300 hp VS 340 hp
03-11-2009, 11:41 AM
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300 hp VS 340 hp
Does anyone know what made the difference between the 300, and 340 HP Corvette engines in 62. Was it just the intake manifold, and cam ?
03-11-2009, 11:58 AM
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about 40 horses ???
cam, intake, compression, and I think head valve size...not sure about that, though
the heads may have been the change in compression, small cc....
Someone much smarter than me will give a more definate answer
cam, intake, compression, and I think head valve size...not sure about that, though
the heads may have been the change in compression, small cc....
Someone much smarter than me will give a more definate answer
Last edited by Donny Brass; 03-11-2009 at 12:00 PM.
03-11-2009, 12:46 PM
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The 300s and 340s had the same heads, same valve sizes (1.94/1.5).
The 300 had an iron intake.
The 340 had an alum intake.
Both had an AFB carb.
The 300 had flat top pistons.
The 340 had domed pistons.
The 300 had a hyd cam/lifters.
The 340 had a solid cam/lifters (097 cam).
The 300 had stamped steel valve covers.
The 340 had finned alum valve covers.
The 300 had a vac adv, single point distributor.
The 340 had a mechanical adv dual point distributor.
The 340 had the big, 8in diameter finned harmonic balancer.
Tom Parsons
The 300 had an iron intake.
The 340 had an alum intake.
Both had an AFB carb.
The 300 had flat top pistons.
The 340 had domed pistons.
The 300 had a hyd cam/lifters.
The 340 had a solid cam/lifters (097 cam).
The 300 had stamped steel valve covers.
The 340 had finned alum valve covers.
The 300 had a vac adv, single point distributor.
The 340 had a mechanical adv dual point distributor.
The 340 had the big, 8in diameter finned harmonic balancer.
Tom Parsons
03-11-2009, 01:01 PM
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The 340's had swirled polished intake valves, the 300's didn't.
The 340's had push rods with hardened tips, the 300's didn't.
the 340's used hardened cranks journals, the 300's didn't. Don't remember about the crank bearings but I think they were different.
I think the rockers were hardened on the 340 and not on the 300 but I'm not sure.
The clutch was different.
Generator pulley was different I believe.
The 340's had push rods with hardened tips, the 300's didn't.
the 340's used hardened cranks journals, the 300's didn't. Don't remember about the crank bearings but I think they were different.
I think the rockers were hardened on the 340 and not on the 300 but I'm not sure.
The clutch was different.
Generator pulley was different I believe.
03-11-2009, 01:14 PM
#5
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The 300s and 340s had the same heads, same valve sizes (1.94/1.5).
The 300 had an iron intake.
The 340 had an alum intake.
Both had an AFB carb.
The 300 had flat top pistons.
The 340 had domed pistons.
The 300 had a hyd cam/lifters.
The 340 had a solid cam/lifters (097 cam).
The 300 had stamped steel valve covers.
The 340 had finned alum valve covers.
The 300 had a vac adv, single point distributor.
The 340 had a mechanical adv dual point distributor.
The 340 had the big, 8in diameter finned harmonic balancer.
Tom Parsons
The 300 had an iron intake.
The 340 had an alum intake.
Both had an AFB carb.
The 300 had flat top pistons.
The 340 had domed pistons.
The 300 had a hyd cam/lifters.
The 340 had a solid cam/lifters (097 cam).
The 300 had stamped steel valve covers.
The 340 had finned alum valve covers.
The 300 had a vac adv, single point distributor.
The 340 had a mechanical adv dual point distributor.
The 340 had the big, 8in diameter finned harmonic balancer.
Tom Parsons
The 340's had swirled polished intake valves, the 300's didn't.
The 340's had push rods with hardened tips, the 300's didn't.
the 340's used hardened cranks journals, the 300's didn't. Don't remember about the crank bearings but I think they were different.
I think the rockers were hardened on the 340 and not on the 300 but I'm not sure.
The clutch was different.
Generator pulley was different I believe.
The 340's had push rods with hardened tips, the 300's didn't.
the 340's used hardened cranks journals, the 300's didn't. Don't remember about the crank bearings but I think they were different.
I think the rockers were hardened on the 340 and not on the 300 but I'm not sure.
The clutch was different.
Generator pulley was different I believe.
03-11-2009, 01:27 PM
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03-11-2009, 03:30 PM
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The 340 HP engine has to be one of the nicest SB Chevrolet engines of all time. Such great mid range torque and the throttle response was just outstanding. My first solo in a Corvette was a 340 hp '62 when I was sixteen. This one had 4.11 gears and that thing ran like a raped ape. Can remember like it was yesterday (1965). Adjusted for age, it had to be one of my top ten experiences of all time (I live a sheltered life).
03-11-2009, 04:00 PM
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03-11-2009, 04:21 PM
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03-11-2009, 04:31 PM
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Yup. Casting number was the same (3782461) but the '64 sported the 2.02s. A hot item in the mid 60s. Every SB owner wanted a set of those.
03-11-2009, 04:57 PM
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03-11-2009, 08:18 PM
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03-11-2009, 08:58 PM
#13
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The 340's had swirled polished intake valves, the 300's didn't.
The 340's had push rods with hardened tips, the 300's didn't.
the 340's used hardened cranks journals, the 300's didn't. Don't remember about the crank bearings but I think they were different.
I think the rockers were hardened on the 340 and not on the 300 but I'm not sure.
The clutch was different.
Generator pulley was different I believe.
The 340's had push rods with hardened tips, the 300's didn't.
the 340's used hardened cranks journals, the 300's didn't. Don't remember about the crank bearings but I think they were different.
I think the rockers were hardened on the 340 and not on the 300 but I'm not sure.
The clutch was different.
Generator pulley was different I believe.
03-11-2009, 09:03 PM
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03-11-2009, 10:01 PM
#16
Le Mans Master
The 340 HP engine has to be one of the nicest SB Chevrolet engines of all time. Such great mid range torque and the throttle response was just outstanding. My first solo in a Corvette was a 340 hp '62 when I was sixteen. This one had 4.11 gears and that thing ran like a raped ape. Can remember like it was yesterday (1965). Adjusted for age, it had to be one of my top ten experiences of all time (I live a sheltered life).
My first Corvette was a '63 327/340, 4:11 gears, close ratio 4-speed, two-top convertible . . . .
Sweet Dreams
03-11-2009, 10:14 PM
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I used to save stuff like this. Throw it in coffee cans. The last SHP engine I built up a few years ago, I pulled some of these used rockers out of the can, cleaned them up and used them.l
There was also some rockers that had a small oval stamped on them. I always thought that started in '65 on the SHP engines. Not sure. Too much water over the dam.
03-11-2009, 10:34 PM
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I used to save stuff like this. Throw it in coffee cans. The last SHP engine I built up a few years ago, I pulled some of these used rockers out of the can, cleaned them up and used them.l
There was also some rockers that had a small oval stamped on them. I always thought that started in '65 on the SHP engines. Not sure. Too much water over the dam.
There was also some rockers that had a small oval stamped on them. I always thought that started in '65 on the SHP engines. Not sure. Too much water over the dam.
These are (were) the SPHP rocker arms---------------now long discontinued.
Tom Parsons
03-12-2009, 08:58 AM
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