[Guest]

Finally bought a HKS Hiper Muffler Ti and a scorpion de-cat for my TME, the look, fitment and sound are great.

I feel as if I have lost the 'urgency' or sharpness of the acceleration. It still pulls well, probably more power up top, but midrange seems to have suffered. There also seems to be more lag !!!!!!!!!

Would this be the loss in back pressure from removing the cat ? Would I be better of in sticking with the cat and using the cat-back HKS exhaust ?

The only other engine mods I plan are a Ralliart ecu and a boost tweak.

I did prefer the way the car felt as standard - it did feel quicker, or is this just me ?

Comments / thoughts would be very welcome.

Daz

p.s I have the Ralliart panel filter and HKS blow valve (Which will be removed soon as I'm getting ####ed off with the noise).

 

[Guest]

i feel the first mod you should do is an ecu with datalogging capability. you can then log the boost and rpm every 1/4 second flooring it at 2000 in 4th with the car otherwise standard. then do any mods such as this exhaust change

log again after mod (try and use same stretch of road and similar atmospheric conditions) and compare the logs

any change in spool can easily by comparing MAP reading at each log point and as can the rpm which will show where you have lost or gained torque

i didn't follow this but with hindsight will do next time, so the gains and losses of any mod can be scientifically measured and sleepless nights avoided

andrew

 

[Guest]

Sorry to hear the mods haven't done what you hoped for Daz, no good asking me though I haven't got a clue really, sorry.

However, if you're going to be parting with the panel filter and HKS valve I may be interested in taking them off your hands Lemme know if you decide to ditch 'em

Good luck with the hunt for more power from your mods

Dave

 

[Guest]

Dave,

I am happy... sort of !

Might get the bolts done, then praps a boost upgrade.

I'm boosting at about 1.1 peak / 1.0 sustained.

 

[Guest]

Daz, get the downpipe, it improves the mid range. And up the boost!

Maybe get a cheap ECU that has knock control etc. Do you know of any, evotrak? I heard in Australia they make some good ones cheap. Ideally, if you do not know how to map it, if you could get a map off the net or something, that would be really great, dont you think Daz?

 

[Guest]

Claudius,

Sound Ok to me.

When they up the boost with a standard ecu do they just change the size of the restrictor ?

When you took me in your car (September last year) what set up was you running then ?

What boost did you have ?

Thanks Claudius.

See you soon.

Daz

 

[Guest]

Daz,
U shud have gone 4 the Blitz

 

[Guest]

daz

i know what u mean fells a bit flat, and needs more revs to get moving.....up the boost a bit
if you only really want the noise and are not to bothered about the top end, put the cat back.

lee

 

[Guest]

claudius

lol, 1.7 in the midrange, not complaining about lost torque thats for sure ,don't even need the first two gears
now just to find some decent fuel to stop it blowing up...

andrew

 

[Guest]

Daz,
I know it doesn't help but with my blitz, decat and down pipe there wasn't any noticable reduction in my lower end or increase in lag, just a bit better mid range and much better top range, maybe the downpipe would be a good idea.

R

 

[Guest]

Hi.
Over the space of a few weeks I modded my 6 in stages, the mods went: Magnex cat back exhaust, HKS RSK, then a Magnex de-cat pipe. I gained power with each modification and lost no performance what so ever. It was interesting to see the boost rise after each stage of modification. After the de-cat my boost went from 1 bar held to 1.1 bar held and now it feels bloody quick. I know the scorpion is narrower than the Magnex but I cannot see that would make any difference. Maybe the HKS RSK is your answer?

BTW. If anybody is using a Magnex de-cat and wants the correctly sized gaskets then call ABP and ask for the Blitz ones

Regards.
D

 

[Guest]

ABP??

Rich.

 

[Guest]

Original Post:
Claudius,

Sound Ok to me.

When they up the boost with a standard ecu do they just change the size of the restrictor ?

When you took me in your car (September last year) what set up was you running then ?

What boost did you have ?

Thanks Claudius.

See you soon.

Daz

Daz,

when you were here, my car was standard. Or maybe I had the exhaust already. That's a HKS Hyper Muffler with GT extension kit (tubo elbow and downpipe). Boost was standard, less than 0.9 bars.

 

[Guest]

Original Post:
claudius

lol, 1.7 in the midrange, not complaining about lost torque thats for sure ,don't even need the first two gears
now just to find some decent fuel to stop it blowing up...

andrew

Hehe, good to see you got me the right way I'm sure you have the best ECU set up here...

 

[Guest]

Daz - Would be very interested in the BOV ...

[email protected]

 

[Guest]

claudius

dunno about best - but probably cheapest! - can autotune your ignition map as well as your fuel
actually i am going to ditch it and get a plus, much better imho, plug and play job is easier to fit but lags behind feature wise

not that i follow my own advice...but making random changes without having any way of accurately measuring things is not such a good idea

turbo needs a high initial exhaust velocity to get it spinning quick so bigger pipe |EQU| slower velocity |EQU| slower spool
problem is that high initial velocity means even higher velocity later which means more back pressure which means less flow higher up which means less power

poor boost control circut coupled with soft wastegate means premature opening which means slower spool so can recover most of what you have lost and possibly even gain by fixing this, and still retain the advantage of bigger bore exhaust further up the rev range

not going to get far on the standard ecu due to the infamous fuel cut problem, sports seems like a bad idea cos if it does flatten the timing at high rpm then your egts are going to rocket and even if the lambdas look ok (lambda probe doesn't know where the fuel is burning) you may end up poping a turbo or something

andrew