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conman 06-09-2002 09:04 PM

Chevy72402
 
I read in your signature that you just rebuilt your 402. What kind of build up did you do. I also have a 72 402 bb in my longhorn. I'm thinking about rebuilding in the future.:bowtie:

chevy72402 06-09-2002 09:30 PM

I have keith black hyperutectic pistons with a .800 raise, a comp cam extreme energy 262H cam, a weiand action plus intake manifold, proform hei distributor, I had it balanced, polished, the only thing that I didn't have done was have it deckplated. I am thinking about going to a holley street avenger carb 670 cfm is what tech support said to use. I like my edlebrock but want a few more ponies and more throttle response so I am going back to the Holley. I had it bored over 40 also

chevy72402 06-09-2002 09:35 PM

oh yeah I also redid the valve guides and put new spings and I think they were manley valevs in. I had the seats ground. Needless to say I wanted to do this one time and do it right!

conman 06-10-2002 07:20 AM

Ponies and torque
 
You have any idea how much at the rear wheels? What kind of difference do you notice?

chevy72402 06-10-2002 02:47 PM

no idea as of now. I have been breaking the engine in slowly and don't want to blow it appart. I do notice a difference though. Having everything balanced and blueprinted really makes it a lot smoother and more torque. Can't wait to get my new carb. I will probably order it today! wohoo another $400.00

Orence1 06-10-2002 04:09 PM

I have a 402 built very much the same way. I might have a bit more work done on the heads but I have the KB pistons and a similar cam set up. My builder who is a race guy tells me that I need at least a 750 cfm carb. I had a Holley 750 custom built for it. Are you sure the 650 cfm carb won't restrict that all important airflow you need to unleash all that power? Just another viewpoint for you to consider.
Larry

chevy72402 06-16-2002 02:28 AM

That is what the guy at Holley told me anyway... I am not sure. I haven't bought it yet so I guess it's on hold till I find out more info. What else did you have done to your heads?? I wanted to keep a stock appearance (even though I had to buy a new intake cause mine was cracked) but yet build it to last through me and generations to come.

LILREDGMC 06-16-2002 10:22 AM

Heads
 
Which casting number heads are you using. Open or closed chamber? Have an estimate on CR? Mine is still at the shop, waited for 030 bore.:bowtie:

chevy72402 06-16-2002 02:11 PM

I left my receipts in Michigan at My fiance's house.... I will have to get them.... dang it! as for casting numbers I don't remember what they were. I know that they were the factory ones but not sure what style.....

batboy 06-16-2002 11:25 PM

Most hotrodders will use a 750 CFM carb on a big block. But, if you want good low end torque and have a fairly mild cam (like the 262H), there is nothing wrong with using a smaller 650 to 670 carb. You don't want to use high revs with those big blocks anyway and the big carbs are more for full throttle, high RPM stuff. For trucks, I like the small valve oval port heads (open chamber if you can find them), a good cam for low and mid range, headers, and a modest carb. Talk about a stump pulling torque monster.


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