Anyone here ever crack a stock block??!!

90lxcoupe

20+ Year Stangneter :roc</strong><span class=
Oct 7, 2003
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im sure someone on this forum has either cracked a stock block or knows someone that has, and i am wondering how much power it took, and what thier combo consisted of. the reason i am asking is because i just had my car dynoed and it made 420 HP and 398 ft/lbs of torque, and this is not close to the hp i am going to get out of it because the car was in the process of getting tuned and it blew a head gasket. the shop owner told me he should be able to get 450hp at the wheels no problem, this kinda scares me because now i have to put new head gaskets on the car and then just crack the block right after i tear the motor apart.

has anyone had any expierience with the girdles that cover the lifter valley or the main support systems? any feedback is greatly appreciated.

any advice would be great because i am in a tricky situation right now.
 
From everything i've read, once your in the neighborhood of 450-500 rwhp, its a crap shoot. Some blocks hold, others dont. As far as girdles, from what i've seen, they just keep the pieces in together and can sometimes allow you to reuse your internals.
 
Read 5.0 and MM&FF, they talk about the stock blocks in a lot of their articles, they've had a lot of feature cars pushing over 500 WHP on stock short blocks, just get a extra super safe tune and double damn make sure you arent getting any detonation, cuz thats almost always why they fail under boost. Otherwisetry to keep the RPMs below 6000, it should be fine. Also get a good harmonic balancer. Check out this months Car Craft, there's a guy with a stock block 5.0 with AFR 185's knocking out 510 HP at 7100 RPM, although its N/A not blown. I think it has the factory crank too. In my "5.0L FORD DYNO TESTS" they tested a blown factory short block to 638HP at 6000 RPM.
 
:nonono: I had one split in half... But not from too much HP. Our 1990 Hatch was stolen from Jackson Mi. and almost made it to Mexico. Needless to say, high speed chase on some seriously bald rear tires and the car smacked a brick wall head on somewhere in the neighborhood of 100 ~ 110 MPH (according to the police).

The Jacka$$ that stole the car walked away with minor injuries but the engine split between the crank and cam at the front of the engine....and the rest of the car was pretty messed up too.


Sorry it's not even close to what you were asking about.
 
I know of two locals and about 1000000000000 people online that have cracked the stock block. It's known to be a pos. One was making 600 rwhp here, with a 347, alcohol injection, girdle, he found it split when he took it out to put a Dart block in it. Another split his with about 450 rwhp but he did run into detonation one time. Check www.turbomustangs.com

plenty of info on blocks there ;)
 
thats one of the reasons why i dont get why some guys spend all kinds of money on a complete forged(aka forged crankshaft) rotating assembly, AFR205 heads, kick ass intake and an S or better trim blower. its comes to the point where its just wasting the money on the stock block. a nice blower/turbo charger with around 12-14 psi and ported stock heads/intake can probably take you to block splitting levels, or near them. so there really is no point in adding all that money to the block. granted, a 185 afr, or similar head, with an RPMII intake manifold will probably generate 450 hp on about 10psi(ie less psi than the stock/ported head/intake combo needs to produce the same amount of powr) but you're talking about a grand or two more than you really need, not to mention the cost of a forged crank
 
I've seen 420RWHP NA crack a stock block, and I have seen a Ford Engineer post they have cracked them on the dyno completly stock....

It's a gamble, and just a matter of when...
 
this is basically the point of no return for me cause this car is getting real expensive real fasst. I dont even want to think about the stock axles in the rearend

thanks for all the advice, im just gonna throw some new gaskets in it and play it by ear