Sale ends todayGet 30% off any course (excluding packages)

Ends in --- --- ---

Throttle body 4 butterflys vs 1 larger

General Engine Building Discussion

Forum Posts



Tech Articles

Talk about engine building here. New products, tricky questions or showcase your work - If it's engine building related it's welcome here.

= Resolved threads


I am building a type 1 vw air cooled engine that will be turbo charged . it is 2498 cc the question I have is there a preference on using 4 40mm butterflys 4 inches from intake port, or use one larger one maybe 65mm butterfly that would be placed before a tee and about 15 inches from intake ports? the car will be a street driven /strip fiberglass buggy. any help is appreciated.

I'm guessing this engine will be fuel injected, so in order to use 4x ITB make sure the ECU you will be using can support Alpha-N (TPS as load) with MAP compensation.

I can't comment which one is better for those engine, I would probably ensure that packaging both options in the engine bay is not an issue.

For a street turbocharged engine, just go for a single throttle body. The added complexity of multi throttle bodies won't be worth the gain.

The main benefits of multi throttle bodies are throttle response and intake length optimisation. Stick on a turbo and those things become far less less critical than other factors (boost, intake charge cooling, compression etc).

We usually reply within 12hrs (often sooner)

Need Help?

Need help choosing a course?

Experiencing website difficulties?

Or need to contact us for any other reason?