[HORSMEN1995]

What can i bore my 5.0 out to?? im lookin to bore and stroke it, jus dont know to what.... ne one have ne numbers that u like personally??

[Screemin3o2]

most people believe the max on the newer 302 blocks, the max you should bore it is .030". Don't quote me on this but I have heard some of the older carbed blocks can be more. I wouldn't go any higher than .030" on the 87+ blocks. The two most common strokers are 331 and 347. A lot of people say 347 has too much of a stroke. I disagree with that 100%. 347 is what I would go.

[MSO]

Originally Posted by Screemin3o2 most people believe the max on the newer 302 blocks, the max you should bore it is .030". Don't quote me on this but I have heard some of the older carbed blocks can be more. I wouldn't go any higher than .030" on the 87+ blocks. The two most common strokers are 331 and 347. A lot of people say 347 has too much of a stroke. I disagree with that 100%. 347 is what I would go.

wut do u hav?

[Tony_90fox]

mine is bored 30 over to a 306, but for some reason, i think i have heard people going to 60 or even 90. i am not for sure though, maybe i was just imagining that. but that does sound familiar!

[1slo5.0]

Originally Posted by Screemin3o2 most people believe the max on the newer 302 blocks, the max you should bore it is .030". Don't quote me on this but I have heard some of the older carbed blocks can be more. I wouldn't go any higher than .030" on the 87+ blocks. The two most common strokers are 331 and 347. A lot of people say 347 has too much of a stroke. I disagree with that 100%. 347 is what I would go.

I agree 100%. 80s and newer blocks are thin. Early blocks can go .060 max. Go big or go home. If you are going to pay money to stroke it, put the biggest crank you can get for the money in there.

[88BlueGT]

I wouldnt recommend going over .030 bore.

Also, to be totally honest I think stroking a 302 is retarted. For the money and effort you are going to put into a 302 you can build yourself a 351W with more power and ALOT more room to grow power wise.

[1slo5.0]

Sonic checking is the only way to determine how far you can bore a block. As far as a 302 based stroker being a waste, LOL! The 347 that was in my car when I bought it made almost 1.8 hp per cubic inch. If that is a waste of mine, I'm going to throw in the towel....

[88BlueGT]

Im not saying that they are a waste because you can build 10 second 347 strokers all day long if you wanted to. Im just saying, if I were to ever pull my motor and have it machined, etc. I would rather just get a 351W and stroke THAT to a 393, 408, 418 or 427W. You might spend a few hundred more with converting your car to work with the 351W (oil pan, headers, lower manifold, etc.) but most of the time when you do that kind of work you replace all of that with aftermarket parts anyway... just order them for a 351W and your all set. Thats just my opinion. Dont take this the wrong way, I love ANY stroker motor but I just think its alot smarter to go with a 351W instead of a 302.

[Paulownian]

I believe that 88BlueGT is basically correct - if you are just looking at the two engines side by side and not taking into account any others factors. If you add in the type of driving, type of activity planned, and the type of vehicle you will using the engine in, then you begin to add more serious elements to the equation. I, for example, plan on simple street/strip applications just for the fun of it; not for profit, or any other higher goal. My driving skills are in the medium level at the very best, as well. My vehicle is going to be the Factory Five Roadster, so do I need more than 435hp in that vehicle? If this were the original Cobra, then I might want to go to 427, but this is a lightweight racing frame with a fiberglass outer skin. I'll stick to a stroked and bored 302, thanks. There may be others whose applications fit better with the 302 than with the 351. Everyone has to make up their own mind on this question. Now that I have bored everyone to death with a rambling answer, the bottom line is this: if I were building an engine for a heavier vehicle I would probably go with a 427. For a lighter vehicle I would stay with the 302.

[88BlueGT]

I understand what you are saying BUT I dont understand this...
Iif i were building an engine for a heavier vehicle I would probably go with a 427. For a lighter vehicle I would stay with the 302."

Whats the difference? The 351W is only approx. 80lbs heavier than a 302. Thats nothing. I just dont get why you WOULDNT want a 351W. Most 351W blocks are good for an extra 200rwhp over a 302. And if you are pulling the motor or putting a new motor in a car why not get it for an extra $100 bucks that its going to cost you to get the block? But hey, its not my car so whatever floats your boat lol

[Paulownian]

Consider the power. When is too much, too much? Why build something that defeats the purpose of the application? In other words, if you engine is too powerful for the vehicle, why would you use it? Why not step down to an appropriate size and be able to apply all of the power?

[88BlueGT]

You dont HAVE to stroke a 351W. You can just drop a 351W in there, throw a nice h/c/i package on it and be done with it. My point is, if you are going to pull your motor and send your block away to a machine shop, etc. why not get a better block w/ more cubes for maybe a hundred dollars more? Than if you DO decide you want more power you have it there because your block can support it... not like a 302 block where you hit 450rwhp and you have to back off because you are taking a risk of splitting it.

[Paulownian]

Well, I do see your point. But I would still have to send the block out for balancing, and the heads for porting. So, either way I will still have $$$ invested in after-purchase work. Besides I already have a new 302 block and new heads )at least I will in a few days - I need to pick them up from the seller).

[88BlueGT]

You are going to port the stockers? Who is doing it and how much are they charging you? Did you ever just consider buying a used set of aftermarket aluminum heads? They would be alot better...

[Paulownian]

I'm not ruling out any options. I am researching all of the different choices to see which will give me the best results. So far, I have talked to TA Racing, Tri State Cylinder Heads, Power Heads, and a few others. I am seeing prices from $600. per set, to a couple of thousand exchanged. My range is $1,000 total for the heads. I want to spend the rest on the block, EFI, exhaust, gears, etc. I have even thought about CNC-ported twisted wedge aluminum cylinder heads from Trick Flow.

[88BlueGT]

Twisted Wedges are VERY good heads! If you have 1K to spend I wouldnt even think twice about going with a set of twisted wedges. Plus they have alot of room on them if you want to port them. A brand new set will set you back about 1300 though so used will be your only option BUT I am sure you can find a set of uninstalled tw's for 1K.

[Paulownian]

I found a set of street style for $1,175. Porting will add another $800 approx. So, I would have almost $2,000 in my heads. I suppose I could spend that.

[88BlueGT]

Why would you spend 2K? You can get an off the shelf twisted wedge head and that would work very well.

[Screemin3o2]

Originally Posted by My'StangOpens wut do u hav?

just a bolt on 302

[HORSMEN1995]

well shit, thanks fo all the input.... well the motor is gonna go into my 95GT and i dont relli wanna step up and mdify everything for a 351W, i would like to stay and bore and stroke the 302 to 347. and another question, if i go the max bore and stroke out of a 302 block, what problems would that cause if later down the road, i get a bug to supercharge?? would that be putting too much on that block?