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

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captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
I'd absolutely make sure you have the right hardware. Also, I'd be concerned that not yielding the bolts might result in a slightly different reading than going all in TTY. They're fairly cheap bolts, I'd buy a few sets if it were me (I did buy 5 sets for this build before going to studs and selling off the spare unused sets). I wonder if ARP has anything for that application or could build you something.
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
While I wait on the shortblock assembly (which is finally underway), I've made a couple changes to the lineup. A set of JPC billet chain guides for the tensioned sides of the primary timing chain, a set of Super Heavy Duty secondary chains from Sai Li, and a set of PAC titanium retainers were spec'ed out. Ultimately concerns about the 1234x valvespring drove a few upgrades to support the additional forces found in the valve train. The only remaining concerns I can possibly see are the gen1 VCT phasers not being able to deal with the increased pressures and resetting to zero advance, and possibly the valve stems not being up to the base pressures (though I'm less worried about this, the one case I've seen was a turbo car with a massive increase in cylinder pressures and temperatures).
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
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.

Valvesprings-10a.jpg

Final Note on selection: Titanium is a high wear rate material in this application. Yearly replacement is recommended per Ford on the FP350S. I'm going to see if I can push that to two years, but its not a huge cost. The springs would be checked at the same time and would be replaced if they fall significantly under their spec. Usually boss springs are a yearly or bi-yearly replacement item (though I've never made anything last a year personally), but this may allow longer intervals.

Spring Replacement:

The process is pretty straight forward, but time consuming. The tools needed are a valvespring compressor (I borrowed one from @ArizonaBOSS ), a 14mm socket, 3/8" long hex drive socket, a magnetic pickup tool, 8mm socket (for cap bolts), and paint pens for marking.

The process (for head on a bench) is:

  1. label / validate cam caps and remove them from the head
  2. Install the tool base and arms over a set of valves to be removed
  3. Tighten down the main bolt on the tool to compress the spring and expose the keepers
  4. using the magnetic pickup tool makes it easy to grab the keepers
  5. undo the compressor bolt to release the valvesprings and retainers. Remove the assemblies
  6. install in the new springs and retainers
  7. Compress them using the compressor tool (this was difficult with the exhaust side, as the bolt was too short to start without hand compressing the assembly)
  8. With the springs compressed, carefully replace the keepers back on the valve stems (the pickup tool was used plenty to get dropped keepers out of the head). Also the valves are free to drop down, so be sure to seat them, I used a paper towel folded up under the head to hold them up in the chamber bowls.
  9. slowly undo the compressor tool and watch the retainer capture the keepers
  10. Take final measurements, and mark the completed assembly with a paint pen (I also measured the tops of the valves to ensure all keepers were properly seated as I marked each one).
Both heads took me about 4 hours altogether. On car it would be even longer, removing the cams and ensuring to put each cylinder to TDC and pressurizing them with air to hold the valves up. My biggest tips are go slow, measure everything carefully.

I also took the time to install the arp cam cap bolts. I see a lot of value in these as the caps require careful torquing to properly retain the cam and maintain its clearances. Additionally the arp kit is reusable where the oem bolts are TTY / one use only.

Some Photos of the process:
Valvesprings-2.jpg

Valvesprings-4.jpg

Valvesprings-5.jpg

Valvesprings-6.jpg

Valvesprings-9.jpg

Valvesprings-18.jpg

Valvesprings-22.jpg

Valvesprings-32.jpg

Valvesprings-33.jpg

Valvesprings-36.jpg

Valvesprings-39.jpg



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.

Valvesprings-41.jpg
 
741
1,075
TX
Looking good, Chris. Looks like you're putting together a hell of a machine!

Couple of questions for ya'
  1. How do you plan to evaluate the life of the springs in a year? Is there something you actually measuring to see if hte springs/retainers to be replaced?
  2. Have you/do you plan to change routing for the coolant ports on the heads? When I rebuilt my motor, I deleted the part that went into heater core and looped the two hoses together behind the engine. It's working so far, but looking for better ideas.
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
Looking good, Chris. Looks like you're putting together a hell of a machine!

Couple of questions for ya'
  1. How do you plan to evaluate the life of the springs in a year? Is there something you actually measuring to see if hte springs/retainers to be replaced?
  2. Have you/do you plan to change routing for the coolant ports on the heads? When I rebuilt my motor, I deleted the part that went into heater core and looped the two hoses together behind the engine. It's working so far, but looking for better ideas.

Only way to check the springs is pull them after a period of time and check them with a spring checker. The retainer is visual inspection. If I get the car running by summer I’ll check them at the first interval of January 2021 (when the car is 10 years old, yikes)

For the coolant ports I did what you are talking about with tying them behind the intake with a rescrictor. This time I’m using two quick disconnect ends and tying them underneath the throttle body with a much shorter hose. I’ll post up in my other thread what parts and how the assembly looks. With the GT350 intake I’ll see if that works for yours as well (since I so happen to have a 350 nearby)



Sent from my iPhone using Tapatalk
 
6,360
8,180
FWIW the Roush engines in IMSA were rated for 50 hours, I think the Porsche stuff was as well, I'm going to assume it was because of the valve springs.
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
FWIW the Roush engines in IMSA were rated for 50 hours, I think the Porsche stuff was as well, I'm going to assume it was because of the valve springs.

God Id love to hit 50 hours on a motor.


Sent from my iPhone using Tapatalk
 
For the coolant ports I did what you are talking about with tying them behind the intake with a rescrictor. This time I’m using two quick disconnect ends and tying them underneath the throttle body with a much shorter hose. I’ll post up in my other thread what parts and how the assembly looks. With the GT350 intake I’ll see if that works for yours as well (since I so happen to have a 350 nearby)
Sent from my iPhone using Tapatalk
I have mine cross over the throttle body, GT350 intake/TB no restrictor. I've cut off the nipple for the vapor hose and plugged with a bolt. Stock Ford connectors.
20190430_152055.jpg
 
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741
1,075
TX
I have mine cross over the throttle body, GT350 intake/TB no restrictor. I've cut off the nipple for the vapor hose and plugged with a bolt. Stock Ford connectors.
View attachment 7861

I was using the OEM connectors and had one fly off on the Dyno. Shot coolant about 15ft in the air. At least my barbed coupler didn't fail. Haha
 
I am not sure they make them for the Coyote but if you are trying to get 2+ years out of the retainers I would see if the tool steel retainers from Ferrea are available. I looked on their website but it is so far out of date I think the only way to get any valid info would be to call them. Their tool steel retainers are machined not stamped and are made the same as their Titanium retainers just made from tool steel, since the material is stronger they can be machined thinner and as a result come in at nearly the exact same weight but should be more durable. They will have a better service life than titanium if they are available.

Dave
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
No tool steel retainers available for a stock style spring that I could find at this time. There are some packages out there with aftermarket valves, locks, springs and seats, but I didn't want to explore that. We'll see how they wear and I am keeping the oem retainers around as well as backups (not expecting a failure, just if the wear rate is very accelerated)
 
741
1,075
TX
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

Hey Chris -

What's the latest on the oil galley stuff?
 
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captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
Nothing. I'm 50/50 on whether I want to pioneer in this area or leave it alone. the rest of this build is all about going with known quantities (outside the valvespring which is "mostly known"), so I'm not sure how much I want to deviate.

That said, I'll keep following up on it. Hopefully once I have the motor as an assembly I can look at what it would take to make some hard lines.

If I were to explore it, here's the bill of materials:
4x AT165206ERL - 3/8 npt to 3/8 hose compression fittings
1x ZZ661625ERL - 3/8 steel coated hose
1x Pittsburg 3755 - (yes, hazard frought) tubing bender
1x tubing cutter of your choice (that can cut steel). About $110 altogether
 
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