Needs MORE POWER!!! (Tim Taylor Style!!!)

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Chevy 88

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Are you sure the 400 is above stock? I don't believe they were big power makers in stock form.



Based on the truck, and the opinions of the old school mechanics that have looked at it, I'm pretty sure it has at least a cam.

Plus it pulls pretty hard, even with the 37's.
 

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Old school is throwing a handful of mothballs in your gas tank!
 

xm20k

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In stock form a 400 made a whopping 150-265HP year and application dependent. With a bit of a cam probably a towing or RV cam all else stock 2-300 depending on which piston type and or head was used. The right way to make more power is to rebuild it put in a set of flat top pistons, 64 cc chamber heads and a decent cam.
 

Chevy 88

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In stock form a 400 made a whopping 150-265HP year and application dependent. With a bit of a cam probably a towing or RV cam all else stock 2-300 depending on which piston type and or head was used. The right way to make more power is to rebuild it put in a set of flat top pistons, 64 cc chamber heads and a decent cam.

How do I determine if I have this stuff already? Bore scope in the spark plug hole?

Head numbers?

Cam?
 

xm20k

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Casting numbers off of both block and heads google the numbers will give you specs like year of block 2 or 4 bolt etc. same with head casting number should give year range chamber size, valve size etc. as for cam if it isnt stock only way to find out is to pull it and check numbers on the end.
 

Chevy 88

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Casting numbers off of both block and heads google the numbers will give you specs like year of block 2 or 4 bolt etc. same with head casting number should give year range chamber size, valve size etc. as for cam if it isnt stock only way to find out is to pull it and check numbers on the end.



Where would these number be?
 

xm20k

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Casting number for block should be behind the driver side head on the top of the flange were the trans bolts up. The head numbers are on the top of the heads under the valve cover between the rockers.

Here are the numbers one for heads one for blocks
 

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The valve covers are easy enough to remove. They are chrome with those hand twist of things. No tools required. If I got the block number and a head number, would you be willing to decipher the hieroglyphs for me? It would be kinda nice to know what it all is.
 

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How do I determine if I have this stuff already? Bore scope in the spark plug hole?

Head numbers?

Cam?
Take it to LesScwab and they can tell you. They are geniuses and work for free.Or get the engine code off the front of the block,behind the alternator stamped on a rectangular pad. Get the head numbers from underneath the valve covers. To spec the cam,degree the balancer or put on a degree wheel pull 1 exhaust rocker,1 intake rocker turn the engine over and watch your degree wheel and use a dial indicator to spec your cam at the pushrod. Back yard dirty method roll the engine over holding the tip of a pushrod feel when the pushrod parks,lay a 3x5 index card on the head and against the pushrod and mark it,roll it until it parks at bottom,mark it again. Measure between the 2 marks multiply by 1.5. That only gets you lift though. If we are seeing number over .425 it's got a mystery cam. For your marks thinknof mom and dad marking your height on a piece of door trim,seeing how tall you were at 10 and 12 he grew 2 inches in 2 years. My pushrod moves .35 from bottom to top.
 
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Chevy 88

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Numbas
 

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Ricko1966

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882 low compression smog heads. I don't use block numbers not enough info from a block number all that tells me is it's a 400 block. The number behind the alternator tells year,compression,2bbl,4bbl,auto, manual,hp
 
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Chevy 88

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If the block was machined, could that obliterate the numbers behind the alternator?
 

Ricko1966

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If the block was machined, could that obliterate the numbers behind the alternator?
Yes it could did you look fir the numbers? Did you find thr pad where the numbers are stamped? The pad should still be there.
 

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