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Motor upgrading questions.

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Hello everyone! I have a few questions about upgrading my motor. I am running a 2012 5.0 in my GT and I would like to get to the 7500RPM range safely. other then using a boss 302 intake, Oil pump gears and Crank sprocket what other parts would be needed or you would suggest? also where would you suggest to get a tune for the intake and other modifications. all that's done to my motor is a Airraid intake at this time. car is manly used for street driving and Autocrossing.
 
I've also canvassed the Internet for information related to this. It seems to be mostly passed-down information from Ford, but I can't guarantee any of it is accurate. From what I can tell, here is the estimated overhead from Ford when they instilled the stock 6,800 redline:

GT con-rods and bolts good to 7,400 (the connecting rod bolts undergo a lot of force at the top of the exhaust stroke when there is no compression and the piston has to change direction)
Pistons good to 7,300
Oil squirters may starve top end past 7,500
Stock pulse ring good to 7,700
I'm unsure at which point the stock valvetrain goes unstable, but it's been mentioned that the Boss springs are good to 7,900.

I'd love it if others had more information, since most of this is just passed-down 4th generation forum-babble at this point, though it does sound in line with Ford's usual 500-rpm-over safety margin. You'll find plenty of people who say 'screw it' and rev the thing to 8k, but I don't think any of those last (though I would love it if that was the case).
 
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I've also canvassed the Internet for information related to this. It seems to be mostly passed-down information from Ford, but I can't guarantee any of it is accurate. From what I can tell, here is the estimated overhead from Ford when they instilled the stock 6,800 redline:

GT con-rods and bolts good to 7,400 (the connecting rod bolts undergo a lot of force at the top of the exhaust stroke when there is no compression and the piston has to change direction)
Pistons good to 7,300
Oil squirters may starve top end past 7,500
Stock pulse ring good to 7,700
I'm unsure at which point the stock valvetrain goes unstable, but it's been mentioned that the Boss springs are good to 7,900.

I'd love it if others had more information, since most of this is just passed-down 4th generation forum-babble at this point, though it does sound in line with Ford's usual 500-rpm-over safety margin. You'll find plenty of people who say 'screw it' and rev the thing to 8k, but I don't think any of those last (though I would love it if that was the case).


so unless I address the lower engine I should only stick to about 7,000-7200 max. with that being said i still want to install my boss 302 intake and long tube headers. where would be the best place to have get it tuned for this? would I benefit from having a local tuning shop do it or get one from LMR/American muscle.
 
so unless I address the lower engine I should only stick to about 7,000-7200 max. with that being said i still want to install my boss 302 intake and long tube headers. where would be the best place to have get it tuned for this? would I benefit from having a local tuning shop do it or get one from LMR/American muscle.
I'd suggest sticking with the stock limiter, around 6800-7000, if you like your engine and don't plan to do a rebuild. If you do a performance rebuild, specifically including new connecting rods and ARP 2000 conrod bolts, you may be able to get away with more. The stock Mahle hypereutectic pistons use the oil squirters to keep the chance of detonation lower than if without, whereas the Boss connecting rods and pistons are different and don't need the oil squirters to stay alive. The Boss also uses ARP 2000 connecting rod bolts, to my knowledge. I did some further digging and a quote from Todd Brewer, one of the people on the cylinder head design team, said that the stock valvetrain was capable of redline 'plus several hundred rpm more', which I would interpret to say is around 7,300-7,400 to be in line with the rest of the overhead. I'd suggest swapping in Boss valve springs if you do a bottom end build (M-6513-M50BR x2) and still want to retain the street driving characteristics. The Boss springs are slightly stiffer for RPM tolerance, but aren't a high enough rate to impact VCT actuation (if you run too stiff a valvespring, the VCT may not be able to function correctly).

Stock Coyote Valvespring Rates
Closed: 265 N – Open: 650 N
Boss 302 Valvespring Rates (installed height is same as stock, 40mm)
Closed: 300 N – Open: 700 N

As far as all of this, I would suggest talking with a Coyote builder in your area and mention what your end goals are. Same with tuning, I would suggest talking to a local tuner that knows Coyotes and can do an in-depth tune rather than do a canned tune you would get from the common aftermarket digital storefronts like AM. I've seen some good things mentioned about remote tunes if you don't have a tuner in your area, but I haven't personally done it.
 
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1,104
1,704
Exp. Type
W2W Racing
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3-5 Years
Huntsville, AL
I cant offer any help relative to your question, as I am completely in left field relative to the newer engines. However, where does the overall package stop making power? For instance, where does the cam level out? In my mind, there is no reason to spin the engine any higher than that RPM as you are placing undue stress on the components for absolutely no return or gain. Again, I'm asking because I do not know.

Kind Regards,
Patrick Stapler
 

CCapaldi

Supporting Vendor
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46
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10-20 Years
Michigan
well thanks for the info! no sure what I will do for a tune, closest mustang tuner is 200 miles away lol

Where are you located? We are in Macomb County, we may be able to offer some input.

As for the motor upgrades, alot of the basics have been touched on above from and internal side that would help ensure longevity of the engine at higher rpms. A few things I would take into consideration (based upon autocrossing).

Baseline HP and TQ curve with current setup and use a simple spreadsheet to input trans ratios / tire circumference / final drive ratio. At this point you can mathematically determine max speed/rpm each gear as well as the rpm dropout on an upshift. With this information you can see if you can keep the car in optimum power band on a particular course. Alot of times we have found spinning the extra rpm isn't "always" the best solution, but rather a rear gear change to take advantage of the given power band.

In the same token, there are occasions where the extra rpm may not put you in optimal power band but will save time on up shifts and down shifts....just something to consider.

Feel free to reach out about engine upgrades or input in general if you have any questions.
 
Where are you located? We are in Macomb County, we may be able to offer some input.

As for the motor upgrades, alot of the basics have been touched on above from and internal side that would help ensure longevity of the engine at higher rpms. A few things I would take into consideration (based upon autocrossing).

Baseline HP and TQ curve with current setup and use a simple spreadsheet to input trans ratios / tire circumference / final drive ratio. At this point you can mathematically determine max speed/rpm each gear as well as the rpm dropout on an upshift. With this information you can see if you can keep the car in optimum power band on a particular course. Alot of times we have found spinning the extra rpm isn't "always" the best solution, but rather a rear gear change to take advantage of the given power band.

In the same token, there are occasions where the extra rpm may not put you in optimal power band but will save time on up shifts and down shifts....just something to consider.

Feel free to reach out about engine upgrades or input in general if you have any questions.

I am live in Higgins lake up in Roscommon county so its more around 150/175 miles but I can trailer it down to the Detroit area if I have to, but not being from that area I have no clue on who to take it to or trust. as for the motor building question I was under the impression that it was basic things I needed to worry about to bump up the redline, like the oil pump gears, crank gear, intake, and timing chain guides and tensioners. not realizing that I need to address bottom end and head issues.

As far as performance on the track I have the problem with toping out second gear at the end of straits. the car has 3.73's which when I bought it I though it had 3.31 (someone had to of changed this). Now with finding all of this information and going back over what is needed and my goal for the car to be a fun street/track car I'm not even sure if its worth doing the boss 302 intake. I want to do long tube headers though! with no plan on boost so I am going to go with the LTH 1 3/4 headers so I can use my boss H-pipe and side pipes.
 

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