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Looking for advice on new engine for ‘12 BOSS 302S

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Need some help guys. I’m just getting into this sport. I just bought a 2012 Boss 302S with a blown engine. I’ve spoke to several people about different engines, stock one, 5.0 Aluminator XS, Roush-Yates and a GT350 crate engine. Anyone on here have any other engines available before I pull the trigger on one of these or any suggestions on different engines? I’m planning on justdoing track events at VIR and eventually gointo NASA American Iron and SCCA.

THANKS!!!
 
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5.0 XS is unavailable and out of production (unless there is one sitting on a shelf in stock at a vendor somewhere). 5.2XS would be awesome but you would definitely have to swap out to FP gen one cams for GT350 heads and use gen 1 cam phasers. You may also have to change oil pans to make it work in a S197 chassis. That would be a screamer right there...
 
5.0 XS is unavailable and out of production (unless there is one sitting on a shelf in stock at a vendor somewhere). 5.2XS would be awesome but you would definitely have to swap out to FP gen one cams for GT350 heads and use gen 1 cam phasers. You may also have to change oil pans to make it work in a S197 chassis. That would be a screamer right there...

Thanks. I did find a 5.0 Aluminator XS with 200 Miles on it. Oh yeah I would love the 5.2, but I think A LOT needs to be converted over for it.
 
I’d grab that 5.0 XS quick and get it installed. The RY option would be nice too.
 
I can get the stock crate engine for $7500, the 5.0 Aluminator for $15,000 and the brand new left over 5.0 Roush-Yates for $17,500 and the crate GT350 engine for $17,500.
 

Grant 302

basic and well known psychic
Welcome to TMO!

I'd go for the stocker, maybe the aluminator. Is the ECU still on it's stock tune? Does it still have the OEM hand-held programmer (Procal)?

Do you know what happened to the original one and why it failed?
 

ArizonaBOSS

Because racecar.
Moderator
8,730
2,734
Arizona, USA
If you are willing to do some assembly work yourself, a very real option can be a 5.0L Aluminator "NA" (11:1) compression short block, paired with 2015 Mustang GT heads. If you are purchasing this stuff new it will all be "Gen 2" Coyote stuff, but there is a specific timing kit to allow you to use the Gen 1 cam phasers (needed to mate with your existing PCM). Top it off with a Boss 302 or Cobra Jet intake and you'll be hauling the mail in no-time. I would absolutely advise adding long tube headers while the engine is out, if not already equipped.

EDIT: Since your heads survived, I would highly advise getting the 5.0L aluminator short block and mating your existing heads to them. If you do not have a vendor partner already, I would suggest our friends at Paul's Automotive Engineering (Cincinnati) or KohR Motorsports (Westland/Detroit). They will have the knowledge to know what head-changing kits etc are required to mate these up.
I did the same thing but with a Gen 1 Aluminator short block and my stock B302 heads.

I strongly suggest refreshing the valve springs with a fresh set of B302 springs while everything is apart.
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
Agree with above. I do the same thing with a gen2 aluminator base, its absolutely the way to go if not a crate motor. The gen2 is basically the same deal, just a slightly different oil filter adapter (which is included). Otherwise drop in and go with the provisions @ArizonaBOSS described above.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
After reading all the TMO engine building stories and adventures, and being down here at the end of the world with my mediocre mechanic skills, convinced now that the only option for me in the future is a Gen 2 Aluminator. I guess switching to a gen 2 pcu etc would be an extra cost but worth it. Hoping it does not become a reality any time soon. After about 60 track hours the engine still pulls strong but I do hear more rattles then it had before...
Maybe a Gen3 crate engine will be out by then!
 
If you are willing to do some assembly work yourself, a very real option can be a 5.0L Aluminator "NA" (11:1) compression short block, paired with 2015 Mustang GT heads. If you are purchasing this stuff new it will all be "Gen 2" Coyote stuff, but there is a specific timing kit to allow you to use the Gen 1 cam phasers (needed to mate with your existing PCM). Top it off with a Boss 302 or Cobra Jet intake and you'll be hauling the mail in no-time. I would absolutely advise adding long tube headers while the engine is out, if not already equipped.

EDIT: Since your heads survived, I would highly advise getting the 5.0L aluminator short block and mating your existing heads to them. If you do not have a vendor partner already, I would suggest our friends at Paul's Automotive Engineering (Cincinnati) or KohR Motorsports (Westland/Detroit). They will have the knowledge to know what head-changing kits etc are required to mate these up.
I did the same thing but with a Gen 1 Aluminator short block and my stock B302 heads.

I strongly suggest refreshing the valve springs with a fresh set of B302 springs while everything is apart.

THANKS!!! A lot of great info!!!
 
If you don't go the RY's option, can you share who has the brand new left over 5.0 Roush-Yates for $17,500.

Make sure you replace the valve springs on your old heads.
 
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I’ve heard that if you use components from the 2015 - 2017 controls pack, you can retrofit the 5.2XS as is. My understanding is this is not a good option for a street car, but is doable for a stripped track car.

But, the simplest route is a leftover 5.0 XS or aluminator shortblock.
 
So unless ive missed something, nobody has mentioned mmr's 5.0 and 5.2 engines...is there a reason for that? Also, why would the 5.2xs not be good for a street car?
 

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