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

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It’s within Detroit tolerance, but the builders and I agree that it’s too far out of spec range for these pistons.

I’ll do some more on this thread soon when I have time to dig in deep. Next up will be the combination selection, classing then I’ll do the block measuring.


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I have a couple of questions about your previous failures, were they valve train related failures and if you don't mind could you give a brief rundown of the probable cause and any steps you have taken to mitigate a future failure.

I have had my share of top end issues with the GenII and think I have the issues sorted, finally. I am also moving to the Aluminator52XS for my next project car I am building and would like to address any issues prior to putting that motor into service.

Anyone here know what the limits of the GT350 oil pan and pickup are, I have always run an aftermarket road race pan on all my motors in the past but several people have advised to keep the GT350 pan setup as there would be little to no gain in making the change to the Moroso or Canton pan over the OEM pan. My gut tells me to bite the bullet and do a drysump on this setup but that really complicates things as far as packaging and budget.

Any input would be appreciated.

Dave
 

Grant 302

basic and well known psychic
I have a couple of questions about your previous failures, were they valve train related failures and if you don't mind could you give a brief rundown of the probable cause and any steps you have taken to mitigate a future failure.

Not to speak for Chris, but you'd need to go through years of threads to get it all. I've been following along through that time and it would be unreasonable or unrealistic to go through it all again to summarize it here. My suggestion is to go through his build thread or go through his post history to find it.

@captdistraction ...forgive me if I am incorrect in my assessment!
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
concur. @ddozier I'll PM you with some thoughts, but most of my failures have been related to the builds themselves. 1 Tuning related failure (oem), 3 builder related failures (MMR), 1 questionable failure (FRPP), and then one motor that made it through :). I'll cover the oil pan stuff here in a post. I'm way overdue for two of the updates, I'm authoring them now (Build Parts Selection and Engine block measurements).
 
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39
[QUOTE="

I have had my share of top end issues with the GenII and think I have the issues sorted, finally. I am also moving to the Aluminator52XS for my next project car I am building and would like to address any issues prior to putting that motor into service.

Anyone here know what the limits of the GT350 oil pan and pickup are, I have always run an aftermarket road race pan on all my motors in the past but several people have advised to keep the GT350 pan setup as there would be little to no gain in making the change to the Moroso or Canton pan over the OEM pan. My gut tells me to bite the bullet and do a drysump on this setup but that really complicates things as far as packaging and budget.

Any input would be appreciated.

Dave[/QUOTE]


I have been running the GT350 oil Pan without any issues for over two seasons..Rd Course hotlaps on Level tracks like LVMS Outer to Banked tracks at PPIR. I autoX, and Speedstop it while hitting 8200 rev limit in 1st and 2nd gear. Pan and windage tray weighs only 7.5 pounds.
My 5.2 Voodoo with CPC makes 530 SAE whp and has lots of torque down low...400+ wheel torque at 3100 rpm to 6900rpm. Has 29K miles on it with at least 1/3 being on track. 93 tune and E85 for track use. Still going strong but I am starting to build Build another one with improved heads work, upgrade valve springs and aftermarket pistons and rods this time. trying for 13:1...and 575 whp and still very durable and reliable on track and street.
 
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Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Just to make sure? The Boss forged Crankshaft is part number M-6303-M50B? or FR3Z-6303-C? Or are they the same?? they have a 100 buck price difference for some reason......
 

Grant 302

basic and well known psychic
FR3Z-6303-C seems to be the updated part also listed for the newer Gen2 engines.
M-6303-M50B sounds like the original Boss part number and does not appear to have a 'C' coded update.

$208 on sale at tasca:
https://www.tascaparts.com/oem-parts/ford-crankshaft-fr3z6303c

I'd use the newer part for anything but a 'numbers matching' build. Especially for the cost savings. Newer cranks seem to be fine.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
CaptBlownMotors here:

Having gone through every type of motor you can put in a road race car (Factory, Custom shop built, Ford Performance) and had lots of trouble over the years, I thought it would be a good exercise to walk through blueprinting and properly building up a motor for road racing.

After blowing up a motor spectacularly in early 2018 (and still inexplicably - to me at least), I bought a used 2011 motor from @steveespo to keep me racing through the season. That turned out to be the right call as the car made every single race after that without issue! It wasn't quite as powerful as the motor replaced, but the reliability paid off big in the end.

Now that the dust has settled, I'm building a motor to meet the Super Touring 2 classing limits and bring the car a bit closer to the competition (which is faster mustangs, a GTR, corvettes, oh my). I've partnered with a local shop to do the work (operated by someone who has built for almost every racing series that needs gasoline engines to compete). Their experience and attention to detail had sold me, as I had used them to measure out all my old equipment from the aluminator I had broken in February.

After cleaning up and going through the parts, we made the determination that only two parts could be used from the old engine for anything new: the Manley H beam rods (after cleanup work, they're not perfectly round even when brand new), and the oil-squirter blockoff plates.

Given that, I turned to my sources for Ford Service and Ford Performance Parts and ordered the following:

View attachment 6080

Some of this stuff ended up being unused like the head bolts (replaced by the head stud kit as we needed to install, then reinstall heads or cylinder torque plates a few times for blueprinting and machining operations). Same with oil pan bolts, main bolts from the hardware kit (and the bolts that come with the block, etc).

More to come.


Hate to bug you on this thread which has to be stalled.... But how do you know which main bearing letter to get???

upload_2019-2-10_19-12-27.png
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
I’ll go into detail but you pick based on one of two ways:

There’s a bearing code written in the crank and block and a table you can use to select the grade bearing

Or

For used parts you can pick the target clearance based on parts measurements and the bearing table will give you the target clearance


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Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Thanks! Would I be ok with a set of Clevit bearings CLE-MS2292H ?? The crank was STD.... My screwup has the builders with my parts in the clean room but no main bearings... But they can start with the heads in the mean time..

Summit can fedex the clevit setup to me by wed..
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
I know you are in limbo with your motor, but wanted to say that your parts list at the begining of this thread is very useful. I did see that CR3Z-6211-A is the number I get for the conrod bearings instead of the one in your list (4G7V-6211-AA). When I enter that number it says its for the V6?
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
I know you are in limbo with your motor, but wanted to say that your parts list at the begining of this thread is very useful. I did see that CR3Z-6211-A is the number I get for the conrod bearings instead of the one in your list (4G7V-6211-AA). When I enter that number it says its for the V6?

The rod bearing size is common among a few ford motors. This is actually the bearing used in the GT500 trinity motor (which ford performance used in the aluminator 5.2xs)

That said I might be short 8 halves. I need to check tonight. I am still hunting someone to take over my project but I can start producing content again about the build soon.


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captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
Drama now mostly aside, I wanted to post an update (also will link out in the first post to keep this easy):

UPDATE 1: Combination Selection

Most of it was covered in the first post (there's additional hardware like miscellaneous bolts, harnesses, and some additional ARP fasteners like oil pan and cam cap kits), but the overall idea was to shoot for 475 RWHP for use in ST2 class and keep it reliable. My experiences so far with the coyote platform point to two major Achilles's heels: build quality and clearance/tolerance control, and oiling. The coyote platform is making absurd numbers for its size along with RPM and the more you ask of these motors the higher requirement for perfection in the build and supporting hardware.

To that effect I selected these core components:

Gen 2 Ford 5.0L bare block: Nothing fancy, but selected due to affordable cost and the pressed-in iron liners seem to have less reports of oil consumption than their newer fancier spray-bore brethren. The 5.2L options are tempting, but again the ratio of builds running into consumption or shorter lifespans scared me off. There's a few things to note about the Gen 2 5.0Ls:

  • There's a need to do a lot of deburring and cleanup of the oil inlet
  • speaking of oil inlet, there's a different oil filter mount (than gen 1 or gen 3), important to match this up
  • Machine work - advertised as finish honed, ready to assemble. (its not, not even close if this is a build for racing purposes)
  • It did include some hardware like the main bolts and side bolts, they're really for shipping only, as the engine was machined with them installed (and they're TTY). You do need a block parts kit (seen in my list in post 1)
  • ARP studs do measure out differently than when using stock TTY bolts. I've not been a big believer before of the better hardware making a meaningful difference, but it does tighten up tolerances when properly torqued. Also nice to use one set of hardware versus 5 sets for building (since you need to discard after torquing).
Boss 302 Cylinder Heads: Different aluminum, ported from the factory, uses standard 5.0L drivetrain components. Lightweight stainless valves, with exhaust valves being sodium filled. Worth a number of HP over the base Gen1 head, clearanced for larger camshaft profiles. Not much else to report here other than difficult to find (though FRPP does have a recently "discovered" inventory of them)

L&M Intake Camshaft and Boss 302 Exhaust Camshaft (production): These parts were selected as the intake cams can be worth 20HP on an otherwise stock-ish build, but without significantly moving the RPM band up. The exhaust cam is also critical in helping to maintain low end torque. Other larger options will give up torque in exchange for up top horsepower. I wanted a balanced approach that left me torque to get the car off the corner, but additional power in a "constantly rising" power band that plays well with the current NASA Super Touring rule set (they favor more triangular power bands due to averaging hp over a number of RPM points).

Mahle "Gen 3" forged powerpak piston:
These things are beauties. Revised pockets for the new GT350 heads (and other larger valve setups), multiple coatings for slickness and hardening. Stuck with a 11.25-11.5:1 piston (final compression based on measurements of the finished components. This should play nice with 100 octane fuel and tuning from AED.

Manley "commodity" forged H beam rods:
I had a set from an aluminator measured, the small ends needed just a bit of honing to be perfect, then the large ends were dead-on perfect. These rods have been used for many years in the aluminator, and many of the high HP oem builds.

OEM 14 GT500 rod and Boss 302 main bearings:
Sticking with the oem bearings after discussing at length with race teams and FRPP staff. The GT500 rod bearing is the same size and is a heavier duty bearing than what the coyotes initially used.

Cobra jet intake and mono-blade throttle body:
off the shelf for me, still a great performer from 3500-8250.

"Kooks" long tube headers.
Shorter than most long tubes, but proven to make excellent power with good scavenging.

FRPP parts for timing:
Gen1 complete timing kit (as all controlled with a gen1 ecu), Service forged crankshaft (gen2), Upgraded lash adjusters (GT350R/Voodoo). I am mulling the PAC-1234x valve spring and retainer package to further help durability

Oil Pan: The new FP350S pan, with a Boundary blueprinted oil pump assembly and matching pickup tube. This isn't finalized yet as I may move to a GT350 housing and pickup to improve aeration resistance. I've used Moroso pans to great success and have no reason to believe they're holding me back, but for the cost of this build I wanted to match what has been dropped in the 302 S/R and 350S/GT4 as much as my budget would allow.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Just wondering if a GT350 or GenIII head would be a valid option?
 

Attachments

  • upload_2019-2-21_15-36-15.png
    upload_2019-2-21_15-36-15.png
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captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
Update 2: Measuring, measuring and measuring. No machine, just measure.

Outside part selection the biggest contributor to success is blueprinting. Blueprinting a motor means to measure out every critical tolerance, record that data, and use it to make informed decisions on machining and other assembly operations. Also recording the final results which ensures both accuracy of the work, optimizing the efficiency and performance of the motor, and also gives you a known value for wear tracking. I can't understate how important this is, having owned a large number of coyote and voodoo motors that all had varying levels of quality behind them.

Built Ford Proud
: Why go through this process? Shouldn't the OEM with all its fancy machines be able to build something much better than the average backwoods machinist? Yes and no. Ford's production is based on cost, reliability and efficiency in mass manufacturing. Not racing, thus the tolerances on a production OEM long block are much wider in range than one would want on a racing-specific build. The blocks are not machined with a torque plate (more on this shortly), varying piston-to-wall clearances, and bearing selection has been boiled down to an automated process to meet their requirements without the need to hand-measure every assembly. Rotating assemblies are "built to balance" versus actually balanced, where known median values for parts weights are used.

Ford Performance builds the aluminator line of engines, which are a little more race oriented. They take assembled long and short blocks fresh from Ford's engine plants, tear them down and insert hardened parts to improve power and reliability in high performance applications. There's some variance in how each motor part number is built, but the summary is there's still things like "built to balance" and bearing code use happening at this level. Tolerances are tightened and published in documentation given with the block, but this is not to be confused with blueprinting which is a costly process outside their core target consumer.

I've dropped off all these boxes to the machinist, what next?:

Everything is laid out and inspected, cleaned and then measured.

for measuring the pistons, block, rods and crank the assembly is set out to equalize temperature of all the components in a clean room. Once the parts have sat for several hours, the parts can be measured with confidence that temperature will not cause variation at the precision level (often into the thousandths of ten-thousandths of an inch.)

Those are all recorded. In my case it revealed some interesting things:

P2W: The target piston to wall clearance from Mahle was: 0.0006" to 0.0014" which is considered fairly tight (however, their use of a 4032 alloy means this tight tolerance results in a more quiet engine in operation, less piston slap or noise when colder, and expansion is minimized). This tolerance is similar to the FRPP/Aluminator (since they use a white-labeled part number of a similar piston from Mahle). Ford calls for .0009-.0023" for the OEM clearance, which is much wider.

Here's an example of how the block measured out for that target clearance:
upload_2019-2-21_12-8-21.png

No bueno, without heads or torque plates, the cylinders were perfectly round, which means that they were machined without torque plates. Why is that important? A torque plate simulates the torquing loads of the cylinder head, and as the bolts go through the block they distort the cylinder walls. Its important to make sure the block is measured with plates or heads bolted on as this is the environment as the pistons will live in. Even above, this block would technically fail for an oem piston's range, especially near the top of the cylinder which gets the most distortion towards an oval shape.

Crankshaft/Main bore:

Similar story, the mains can be clearanced the ford-way, which involves reading a printed bearing code from the crankshaft and face of the block, looking at a table to get the bearing "grade"; or the old school and blueprinted way of measuring the actual clearances to get the target bearings.

In my case we again ran into trouble, looks like the honing machine ford used made some incomplete passes towards the end and had tapering in the main caps. This will have to be corrected with a line-honing operation. Interestingly enough, the taper was visible due to the etching pattern seen on the faces of the mains.


upload_2019-2-21_12-15-42.png

Also, interesting to note here the difference between arp studs, and stock bolts. The positions in the colored bars are upright, 90* to upright, then 45* to upright. F in the column below is front facing towards the front of the car and R towards the transmission for each main bearing location.

The rods were also measured, and a light cleanup hone was done to bring them into spec on the small ends. Everything else measured out correctly.

The next update involves the machining processes and deburring. I'll start adding pictures as well soon. Unfortunately, the build is slated to start April 1, so some patience but I'll update as I can.
 
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Update 2: Measuring, measuring and measuring. No machine, just measure.

Outside part selection the biggest contributor to success is blueprinting. Blueprinting a motor means to measure out every critical tolerance, record that data, and use it to make informed decisions on machining and other assembly operations. Also recording the final results which ensures both accuracy of the work, optimizing the efficiency and performance of the motor, and also gives you a known value for wear tracking. I can't understate how important this is, having owned a large number of coyote and voodoo motors that all had varying levels of quality behind them.

Built Ford Proud
: Why go through this process? Shouldn't the OEM with all its fancy machines be able to build something much better than the average backwoods machinist? Yes and no. Ford's production is based on cost, reliability and efficiency in mass manufacturing. Not racing, thus the tolerances on a production OEM long block are much wider in range than one would want on a racing-specific build. The blocks are not machined with a torque plate (more on this shortly), varying piston-to-wall clearances, and bearing selection has been boiled down to an automated process to meet their requirements without the need to hand-measure every assembly. Rotating assemblies are "built to balance" versus actually balanced, where known median values for parts weights are used.

Ford Performance builds the aluminator line of engines, which are a little more race oriented. They take assembled long and short blocks fresh from Ford's engine plants, tear them down and insert hardened parts to improve power and reliability in high performance applications. There's some variance in how each motor part number is built, but the summary is there's still things like "built to balance" and bearing code use happening at this level. Tolerances are tightened and published in documentation given with the block, but this is not to be confused with blueprinting which is a costly process outside their core target consumer.

I've dropped off all these boxes to the machinist, what next?:

Everything is laid out and inspected, cleaned and then measured.

for measuring the pistons, block, rods and crank the assembly is set out to equalize temperature of all the components in a clean room. Once the parts have sat for several hours, the parts can be measured with confidence that temperature will not cause variation at the precision level (often into the thousandths of ten-thousandths of an inch.)

Those are all recorded. In my case it revealed some interesting things:

P2W: The target piston to wall clearance from Mahle was: 0.0006" to 0.0014" which is considered fairly tight (however, their use of a 4032 alloy means this tight tolerance results in a more quiet engine in operation, less piston slap or noise when colder, and expansion is minimized). This tolerance is similar to the FRPP/Aluminator (since they use a white-labeled part number of a similar piston from Mahle). Ford calls for .0009-.0023" for the OEM clearance, which is much wider.

Here's an example of how the block measured out for that target clearance:
View attachment 7039

No bueno, without heads or torque plates, the cylinders were perfectly round, which means that they were machined without torque plates. Why is that important? A torque plate simulates the torquing loads of the cylinder head, and as the bolts go through the block they distort the cylinder walls. Its important to make sure the block is measured with plates or heads bolted on as this is the environment as the pistons will live in. Even above, this block would technically fail for an oem piston's range, especially near the top of the cylinder which gets the most distortion towards an oval shape.

Crankshaft/Main bore:

Similar story, the mains can be clearanced the ford-way, which involves reading a printed bearing code from the crankshaft and face of the block, looking at a table to get the bearing "grade"; or the old school and blueprinted way of measuring the actual clearances to get the target bearings.

In my case we again ran into trouble, looks like the honing machine ford used made some incomplete passes towards the end and had tapering in the main caps. This will have to be corrected with a line-honing operation. Interestingly enough, the taper was visible due to the etching pattern seen on the faces of the mains.


View attachment 7040

Also, interesting to note here the difference between arp studs, and stock bolts. The positions in the colored bars are upright, 90* to upright, then 45* to upright. F in the column below is front facing towards the front of the car and R towards the transmission for each main bearing location.

The rods were also measured, and a light cleanup hone was done to bring them into spec on the small ends. Everything else measured out correctly.

The next update involves the machining processes and deburring. I'll start adding pictures as well soon. Unfortunately, the build is slated to start April 1, so some patience but I'll update as I can.


Nicely done. I need to get my measurements in a speadsheet. I'm waiting on a straightedge so I can check the line bore of the mains. Got a blade tip micrometer coming too but the pistons are not even ordered yet. Finalizing them tomorrow hopefully.

I really believe the 5.2 blocks are machined with tighter tolerances than the Coyotes blocks. I have not build the coyote engine though several 4.6 engines and my 5.4 for my Expedition but never opened my 2011 Coyote engine.

By the way I used all OEM bearings in my current motor and they have held up well but the rod bearings will rotate in the rod bores on the 5.2 engines due to not having any tangs. I never did understand the reason for no tangs. Also only used factory bolts. I prepped the engine with one set and used a new set for the final assembly. I have been able to torque them several times and try to limit the last turning to 90* to limit the yielding of the bolts so I reuse them several times during prep. With a digital torque wrench you can tell when the bolt is in yield as it turns but doesn't increase the torque reading. May not be 100% proper but it has worked for me so far. I do have ARP mains bolts for the new engine though. Still debating on the ARP head bolts due to the huge difference in the thread length of OEM bolts and the short ARP threads. I know the ARPs have enough threads for torque loads but I am concerned about different location of the threads on the bolt hole...pretty sure it will affect the cylinder diameters differently. I could tell on the bore gauge where the holes where full of threads and where they stopped as the cylinders were much closer to maintain roundness in the lower portion of the cylinders. At least that is what I have surmised.
 
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