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#1
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headers size for 68 Firebird
What size headers would be required to support a 750 hp engine? Round port.
Looking at a set of Doug's 1-7/8" for a 68 Firebird. Also wondering if they will fit a 68 Firebird? Thanks |
#2
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#3
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Quote:
Meaning, if the cam is not correctly spec'd would larger headers add more power. |
#4
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Hi John..... No, I don't think so.
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#5
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I believe 1 7/8 would work fine. I used a set of Doug's recently and had to clearance them on the idler arm and power steering box . These were round ports. The mad dog headers fit well I hear if you can get a set.
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Be carefull of the feet you step on today.They may be attached to the a$$ you kiss tomorrow. |
#6
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Posted for conversation...
https://www.motortrend.com/how-to/he...s-performance/ Note on the graph it states "inside" diameter. Take note of the tubing used on the headers involved, are they based on a popular 16 gauge or 18 gauge materiel. Example if 16 gauge: .062" thick x 2 sides = 0.124" .
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE |
#7
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I use 2" tubes on my car at around 700 Hp.
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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
#8
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Handy chart.
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
#9
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The handy chart above, again based on the inside diameter.
.
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE |
#10
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We tried some 1 3/4-1 7/8 step-real short 1 3/4 section and about as big as port on a friend's 650 HP 462 E head roller motor and lost 40 HP and a lot of TQ vs the 2" he had. Used some modified GTO Hookers to fit his 63 Tempest.
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Skip Fix 1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever! 1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand 1965 GTO 4 barrel 3 speed project 2004 GTO Pulse Red stock motor computer tune 13.43@103.4 1964 Impala SS 409/470ci 600 HP stroker project 1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs |
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