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Troubble tuning turbo engine.

1623 Views 3 Replies 2 Participants Last post by  Nova67ss
Hi there expert panel

We have a problem with the syclone my friend build....V6 Turbo engine aiming for 1100 Hp ( )
Komponet failur or tuning?? we dont know and starts to run out of ideas..

Problem.. runs fat on idle when tipping the trottle it backfires from 1800 to around 2800 BUT the FAST loggs it like real FAT mixture?? runs fair from 3K and up..

When checking ignition we read a steady 0 without the FAST box but with the box in circut and 30`ignition (steady value in computer) its hoovers around 27´to 36´so fast you cant see it on the damper just what the computer loggs???? we´ve changed the FAST box with 2 other unit and the same problem occurs..

The idle and litle of the stumbles around this was a LITHLE better when changing pluggs from non projected to projected pluggs but not much

Even the injektors been checked, al wiringharnes. the crane box bypased and a regular ignition put in.. same problem..

Fuelpump is a weldon unit with a voltidge regulator unit to ceep pump rpm down when crusing and idle goes full acction went pressure or/and RPM demands it.

We´ve changed everything exept the distributor itself, but we´ve changed the parts inside it several times..

The FAST system is a self adjusting system with a lamda sond. but it goes from 12,5 to 15.1 in almost av vave form and its impossible to ceep it steady to target 13,3 just loops around

All this occurs benith 3K rpm and makes it dificult to make a good tune on the car..

anya ideas??

All help/ideas is valuble to us now..

Best regards Anders
Gotenburg Sweden
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Anders, why don't you ask a hard question!!:eek: :eek:

I don't have an answer to offer, but I can give your question a bump up to the top of the list!!

Randy (still has trouble with carbs!!):rolleyes:
Randy :D I wish to give and Q that was a "Hard" q this all sensors,triggers and computer stuff makes me go nutts.

And Robbert is a good and neet mecanic, not an electritian though so I help him sort out som minor problems with the virings and relays. fun to help in a nice car and not a pice of junk.
This evening we will try again. we´ve probably pinned down the problem itself..

And when this is done and the car runs fine, we will all take a cup of swedish stroong coffe and laf our jaw´s off..
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