Blew the 400 up

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Deadman walking

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Well I blew my 400 small block up. oil pump went out on the interstate and spun a bearing so I picked up this 116k vortec block. I guess it's just a mexico made block but not bad for 500.
 

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Deadman walking

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Update. so I'm gonna pull my cam and noisy gear drive and throttle body off the 400. carb intake to TBI adapter and vortec heads machined and springs beefed up for 480/480 cam. And eventually I'll just throw a q junk on there that I bought from eBay.

What should I be aware of when doing this swap?
 

L31MaxExpress

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Update. so I'm gonna pull my cam and noisy gear drive and throttle body off the 400. carb intake to TBI adapter and vortec heads machined and springs beefed up for 480/480 cam. And eventually I'll just throw a q junk on there that I bought from eBay.

What should I be aware of when doing this swap?
Leave the noisy gear drive hanging on the wall as wall art. Harmonics will shorten the life of everything connected to them.
 

Deadman walking

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I'd have pulled the 400 apart, see how bad it is inside, and maybe fix that, rather than dropping $500 on a Vortec engine




I thought about it but I decided against it new crank bearings and crank or to have it turned would've costed 500 alone. I think it was worth it considering the milage
 

Schurkey

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Diesels tend to run at significantly lower RPM, and with lower valve spring pressures. The gears are also engineered to be durable, instead of being designed specifically to make noise and impress children.

Some aftermarket gear drives can be acceptable in some forms of racing; but those gear drives again have some "real" engineering, rather than the "slap this on, it sounds just like a blower" "engineering".

It's exactly like axle ring-and-pinion gears. If the gearset is noisy, the gears are not meshing properly. And this is INTENTIONAL on bottom-feeder gear drives.
 

L31MaxExpress

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What does that statement even mean?
A gear drive isn't inherently bad for a motor, they're used in many diesels.
It means that they create vibration from the poor meshing as well as allow harmonics to transfer between the valve train and crankshaft. All of which cause additional bearing wear.
 

Hipster

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What does that statement even mean?
A gear drive isn't inherently bad for a motor, they're used in many diesels.
Higher end gear drives have a fixed single idler gear and are inherently a better more accurate set-up than the low end linked, floating, dual idler gear set-ups.
 
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Hipster

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Diesels tend to run at significantly lower RPM, and with lower valve spring pressures. The gears are also engineered to be durable, instead of being designed specifically to make noise and impress children.

Some aftermarket gear drives can be acceptable in some forms of racing; but those gear drives again have some "real" engineering, rather than the "slap this on, it sounds just like a blower" "engineering".

It's exactly like axle ring-and-pinion gears. If the gearset is noisy, the gears are not meshing properly. And this is INTENTIONAL on bottom-feeder gear drives.
Used to deal with stuff a lot or motorcycle engines where the cam was gear driven off the crank. You have guage pins to measure gear diameters in between the teeth for cam and crank gears and options on different size gears for the crank to get it right. Too loose sounded clunky, too tight whined, just rite was near silent. Get it wrong and it explodes the case in short order. I could see these floating gear types really wrecking some stuff.
 
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