switching to studs and the torque plates, those measurements have improved.

Boundary switched their oil pump gears design up, I'm going to sell the unused set of gears for this car and get their new finish pump which has a smoother slicker surface. I can't speak to what difference that makes, if any, but Travis at Boundary is excited about it and believes it leads to more consistent pressure and less friction in operation.


Edit: my overuse of commas is a recurring issue.
 
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Double0Fox

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Nice! Sounds like your builder/machinist knows what he is doing. I work in the machining world, and with aluminum we have seen tolerances change by varying the ambient room temperature just a few degrees(small amounts, were talking .0002-.0004) but sometimes it matters. On a side note I built a 2V modular about 7-8 years ago, and had a pretty reputable engine builder in my area tell me torque plates were not needed(Teksid Block)....... proceeded to take my block elsewhere.
 

captdistraction

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Next Update, aluminum chips everywhere!

Once honing was completed, the arduous process of deburring began, every internal surface of the block was visited and cleaned up, removing casting flash, burrs, and rough edges. At the bottom of each cylinder the casting was particularly rough. Some of these pictures are from midway through the process.

20191014_224759027_iOS.jpg 20191014_224801412_iOS.jpg

Additionally all the oiling passages were reviewed, cleaned and ported. The oil feed and return from the oil pad adapter and oil pump pads were cleaned up, flash removed and ported to match the faces that bolt to them.

20191014_212619898_iOS.jpg 20191014_212649592_iOS.jpg

Finally on that front the oil return passages are currently being refined, both on the block and the already-spendy FRPP GT350S oil pan. The bottom of the block was marked on the rails, the windage tray laid on top, and the areas where the block rail covered some of the oil return holes were "ported" back. There's plenty of meat in those areas, so nothing being removed will have a structural impact. This should improve drainback. Same on the pan side, its welded on the external faces but has a sharp edge on the inside that matches the gasket, the edge will get profiled back in places to smooth the transition. The general idea here is to get the oil back in the pickup area as absolutely effectively and quickly as possible. Rough cast edges with sharp points will slow the flow of oil and retain some of it.


Main bearings, revisited:


Before I talked about how there are two methods to set the bearing clearances:
  1. Ford's select fit system: Using bearing grade codes etched into the front of the block and crankshaft and correlate them on a clearance table to select the grade of bearing needed (upper half/lower half).
  2. Actually measure every clearance like a reasonable human being.
To order the parts, I went with option 1, though I did procure some spare bearings in other sizes just in case they were needed.

After assembling the crankshaft to validate a number of items, it was discovered with the selected bearings, the rear #5 position bound up and prevented the crankshaft from turning by hand, using a grade 3 bearing (the tightest of the bunch). To be able to turn the crank, the rear of the bearing had to be sanded down.

It was a bit of a mystery until we realized that in the initial measurements, switching from Ford OEM TTY bolts to ARP studs tightened most of the clearances up slightly. This means that all the bearings I had selected might be too tight for their positions. The other issue is that the bearing table from the service guides aren't the easiest to read (low resolution, and some lack the actual clearance data). I've obtained a nicer version of the charts which has the clearance information so that we can reassemble the block and audit the bearing codes on the crank and block versus actual measurements. We may switch to a different bearing set, one used in nascar currently. I forget the brand but they do have a coyote application, and am prepared that we might have to sand the backsides to hit the target clearances. Thankfully we don't have to do a line hone on the bore, while its being a bit of a pain to get these main clearance targets (25-50 microns, 1/3-1/2 the diameter of a human hair) dialed in, we're able to do it without major machining.

While that's being sorted out the rotating assembly is being balanced. That includes the clutch pressure plate and flywheel up to the damper. Hopefully next week we have the bearings locked down, passages all cleaned up, and a rotating assembly balanced and ready for assembly.




For fun, here's the bearing info from the intial work:

Block build code: MOMLKA3 Crank build code: JMOMND0


1: M J 2/3 upper CU7Z-6D309-B / lower CU7Z-6D309-C (72.412 x 67.492)
2: O M 2/2 both CU7Z-6D309-B (72.414 x 67.493)
3: M O 2/2 both CU7Z-6D309-B (72.412 x 67.495)
4: L M 2/2 both CU7Z-6D309-B (72.411 x 67.493)
5: K N 2/2 both CU7Z-6D309-E (72.410 x 67.494)

Finally, a look at the GT500 valve/coil covers. I want to coat the bare/raw aluminum cast with something, but hadn't come to a conclusion on what as I don't want to insulate it). @ArizonaBOSS votes leaving it raw(dog).

20191014_203921310_iOS.jpg
 

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JAJ

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...I want to coat the bare/raw aluminum cast with something, but hadn't come to a conclusion on what as I don't want to insulate it). @ArizonaBOSS votes leaving it raw(dog).

View attachment 10411
Check around to see if you can find a shop that can anodize and dye them. Doesn't have a material effect on dimensions (coating thickness is about 0.001" or so) but it improves thermal efficiency a lot beyond just bare aluminum if you make it black or a dark color.
 

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