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Discussion Starter #1
My deal for a 455 fell through for my tempest clone so im on the search for a new motor.
ebay has a 67 ys short block and listing says its a california build not sure what california build means im a newbie

Thanks in advance
 

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GeeTee will probably chime in here as the California expert, but probably it means that it's from a car that actually had the A.I.R. pump installed and operating (as opposed to a 49-state car that had the A.I.R. passages in the heads but came with them plugged and no pump installed).

This is only significant if you plan to use those heads (probably casting number 670). If you're going to use other heads, it's a non-issue. Be aware that those 670's on a stock or overbored engine will result in a compression ratio that will be very marginal for pump gas, if that's your plan.
What are you going to build?

Bear
 

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Discussion Starter #3
Im just building a street car its a tempest that i bought with a good running cadillac 425in it.
I want to put a pontiac motor back in it.I have a 1975 complete 400 (185HP)with 6x heads i got for $200.Im trying figure what to do I want some power nothing crazy.I can get that 67 (335hp) shortblock for $800 sellers says it needs to be freshened up thats it.Do i or can i get that and put the 6x heads on it.Once again im new to this and really could use the advise

Thanks again
 

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What's the casting number on the 400 you already have? Passenger side rear of block, "below" the head, next to where the transmission bolts up, a string of 6 or so digits. While you're at it get the date code off the block (4 characters, top rear, near the distributor).

Bear
 

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Cast Jenuary 23, 1975 -- making it model year '75. 481988 - it's a good 2-bolt 400 and not a "557" 400 (which had less meat in the main webs).
Why buy another engine instead of building the one you have? It's a plenty good foundation for just about anything you'd want to do.

Bear
 

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Discussion Starter #7
Thats why im here.I certainly dont know too much on the engine end of this deal.I have been listening to a local engine guy who said to rebuild what i have.Then the other guy telling me his motor (67 shortblock)with the 6X heads from the 75 is the way to go and will save me $$$ because its going to take alot more $$$ to get the same hp out of the 75 motor.

Bear I appreciate your advice being new to this I dont want to get taken for a ride before I even get the car done. lol!
 

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Do you know if you have 6x-8 or 6x-4 heads? (See this link for how to tell)
6x Head ID

If they're -4's, you're actually in pretty good shape with what you have already.

Making power with an engine is all about air flow through it. And air flow is mostly determined by a combination of cylinder heads, intake ,exhaust, and cam. What you need out of a block and rotating assembly is really little more than being strong enough to stand up to the power level. Your guy with the 67 is either just trying to make a sale, or maybe he really doesn't know... that's ok either way because you've found a place here where there are people who do know a thing or two about building Pontiacs. :cheers

Are you interested in doing most of the work yourself, want someone to build it for you (without ripping you off), or somewhere in the middle? If you want a builder to do all/part of the work, my best recommendation is to contact Jim Lehart at Central Virginia Machine. Central Virginia Machine Service - Home of the Injun Engine!. He's a great source of information and a top notch builder who knows what he's doing, and he's honest.

A lot depends on "where you want to go" with it. Taking that 400 block you already have, it's very possible to come out the other side with an engine making well over 500 hp - depending on how deep your pockets are and what you want to do with the car. Even if you don't go that far with it, I strongly recommend running a good set of aftermarket forged rods in place of the factory rods. The rods are known to be the weak link in these engines once you start making some power with them, and given the small cost difference between buying a set of good rods outright and having the factory ones reconditioned, it's cheap insurance.
So... tell us more about what your goals are, how you're going to use the car, what kind of transmission you'll be using, what rear gear ratio you'll be running, do you care about having power brakes? etc. - and we'll get started playing "Blue Sky Pontiac Build" --- (one of my favorite games) :D

Bear
 

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Discussion Starter #9
looks like the they are 6x-8 heads

Im just looking to put together a nice street car that has some decent power nothing crazy just something fun to play with. the car has 400 trans and 3.55gears

I was told to look for 64 coded heads 87cc for the motor that i currently have
 

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Well, for good power there's no substitute for cubic inches (on a normally aspirated engine).

So, if it's not outside your budget I'd suggest doing something like this:
"stroker kit" consisting of a 4.25" stroke crank, forged rods, flat-top forged pistons
Your 6x-8 heads, prepped with good 7/16" screw in valve studs, fresh valve job, port matched to your intake.
block bored +.035 over (or whatever it takes to get good clean cylinders based on its current condition)
block zero-decked (this means shaving the top of the block as required to make the distance from the tops of the pistons to the top of the block exactly .000" - Pontiacs from the factory are usually around .020 "down")
All this will net you 461 cubic inches (or so, depending on how much overbore you need). If you add some thinner than stock head gaskets (.035 compressed thickness Cometic gaskets) you'll be at 9.2:1 compression with excellent quench characteristics -assuming your 6x-8 heads have the 'factory nominal' chamber sizes of 101 cc's (always measure Pontiac heads yourself because the do vary). Without going the stroker route, it'll be pretty much impossible to get your compression high enough on a 400 with those heads.

From there you pick a cam shaft and remainder of the valve train depending on what you want, your budget, and need for power brakes. I built my 461 using my numbers-matching 69 400 block, solid roller cam, ported Edelbrock aluminum heads. It's probably making somewhere around 520-550 hp on 93 octane and has run a best of 11.86 at 113 on the track. My cam though doesn't quite make enough vacuum to be reliable for power brakes (in my opinion, so I'm running a hydroboost brake system instead). The quench properties on my engine are now probably "fair" to "not so fair" (long story as to why).
When I broke it in on an engine dyno (with different heads than the Edelbrocks) it made just a hair's breadth under 500 hp, 540 lb. ft. of torque.
I'd recommend using reproduction "Ram Air" exhaust manifolds instead of headers. These manifolds won't make quite as much power as a good set of 4-tube headers, but what you'll save in headaches on installation/maintenance/etc. ought to more than make up for that on a street car. I'd run the factory cast iron intake manifold and a properly prepared QJet (everything port-matched to the heads, water crossover cut to separate it from the rest of the intake). On a low-rpm street cruiser that combination would be very hard to beat.

If you were to build a 461 with your existing block and heads, you'll spend "about" $1600 or so for the stroker kit (crank, rods, pistons, bearings), "about" $200 for the Cometic .035 head gaskets, "about" $800 for a good hydraulic flat-tappet cam and lifter kit. The rest would be whatever you spend on having the various components machined, gaskets/seals, and "extras" like missing parts/exhaust/ignition system/rocker arms/valve springs etc.

For all that, you'll have a reliable engine that will make boat-loads of torque at low rpm, peak horsepower probably somewhere around 400, peak torque probably somewhere around 460. It'll run great on 93 octane pump gas, make enough vacuum for power brakes, and be an absolute blast to drive. :D

How's that sound?

Bear

If you want to step it up from there, then you could go with a roller cam (a lot more expensive) ported aluminum heads (also $$$ if done right), "more" carb & intake, headers.... pretty soon you'd be making the same power as me, if not more.
 

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Call and talk to Jim at CVMS. That's where I got mine. He'll do as much or as little of the work as you want him to, and if you do decide on some massaged aluminum heads, Dave Wilcox there is one of the best. The Edelbrocks he ported for me are things of beauty.

Bear
 
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