make r33 run leaner???

[twoquik]

Is there any way of making my r33 run leaner without getting a safc but still running higher than stock boost?

because at the moment it has a flat spot after it hits full boost.

Ben

[BMCGTR]

Have read de-screening air flow meter will, if someone can back this up.

[BBQ]

Is there any way of making my r33 run leaner without getting a safc but still running higher than stock boost?

because at the moment it has a flat spot after it hits full boost.

Ben

If anything you would want it to run richer then leaner. As running an RB25det lean will cause your stock pistons to melt.

If you are really that desperate to make it run lean, Buy a power fc, so you know exactlly how lean its running.

[Sydneykid]

I have yet to see a single RB25DET with standard ECU that goes lean when you turn the boost up. They start off rich when standard and just get richer the more boost you add.

PS; the cheapest way I know to lean them out is with a Jaycar Digital Fuel Adjuster, take a look at the Stagea thread for details.

[mabru]

I actually lean mine out a little bit across the board using the SAFC, they do run a bit rich stock. I only drop like 2% or so and it still sits a little rich on the AFR gauge. My old RB20 had the same issue only worse, smelled like a gas station behind it.

[KamikazeR33]

the cheapest way would have 2 b a hose clamp on the fuel line seen this done b4 so dodgy but works but a a/f guage would help in this case also

[ylwgtr2]

flat spot generally means lean

[BBQ]

I have yet to see a single RB25DET with standard ECU that goes lean when you turn the boost up.  They start off rich when standard and just get richer the more boost you add.  

Have had experience with 2 Rb25det running lean with stock computers, Once more boost has been added. Melting stock internals.

We had one dynoed at 14psi. With stock turbo, Stock inj, Front Mount, and Stock pump, And afr was 30:1.

It only lasted a month or 2 after the dyno. Now re-buit with Forgies :flamed:

This is what happens if you run it too lean:

http://www.skylinesaustralia.com/photopost...lt_number_6.JPG

[cameron]

Their is a way to make the fuel mixtures more leaner.

The vacume hose going from the manifold to the fuel pressure regulator on the fuel rail, add negative pressure on it. eg: put a brass restricter inside it like one thats in the stock boost hose, To make it richer take the hose off & bloke manifold side up.

This should only be done with a stock ecu not aftermarket - PFC etc.

Jun

[Sydneykid]

Their is a way to make the fuel mixtures more leaner.

 

The vacume hose going from the manifold to the fuel pressure regulator on the fuel rail, add negative pressure on it. eg: put a brass restricter inside it like one thats in the stock boost hose, To make it richer take the hose off & bloke manifold side up.

 

This should only be done with a stock ecu not aftermarket - PFC etc.

 

Jun

Yep, you can do that, or fit an adjustable fuel pressure regulator and turn it down (instead of up, as is normal to increase the fuel flow). But that changes the whole fuel map, and I have yet to see a standard ECU Skyline that needs to run leaner everywhere, they always need either to be little richer or stay the same at many load points.