Kenny_Powers

iTrader: (1)

Hi Tidgy

Is the crossover line not normal then? Sorry, I don't really know how to get any info from the graph other than the obvious.

Here is a better upload of the graph so that people can see it the right way up!

Tidgy

cross over point is a constant, roughly 5250 ish, so with it being down at 4500 something doesnt look right. Unless im missing somethign with the way its displayed.

dave_t

iTrader: (1)

"I am planning on a VF43 and Sti top mount intercooler and Y pipe next."

If your planning on this anyway get it done then a Duncan remap

Kenny_Powers

iTrader: (1)

Yeah, I think that's what I'm gonna do Dave. Just have to find a decent second hand VF43 now cos I don't really want to fork out over a grand for a new one. I also want to sell my standard hawk WRX 17" alloys to help fund my further adventures, and cos they are taking up space in my small garage, so I better take some pics and put a post in the relevant forum!

Kenny_Powers

iTrader: (1)

Morning folks. I think I have found out what the problem is. Driving down the A48 last night with my window open a bit, I could hear a fairly loud hissing noise, which started being noticeable at about 4000 rpm, exactly the point where my torque starts to abruptly drop off. I never noticed it before as the exhaust is so loud. So I'm thinking that I must have an air leak somewhere. Now I just need to find out where. I'm thinking that the first place to check is the intercooler y pipe? I know that Prodrive fit a different y pipe when they instal the PPP. Is this because the standard WRX y pipe is unreliable above standard boost levels? Also, the intercooler would have been removed when my downpipe was fitted so maybe they didn't do a clip up properly or something? I don't really know as am new to forced induction. What do you guys think, would the system being unable to hold the pressure properly above 4000 rpm cause my graph to look like it does?

Cheers

GazJenno

Surely with the scales being different for power and torque the cross over point wont follow the normal trend. The torque scale in lbft goes up to 350 on the right and the bhp goes up to 300 on the left.

Tidgy

yeah tis a fair point, graph just looks strange

Kenny_Powers

iTrader: (1)

Ok, I am now 100% sure my lack of power problem is being caused by a boost pressure leak. Just went for a drive....2nd gear....hit 4000 rpm.....loud hissing and car hesitates for about a second.....hissing suddenly stops and car shoots forward pinning me to my seat. So now I'm thinking, what could be intermitantly leaking? Could it be the dump valve, which is the standard recirc BTW?

Tidgy

doubt thats it mate, pressure woudl make it leak worse not suddenly stop leaking. Sounds like it needs looking at

Infected by sti

iTrader: (6)

Imho bud if your loosing boost at 4k then it should be consistent through the rev range as the higher the rev range the harder your engine is working so to me it doesn't make sense for it to hiss or make a noise up until that point and then take off.

You may hear the turbo starting to spool but at 4k turbo should be fully on song and going for gold.

At 1.2 bar your standard recirc should be more than capable of holding boost, I wouldn't automatically rule it out but I'd say it was unlikely tbh.

Have you got a boost gauge in the car to see what's happening with regards to the boost when it happens?

Kenny_Powers

iTrader: (1)

It defo seems like high pressure air coming out somewhere, it sounds just like air coming out of a blower on an air compressor hose. I am gonna give Anthony at Indigo GT a call

Kenny_Powers

iTrader: (1)

Sorry I maybe didn't explain it very well. The hissing noise doesn't start low down and then stop at 4k rpm, the car takes off as it should from under 2k rpm, then it gets to 4k and the hissing noise suddenly starts, as though whatever is causing the problem can take the pressure up to 4k. The car will then hesitate for a fraction of a second and then the noise will stop and power comes back on. How hard i accelerate also affects this issue, if I put my foot down slowly and smoothly it doesn't seem to happen but if I slam my foot to the floor it is more likely to happen .

From 1500 rpm you can hear the turbo spooling and it continues to spin faster as the revs climb, as it should. This hissing noise is separate to the normal spooling sound.

I haven't got a boost gauge but am going to try and get one this weekend so that I can see what's going on with the pressure.

Kenny_Powers

iTrader: (1)

Well, last night I finally got around to whipping my intercooler off, and found a battered looking Y pipe underneath. There is what looks like a small hole with an oily patch round it, which I'm hoping is the cause of my troubles. Here's a couple of pics










The pipe is wrapped in some kind of rubber heat shrink, with foam and insulation tape around it. Is this normal, or does it look like a previous repair? The standard Y pipes I have seen for sale on eBay don't have all this stuff round them.

Anyway, I have ordered a new pipe assembly, which I will fit tomorrow. Fingers crossed it's going to sort my issues out!

BrownPantsRacing

iTrader: (6)

Standard Y pipes have foam on them from factory. Mine didn't look quote as abused with tape though.

If I were you i'd upgrade the Y pipes to silicone type as they hold boost better and don't colapse.

Kenny_Powers

iTrader: (1)

That's what I have ordered mate. It should arrive tomorrow.

I was really happy to see how battered mine looked when I removed it, as it's given me a lot of hope that the pipe is where the issue is!

If all is good when the new one is fitted then the car will be going in for a map tweak!

BrownPantsRacing

iTrader: (6)

Good plan that man!

Kenny_Powers

iTrader: (1)

Well, the new pipe assembly arrived. I got it from a company called Race Spec Performace for £47 delivered, and it seems to be decent quality. Anyone else have one of these fitted?

If I have time I will fit it tonight and then hopefully that will be the end of this thread! Well no, hopefully the end of this thread will be me posting that my car is now making 290/350!

Kenny_Powers

iTrader: (1)

And.....it didn't frikkin fit! Well that's the risk you take buying stuff off eBay. Will now be sending this back and buying a full Samco turbo hose kit.

It seems that the 2.5 WRX has a different intercooler to the 2 litre.

BrownPantsRacing

iTrader: (6)

It does. plastic 2.5 WRX intercooler is different to previous WRX versions. Actually flows slightly better than old WRX intercoolers so i'm told. I changed mine to STI intercooler years back.

Kenny_Powers

iTrader: (1)

Bit of a delayed reply here lol, been busy with things other than my car. Now I know that I need a specific pipe for a hawk WRX, I'm going to just fork out and buy a Samco silicone turbo hose kit. In the meantime, I've had to put the crappy hard plastic Y-pipes back on. The clips were very loose when I took the intercooler off, so I made sure that I did them up tight this time, and I have to say, just doing that has noticeably improved the cars performance.

BrownPantsRacing

iTrader: (6)

If you ever upgrade to an STI intercooler I did a lot of measuring & research to find suitable Samco hoses. Can give you individual part numbers that will save you lots of money over the Samco intercooler kits!

Kenny_Powers

iTrader: (1)

Thanks mate. I may actually see if I can find an STI intercooler and just go straight down that route, rather than spending £120 on a set of WRX hoses only to have to buy more if I upgrade later on.

BrownPantsRacing

iTrader: (6)

If you do get an STI intercooler you must also get the newage STI scoop under tray. May be worse than the WRX one with a mismatched scoop duct and intercooler.

Kenny_Powers

iTrader: (1)

Ah ok, thanks. While we are on the subject then, will the bonnet scoop from a blob STI fit in to my bonnet, and do hawk and blob STI's use the same intercooler? Cheers.

BrownPantsRacing

iTrader: (6)

Won't need to change your bonnet scoop, just the under tray to a newage STI one. It will fit inside your standard scoop and fit to the STI intercooler exactly!

All newage STI intercoolers fit all newage WRX's and any STI scoop under tray will fit any WRX or STI scoop. Also any newage scoop will fit and newage bonnet hole.

The only exception I was told was that hawk WRX's and STI's have a drive by wire throttle so use a different intercooler. Have also found this to be rubbish as I have a Spec C STI (non-drive by wire) intercooler fitted to my drive by wire 06 wrx.

Kenny_Powers

iTrader: (1)

That's great info, thanks. Nothing worse than buying parts that turn out not to fit! The reason I asked about the scoop though, is because I really like the larger design scoop fitted to the blob STI's, I just wasn't sure if the bonnet hole was the same.

There is loads of stuff I really wanna buy, and I want it all now!! But... I had to fork out for the summer holiday for me and my wife and son last night. The only time I could do it for is frikkin August bank holiday week which was a real wallet buster, so any more major mods are gonna have to wait a bit longer. For now though, I'm sure I can stretch to a second hand intercooler, some nice Samco hoses, and a boost guage!

I have another question if ya don't mind...if I get someone other than Indigo to tweak my map, will I have to pay for a full remap, minus licence fee of course? If I take it back to Indigo then I will only be looking at £100 for an hour of tweaking, but I wouldn't mind having someone else try this time. Duncan of Racedynamix or Bob Rawle are the two people who have been most highly recommended to me.

BrownPantsRacing

iTrader: (6)

I know your pain with family expense & kids! lol.

Best to check with Duncan or Bob on costs, but I would say almost certainly you would be paying for a 1st map cost of theirs as they will effectively build a brand new map for your car. If it has ecutek license already it may be different. Not sure.

Andy

Pigman149

iTrader: (1)

Is this high pressure noise you are hearing not just your boost solenoid venting off to allow more boost before the waste gate opens ????????

dynamix

iTrader: (3)

Kenny... Pm me if you want a price but I'd be happy to take a peek at it assuming i am in the area for a small fee but it would only be fair to indigo to give them another chance Imo and most probably cheaper too. If you did want another full map (i would start afresh on it) then by all means give me a shout.

i hope you get it sorted soon or at least looked at by a Subaru mapper as internet diagnosis tends to lead you down a winding and very expensive path in my experience.

Kenny_Powers

iTrader: (1)

Hmm, I don't think so, It's another noise separate to that. But as Duncan has said in the above post I could be here a long time without getting anywhere, as it's impossible to know for sure without looking at the car. I've got a Samco hose kit on order so will fit that and then have the car looked at properly.

Duncan- I'm gonna pm you mate. Cheers.