Noob Question

[Flip1977]

Hi Guys,

I've been looking through the website for a thread that gives a walkthrough for how to get to certain power levels to no avail. I am thinking of buying a Legnum (how DO you pronounce it??) VR4 but I want to know how to get that bit extra (spend far too much time on the bike, nicking my mate's 350z or playing in caterhams for ONLY 280bhp in a big estate!!)

I'm not looking to go insane, probably around the 350bhp mark or so, so what is the most cost effective way of getting to that point?

May the lessons begin....

Flip

[Flip1977]

I would consider the Unichip, I had one of these in my 406 turbo, got it to 238bhp with that and a few other bits and bobs... Quite a good "bang for buck" I found - and I see they are mentioned on here, but not with many figures attached!

[conaboy]

There's a lot of info on the site about the sort of mods your talking about.

You would need to look at exhaust/decat and downpipes, boost controller and fuelling (either dastek as you've mentioned or e-manage/SAFC etc and probably an uprated fuel pump to be safe) to get close to 350 bhp. Probably better intercooler and cold air intake aswell. It all adds up!

Think the best bang for buck mod is a boost controller and turn it up to 0.9 bar. Should see a good increase with that.

[Flip1977]

By the sounds of it the stock airbox is better than the cone pod affairs I normally favour, so is the best bet to stick with the stock air box, and get a boost controller in there? What should I knock it up to and how much bhp should I see from that?

[conaboy]

By all accounts, the stock airbox is very good. I still have mine with a K&N panel filter. Some people have an enclosed cold air setup like the ARC box but yet to be proven on the dyno.

Not too sure about the figures and I may be corrected but with boost controller set to 0.9 bar, filter and exhaust you should be close to 300 bhp. The VR4 also runs very rich, best to get the fuelling sorted. I'm still waiting to get my Apexi SAFC fitted myself but believe this is the next good 'bang for buck' mod.

[Axeboy]

Boost controller set at 0.9bar transforms the car.

I could never go back after that.

[Kieran]

Yeah, 0.9 bar is a safe limit if you've not got anything in place to monitor and alter the fueling. And yes - 0.55/0.7 bar to 0.9 doesn't sound that much, but in terms of grunt.... It's a lot!!

And then you've got loonies like Nick man who run 1.1 bar (with fuelling and mapping mods to suit).... They're almost intergalactic!!:dizzy2:

[Funkstar]

Here's one of my favourite threads on the site. The posts from Valmes are a great beginners guide for modding the VR4 (IMHO).

http://www.clubvr4.com/forum/showthread.php?t=16029&highlight=favourites

[conaboy]

Good info, couldn't find that post earlier.

Couple of things I noticed when reading it again, can someone explain the difference between MBC and EBC and how they control boost differently?

Valmes lists

'MBC+Boost gauge (not bleeder type, but ball and spring type)'

then says

'Right now you should FEEL improvement even at stock boost, but go ahead and install your ball and spring MBC set at 0,6 bar. Better disconnect your stock boost solenoid at this time. This MBC type will give you instant turbo pick up (since it doesn’t let pressure to reach actuators until you already have 0,6 bar!!!'

Is there a benefit in having the MBC over an EBC??

One other question, if a boost controller gives you control over what boost the actuator sees and therefore when it opens the wastegate, what is the benefit in fitting stronger actuator springs, also listed in Valmes post??