302 strength question

[CompOrangeSN95]

Hey guys, I got a 302 out of an explorer, as some of you know I'm building it into a 347, but before I start buying parts I want to know if the block can handle 500-550hp. Anyone have experience with this or know someone that has gotten that kind of power with the stock block?

 

[IceMan]

Well, here is the deal. Do you wanna be safe??? Than keep it about 500 RWHP and under 6000 RPM. A lot of people think that the horsepower is what kills the block. That is somewhat true but most importantly is the RPM's is what kills it. You can have a 450 RWHP car that you rev up to 7000 and the block will fail you faster than a 550 RWHP car that you rev up to 5500 RPM. Is the car going to be N/A or with a power adder??? N/A is going to be hard to make 500 RWHP without high RPM on a 347.

 

[CompOrangeSN95]

it is an N/A setup, I've been doing some research and it looks like 500hp is completely possible but like you said I'll be running high RPM 3500-7000 consistently... keep in mind the only thing that will be stock on the engine is the block itself, new heads, rotating assembly, cam... you get the idea.

 

[IceMan]

If you can do with a little bit less power and rev it to MAX 6500, than you should be fine. I would NOT rev it higher than that if you want it to last you a couple of seasons. But yet again, blocks are cheap and easy to find. Put a girdle in so the rotating assembly stays together and put it in another block as soon as the old one splits.

 

[two95s]

We ran two different stock block 347s in a circle track car. Both blocks failed. One engine was borrowed, and it exploded at the cam journals the first night out. The other stayed together but cracked in the main webbing and spun a main bearing after four or five races.. Got a r302 and didn't have any problems.

 

[All_Ford_Fun]

http://www.mustangsandmore.com/ubb/SteveWmaxpistonspeed.html

thats what ive been told several times now,how true it is im unsure of... i had a stock block 347 that was 7500 rpm motor and the block stood up good , just the rest of the motor didnt lol

 

[Javi]

you are doing it N A? deep pockets here lol

 

[CompOrangeSN95]

you are doing it N A? deep pockets here lol

haha tell me about it, without pricing the heads or cam I'm looking at $2,700. I'm starting to second guess the stock block... it is in perfect condition and I feel like if I'm using all the right components the block should hold up, but it's a lot of money for "SHOULD" haha

 

[IceMan]

Just keep it under 6500 rpm and you will be fine with the stock block.

 

[sn95gtvert]

i've seen first hand an explorer 5.0 stuffed into a fox lx with a procharger on 20lbs. he ran a custom cam, copper head gaskets and 1.7 roller rockers. heads intake all stock exploder. car made 476hp 560ft/lbs at the wheels, he's been driving it around for over 2 years now.

the 12 rib procharger made 6lbs of boost at idle, thing sounds like a jet engine on roids...

 

[LAFENATU]

Stock block can take 500HP with a safe tune.

Don't spin the sh1t out of it.

 

[mikey94gt]

Now you understand why I went with an aftermarket block.... Of course... you could get a late 60's (69 is the best) 351w block and go at it with a 408.....

 

[2slo95fiveoh]

I second the windsor Idea.. If you are just using the car for track usage, why not switch to a 351W?
a NA 408 would be very fun me thinks.

 

[CompOrangeSN95]

I would love to have a 351 but I got the explorer motor for free and it's practically new...

 

[mikey94gt]

True.... but.... you could probably trade said running, complete engine for a 60's 351w block....... and start with forged H beam rods, forged pistons and crank,add some Trick Flow race heads, a Parker Funnelweb intake, a custom grind cam in the .620 range with lotsa duration, and about 11:1 compression with some 2" long tube headers, EFI and coil on plug and be at 500hp pretty easily, with a whole dump-truck worth of torque........