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Discussion Starter #1
This weekend on track at NJMP, I broke cylinder #7 rocker and valve, head is toast, piston is toast. Time to tear down again. Literally cried after pulling the valve covers. It took an entire year to research, build, machine, this internally balanced 306. If the windsor experts can hop in here, looking for advice, since I was on gt40x heads and the driver side head is gone, its time for me to pick a real race head AFR or TF 11R, im praying the block is ok, and the rotating assembly. My plan is order 1 piston and rebuild, I need to figure out which head and maybe go to the TF box r intake...


Thanks guy
 

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I'm certainly not an expert, but AFRs and TWs are two very good heads.

If you are able to salvage the shortblock and only have to replace one piston, the an inline head like AFR would seem to be a good choice,
otherwise its 8 new pistons for TW heads.

Good Luck, decisions on heads are always tough ... so many choices and even more opinions. :wink2:
 

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Discussion Starter #3
I'm certainly not an expert, but AFRs and TWs are two very good heads.

If you are able to salvage the shortblock and only have to replace one piston, the an inline head like AFR would seem to be a good choice,
otherwise its 8 new pistons for TW heads.

Good Luck, decisions on heads are always tough ... so many choices and even more opinions. :wink2:
Thanks

I have icon forged flat top pistons with big valve reliefs in them, cam lift is .555/.565 I believe id be good for the 11R (obvi would verify clearance and talk to a rep at TF before buying)
 

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Just swap a stone stock 2011 5.0 DOHC in it. You won't break it and it'll make way more power than you had with the 306. 7000 rpm capable from the factory. Basically a racing engine from the production line. For even better results use the so called 2nd Gen version ('15-'17) they have improved heads, rods and , I think, cams over the debut version. More like the BOSS engine.
 

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Just swap a stone stock 2011 5.0 DOHC in it. You won't break it and it'll make way more power than you had with the 306. 7000 rpm capable from the factory. Basically a racing engine from the production line. For even better results use the so called 2nd Gen version ('15-'17) they have improved heads, rods and , I think, cams over the debut version. More like the BOSS engine.
It would be cheaper to do the head swap, and be almost just as fast. To do the Coyote swap he would need a hydroboost brake system, new k-member, transmission and driveshaft even if the Coyote Engine is used.
 

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Damn man sorry, that’s really ####ty. I remember just reading your dyno thread the other week.
 

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Sucks man. I blew up a 363 that I had built after leaving the Dyno. Maybe had 10 miles on it. I was sick so I know how you feel.

I’d vote for 11r’s. Maybe hit up Ed and have him do a package deal for heads, cam, intake. People seem to make pretty good power with the box r, 11r’s, and custom cam on the stock stroke combos.
 

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This weekend on track at NJMP, I broke cylinder #7 rocker and valve, head is toast, piston is toast. Time to tear down again. Literally cried after pulling the valve covers. It took an entire year to research, build, machine, this internally balanced 306. If the windsor experts can hop in here, looking for advice, since I was on gt40x heads and the driver side head is gone, its time for me to pick a real race head AFR or TF 11R, im praying the block is ok, and the rotating assembly. My plan is order 1 piston and rebuild, I need to figure out which head and maybe go to the TF box r intake...


Thanks guy
Lots of info in here the last time you asked..

https://forums.corral.net/forums/5-0-5-8-engine-tech/2480600-i-really-dont-want-keep-beating-dead-horse.html
 

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My car sat for 7 years. Finally got a break and got the money to get it running. Busted my ass for about 2 months to get rolling and it lasted less than a week before I cracked a cylinder on the highway like I was james bond and hit the smoke screen.. Had to wait till next year with a new shortblock..

You need to find out why or how it failed.
 

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I would keep the Holley intake rather than spend any more money on an R - I realize you can sell the Holley to help off set. Just my opinion..........
A valuable opinion...

Everybody has had a build fail. Do your homework, suck it up, re-use what you can, worse case go stock short and beat the hell out of it. You already did all the hard work, a straight up rebuild will go much easier, quicker, and cheaper than the first unless you get caught up in upgrades.
 

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Discussion Starter #16
Just swap a stone stock 2011 5.0 DOHC in it. You won't break it and it'll make way more power than you had with the 306. 7000 rpm capable from the factory. Basically a racing engine from the production line. For even better results use the so called 2nd Gen version ('15-'17) they have improved heads, rods and , I think, cams over the debut version. More like the BOSS engine.
you sound like 50% of my friends and the other 50% say LS...im so invested in the sbf to start over...
 

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Discussion Starter #17
I stand by opinion. And this is a race car, which I think the OP has put manual brakes in. I think I read he did in another thread.

i thought about manual and possibly will do them eventually, but shes still vacuum assist,
 

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Discussion Starter #18
Damn man sorry, that’s really ####ty. I remember just reading your dyno thread the other week.
yup

2 fridays ago dynod 600 bucks
last friday redynod with 30lb injectors 360
saturday (a day later) break engine, 3 hours from home
 

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Discussion Starter #20
My car sat for 7 years. Finally got a break and got the money to get it running. Busted my ass for about 2 months to get rolling and it lasted less than a week before I cracked a cylinder on the highway like I was james bond and hit the smoke screen.. Had to wait till next year with a new shortblock..

You need to find out why or how it failed.

This is how it failed:


1. stock gas tank, going around the spoon at NJMP Lightning my AFR's went lean, and my oil pressure dropped to 20psi (i believe i was low on oil)
2.stock rockers with 150,xxx miles on them (i dont know wtf i was thinking)
3. with low oil pressure and lean AFR's the valves must have got really hot and fatigued.

#7 valve broke, which caused the rocker to break, and piston getting smashed, and head getting smashed.
 
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