S40: TPS - readings

[mitchyboy01]

Originally Posted by 960kg

Mitch ,just a question as things don`t seem to match up!

On another site you say that you believe your MAF is maxing out at 195g/s
about 250bhp

So why did your Dyno run say 285bhp??

What has happened since?......although on here we never see eye to eye as we come from different angles of thought.

I am on the track of your fuel return system as the reason a T4 doesn`t have one is because the fuel has to be kept at 50 degrees for optimum performance.

If you read your own link to vadis it is to keep fuel LOWER than 50 degrees not AT 50degrees. The lack of return line is for emissions reasons only, not engine performance.

[mitchyboy01]

Originally Posted by 960kg

Still a bit off!

I don`t know what model you refer to and the year but i cannot find that part number at all!
That hose is probably from the FPR right near the tank as in the pic.

This is the Correct Volvo reason no return is fitted to early T4`s

As said in the link constructing your own return is not necessary until 350bhp approx is reached as it just copes.

Fitting a return line is necessary to run an adjustable fpr. When tuning it is often that some fuel pressure adjustment may be needed to get the fuelling spot on. Especially with a generic map. Custom maps are impossible to come by on the T4 these days so you often need to play with fuel pressure as a compromise. Obviously dyno runs or an afr gauge are the only way make sure the adjustments are working. When upping the boost on my car I found the stock injectors struggling. Answer, turn up fuel pressure a notch. Afrs now ok. When going silly with boost even with fuel pressure at max the stock injectors struggle. Answer fit VXRs. Now too rich. Turn fuel pressure down to minimum. AFRs now ok again. Without adjustable reg you cant do this.

[960kg]

Originally Posted by mitchyboy01

Fitting a return line is necessary to run an adjustable fpr. When tuning it is often that some fuel pressure adjustment may be needed to get the fuelling spot on. Especially with a generic map. Custom maps are impossible to come by on the T4 these days so you often need to play with fuel pressure as a compromise. Obviously dyno runs or an afr gauge are the only way make sure the adjustments are working. When upping the boost on my car I found the stock injectors struggling. Answer, turn up fuel pressure a notch. Afrs now ok. When going silly with boost even with fuel pressure at max the stock injectors struggle. Answer fit VXRs. Now too rich. Turn fuel pressure down to minimum. AFRs now ok again. Without adjustable reg you cant do this.

I did have a similar adjustable FPR on my 2 litre 940 redblock turbo so your words are not wasted i do understand.

[Slevin]

Originally Posted by 960kg

Still a bit off!

I don`t know what model you refer to and the year but i cannot find that part number at all!
That hose is probably from the FPR right near the tank as in the pic.

This is the Correct Volvo reason no return is fitted to early T4`s

As said in the link constructing your own return is not necessary until 350bhp approx is reached as it just copes.

Where can i find this "topic" in Vadis Keith?

And Mitch, i will fit the return line,as i definitely need it(you know what ECU i will use)but i did not understand how this thing works,cuz i saw the outlet and inlet mark on the AC.

[960kg]

Originally Posted by Slevin

Where can i find this "topic" in Vadis Keith?

And Mitch, i will fit the return line,as i definitely need it(you know what ECU i will use)but i did not understand how this thing works,cuz i saw the outlet and inlet mark on the AC.

I have looked, looked, looked, looked, and that part number is not anywhere or any year or any model!

[Slevin]

Here is that part number.

But i meant where can i find that description you attached?

[Slevin]

I have checked my TPS and MAF as well and i got only 78.4% at WOT and 3.0-3.2g/s air mass at idling.Why is not 100% or close to 100%?

[malteser]

By the way Slevin Tim is selling the fuel system that was on Mo's car

[Slevin]

I got a standalone ECU by now so doing my own way (i mean dont have to copy Mo's car as i wont use his ecu).

[malteser]

okay thought you was using that ecu