best intake manifold for 625 street demon?
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best intake manifold for 625 street demon?
TL : DR whats a good intake manifold for a Street demon 625
Hey guys! i usually come here when i need some advise as most of us do, and today is no exception. I have an 85 Firebird with a 305 (from what i know is stock) with a manual 5 speed (sorry, i do not know the model on there, but im sure its the normal one) the guy who had the car before me switched the rear axle to the 9 bolt and thats about all i know on this engine.
A broken fuel pump forced my car to sit for a few days and taken off insurance and all that fun stuff making it from a daily driver to my project car. i replaced the fuel pump within a day and decided since its sitting, might as well replace my 4130 holley economy carb out for something a little more. i purchased a 625 street demon carb and decided to get to work on the car. i took the old carb off, saw the dirty intake manifold and the carbon filled interior of the manifold and decided to take it off completely and re do everything and clean everything up, both dirty and wire wise. I quickly checked the metal gasket that came with the SD to the holes to see if they lined up... the screws line up but the square shape does not line up at all with the holes in the manifold. the flaps on the bottom of the valves hit the metal of the manifold. my question is, should i replace the intake manifold? or return the street demon and get something to fit the manifold. if i put my finger inside the manifold where the carb was its like coarse sand paper. i was planning on cleaning all that out. also, the other question is, if i do change the manifold, does anyone know what would run good with the street demon? are there power differences in styles of manifolds? should i get the big open inlet, or the two holes? im a builder on a budget, so like 150-200 is my price range
Hey guys! i usually come here when i need some advise as most of us do, and today is no exception. I have an 85 Firebird with a 305 (from what i know is stock) with a manual 5 speed (sorry, i do not know the model on there, but im sure its the normal one) the guy who had the car before me switched the rear axle to the 9 bolt and thats about all i know on this engine.
A broken fuel pump forced my car to sit for a few days and taken off insurance and all that fun stuff making it from a daily driver to my project car. i replaced the fuel pump within a day and decided since its sitting, might as well replace my 4130 holley economy carb out for something a little more. i purchased a 625 street demon carb and decided to get to work on the car. i took the old carb off, saw the dirty intake manifold and the carbon filled interior of the manifold and decided to take it off completely and re do everything and clean everything up, both dirty and wire wise. I quickly checked the metal gasket that came with the SD to the holes to see if they lined up... the screws line up but the square shape does not line up at all with the holes in the manifold. the flaps on the bottom of the valves hit the metal of the manifold. my question is, should i replace the intake manifold? or return the street demon and get something to fit the manifold. if i put my finger inside the manifold where the carb was its like coarse sand paper. i was planning on cleaning all that out. also, the other question is, if i do change the manifold, does anyone know what would run good with the street demon? are there power differences in styles of manifolds? should i get the big open inlet, or the two holes? im a builder on a budget, so like 150-200 is my price range
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From: Bowdon, GA.
Car: 1988 Camaro
Engine: 355, 10.34:1, 249/252 @.050", IK200
Transmission: TH-400, 3500 stall 9.5" converter
Axle/Gears: Ford 9", detroit locker, 3.89 gears
Re: best intake manifold for 625 street demon?
Do not get the big open inlet type of intake. That is what's known as a Single plane intake.
They are made for high RPM power, and big cubic inch engines.
The two hole one is known as a dual plane intake and is best suited for I would guess 75% or better of the members on this site.
With each style there is many options and power gains and power bands.
Your factory intake and carb has a mount pattern known as a spread bore. Your speed demon is a square bore carb.
If you wanted to, you could buy a $25 spread bore to square bore adapter plate and make your new carb fit onto your stock intake.
Or if you want to buy a new one. Something like the edelbrock performer eps #2701 intake or Summit racing # 226012 intake would be a great match for your engine and new carb
They are made for high RPM power, and big cubic inch engines.
The two hole one is known as a dual plane intake and is best suited for I would guess 75% or better of the members on this site.
With each style there is many options and power gains and power bands.
Your factory intake and carb has a mount pattern known as a spread bore. Your speed demon is a square bore carb.
If you wanted to, you could buy a $25 spread bore to square bore adapter plate and make your new carb fit onto your stock intake.
Or if you want to buy a new one. Something like the edelbrock performer eps #2701 intake or Summit racing # 226012 intake would be a great match for your engine and new carb
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