Evo 8 vac removal

[chris10]

Hi lads I'm new to this site. I've owned my evo8 fq300 for few months now and the time has come to modify for more power. I have got a lad sorting my inlet manifold out he's chopping up my old one and putting a bigger chamber on etc.. I am thinking of getting rid of all the vac system. I have already removed the EGR system and put a header exhaust manifold so I was just wondering if anyone has done this and which ones will I be able to rip out and which need to stay??

 

[RsvRob]

Most of them do something so they need to stay. You won't get power by removing them. If you intend to upgrade the plenum chamber you'll need to upgrade the throttle body and complete pipework from turbo to inlet or you'll just be dropping pressure. The magnus inlet chamber is the only improvement on std that I know of. Std is good for 500bhp cars. Unless your looking for that extra minimal bhp at a large cost.
The EGR is actually the SAS system that you have removed. This aids in turbo cooling and pops/bangs.
I hope you've fitted a quality make of exhaust header aswell. As most seem to be to thin and cracked at the weld points.
You would benefit from a stainless 3" turbo elbow more. To give better throttle response.

 

[chris10]

Right so you would advise not going for the inlet?? What about ported and polished or would that have the same effect and would also need the head done to match?? Also do the fq400 use larger injectors as I was thinking of going down that route and then get it mapped in. Cheers for the help

 

[RsvRob]

Ported and polished is fine. As all tour doing there is smoothing the transition of air.
Your std injectors are ok at the minute but will be maxing out at 400bhp.
Read the sticky on stage 1 mods in tech section. Will give you a better understanding and explanation

 

[chris10]

Thanks for the info mate I took your advise and put the inlet back on. The injector seals are now leaking unfortunately. I did expect this to be fair as I'd taken them out and they did look a bit cracked. Would you say bigger injectors will give me increased BHP with a map to go with it and would I need to map it straight away after fitting the injectors ?? Cheers for the help dude nice to talk to someone who actually knows what they are talking abot