Screw Mod

Yes, upping the boost pressure on a non existent turbo is going to be a challenge.....

I think some have missed the whole, whats the screw mod idea.
 
On a non-turbo diesel all you will get it lots of black smoke and crappy MPG. You need to put more air into the engine to burn the extra fuel, and without a turbo that's going to be difficult.

I've read posts from people asking about making the 1.9 N/A Diesel engine a little bit better, J.A.C who tunes a lot of these engines said that you can get some gains from the N/A's :)

You are quite right though, you will get lots of black smoke if you go too mad :p
 
Its upping the fuel and boost pressure or how the actuator arm opens to produce more power, no point in adding more fuel without sucking in more air, its going to give you nothing except bigger fuel bills.
 
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Its upping the fuel and boost pressure to produce more power, no point in adding more fuel without sucking in more air, its going to give you nothing except bigger fuel bills.

You don't actually have to up the boost when increasing fuelling as TD's are deliberately run with an excess of air to reduce emissions. Above a certain point you will need more air though.
 
Its upping the fuel and boost pressure or how the actuator arm opens to produce more power, no point in adding more fuel without sucking in more air, its going to give you nothing except bigger fuel bills.

Not true, on the 1.9D you CAN get gains from adding more fuel because they are set to run lean.
 
Its got to be very minimal power increase, as stock it puts out 60bhp and seeing as upping the fuel and boost on yours only gives and extra what 18bhp? i can't see a smaller non turbo lump gaining anything worth the while, i can't see it underfueling that much?

Whenever anyone has ever talked about the 'screw mod' before it has always been about the turbo variant of the 306D engine, never about the N/A verison.
 
It's probably no more than 10bhp in return for some smoke.

Mine is purely a guestimate at 110bhp. Most decent 'Stage 1' (screw mod) tunes return about 115bhp or 120bhp depending if you want to put up with smoke. Mines just a mild tune, but a very noticable one. It makes the car feel faster than it is because the power comes in such a big surge :)
 
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