×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Supercharger boost control

Supercharger boost control

Supercharger boost control

(OP)
I'm supercharging an Alfa 145 ts. It's a 2.0l engine that makes 155bhp as standard, i'm only looking for 200bhp, at the moment. I'll be using a Rotrex centrifugal compressor at about 4-5 psi. The unit I currently have is good for about 300-350bhp. A specialist says I should use a restrictor on the inlet to the compressor so that I can still spin it at it's most efficient rpm. I'm thinking I could take advantage of bringing boost on a little earlier in the rev range and then dump excess boost as revs climb.
 I know this isn't ideal but i'd welcome any thoughts on whether I should do this and if so, what's the best method of bleeding off the excess boost, bearing in mind it has to go back in to the induction loop after the MAF.

Many thanks.

RE: Supercharger boost control

Move the MAF post compressor?

RE: Supercharger boost control

The restrictor is also an effective method of boost control, allowing you to spin the supercharger harder to make more boost at lower rpm while controlling boost at higher rpm. "Spinning at its most efficient rpm" is not really the issue because the speed lines are close to horizontal near the suge line, which is the part of the map you will be using with an oversize supercharger. (I assume it's oversize although you don't say at what P.R. the compressor flows 350 hp). Anyway, if it is oversize, the restrictor will help keep your operating point away from the surge line.

Engineering is the art of creating things you need, from things you can get.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources