Header design
| Line 16: | Line 16: | ||
Another thought - equal primary tube length. If the length of the primary is part of the tuning equation, how well does an engine run with different primary tube lengths? Try and jet that carburetor without pulling your hair out! Most of the commercially availble headers out there have a large variance in tube length. Check out a set for a big block mopar in a B or E body for an example. I have measured a 16" variance from longest to shortest tube on these units. | Another thought - equal primary tube length. If the length of the primary is part of the tuning equation, how well does an engine run with different primary tube lengths? Try and jet that carburetor without pulling your hair out! Most of the commercially availble headers out there have a large variance in tube length. Check out a set for a big block mopar in a B or E body for an example. I have measured a 16" variance from longest to shortest tube on these units. | ||
| + | |||
| + | Check out this pair of Big Block Chevy Headers | ||
| + | |||
| + | [[Image:unequal.jpg]] | ||
| + | |||
| + | the driver's side rear tube (in yellow) must be about 10"-12" shorter than the next tube (in red). | ||
| + | |||
| + | I guess all we can do is create our headers properly or reconfigure existing units to work as they should and not give ourselves tuning headaches. | ||
This would mean that the shortest primary tube would not create a scavenge for that cylinder, so that cylinder would not make the same power as the others, and would require different jetting and timing than the others as well. How do you do that with a standard kettering distrubutor and an simple carburetor? | This would mean that the shortest primary tube would not create a scavenge for that cylinder, so that cylinder would not make the same power as the others, and would require different jetting and timing than the others as well. How do you do that with a standard kettering distrubutor and an simple carburetor? | ||
Your Privacy Choices