- NEED EXTRA VACUUM ON BIG CAM 350 HOW TO
- NEED EXTRA VACUUM ON BIG CAM 350 MANUAL
- NEED EXTRA VACUUM ON BIG CAM 350 SERIES
So, will a bigger carb make more power? Looks like bigger is not always better. Remember these numbers were from wide open throttle. Probably one of the best facilities around.
NEED EXTRA VACUUM ON BIG CAM 350 SERIES
Now this series of dyno pulls was on the Westech Performance dyno. The test was four Holley XP series carbs, 650, 750, 850 and 950 CFM. Here is what they learned.īase Engine 383 stroker Chevy Small Block:Ĭomp Cam hydraulic roller cam 230/236 50Ī better than average 400 HP street performance engine. Will a bigger carb make more power? Recently the Engine Masters show on the Motor Trend On Demand site did a comprehensive test to see just what differing sized carbs would produce.
NEED EXTRA VACUUM ON BIG CAM 350 MANUAL
Mechanical secondary carbs are best used on applications with more radical camshafts, high rpm racing situations, and manual transmissions. Vacuum secondary carburetors have one accelerator pump and work off sensing the engine load, which progressively open the secondary butterflies as rpm increases.Ī mechanical secondary carburetor uses mechanical linkage to open the secondary butterflies and most also have dual accelerator pumps (a.k.a. You’d be better off with a carb smaller than needed rather than something oversized that can lead to poor drivability and performance.Ī vacuum secondary carburetor is usually most fuel efficient when it's used on street driven cars that have automatic transmissions. If you try this formula yourself, be honest with how much rpm the engine will see. Most rebuilt street engines with average bolt-ons have a volumetric efficiency of about 85%, while race engines can range from 95% up to 110%.Įven with about a 10% cushion, a 500 CFM carburetor will handle this engine great.
NEED EXTRA VACUUM ON BIG CAM 350 HOW TO
How to calculate Carburetor CFM The formula for calculating how much CFM (cubic feet per minute) your engine requires is: CFM = Cubic Inches x RPM x Volumetric Efficiency ÷ 3456.Īny ordinary stock engine will have a volumetric efficiency of about 80%. The engine's volumetric efficiency is a measurable value and with a correctly matched carburetor, you will improve the performance of your engine.
The right idea would be to match the carburetor to the engine's breathing ability or volumetric potential. While we’ve all heard people say - “Bigger is Better” - is that always true? We know that more air and fuel equals more power, does that mean the biggest carburetor always makes more power? Unfortunately, too much carb is a common mistake that can actually hurt the overall performance of your engine. You can always contact us for answers to specific carb questions but read on to answer some of the most frequently asked questions about carburetors. We can help you choose the best carb that will work for your vehicle and how you plan on driving it.
Performance Improvements stocks carbs from Holley Performance, Edelbrock and Proform Parts. Sometimes people either have a preconceived notion of what size carb they want or they need some direction about what to choose. Will a bigger carb make more power? What size carburetor is correct for my engine?
0 kommentar(er)
