but yeah wouldn't expect too much one of my friends had one and i really wasn't impressed. in a small car like that it'd be fun. 
Sorry. 
400 small block
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400 small block I'm not new to the car game but I am new to GM stuff. I thinking about buying an 80' Monza with a 400 small block and I was just wondering how much power you think the motor should be making? It came out of a 71 Impala, has a stock rebuild with a performer intake and carb, stock exhaust manifolds and the big valve iron heads. pretty much a very mildly modified 400
you guys are being way too optimistic even coming close to saying 300hp. that intake isn't any better than what came off of it except it isn't as heavy. I'd go on the high side of 225 because of the manifolds. And as for big valve heads, they probably aren't 2.02's unless he's got some sort of proof or can show you the casting numbers. Thats still pleny of power to shove that little car around and w/ some tweaking could put you in the 13's.
1st rule of learning GM is guys w/ old stuff think that 68-72 was the golden age of performance and only remember the guys that were fast and not the actual numbers, so don't get caught up in trying to hunt down old stuff.
Still sounds like a decent project.
1st rule of learning GM is guys w/ old stuff think that 68-72 was the golden age of performance and only remember the guys that were fast and not the actual numbers, so don't get caught up in trying to hunt down old stuff.
Still sounds like a decent project.
Teching In
Joined: Jan 2009
Posts: 20
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From: SPRING
i have to agree with bigbad on this one, the 400 was never really a factory hp motor stock.now with some mods on it and the right cam it should do very well in the little car, i have a 400 in a luv and it puts out less than 400 but scoots down the track very well.
Teching In
Joined: Jan 2009
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From: Oxford, Alabama
The 400 small blocks were detuned highly by the factory. What you have is a great performance platform though. If you have some spare cash, this is a budget build that would make that little car a beast. http://www.chevyhiperformance.com/te...que/index.html
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Your probably lucky to make 250-275 as it sits. Now, with a good set of heads, the right cam, better exhaust, you could be over 400 hp easily. I've got a 505 hp 406 in my 67 Camaro and it made that much power on the dyno at 5200 rpm with pump gas, and a hydraulic flat tappet cam. Made over 500 ft lbs of torque too. The car definately goes down the road now.
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the 400 was mainly in trucks and big body cars where torque was a priorty, not horsepower. if building it, i would definitely change rods, heads, pistons, and at least a performer rpm intake but preferrably a vic. jr. like stated above it's a good platform to start with but needs some improvements.
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Yeah, I was thinking somehwere around 250HP or so. All I want is a nice mid to low 13 second ride. How close do you think it would be to that goal with a nice cam and some headers? Anyone on here ever spray a small shot on a stock 400 before?
Staging Lane
Joined: Jan 2009
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I raced a luv on street tires and it was a 400 with iron heads and a very very mild cam and a carb and it went down and 12.8 with no traction
WHO cares about hp. The hp is probably in the 250-275 hp range but the torque is above 350 for sure. Torque equals acceleration and hp is calculate off of that due to rpms. These motors were made for torque because of the longer stroke so she will have alot of get up and go but because its going to be right there at the bottom and have no steep gains really it wont be as fun to drive because it wont feel as fast.
if you do a head swap, intake and carb and new cam for a couple grand you will wake her up a 400 block now a-days is 100% worth it if its a good block because you can really stroke those things becasue of the extra bore size on a sbc.
if you do a head swap, intake and carb and new cam for a couple grand you will wake her up a 400 block now a-days is 100% worth it if its a good block because you can really stroke those things becasue of the extra bore size on a sbc.
Last edited by Radcannon; Feb 1, 2009 at 11:09 PM.
