stockcar

what you're describing is quite normal...........you will always get more boost in 5th gear because of the simple fact that the more work you give the turbo to do the harder it works.........this is why when you see people doing top speed runs the quickest way is to "short shift" into 5th asap to achieve maximum boost
alyn - as performance

dominicm

I have owned 2 x EVO's, a RX7 and a Supra all of these had uprated ECU's etc and boost gauges and none of these used to fluctuate like my scooby does....any reason for this?

Dom.

john banks

You do describe rather a large difference though. Perhaps your Link boost control variables need adjusting or the wastegate/hoses/solenoid need checking.

bwhinnen

I'm not an expert on the Link, far from it, but I've just started working with one in my car so here goes nothing (Note: take everything you read here with a small grain of salt as I could be wrong

Firstly what model is it? What boost solenoid are you running? The two port or three port model?

I've found the 2 port model needs a lot of tweaking to achieve boost consistanlty, and it generally won't hold it in the higher rpm ranges due to it not being able to vent enough air off.

If all of your pipe work from the turbo to actuator to solenoid is in place and you have the correct restrictor, start looking at the WGBASE and SENS settings, the higher the WGBASE the quicker boost will rise, and overshoot before settling, the lower, the slower it will rise, you need to find a happy medium. SENS will determine how well it holds boost once you are there, too high and it oscillates, too low and well honestly I don't know , also there is the WGRPM value that determines when the Link will start 'actively' trying to control the boost, depending on when your turbo can reach high enough boost is when you should set this, ie when you have enough exhaust gas flow to start creating an over boost situation.

Ideally if you don't feel (or can't) make these adjustments find someone who know's Links and tuning, they'll be able to help.

Cheers
Brett
MY00

(A link novice <- in all honesty)

dominicm

What could be the reason for my boost always being different? Recently I have had 550cc injectors, uprated pump and reg. and a Link ECU fitted.

Some times my boost gauge shoots round to 24psi and drops off slightly to about 19psi, sometimes it only reach's 17psi and then drops off to about 15psi etc etc etc!

It also tends to reach higher boost in higher gears, as a rule if I boot it in 5th it normally peaks in the 20's and in 1st or 2nd it normally peaks at about 17psi!

I realise that cold weather etc can effect the boost but I dont think it effects it as much as mine...also I thought that the car should reach slightly higher boost in the lower gears!

Cheers
Dom.


[Edited by dominicm - 4/10/2003 7:54:53 AM]