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GT350 Heads on 302?

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cholmes1

400lb Gorilla
350
216
Denver, CO
Was curious if anyone has installed or seen a Boss with the new GT350 heads?

https://performanceparts.ford.com/part/M-6050-M52

If I am reading correctly it looks like they will fit the 5.0 Coyote/Roadrunner engines.

With the required cams I am curious what gains could be seen, especially when paired with the CJ intake and long tubes.

Thanks
 
380
2
2015-12-12_16-26-27.jpg

From the most recent PRI expo at the Ford Performance booth. Numbers are with headers and a 100 octane tune, but impressive none the less.

If the motor in my Boss went south, I'd strong consider the 5.0L option listed above.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
4,008
1,924
Exp. Type
W2W Racing
Exp. Level
10-20 Years
Cookeville TN
Ford Performance has a 1st Gen - 2nd Gen handbook on parts compatibility for the Voodoo/Coyote engines from 2011-2016. I don't have the link but I think Rick may have posted it. Very informative as there are many nuances between the years especially the cam drives that need to be considered. The answer is yes the new heads can work on the older blocks but parts selection is key.
Steve
 
160
110
NJ
Everything I could gather from talking to FP employees at Carlisle indicated that a S550 cam setup would not work on earlier cars. If that's true, then not sure what options that leaves for using the 5.2 heads.
 

cholmes1

400lb Gorilla
350
216
Denver, CO
Berol said:

Very interesting, this paired with the PDF answers my question. I agree with you that, if and when the 302 starts to weaken, this type of buildup could be pretty amazing. I also liked that they ran the 302 north of 8K showing that it can be done and still generate good power.
 
Just as a point of note, I was able to still fit my CJ intake onto the 2015 heads. It required some force, but it does clear and sits flush with the heads. You can get a new set of 2015 heads and a Stage 2 porting and valvetrain work for what you can get for the GT350 heads just as a point of note and I didn't any revised head gaskets. I went with off the shelf Cometic .040 gaskets, but even the factory 5.0 or Boss head gaskets should work as well. I'm not sure if those are cheaper alternatives over the Cometic or not.

You also wouldn't be limited to camshaft design as I believe I recall reading the GT350 heads used a specific cam that Ford Racing designed, but I could be wrong about that not to mention you would still need the followers and lash adjusters for the 5.2 heads as well. I do like the Vlave setup that the GT350 has as it is the same as the Boss and I do believe I remember reading about them doing some additional work to the heads to make them slightly lighter then the factory GT heads. I'm curious to see what the flow rates would be compared to my heads since we are both pretty similar in combustion chamber size although I do have a bit more then the GT350 does.
 

ArizonaBOSS

Because racecar.
Moderator
8,730
2,734
Arizona, USA
Sean said:
Just as a point of note, I was able to still fit my CJ intake onto the 2015 heads. It required some force, but it does clear and sits flush with the heads.

Please elaborate. :eek:
 
Hah well, I just hit it with the top of my hand kind of gently like you were hitting the bottom of a ketchup bottle and it slid right into place and bolted up perfectly fine. I didn't notice anything was off. When I took it off to ship the motor to JPC I didn't notice any marks or anything on the gaskets or on the manifold itself so I think that the Cobra Jet will work without issue. I'm not sure about the other IM's though.
 
680
215
Theviking said:
Everything I could gather from talking to FP employees at Carlisle indicated that a S550 cam setup would not work on earlier cars. If that's true, then not sure what options that leaves for using the 5.2 heads.

I just confirmed from inside of FP that there a set of Cams being developed right now to allow the use of GT350 heads on a generation 1 (2011-14) engine. This would mean that they would be compatible with cam phasers of Boss engines. The intake cammid-lock phasers of the Gen II engines is the major hurdle since it requires Gen II cam phasers that are not compatable with GEN 1 ECM or wiring harnesses. Stay tuned.

Big Ass Taco
 

cholmes1

400lb Gorilla
350
216
Denver, CO
A few questions...

1.) Does anyone know what pistons and connecting rods are used in the OEM Boss motors?

In looking at the picture provided by Berol (post #2) and at the 2013-2016 Super Cobra Jet tech specs it appears that using Mahle Forged Pistons and Manley Connecting Rods are in every SVT modified engine. I see the GT350R uses what they just call GT350 forged pistons, but I am curious if they are simply Mahle pistons made for Ford. I would assume ours are cast and not forged.

Here are the tech specs on the CJ setups if you were curious:

http://www.americanmuscle.com/frpp-sc-cobrajet-engine.html#customer_pics-0

https://performanceparts.ford.com/part/M-6007-SCJ16

Assuming we do not have forged pistons or high strength connecting rods...

2.) What is the benefit of swapping them in all of the SVT CJ engines (both forced and non-forced) and in the basic GT350 head swap in post #2?

I was under the belief that our motors were perfectly fine using whipple setups up to 9psi without issue, but now I question that thought.

3.) Finally, in looking at the at the post #2 graphic is states that it was done with long tubes, a tune, and 101 octane fuel. Given that, are these gains really that impressive when compared with the non-FI CJ swap under similar parameters? (To my knowledge none of the write-ups used 101 octane which would certainly bump up values)

Write-Up 1: http://www.enginelabs.com/news/ford-racing-builds-the-ultimate-boss/

Write-Up 2: http://www.mustangandfords.com/how-to/engine/1406-boss-302-bolt-on-upgrades-haul-natural/

Ultimately, based on Seans post "You can get a new set of 2015 heads and a Stage 2 porting and valvetrain work for what you can get for the GT350 heads just as a point of note and I didn't any revised head gaskets. I went with off the shelf Cometic .040 gaskets, but even the factory 5.0 or Boss head gaskets should work as well. I'm not sure if those are cheaper alternatives over the Cometic or not. " I wonder if the GT350 heads really do anything that unique.

Thanks for your knowledge.
 
voodoo child21 said:
For all things Coyote read this publication from Ford.
http://performanceparts.ford.com/download/pdfs/Gen_2_Coyote_Technical_Reference_2-16.pdf

Steve

This is awesome. Is there anything like this that compares the Gen2 Coyote vs the "Road Runner"? I'm currently contemplating switching from my 2014 GT TP car to an S550, 2013 Boss or if I'm really lucky, GT350 (won't pay ADM so not likely).

Very cool how they are showing (and selling in some cases) the Voodoo intake and heads with the 5.0.
 
voodoo child21 said:
For all things Coyote read this publication from Ford.
http://performanceparts.ford.com/download/pdfs/Gen_2_Coyote_Technical_Reference_2-16.pdf

Steve

So it appears that most of the 12/13 Boss (Road Runner) features less the forged pistons and intake have been rolled into the current standard Coyote. I see the heads are not CNC's anymore but now an improved casting that is said to be about the same, most likely done for mfg cost reductions. I would expect more to come as the Coyote and the 5.2 continue to mature.
 
680
215
ArizonaBOSS said:
I'm not sure of the grade but the 2015+ Mustang GT heads are absolutely aluminum.
Yes, I should have been clear, I was trying to point out that Boss heads were made of a different grade than the GT gen 1 heads......
 

Senderofan

Having more fun than should be allowed..in my Boss
BigTaco said:
I think that the new heads are not 356 Aluminum (Boss 302 Heads are).....

I'll list a link to the article....but here's what I found:

"Most basically, the Boss head is cast from AS7GU aluminum--what we hot rodders know as 356 aluminum, with a little bit of added copper for increased heat transfer, while retaining the high strength properties of 319 aluminum. It's the same stuff used for the 6.7-liter diesel Scorpion heads, if that gives you a better idea of its capabilities."

http://www.mustangandfords.com/car-reviews/m5lp-1108-2011-ford-mustang-302/


Wayne
 
Senderofan said:
I'll list a link to the article....but here's what I found:

"Most basically, the Boss head is cast from AS7GU aluminum--what we hot rodders know as 356 aluminum, with a little bit of added copper for increased heat transfer, while retaining the high strength properties of 319 aluminum. It's the same stuff used for the 6.7-liter diesel Scorpion heads, if that gives you a better idea of its capabilities."

http://www.mustangandfords.com/car-reviews/m5lp-1108-2011-ford-mustang-302/


Wayne

That's correct, this material is higher quality (read more $$) so combine that plus eliminating the CnC expense would be why the gen 2 design was changed. Engineering is always tasked with cost reductions while maintaining performance goals.
 

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