Have you got a HP number you want, or do you have an ET goal. You just want a good solid street engine?
Tore into my 468 tonight
3
i recently picked up this motor to drop in my 71, the guy didn't know anything about the build up of it other than he claims its 10.0:1 or about. Since I am the way I am I decided to tear it down and figure out exactly what I have (well to the best of mine and your knowledge put together) so heres what I see.
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pulled the heads to see whats sitting under here, I know its .060 over (stamped on the piston heads) but not sure if these pistons and my 781 heads will have the CR he was calculating. The deck is original since I can still see the stampings on the passenger side of the block. The cross-hatching is still present in the cylinders ever so slightly yet.
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happy when I pulled off the heads to see that its already loaded with the 2.25 and 1.88 valves. The intake valves are necked down but I am not sure if they are extended length valves or not. I have no idea of the springs as I dont have anything to test the pressure of them with.
now the camshaft. I did the calculations and measured them from the valley, odd to me is that the exhaust is larger lift than the intake??? I measured around .347 (.589) exhaust and around .335 (.569) intake. Now I say around since I had it setup rather sloppy but I get around the same numbers each time I spin it.
The guy I got it from said it had plenty of power to burn the tires off the chevelle it came out of, but I need some advice if I should swap out for better pistons and larger camshaft. I have a edelbrock RPM air gap intake, and a holley 4781 850dp (with drilled butterflies). I want to do mostly street with some strip time. Car is 4speed muncie, 12 bolt rear with low 3.08gears for now, I wanted to go up to the mid 3.5 range but this is what I have for now. I am really on the idea of switching to E85 and having the carb modified or finding another one to have the switch made. That decision hasn't been finalized but its more than likely the route I am taking.
Let me know what you guys think about what I have and what I should/could purchase.
pulled the heads to see whats sitting under here, I know its .060 over (stamped on the piston heads) but not sure if these pistons and my 781 heads will have the CR he was calculating. The deck is original since I can still see the stampings on the passenger side of the block. The cross-hatching is still present in the cylinders ever so slightly yet.
happy when I pulled off the heads to see that its already loaded with the 2.25 and 1.88 valves. The intake valves are necked down but I am not sure if they are extended length valves or not. I have no idea of the springs as I dont have anything to test the pressure of them with.
now the camshaft. I did the calculations and measured them from the valley, odd to me is that the exhaust is larger lift than the intake??? I measured around .347 (.589) exhaust and around .335 (.569) intake. Now I say around since I had it setup rather sloppy but I get around the same numbers each time I spin it.
The guy I got it from said it had plenty of power to burn the tires off the chevelle it came out of, but I need some advice if I should swap out for better pistons and larger camshaft. I have a edelbrock RPM air gap intake, and a holley 4781 850dp (with drilled butterflies). I want to do mostly street with some strip time. Car is 4speed muncie, 12 bolt rear with low 3.08gears for now, I wanted to go up to the mid 3.5 range but this is what I have for now. I am really on the idea of switching to E85 and having the carb modified or finding another one to have the switch made. That decision hasn't been finalized but its more than likely the route I am taking.
Let me know what you guys think about what I have and what I should/could purchase.
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It should look more like this
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I didn't take time to google it, but let's assume the previous answer of '73-'85 454 car or truck block is correct. Given that info, the block isn't going to be anything particularly special, unless it's from a '73 or '74 Corvette. Even then, it's not going to be particularly special in terms of its performance, but it may be worth a little more if you can find the original Corvette to put it back into.
Bottom line: just build what you want with it!
Yours? Nice!It should look more like this
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"my goal has been raised to ~550hp+." Ah mission creep begins!
Fun pulling apart the engine to see what is uncovered...
How much more is a 496 stroke crank? If you need new pistons anyway...going up another 40 cubes seems like money well spent.
I built my 400 with pretty good parts inside, but little did I know I would have swapped two sets of heads and on my 4th cam in the same shortblock in 7 years. Glad I built the low end strong for 'easy' topend upgrades down the road.
Nice shot with the Nova in the background...
Fun pulling apart the engine to see what is uncovered...
How much more is a 496 stroke crank? If you need new pistons anyway...going up another 40 cubes seems like money well spent.
I built my 400 with pretty good parts inside, but little did I know I would have swapped two sets of heads and on my 4th cam in the same shortblock in 7 years. Glad I built the low end strong for 'easy' topend upgrades down the road.
Nice shot with the Nova in the background...
If you can't afford to put a good aluminum head on it now, I would save and plan on a head change when I could. Just my two cents. Go for 600 hp, the more the merrier.
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