2bbl to 4bbl pictorial

Triple Pickle

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As someone once said, “ Some people have a way with words. Other people,,not, have way, I guess.”
Here’s what I hope is a self explanatory pictorial of how I deal with throttle/kickdown issues by modifying the factory bracket when replacing a 2bbl with an aftermarket intake and 4bbl.
As we see, the height difference is where the heartache begins....also note how much higher the thermostat is on the aftermarket intake.
This is a 360 2bbl intake and a aluminum Wieand 2p 180 intake side by side comparison. Accessories such as AC compressors may be affected by such modifications as well.

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This mess will not work. This is a Carter AFB. Different carbs, different issues. Check the carb you’ll be using for different measurements.

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Cut the part of the bracket where in bends. Use flat bar of similar dimensions to add the heights you need. In this case it was 1.25”

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Using the old intake for a fixture, bolt your new tabs down through the holes where the original bracket bolted. Then clamp the bracket to them and tack weld. Check to see if it lines up with the carb before final welding.

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Also, you’ll have to extend your kickdown rod that goes under the car to the transmission. This is important if you want your transmission to last.
IMPORTANT: ALWAYS MAKE SURE YOUR THROTTLE LINKAGE WORKS FREE AND RETURNS TO IDLE POSITION. Spend more time checking that than anything else in this pictorial!!!
 
Thanks for the pictures and graphic instructions. Any particular reason you selected the manifold you did? Just curious. It appears to be a "high rise" rather than OEM replacement. The manifolds which have the thermostat housing as the one you have is for the RV-2 OEM compressor as the later Denso compressors have the mounting flange rotated a bit for compressor mount clearance. Or have the dual locations as the Edelbrock Performer LA intakes do.

Thanks,
CBODY67
 
Similar situation regarding my Performer 440 intake. The carb flange height is about 1 3/4 inch higher than OEM, which necessitated raising the throttle cable mount the same distance. Otherwise, the cable and carb linkage clashed and didn't operate in "harmony".

Kickdown actuation was generally unaffected, but must be carefully studied for correct movement and adjusted accordingly.

OEM bracket height:
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Raised, welded bracket height for Eddy 440 Performer intake:
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Thanks for the pictures and graphic instructions. Any particular reason you selected the manifold you did? Just curious. It appears to be a "high rise" rather than OEM replacement. The manifolds which have the thermostat housing as the one you have is for the RV-2 OEM compressor as the later Denso compressors have the mounting flange rotated a bit for compressor mount clearance. Or have the dual locations as the Edelbrock Performer LA intakes do.

Thanks,
CBODY67
I already had this intake on a parts vehicle. I wouldn’t call it “high rise” at only 1.25” over a stock 2bbl. I consider a high rise to be a single plane that is 3 or more inches over stock.
I reckon an OEM replacement wouldn’t require the butchery shown here.
 
Thanks for the information. To me, a "high rise" is like the old OEM Camaro Z/28 4bbl factory manifold, which was higher than the normal 4bbl intake. Enough higher that the factory air cleaner base pretty much engulfs the 3310 Holley that came on those engines. A fill 1 inch lower than the more common aftermarket knock-offs.
 
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