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personally, I'd be worried about longevity in a stock block. With that big a stroke, end up with a heck of a tractor motor. the 4.5 stroke combo would be killer in an IA2 block, that's basically where quite a few of the forged 4.5 cranks have been used. Std bore IA2 would yield a 534.
 

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Thanks, sadly im only a college student with limited funds so ill have to wait to get a IA2 block. So when you mean longevity are you talking like 6-10 years or a shorter timespan? Im not using if any kind of racing, just want a power and torque heavy street beast.
 

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Thanks, sadly im only a college student with limited funds so ill have to wait to get a IA2 block. So when you mean longevity are you talking like 6-10 years or a shorter timespan? Im not using if any kind of racing, just want a power and torque heavy street beast.
Like all engines, keeping RPM's down will provide longevity. You can build the stroker engine to spin 6,000 RPM's and more, but you would do better to build the stock block engine with a lower RPM range in mind and take advantage of the gobs of torque the 4.25" stroke will give. So you build for torque, not HP, and you gear the car for lower RPM's to match the engine.

My Opinion never having done a Pontiac stroker - I would shoot for a 5,000 - 5,200 RPM engine using the 2-bolt main block. Use ARP main cap studs.

BUT, The limiting factory will probably not be the RPM's, but the heads. 487 cubes needs air. If you plan on using the stock heads, you may find that 487 cubes will run out of breath below 5,000 RPM's. To reach 5,000 RPM's, you will probably need at least a modified iron head that flows 240 CFM's.

That said, the stroker kit may not be the best choice if you are on a budget unless you plan on putting some money into the entire engine to include modified iron or aftermarket aluminum heads IF you are going for all out performance. On the other hand, if you are OK with gobs of torque and lower RPM's - which will mean engine longevity - then a stroker kit would be the ticket. Gear the car accordingly and you will still have a fast car.

Email whomever you are thinking of buying your stroker kit from and ask them their recommendations with the project build you have in mind. They can provide better answers than I can as they build engines all the time. :thumbsup:
 

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That's pretty similar to the build I just did. I went with KRE heads cnc'd to 340. And I should have went more. Changing intakes right now cause mine is choking it off. There's a million and one things. Are you looking for a daily driver weekend warrior strip? I dialed my cam down could have gone bigger but wanted good street manners. But have to install a vacuum pump there have been nothing but bugs I've been working out which is normal don't get me wrong. But a torque monster like that your problems get expensive. Figure out what you want to do with the car. Look at different combos on here and other sights and ask questions.
 
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