Twincharging - can the supercharger be too small? 1

[junglerc]

Hello,

I have searched and read the previous threads on twingcharging. I understand the recommendation is to go huge on the turbos and small on the supercharger. Sounds good and fits well with what I'm planning.

Question is: Can the supercharger be made too small?

 

[patprimmer]

Yes


Regards
Pat
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[junglerc]

I mean, besides the obvious.

Say a very small overdriven supercharger, with a decreasing boost curve when operated by itself compared to a larger supercharger driven slower with stable boost curve.

Which would provide less parasitic losses when compounded with the turbos?

Would the larger supercharger still be the more efficient setup if cam timing is optimized for exhaust scavenging?

Total pressure ratio expected at intake manifold is 3.5 - 4:1. The turbos in mind are more than capable of providing the power and pressure ratio, but surge line comes in pretty high. Looking at the super/turbo combination to improve spool/surge line.

 

[Lou Scannon]

As you design your application, you have to determine the operating range that you're expecting from the supercharger. Then you select a supercharger that best suits this range and your performance goals. If your desired range exceeds what's available on the market, then you have to compromise (overspeed the supercharger, with associated loss of efficiency & risk of failure; or pull back your performance goals).

 

[patprimmer]

If you state precisely and concisely what you actually mean, you will greatly increase your chances of an accurate answer.

Most here can't be bothered drawing a question our of you or trying to second guess what your actual meaning is if you can't be bothered drafting a decent question.

You should use within reason, the smallest supercharge and drive ratio combination that will stay within it's efficient speed range over the operating range of the engine.

You may also be advised to consider weight and packaging issues when deciding between several that are of reasonably suitable airflow.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

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for site rules

 

[junglerc]

Thanks