H2o-uk

iTrader: (1)

Hi all,

As I've stated in the thread title, I'm a little concerned regarding the mods I have installed on my car. Its an 03 WRX with 35k on the clock, and Ive only had it a couple of months, but I've slowly modified it with the following :

Prodrive Backbox
Prodrive Intercooler Y-Pipe
Prodrive Centre Decat pipe
De Resonated rear pipe
Green Cotton Panel Filter

Now I've asked this question a couple of times previously and had various responses and of course the thread always ends up off topic. But after reading some other threads recently regarding decats etc, its got me a little concerned. Some people have stated that all this on my car will be fine, and should be okay without a remap, however other opinions suggest that by removing any of the cat pipes a remap is definately required. Obviously I dont want my engine to go bang, and this is my daily driver, and I usually do 15k miles a year. I'm not planning on having a remap until later in 2010. So is it safe ? should I remove the decat and refit the original pipe.

All help and advice greatfully received, thanks.

johngoulding

iTrader: (7)

the main problem with the decat mate is spiking at the top end . if u have the fuel cut on ur model then a spike now and then wont harm it too much but isnt advisable , if you have a boost gauge then keep a serious eye on it at wide open throttle and if it doesnt spike EVER i would say as long as you treat your car well then a decat wont do to much damage BUT EVEN A SLIGHT NOTICE OF THE BOOST RISING HIGHER THAN IT SHOULD THEN I WOULD SUGGEST A REMAP also check that the boost holds steady on the needle or gauge if it does when at full boost i would save the remap just now and just make regular checks especially in regards to spikes as sometimes they can be that quick that u wont notice or you wont be looking at the gauge ull be looking at the litle sh*t next to u in the civic givin him the finger as ur passin him and his bird wishin she was sittin on ur lap and not ur passenger seat lol

johngoulding

iTrader: (7)

if ur also going to keep the decat and u r thinking off mapping in future then i at least recomend an uprated pump as theyre cheap and help things out a lot

H2o-uk

iTrader: (1)

Thanks for the response, I dont know whether or not I have Fuel Cut on my car, and I dont have a boost guage. What are the symptoms of boost spike and I'll try and keep an ear out for them.

johngoulding

iTrader: (7)

also in my opinion i wouldnt say prodrive packages offer much performance increase in regards to whats on the market right now price wise anyway ? imo prodrive is the uk's version of sti as not much people with decent hp use prodrives stuff , i could be wrong here but its only my opinion , in relation to older cars sti's were jap imports only not sure about the newer models and prodrive did the uk cars like the p1 which didnt vary much performance wise for the extra god knows how many thousands more expensive it was for the sake of buyin an import sti and adding parts for it to basically be the same in relation to performance but i do say they made it look really good , sorry for goin off topic a wee bit a was getting excited

johngoulding

iTrader: (7)

without a boost gauge mate there is no way to tell , i have a boost gauge that im selling that no one seems to want as i didnt post pics of it lol , its basically brand new will post it to you and you can have it its a white one that measures vacumm on idle which if u learn to read the gauge it can tell u if u have vacum leaks , bent valves cylinder leakage etc there is a big guide on the net on how to read a vacum gauge also when u floor it it reads the boost level instead of vacumm ,.

in regards to WHAT IS A BOOST SPIKE , just say ur running 1.1 bar of boost , u floor it and it goes to 1.1 easy then suddenly it goes higher than that , say 1.2 or even 1.3 this causes the engine to run lean ( not enough fuel to air that is passing through ) and can cause meltdown , basically a hole in the top of the piston or the sides of it also known as detonation when ur running lean hence why i sugested the fuel pump , think theyre about 50 to 70 quid , easy to install as the panel opens in the bootfloor area and these can sometimes help as the fuel gets to the engine better in laymans terms and stops light cases of a lean condition , none the less a spike can be a deadly thing for an engine .

pm me ur adress mate and i will send u the boost gauge for free , rather that than ur car go boom due to u not knowing when its spiking or overboosting also it would be handy to find out what the standard boost limit is for ur car for this u would need to check the number on the ecu underneath the passenger side carpet in the footwell area , just take up the carpet unbolt the footrest plate and voila read the number and ask on a thread what the standard boost limit for the ..ecu is (.. relates to ecu number could be 3c, 4c, z4 etc ) if u ever find out what the standard boost limit is which should be relatively easy , just say its 1.0bar and ur running at 1.1bar that should be ok as long as it holds 1.1bar at max boost or wide open throtle ( foot to the floor ) if it holds 1.1 then jumps to 1.2 etc thats a spike , a small one at that but still a spike as some can overshoot by nearly 0.5 a bar ( 1.1 to 1.6 )

long story short mate lol pm me ur address and i will post u a boost gauge for free , all u will need is a pod , holder or whatever u r going to use to hold the gauge on the dash and some piping to plum it in to the vacuum lines ( diagram also available for plumbing in boost gauge available on the net ) this way u can keep an eye on ur boost to hopefully avoid engine damage if u overshoot the standard boost limit by to much and the vac gauge is usefull for diagnostic purposes but u would need to learn how to read the vac gauge properly off the net , vac/ boost gauges also do not show boost when u just rev the car , it will only show vac pressure , it will howevert showboost when u r driving and ACTUALLY boosting properly not like u would be when ur sitting stationary .

lol ma fingers are hurtin lol

johngoulding

iTrader: (7)

cant knock back a free boost guage with free postage unless ur gordon brown

Myles

iTrader: (40)

Christmas came late for someone, good on you mate! Are the WRXs less susceptible to overboost, when compared with the STis?

Myles

iTrader: (40)

He's gone offline! Oh well, if he doesnt want it......you know the rest!

johngoulding

iTrader: (7)

would say theyre just as bad as each other but saying that sti's normally have larger turbos so in that respect i would definately say that in this case the sti's boost spike MAY be higher but due to different ecu's between the two models i would assume the sti's ecu would compensate slightley sumhow ? but not sure on this ? in any case a boost spike's not good at all regardless of what car it is , a boost gauge is mandatory imo to keep check on things . the ones with the alarm that u can set are the best as if ur boosting at 1.1bar and u set them to 1.4 then it will give an alarm when the boost overshoots the preset boost level , minted so maybe u can stick the finger up at the yung 1 in the civic when ur passing him WITHOUT keeping an eye on the gauge after all pml

baldfox

iTrader: (1)

If it's the cost of the remap that's putting you off, have you thought of having an opensource remap ? Does the same as an ecutek, just using a different method of writing the info to the ECU (unless I am wrong ?). I am booked into see Thwaite developments tomorrow.. as I am about to fit a downpipe, fuel pump and new filter (panel). He is charging £350 for just the opensource remap, I thought that was good value. Who knows maybe others charge less. I don't think it's worth the risk to be driving about potentially with something that could in certain circumstances cause the engine to go. You know how quick the scooby comes on boost the chances of catching an error or pulling over in time if something went wrong is going to be pretty slim IMO. Japanese cars maybe relatively bullet proof, but they are not cheap when they go wrong !

Myles

iTrader: (40)

Or.......Dynamix (Racedynamix) who last time I looked were doing a newage remap for £300-350? Look here Subaru ECU Remapping / Tuning @ RaceDynamix | UK | Mobile Subaru Remapping & ECU Tuning

johngoulding

iTrader: (7)

he is right in a sense , but thousands of scooby owners are running a decat without a remap ? its more of a battle of mapped / unmapped the differences are very beneficial when having a map and is by far the best way to go ( think he sed he was going to get it mapped in 2010 which isnt long ) hence why the boost gauge was offered , a spike is very noticable and can be avoided if a boost gauge is present as to visual viewing of the spike IS VERY NOTICABEL as ther is a big red needle that goes higher than its supposed to and the fuel cut would kick in way before the engine gave up IF u were keeping an eye on it until a remap which he plans , running tescos 99 octane or bp's 102 ( very expensive though ) would be a wise choice , super unleaded anyway of whatever make teascos being the highest value and octane for a pound a litre as the higher octane level also helps the engine to withstand diferences in boost levels , det , knock etc

53

iTrader: (41)

TBH with the cat in the uppipe and the cat in the down pipe still in place, removing the tiny second cat on the WRX isn't going to make a huge difference. The panel filter and y pipe will reduce the 'disrupted' air flow and the de-res pipe will make it feel like it's reving more freely. You have nothing to worry about IMHO. If your car boost spikes on that tiny TD04 with the other 2 cats in place then I'm a banana Get the other cats sorted for the remap with a 255 fuel pump and a 3 port boost solenoid and jobs a goodun.

daz1968

iTrader: (13)

I agree with above, won't cause an issue. I had panel filter, ppp y pipe, ppp backbox, ppp centre cat delete and a H&S centre pipe. Had no running issues at all.

johngoulding

iTrader: (7)

i have a FEW 3 PORTED boost solenoids that are from classic models if u want mate all post 1 of them aswell for u with the gauge and that will get u on ur way ? as i said pm me mate.

sum 1 confirm that these solenoids fit on his car ?

Mark'sWRX

+1 (or is it +2?)

dynamix

iTrader: (3)

They will be the wiring harness will need either cutting and re-connecting or the pins pushed out of the 3 port harness and connected that way.

bigarf

iTrader: (67)

i would stick with the answer 53wrx has given,i wouldn't worry at all with the mods that you have done.

johngoulding

iTrader: (7)

well anyway theyre there if any 1 wants to do that as i suppose ur right they would still retain the same function as the newage one ?

johngoulding

iTrader: (7)

pm me if u want m8

H2o-uk

iTrader: (1)

Hi guys, wow lots of information to go on, I hadn't been paying attention this afternoon. JohnGoulding many thanks for your offer of the boost guage etc, but I think what I plan on doing is run the car for a couple of days, as the decat pipe has only been on for about a week and I havent driven it really. I only use VPower in the fuel tank so that should help anyway, but I'll probably remove the decat pipe for the time being and re fit it once I'm ready for a remap. I'm not ready for the remap just yet as I want to get the brakes and handling sorted first of all. Going to get some Ferrodo pads and Whiteline ARB etc and some new tyres. This is all great information by the way folks, many thanks for your responses, it seems there are many opinions on the subject. The background behind all the prodrive gubbings was that I wanted to remap the car well within its thresholds as I use it as my daily driver, and seeing as the car could be supplied with Prodrive Performance Pack I'd pick up as much as I could and then get a third party remap.

Again thanks all keep, your opinions coming.

Myles

iTrader: (40)

If that boost gauge is still going Id be interested, I am running my bug wrx on a partial decat, I have the gauge fitting kit all ready to install and am just looking for a meter to tell me if the mods are causing spikes! Obviously Ill slip some cash your way!