Topic: What's the difference between 300hp and 350hp?
in Forum: C3 Engines
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Just wondering what the difference is between the 2 350 engines (1969). I know the cams are different, are there any other differences?
Thanks,
Matt
Thanks,
Matt
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Frederick, MD - USA
Joined: 9/8/2003
Posts: 3398
Vette(s): 1969 convertible L71 427/435 4-speed black interior
According to the Corvette Black Book, the two 350 engines use different casting cylinder heads, different model Q-Jet, and different part number distributors. It doesn't mention the cam, but it's a good bet it would be different to go with the different heads and carb.
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COLUMBUS, MS - USA
Joined: 1/11/2004
Posts: 331
Vette(s): 1972 Coupe; 350 4-speed with GM sidepipes;
Classic White/Saddle
According to Corvette By The Numbers, both used the same crank as well as the same intake and exhaust manifolds. Three different blocks were used, but all were used in 300hp and 350hp applications. All three are 4-bolt blocks. 
Cylinder head #3927187 was used on the 350hp only.
Three different distributors were used:
1111490 = 350/300hp
1111491 = 350/350hp
1111493 = 350/350hp
The two cams were #3896930 (300hp) and # 3896963 (350hp).
Check the stamp pad. 300hp motors carry suffix "HY" or "HZ". 350hp motors carry the "GD", "HW" or "HX" suffix.
Add all this to Gunslinger's data.
John
|UPDATED|5/16/2004 5:54:51 PM (AZT)|/UPDATED|
Cylinder head #3927187 was used on the 350hp only.
Three different distributors were used:
1111490 = 350/300hp
1111491 = 350/350hp
1111493 = 350/350hp
The two cams were #3896930 (300hp) and # 3896963 (350hp).
Check the stamp pad. 300hp motors carry suffix "HY" or "HZ". 350hp motors carry the "GD", "HW" or "HX" suffix.
Add all this to Gunslinger's data.
John
|UPDATED|5/16/2004 5:54:51 PM (AZT)|/UPDATED|
I hate to do this. I just can't help myself. I'm sorry.
What's the difference between 300 HP and 350 HP?
50 HP.
Okay, let me have it. I deserve it.
What's the difference between 300 HP and 350 HP?
50 HP.
Okay, let me have it. I deserve it.
Lifetime MemberSHELBYVILLE, TN - USA
Joined: 7/5/2002
Posts: 3942
Vette(s): 1976 L48 auto
1978 L82 4speed
1994 LT1 6speed
1978 L82 4speed
1994 LT1 6speed
the 300 hp had 10.2 comprestion the 350hp. had 11.1 avey| 
the 300hp @4800&350 @5600 rpm
|UPDATED|5/17/2004 3:25:15 PM (AZT)|/UPDATED|
the 300hp @4800&350 @5600 rpm|UPDATED|5/17/2004 3:25:15 PM (AZT)|/UPDATED|
StingrayJim 
NCM Lifetime Member #1936
Stingray's '76���������������������������� StingrayJr's '78���������������������������Lil Red '94 
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Lifetime MemberHot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
the cam was fairly different
if you look at the torque, they both produced 380 lbs but the 300 was at a much lower RPM..
if you look at the torque, they both produced 380 lbs but the 300 was at a much lower RPM..
in Forum: C3 Engines
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