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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: bob77 on August 25, 2008, 01:53:02 pm

Title: 250-6
Post by: bob77 on August 25, 2008, 01:53:02 pm
I have two shortbox chevys. One 77 and one 78. Both have the 250-6. The 77 has the integral head and intake while the 78 has seperate head and intake. I had an 80 that had the integral head and intake. I haven't checked the numbers on the engine but I am suspicious that the 250 in the 78 is not original. Does anyone know if they put the seperate head/intake setup in a 78 or if they used both setups in the same years at all? I really don't care for the integral head/intake. I am planning on getting rid of the 78 but I am wondering if it is worth it to keep the engine. Any opinions on the head/intake setups for these 250's?
Title: Re: 250-6
Post by: Captkaos on August 25, 2008, 02:26:33 pm
The integrated head for the 250 I6 started in 1975, they didn't offer non-integrated heads after that.  The only I6 that did come with a non-integrated head during the run was the 292..
Title: Re: 250-6
Post by: bob77 on August 25, 2008, 02:36:41 pm
Interesting. That would definitely mean that the 78 I have has a non-original 250. I'll have to pull the numbers from the motor and check it out.
Title: Re: 250-6
Post by: Layne on August 25, 2008, 08:48:56 pm
I have an I6 and am not sure what the difference is. Would somebody have a pic?
Title: Re: 250-6
Post by: Lt.Del on August 25, 2008, 08:57:13 pm
Layne, I have never owned a Chevy inline 6, but I think by integrated (i could be wrong), it is like my old 68 mustang 250 6 cylinder where the intake and cylinder head are one in the same, cannot separate.  Ford had the 170, 200 and 250 ci inline sixes for Mavericks and Stangs, and 300 ci for trucks/vans.  Those puppies would fly with their torque and very fuel efficient.

These are old pics, when I was 15 and rebuilding my first engine (yes they had invented color pictures by then), my 68 stang.  It shows how the inline 6 had the intake and head as the same piece.
(http://www.delbridge.net/og.jpg)(http://www.delbridge.net/68me.jpg)
Title: Re: 250-6
Post by: Captkaos on August 25, 2008, 09:33:49 pm
Layne,
The integrated head has the cylinder head and intake cast as one piece.
Title: Re: 250-6
Post by: bob77 on August 25, 2008, 11:06:37 pm
Yeah. The disadvantage is that you obviously cannot change out the intake without changing to a different head as well. The advantage... You'll never have a leaky manifold gasket. I have mixed opinions. I think I will be sticking with my integrated setup for awhile.
Title: Re: 250-6
Post by: Layne on September 03, 2008, 07:18:43 pm
Sweet. thanks guys. so I have the non integrated head. I bet gm made some money on bad heads as they had to replace the intake as well!!! Lol