13/14 VS 11/12

2011 gtcs

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So I feel like I'm missing something, why do I keep hearing the 13/14s are basically tapped out stock compared to the 11/12s and they aren't as mod friendly as the 11/12s. Both my 13 and my 14 GT500s have responded extremely well to mods, as have most of your guys GT500s. Why do people keep saying this? What am I missing.
 

jazz

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I’ve heard some people say the samething, 5.8 should be more mod friendly... however stock 07-12 is rated for 550hp @9lbs of boost. 13/14 makes 662hp @15lbs... Doesnt make sense and 13/14 rev higher too.
 

MG0h3

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Geez I didn't know there was such a disparity in boost. What does the 11/12 make on 14psi? Most pick up around 20rwhp per psi so it should be close.

I'm not real educated on the GT500s but I am aware of the "weaker" rods in the 13/14 and incredibly expensive blocks. Maybe that's part of it?
 

reeve_ryan

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Possibly that the 13+ got a bump in CR and doesn’t like added timing on pump gas? The rods from 07-14 are all the same I believe. A trinity blower on a 5.4 vs 5.8 with same mods should be within 20hp of each other.
 

2011 gtcs

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I’ve heard some people say the samething, 5.8 should be more mod friendly... however stock 07-12 is rated for 550hp @9lbs of boost. 13/14 makes 662hp @15lbs... Doesnt make sense and 13/14 rev higher too.
I know once you start modding the 13/14s you should only rev them to 6k, but with $1,500 in mods on a 13/14 and you're almost 700whp. It cost a lot more to get a 11/12 to that level.
 

Eatonualive281

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The cylinder liners are very thin in a 5.8 block. Not alot of sealing between the piston bores etc. Id personally take an 11-12 block with a standard bore over a trinity block any day.
 

2011 gtcs

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Geez I didn't know there was such a disparity in boost. What does the 11/12 make on 14psi? Most pick up around 20rwhp per psi so it should be close.

I'm not real educated on the GT500s but I am aware of the "weaker" rods in the 13/14 and incredibly expensive blocks. Maybe that's part of it?
The 11 to 14 GT500s all have the same rods, idk who started saying they were weaker or different. The 13/14s have factory Manley pistons and pistons squirters and a CJ crank.
Possibly that the 13+ got a bump in CR and doesn’t like added timing on pump gas? The rods from 07-14 are all the same I believe. A trinity blower on a 5.4 vs 5.8 with same mods should be within 20hp of each other.
With the extra compression I do think you need to be a little more conservative with timing, I run a MS100 just to be safe at my power level.
 

2011 gtcs

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The cylinder liners are very thin in a 5.8 block. Not alot of sealing between the piston bores etc. Id personally take an 11-12 block with a standard bore over a trinity block any day.
This is true. But it hasn't seem to be a big issue.
 

Eatonualive281

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Well when you start to push past 750whp it seems to be. But id still rather take the block with more material because lets face it, once you slap a bigger blower on, id take the stronger block.
 

MG0h3

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The 11 to 14 GT500s all have the same rods, idk who started saying they were weaker or different. The 13/14s have factory Manley pistons and pistons squirters and a CJ crank.

With the extra compression I do think you need to be a little more conservative with timing, I run a MS100 just to be safe at my power level.

Ya wasn't aware of that on the rods. Does the 5.8 get to the breaking point easier maybe so that limit has been tested more?

Guess I've just seen a handful of comments about "too much power" on the stock block RE a 5.8 but not so much for a 5.4.
 

2011 gtcs

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Ya wasn't aware of that on the rods. Does the 5.8 get to the breaking point easier maybe so that limit has been tested more?

Guess I've just seen a handful of comments about "too much power" on the stock block RE a 5.8 but not so much for a 5.4.
I think one of the issues with 5.8 is people shift them way too high when they start making big power. The 5.4s redline is 6k so most don't go higher than that.
 

2011 gtcs

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Well when you start to push past 750whp it seems to be. But id still rather take the block with more material because lets face it, once you slap a bigger blower on, id take the stronger block.
Oh I agree, and if you do want to keep using the 5.8 than it's a good idea to sleeve the block
 

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They do not have the same rods.

The 13/14 rod is tapered at the top of the small end to fit the new pistons, theoretically making it weaker than 07-12 rods. Measurably weaker? No, probably not.

Trinity block has maxed out bores as mentioned earlier and is insanely expensive to replace.

It is pretty widely agreed that a safe rpm limit for any stock block 07-14 motor is 6500 rpm.
 

2011 gtcs

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They do not have the same rods.

The 13/14 rod is tapered at the top of the small end to fit the new pistons, theoretically making it weaker than 07-12 rods. Measurably weaker? No, probably not.

Trinity block has maxed out bores as mentioned earlier and is insanely expensive to replace.

It is pretty widely agreed that a safe rpm limit for any stock block 07-14 motor is 6500 rpm.
This is right out of the article from mustang360 about the rods, 2013 Ford Shelby GT500 Trinity 5.8L V8 - Power Of Three - 5.0 Mustang & Super Fords Magazine

"The new piston is supplied by Mahle. While a conventional design, it does feature thick bulkheads to better support the piston dome. The angled geometry of these bulkheads is such that the small end of the connecting rod would no longer fit, so the small end of the rod was ground off at an angle, with the top of the small end narrower than the bottom of the piston-pin bore in the rod. Of course, if you change one thing you change another, and narrowing the small end of the rod closed the edge distance from the piston pin oiling hole in the top of the rod so much that Brendan Vido's computer modeling showed the rod became weak. Luckily the oil squirters put so much oil onto the bottom of the piston that there's no need for the oil hole in the 5.8, so the hole was deleted and rod strength preserved. Otherwise, the 5.8 connecting rod is unchanged from its 5.4 starting point."

So yes they did narrow the rods, but it did not weaken them, and yes i agree with you, you can shift at 6,500 if you're racing, but just driving around I would keep it at 6k.
 
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1Kona_Venom

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I know once you start modding the 13/14s you should only rev them to 6k, but with $1,500 in mods on a 13/14 and you're almost 700whp. It cost a lot more to get a 11/12 to that level.

Always, respect your input on the board etc.

For our folks who are just passing through, reading, and learning.... it does take more $ to get the 11/12 to the power level of the 13/14. However, initial purchase price of the car, being an 11/12, will determine in the end if you came out cheaper than a 13/14 stock or mildly modded. And it can be done.

Again, you always have good points and I needed my post for the day
 

1 Alibi 2

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Having had an 11 & 14, & both were modded to around the same level, I'm not sure where this info is coming from. As far as my tuner was concerned, ( JDM ), both were safe @ this level with a stock bottom end.
 

Klaus

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The cylinder liners are very thin in a 5.8 block. Not alot of sealing between the piston bores etc. Id personally take an 11-12 block with a standard bore over a trinity block any day.

They are both spray on. Are you saying the spray on 5.4 is thicker than 5.8?
 

96gt02

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I think people are slightly confused on this topic as both engines have roughly the same popping point but the 13/14 can get there much easier since they came more "maxed out" from the factory and a few tuners even claim they will knock on pump gas with just a smaller pulley. I have also heard of many more 13/14 blowing up then 07-12s but that may just be on the owners more then anything.
 

2011 gtcs

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Always, respect your input on the board etc.

For our folks who are just passing through, reading, and learning.... it does take more $ to get the 11/12 to the power level of the 13/14. However, initial purchase price of the car, being an 11/12, will determine in the end if you came out cheaper than a 13/14 stock or mildly modded. And it can be done.

Again, you always have good points and I needed my post for the day
Thanks man, I appreciate it. And I completely agree. You can pick up a 11/12 quite a bit cheaper and put the extra money into mods.
Having had an 11 & 14, & both were modded to around the same level, I'm not sure where this info is coming from. As far as my tuner was concerned, ( JDM ), both were safe @ this level with a stock bottom end.
Agreed, it's good hearing from someone who has had both.
They are both spray on. Are you saying the spray on 5.4 is thicker than 5.8?
Yes the 5.4 cylinder walls are thicker, to get the extra displacement for the 5.8 they bored out the cylinders and put bigger pistons in but they both use plasma lining.
I think people are slightly confused on this topic as both engines have roughly the same popping point but the 13/14 can get there much easier since they came more "maxed out" from the factory and a few tuners even claim they will knock on pump gas with just a smaller pulley. I have also heard of many more 13/14 blowing up then 07-12s but that may just be on the owners more then anything.
My guess why people see knock a lot sooner on the 5.8s is because of the extra compression. Once you pulley down the timing should be kept conservative unless you run E85 or 100oct.
 

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