Jump to content


Photo

Forced Induction Diesel Engine.


  • Please log in to reply
3 replies to this topic

#1 DeadSquare

DeadSquare

    Up Into Fourth

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 2,733 posts
  • Location: Herefordshire
  • Local Club: Unipower GT Owners Club

Posted 09 April 2019 - 09:15 AM

I am just pondering how high the compression ratio gets in a turbo-diesel ?

 

The only information that I have to hand is the BMC Mini Tractor workshop manual for the N/A 948cc engine, which has a compression ratio of 23.6 : 1.

 

 

 

 



#2 Steve220

Steve220

    Up Into Fourth

  • TMF+ Member
  • PipPipPipPipPipPipPipPipPip
  • 4,877 posts
  • Location: Shropshire
  • Local Club: RAF Mini Club

Posted 09 April 2019 - 12:57 PM

Severely dependent on the engine. My Audi 2.0tdi engine is 16.5:1


Edited by Steve220, 09 April 2019 - 06:06 PM.


#3 Ethel

Ethel

    ..is NOT a girl!

  • TMF Team
  • PipPipPipPipPipPipPipPipPipPipPip
  • 25,379 posts
  • Local Club: none

Posted 09 April 2019 - 02:44 PM

An old mechanical diesel has no way of adjusting timing for boost. The turbo will mostly counteract the reduced flow efficiency above peak torque if the engine was normally aspirated.

 

23:1 does sound high, but related to right sort of ignition pressure for a diesel that's running without starting aids like glow plugs.

 

Interesting engine I know nothing about, but always been a little curious.



#4 DeadSquare

DeadSquare

    Up Into Fourth

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 2,733 posts
  • Location: Herefordshire
  • Local Club: Unipower GT Owners Club

Posted 10 April 2019 - 08:44 AM

50 years ago, we had the use of the local agent's demonstrator for a month.  It was August, and I don't remember if it had glow plugs, but it didn't want to start in the morning.

 

Although I knew it didn't like starting, I perversely fancied putting one in a Mini.

 

Over the years I have acquired most of the bits for three engines, but there are problems.

 

1)   The crank needs a tail welded and machined for the flywheel, but I haven't found any one who wants to have a go at doing it.

 

2)   Alternatively, a 1300 crank fits with a bit of fettling, but it would require a spacer on the block because the stroke is point two inches longer, and the nose is too short and too small diameter for the timing gears, although this could be cut off and a left hand thread spigot screwed into the front main bearing and machined.

 

3)   When the crank is sorted, the injector pump is so long that there is no room for the starter.

 

4)   At my age, can I be trusted to cope with 15bhp, Lol.






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users