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-   -   building a 69 396 (https://67-72chevytrucks.com/vboard/showthread.php?t=467761)

wicky 06-03-2011 03:39 PM

building a 69 396
 
I want to hop up my 396 in my 69 cst. I would like to build it to scream like a small block hold on to ur pants n throw ya in the seat. But I dnt really know where to start. I know im goingto switch it to hei distributor probly a holley carb and would like to try the lunati 4-7 swap cam. I want to stick with pump gas, maybe ad a shot of air plane fuel. Plan on putting a stall in it maybe even a 700 r4 for the overdrive. I want a QUICK throttle and pop off one crank. Any opinions would much appreciated
thanks nick.
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clinebarger 06-03-2011 07:38 PM

Re: building a 69 396
 
Unless your building a "numbers matching" truck, A small C.I. big block is a waste of money. Get a GOOD 454 block & reuse your crank/rods with 427 pistons & build a 427. ***you will need the rotating assembly balenced***

wicky 06-03-2011 10:31 PM

Re: building a 69 396
 
Yes my truck is all numbers matching even has the original sheet metal. And I would like to keep it that way. Although yes it wont be original it will still have the same motor in it and would like to keep it that way
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prostreetC-10 06-04-2011 01:40 AM

Re: building a 69 396
 
Man I hate to burst your bubble but if that is the original 396 that came in that truck, you are peeing against the wind. I just went through this. Your heads are going to kill any power gains attemp. At minimum, you would need to get better heads. A 396 is not a 396. In other words, these are not like the Camaro and Chevelle motors. These are built for torque down low with not my top end at all. You would be soooooo much better off to get a early 454 truck motor that will come with big 049 or 781 heads and build a stump puller. I have 2 and they flat rip. Take the original motor and put it in the corner of the garage. I promise no one will come up and try to verify the numbers on your block. 396s should almost be taken off the BBC list and put on the heavy small block list in times of 496-572 motors. You just won't get a good return on the money spent. Hope this helps.

Blue Rat 06-04-2011 09:09 AM

Re: building a 69 396
 
If you want to build the 396 then build it. Decent cam an lifters an intake. Have it balanced. The 396 was the way to go 35 or 40 years ago. But with the technology today its not thought as much as it use too. But, you could still build one to run good.

prostreetC-10 06-04-2011 09:37 AM

Re: building a 69 396
 
Quote:

Originally Posted by Blue Rat (Post 4716873)
The 396 was the way to go 35 or 40 years ago.


If you read his original description, he is not going to achieve his goal by keeping his original block and heads. A cam and intake isn't going to do squat with those heads. It will be another disappointing maiden voyage. Motors are air pumps and it's like trying to fly a kite without wind.

wicky 06-04-2011 10:16 AM

Re: building a 69 396
 
Wow didn't realize he 396 was such a disappointment. But at the same time wouldn't it be cheaper just to get a set of heads rather than buying a 454 and overhauling it to. Im sure im going to spend atleast 500 on another motor
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Blue Rat 06-04-2011 10:34 AM

Re: building a 69 396
 
Its not a disappointment. It is just that things have advanced so far that they are not the cream of the crop so to speak. Back then when they came out they did not have 431 small blocks like they do now. You could get set of heads for it. That would help it rev higher an breath better. Or, like someone else said earlier. If you could find a 454 block. Then you could take the rotating assembly in the 396 except the pistons. With a new set of pistons an a good set of breathing heads like the 781 or 049's you would have a 427 BBC. That's what I am building right now. Even the 427 is considered a small BBC now days since they have 500, 600 an 700 plus CI BBC's.

prostreetC-10 06-04-2011 10:58 AM

Re: building a 69 396
 
Quote:

Originally Posted by wicky (Post 4716946)
Wow didn't realize he 396 was such a disappointment. [/i][/size]

Once again the truck and car 396 are very different. You can get a little 325hp 396 CAR motor to cook with 702 or even the rec heads. Not so with the truck setup. Small valves and ports.

The big deal is that machining costs are machining costs. The machines don't know if they are working on a 396 or a 496. The rear tires will sure know a difference though. We are just trying to help your end result. I am someone that has your 396 in a heavy truck and a couple of '73 big oval headed 454s in a heavy truck. The power difference is AMAZING!

Blue Rat 06-04-2011 11:22 AM

Re: building a 69 396
 
I do not know what heads you have on the 396 right now. If you do have the small port heads an the small valves. Then it is not going to pull right past about 4500 rpm's. You would be much better off with a set of decent heads.

prostreetC-10 06-04-2011 11:49 AM

Re: building a 69 396
 
Correct......just when you are ready for that this to really start pulling, the motor will be past it's power range. They put this style 396 in these trucks for really good GRUNT!

The other thing that is a hang up on those is if you put a big ported oval head on with open chambers, you will kill your compression ratio and possibly wind up with even worse results. I consulted with quite a few people before deciding to leave the 396 alone. Every idea for power was squashed because of the whole motor picture.

I think the best thing you can do at this time is to pull a valve cover and give us the head casting number. Who knows, maybe someone did a head swap in the 40+ years that motor has been around. You really need to know what you are working with before you can plan for gains. Gotta have all the facts.

wicky 06-04-2011 12:15 PM

Re: building a 69 396
 
Yeah ill pull the covers off tonight
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prostreetC-10 06-04-2011 01:29 PM

Re: building a 69 396
 
Great and PLEASE understand we are not trying to crap in your backyard here. We are trying to help you not throw a bunch of money into something that will produce something other than what your first post said you were looking to do.

wicky 06-04-2011 02:16 PM

Re: building a 69 396
 
Oh I know. Im completely new to big blocks so I dnt know much about them anything helps
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