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stllookn · 08-05-2004, 07:54 PM

1967 Stock engine performance:
250 155 hp @ 4200, 235 ft-lb @ 1600
292 170 hp @ 4000, 275 ft-lb @ 1600
283 175 hp @ 4400, 275 ft-lb @ 2400
327 220 hp @ 4400, 320 ft-lb @ 2800

Those are gross numbers, net are lower. The compression ratio on the 250 was 8.5, 292 - 8.0, 283 - 9.0 and 327 - 8.5. I used to hear guys bragging about their 283's getting 20 mpg. This must have been with taller gears and a stick in a sedan...not a truck.

Think about what happens to performance on that 292 when you bump the compression to 9.0 when you "freshen" it up. Nothing looks or sounds as cool as a V-8 but if it is an original restoration of a work truck stick with the I-6. The manual calls for a rebuild if the compression differential between the highest cylinder and the lowest exceeds 20%. Having said that...I drove my my 292 I-6 for over 300 miles with only 5 pistons...SERIOUSLY...I had to pull one when it swallowed a valve! I drove it home and it shook like you would not believe...but it ran!

08-05-2004, 07:54 PM	#7
stllookn Saving 1 truck at a time! Join Date: Aug 2001 Location: Kent, WA Posts: 6,465	1967 Stock engine performance: 250 155 hp @ 4200, 235 ft-lb @ 1600 292 170 hp @ 4000, 275 ft-lb @ 1600 283 175 hp @ 4400, 275 ft-lb @ 2400 327 220 hp @ 4400, 320 ft-lb @ 2800 Those are gross numbers, net are lower. The compression ratio on the 250 was 8.5, 292 - 8.0, 283 - 9.0 and 327 - 8.5. I used to hear guys bragging about their 283's getting 20 mpg. This must have been with taller gears and a stick in a sedan...not a truck. Think about what happens to performance on that 292 when you bump the compression to 9.0 when you "freshen" it up. Nothing looks or sounds as cool as a V-8 but if it is an original restoration of a work truck stick with the I-6. The manual calls for a rebuild if the compression differential between the highest cylinder and the lowest exceeds 20%. Having said that...I drove my my 292 I-6 for over 300 miles with only 5 pistons...SERIOUSLY...I had to pull one when it swallowed a valve! I drove it home and it shook like you would not believe...but it ran! __________________ '68 C20 Longhorn 50th Anniversary 400/TH400 '68 C20 Longhorn 50th Anniversary 468/TH400w/buckets '72 C20 Halfhorn (Longhorn w/o cab and front clip) '69 Flxible Cruiser (look up ugly in the dictionary) Last edited by stllookn; 08-05-2004 at 08:16 PM.