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-   -   Another 489bbc question (https://67-72chevytrucks.com/vboard/showthread.php?t=623646)

Blue Rat 04-13-2014 09:28 PM

Re: Another 489bbc question
 
You could take a 454 an bore .060 an get a 468 add 4.25 crank an you have a 496.

Roll'nSlo 04-13-2014 09:42 PM

Re: Another 489bbc question
 
Ok. That's what I thought. I just don't want to bore it .060 just incase something happens and I need to bore it again.

68c10owner 04-14-2014 12:33 AM

Re: Another 489bbc question
 
Quote:

Originally Posted by Roll'nSlo (Post 6627513)
Ok. That's what I thought. I just don't want to bore it .060 just incase something happens and I need to bore it again.

If you have your block sonic checked and its thick enough some 454 blocks can got .125 over.

Blue Rat 04-14-2014 06:43 AM

Re: Another 489bbc question
 
Quote:

Originally Posted by 68c10owner (Post 6627783)
If you have your block sonic checked and its thick enough some 454 blocks can got .125 over.

Yep.

Roll'nSlo 04-14-2014 07:17 AM

Re: Another 489bbc question
 
May do that to squeeze a little more out of it if possible.

Blue Rat 04-14-2014 07:42 AM

Re: Another 489bbc question
 
The 468 will be more than enough if you decide to go that route.

bbcmudtruck 04-14-2014 08:29 AM

Re: Another 489bbc question
 
If you have a standard bore block that will clean up at .30, go that route. No need in boring the block more than needed. Your not going to miss the difference between the 489 and a 496. If your starting from scratch, get ahold of cnc motor sports for a rotating assembly. They are truly balanced in house before shipped to you. Unlike jets or summit. Ideally, you'd want a 4.25 stroke crank, 6.385 rods and pistons to match accordingly. I prefer scat assemblys, but anything can be broken if abused! You'll need your rotating assembly before you take your block to the machine shop. Almost forgot, if it hasn't been mentioned yet, be sure to get an internal balanced crank. You'll need a neutral flex plate and 427 harmonic dampner.

Kyle@FTP 04-16-2014 10:33 AM

Re: Another 489bbc question
 
Quote:

Originally Posted by Roll'nSlo (Post 6627898)
May do that to squeeze a little more out of it if possible.

If your going to put it on the bottle, Make sure you plan for that. If its just a 100 shot you will be fine with most parts but anymore and you will want a solid piston/rings and the cam will be a little different as well.

Quote:

Originally Posted by bbcmudtruck (Post 6627958)
If you have a standard bore block that will clean up at .30, go that route. No need in boring the block more than needed. Your not going to miss the difference between the 489 and a 496. If your starting from scratch, get ahold of cnc motor sports for a rotating assembly. They are truly balanced in house before shipped to you. Unlike jets or summit. Ideally, you'd want a 4.25 stroke crank, 6.385 rods and pistons to match accordingly. I prefer scat assemblys, but anything can be broken if abused! You'll need your rotating assembly before you take your block to the machine shop. Almost forgot, if it hasn't been mentioned yet, be sure to get an internal balanced crank. You'll need a neutral flex plate and 427 harmonic dampner.

I never got the internal/external balancing. Ya sure its great to have the assembly balanced with less weight on the ends of the crank. But for a 500hm application? does it really matter that much? If he goes external he can reuse his balancer and flex plat that he has, saving a couple hundred bucks.

bbcmudtruck 04-16-2014 01:13 PM

Re: Another 489bbc question
 
Internally balanced is much better than having weights slinging around on the outside of your motor! No matter the hp rating or even intended use, it's better. Now will the motor be fine externally balanced? Absolutely if done correctly! It will also save him a little bit of money, IF he already has a good balancer and flex plate. Just my opinion that if he's starting from scratch to do the little things to help the engine be more efficient and live longer as he goes. Again, just my opinion.

Roll'nSlo 04-16-2014 04:22 PM

Re: Another 489bbc question
 
I have a complete engine plus accessories. But I'm not going to use the accessories. I'm going to internally balance it. I'm replacing all of the rotating assembly.

Roll'nSlo 04-18-2014 08:06 PM

Re: Another 489bbc question
 
Quote:

If your going to put it on the bottle, Make sure you plan for that. If its just a 100 shot you will be fine with most parts but anymore and you will want a solid piston/rings and the cam will be a little different as well.]
If I do add the bottle, it'll only be 100 shot.

Kyle@FTP 04-19-2014 11:48 AM

Re: Another 489bbc question
 
Quote:

Originally Posted by Roll'nSlo (Post 6635341)
If I do add the bottle, it'll only be 100 shot.

Just buy quality parts and retard the timing 4* and you are good to go.


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