I have an Agency Power twin entry carbon airbox with no MAF and 2.75" pipes all the way to the turbos, we are trying to map the car and at 1.3 bar its showing approx 715hp using maths and figures from the log, when we turned up boost to 1.4 bar the mapper said it was making do diff and turbos need more air! Os is that about right 720hp limits of a stock based system?

 

stock intake on GT3582!Todd.K has nice fender well intake.

 

I was hoping to avoid a fenderwell intake at least until we put the forged motor in. I can make my own kit as all the fenderwell kits ive seen end up being beat to pieces to clear the inner tyre wall, my friends acr had some from an american tuner and when we made 3" pipework unhammered the mapper had to 20% more fuel in !!!

This is what I have, supported up to approx 720 so not bad for stock based.




These are the intakes from my friends car




We made these to replace them

 

Put a vac gauge on the intake side of the turbo to see how much pressure drop there is, this will give you an idea as to how much the turbo is having to struggle breathing through those pipes. You want as little vac as possible...

 

I think we pretty much know that the turbos are going to need more air.

 

those turbos need 3" from the top of the ICs... I have mine this way on 3582s since 2004 with various upgrades and options tried... forget that box... that simple... car made 980 whp at 1.7 bar on stock ecu...

 

Yeah thats the route im going, thanks Mark, still 720 aint too shabby on a stock based box.

 

Right. But do 3" you will be fine and make sure it clears the tires especially when it squats. Some put filters on the compressor but that's dangerous in my opinion. We tried these tricks back in 2004 - painful experience loosing a turbo.

 

Im going to do same as my above pics in 3", but have you seen this if you want to be really trick

http://www.burnsstainless.com/304ovalsstubing.aspx

 

I've experimented with oval stuff a few years back.

 

No good???
When will the Y pipe become a restriction?

 

You can't make turns with it and weld whereas with round you can.
Ur restrictions start with Intercoolers and more so the end tank connections on both top and bottom. Them the Yvpipe. You want to open it all up with 2.5" piping including the y pipe. In pics that's 2.5" intake but is good for 30rs.
U start with Ics and open it all up.

 

Im pretty sure this could be worked with

http://www.burnsstainless.com/90-350-s-304-oval.aspx
http://www.burnsstainless.com/rov-300-300-s.aspx

But I can squeeze 3" round in so its very much cheaper to do that.

 

Correct. It's just tight Don't be like the Middle East guys running with only filters on turbos. Lol. U will loose a turbo and possibly more.

 

Trust me Mark with the weather in the UK filters on the turbos is a no go from the start BUT whats the problem in a dry state/country, Ive always run filters direct on turbos in Mk4 supras no problem.