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<blockquote data-quote="swampratt" data-source="post: 3103054" data-attributes="member: 15054"><p>I assumed again that most people or guys have dreams of going fast since they were tens and were in the loop as to what is what.</p><p>Reading all the car mags they could get their hands on. But it is not so.</p><p><a href="https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=268H" target="_blank">https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=268H</a></p><p>That link is for many offshoots of the 268H.</p><p>The 268H is a part number or short description of a Competition Cams camshaft.</p><p>It came out in the late 70's to early 80's along with other cams in that high energy line and magnum line.</p><p>Harold Brookshire designed that 268H as his answer to the 350HP 350 camshaft.</p><p>His idea was it would make as much or more power than the GM cam and have better manners and MPG all around and he nailed it.</p><p></p><p>Harold worked with/at Ultradyne cams and made some really great grinds and he worked at Comp Cams and Lunati Cams.</p><p>His design was the VooDoo line of cams.</p><p>Just a lot of UD harold grinds out there.</p><p></p><p>GM made a 302 as did Ford.. when I speak of 302 I will usually talk of my Ford.</p><p>305" heads from a GM vehicle will have a smaller chamber than a 350 head the reason to run them is to get that smaller chamber to raise compression.</p><p>If you know how to match and massage parts you can run a lot of compression with pump gas. say 91 octane.</p><p></p><p>Say we were stuck with the 76 CC (Cubic centimeters) head from a 350 That means the chamber will hold 76cc of liquid.</p><p></p><p>The bore is 4.00 on a 350 and the stroke is 3.48 and the piston is .025" below the top of the block (Deck)</p><p>You run a head gasket that is .039" thick and the vlave releifs on the piston are 5.5cc.</p><p></p><p>Your compression ratio would be 8.5 :1 You can easily run 9.5 with 87 or 89 octane.</p><p>Mill the 76cc head .030 and get 72 cc chamber and be at 8.82 compression.</p><p>Run the GM vortec heads which came out in 1996 with their 64 cc chamber and have you get 9.57: 1 compression.</p><p></p><p>You can run a smallish cam with that and make great power.</p><p></p><p>I like more power more low end TQ more top end power so I go with an even smaller chamber and I then port the head to up the airflow of it.</p><p>I have taken the 64cc head and milled it to 54cc.</p><p>With the above that would put you at 10.73 :1 compression..You better have your ducks in a row to make that work.</p><p></p><p>I went even farther and decked the block to get the pistons closer to the top of the block .013" and ran an even thinner head gasket .015".. border line psycho for pump gas at an actual compression of 11.95:1</p><p></p><p>It worked very well.</p><p>But I started young and my first car could not muster 20 seconds in the 1/4 and tune tune tune I did and started with that kind of junk and eventually went mid 11's in the 1/4 on pump gas with no power adders.</p><p></p><p>Learning the hard way what does and does not work and learning how to tune every last ounce of power from what you have at hand..and I was on a tight budget with 3 kids and a wife.</p><p></p><p>Confused even more?</p></blockquote><p></p>
[QUOTE="swampratt, post: 3103054, member: 15054"] I assumed again that most people or guys have dreams of going fast since they were tens and were in the loop as to what is what. Reading all the car mags they could get their hands on. But it is not so. [URL]https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=268H[/URL] That link is for many offshoots of the 268H. The 268H is a part number or short description of a Competition Cams camshaft. It came out in the late 70's to early 80's along with other cams in that high energy line and magnum line. Harold Brookshire designed that 268H as his answer to the 350HP 350 camshaft. His idea was it would make as much or more power than the GM cam and have better manners and MPG all around and he nailed it. Harold worked with/at Ultradyne cams and made some really great grinds and he worked at Comp Cams and Lunati Cams. His design was the VooDoo line of cams. Just a lot of UD harold grinds out there. GM made a 302 as did Ford.. when I speak of 302 I will usually talk of my Ford. 305" heads from a GM vehicle will have a smaller chamber than a 350 head the reason to run them is to get that smaller chamber to raise compression. If you know how to match and massage parts you can run a lot of compression with pump gas. say 91 octane. Say we were stuck with the 76 CC (Cubic centimeters) head from a 350 That means the chamber will hold 76cc of liquid. The bore is 4.00 on a 350 and the stroke is 3.48 and the piston is .025" below the top of the block (Deck) You run a head gasket that is .039" thick and the vlave releifs on the piston are 5.5cc. Your compression ratio would be 8.5 :1 You can easily run 9.5 with 87 or 89 octane. Mill the 76cc head .030 and get 72 cc chamber and be at 8.82 compression. Run the GM vortec heads which came out in 1996 with their 64 cc chamber and have you get 9.57: 1 compression. You can run a smallish cam with that and make great power. I like more power more low end TQ more top end power so I go with an even smaller chamber and I then port the head to up the airflow of it. I have taken the 64cc head and milled it to 54cc. With the above that would put you at 10.73 :1 compression..You better have your ducks in a row to make that work. I went even farther and decked the block to get the pistons closer to the top of the block .013" and ran an even thinner head gasket .015".. border line psycho for pump gas at an actual compression of 11.95:1 It worked very well. But I started young and my first car could not muster 20 seconds in the 1/4 and tune tune tune I did and started with that kind of junk and eventually went mid 11's in the 1/4 on pump gas with no power adders. Learning the hard way what does and does not work and learning how to tune every last ounce of power from what you have at hand..and I was on a tight budget with 3 kids and a wife. Confused even more? [/QUOTE]
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