Scoobynodd

iTrader: (1)

Hi all,

I have an unmolestered and VERY standard 2004 blobeye with very low miles.

Before I start doing all the major/more fun mods I'm wanting to do all the less exciting supporting/safety mods such as the symmetrical fuel line mod (with fuel. reg) better fuel pump (walbro) inlet manifold heatproof spacers, bov and so on. Amongst all these I'm wanting to fit an external wastegate (probably 38mm v-band) which will be attached to a new up-pipe and subsequently remove the pre-cat.

My first question is; I know I'm going to need to make the existing wastegate (on the turbo itself) permanently shut. Can anyone tell me the best way of doing this. I've heard of some folks fabricating up a bracket but I'm not sure how this works. And I'd rather not weld anything on the turbo becasue the unit has so few miles on it, it would be good to either keep as a spare (once I've upgraded) or sell it on.

My second question is; in order for the external wastegate to operate I believe I'm going to need a different boost solenoid (a 4-port one?) can someone fill me in on this and tell me where's best to get one from and which one to go for.

And lastly; do I really need to re-map to fit it? (yes I do know that I'd need to re-map in order to get the benefit of removing the pre-cat) as I'm not playing around with boost levels or upping power yet, and I'd rather not re-map until much later, once I've completed the other bits mentioned above, plus the rest of the exhaust system (btw I'm aiming on keeping the 2nd cat), changed injectors, fitted fmic and different turbo.

To clarify, my aim at the mo with this (viewing only as a safety mod and early support mod) is simply to be able to vent the hot exhaust gas pre-turbo and out thru a screamer pipe. And as a plus so that come higher boost/bigger turbo time, the external WG is already covered. And no, I'm not really looking to go rotated turbo, but we'll see.

Thanks in advance for your thoughts guys,

Nod

stevebt

iTrader: (8)

You don't need an external wastegate and I doubt you ever will?? You will only really need one if you want to run really big power! I think on a standard car you are a million miles away from an external wastegate

Splitpin

Before we go any further, can you clarify what your ultimate aims are? As things stand this external WG idea sounds like a complete blind alley.

There's no point at all doing it on a regular Subaru-type turbo, and the logic of doing it as a "future supporting" mod is also flawed. This is primarily because anything you'd do now to suit your standard exhaust manifold and turbo would almost certainly need to be chucked if you upgrade in future.

If you're thinking of a big power turbo that needs an external WG, you will almost certainly be looking at a custom manifold and downpipe, whether you go for rotated or standard location. Time to think about it is then, not now.

Scoobynodd

iTrader: (1)

Stevebt:

Granted, external wastegates are considered to be more for larger turbos (and they're also for just turbos that don't have their own, which there are a lot of!), but at this early stage I'm only thinking along the lines of disabling the onboard wastegate and setting an external one. Also the external wastgate is situated prior to the turbo itself, this has the advantage of being to vent the portion of the exhaust gas that is to be vented before it reaches the turbo, thusly reducing temperatures slightly, which is never a bad thing, even though we are only talking very marginal! It is becasue of this that external wastegates are a better method than onboard ones. And that is my thinking, nothing more complicate than that.
And Ste, it is standard at the moment yes, so I am a "million miles away" ...at the moment. But read up and read on, you maaay have missed my angle. As I said, there is a lot of little supporting and safer-running mods that I'm doing now as the first part of the upgrading, if you see what I mean

Maybe what I should have made apparent in my first post, is the fact that I actually already have an un-used 38mm v-band to make use of (that I've had lying around for a couple years that was bought for a turbo conversion on a B18-powered civic coupe that didn't get used due to a change of plan) and hoping someone won't say no, use a 44! I've just got a replacement stainless up-pipe that I'm going to mod to fit the wastegate to.

Splitpin:
Manifolds?! I'm not planning on modifying any manifolds. As The only 'modified' item will be the up-pipe. All I'm going to doing to that is fitting (cutting a hole then welding)a mounting flange on a short bit of stainless tube for the wastegate approx. 8" from the turbo-end of the up-pipe.

As for being flawed aren't external wastegates in general are a better idea? The next turbo going on will be a slightly (but not stupidly-so!) larger turbo that probably won't have it's own wastegate which I'm thinking inturn will give me even more options of turbochargers to consider. Come that time, wastegate is already installed.

So will it be the worst thing in the world ever to make use of this external wg? If there are a few folks that think it might be worth a shot (even if it is considered a bit excessive, "against purist-tradition" or whatever) could you give me some pointers to what I raised in post 1. Or is it a case of it'll be more hassle than its worth, as I was put under the impression it wouldn't be, provided we have the right spring it and it's done propperly.

If not I'll just sell the flippin thing!

Splitpin

It's so marginal on your standard setup that it ain't worth the hassle and expense. The cartridge is water-cooled and it's not like the EGT's will be high enough that a "slight" reduction would be a significant benefit. By the time you add up the costs and time involved, all for no quantifiable gain, it literally doesn't add up.

Yeah, I'd got that and my response was written accordingly.

The point I was making is that if you go to a turbo at some point in future that needs an external WG, you will almost certainly find that it will require (or at least benefit from) a non-standard manifold and/or up-pipe. Therefore your existing manifold plus any custom up-pipe you'd made to support your current turbo won't fit the new one, knackering the logic of doing this as a supporting mod to some future turbo of unknown size and performance potential.

The advantages only really kick in when you're talking about very big turbos capable of shifting a significant amount of air - so not where you're at at the moment. And by way of illustration, the various marks of Impreza WRC all run internally gated turbos, and if it's good enough for that application...

This doesn't make sense. Firstly, most of the turbos you're likely to be considering will be internal gate and the standard Subaru mounting pattern. Under those circumstances, the optimal approach would be to use the one on the turbo. Secondly, if you do go for something without its own WG, it'll most likely have a non-standard footprint and thus your existing uppipe and gate won't fit anyway.

Correct.

mr_D

iTrader: (12)

i say do it all!! everyone is constantly saying dont do it. do this,

its your car! if you got the plans and skills, then make it. nothing wrong with doing what you want. you seem technically minded enough to be able to complete this and many other tasks.

if we all listened to ppl telling us no then modifiying cars and engines would never have started in the first place!

dunx

iTrader: (3)

A bigger turbo that fits will have an integral WG for sure, if it doesn't fit, you need custom pipework anyway....

Technological cul-de-sac.... interesting but futile.

If you want to make a silly noise to annoy your neighbours, just buy a stupidly loud exhaust.

dunx

P.S. just pull the hose off the standard actuator and re-map to suit the new 3-port solenoid....

stevebt

iTrader: (8)

I personally think there is better ways to waste your cash than on something that will have no real benefit over an internally gated turbo!

dunx

iTrader: (3)

It makes a "cool" noise on the high street.... with it's screamer pipe
?

dunx

stevebt

iTrader: (8)

I wish I had rid of my screamer pipe as it scares the **** out of people on boost But new pipes are about £1k so I'm not that desperate to get rid of it.

petedotuk

I would agree thats it more hassle than its worth.
But also agree that its nice to break the mold and try your own thing.
If you do it you will almost certainly have to throw away everything you have done when it comes to upgrading the turbo, especially as the only real external WG turbos are not "bolt ons"

A perrin 3-port boost solenoid from TSLcanbe setup to run with an EWG.

stevebt

iTrader: (8)

I use the apexi boost solenoid with mine as its a quality item

Splitpin

The OP posted here asking for advice. He's got some. If he wants to go ahead anyway, he can do at any point, but at least now he goes in with realistic expectations.

Eh? Where did you get that idea? Nobody on this thread has said "Don't modify your engine". What has been said is that this particular idea is a bad one, and that, by implication, there are ways to spend the equivalent amount of time, money and effort that will have a much more beneficial effect on the car.

Scoobynodd

iTrader: (1)

First off folks, I have to apologise - the clamps on this external wastegate are not v-band. My mistake.

Dunx - shurrup ya plonker lol!
...I'm certainly not "pigeon-hunting" if that's what your getting at (to anybody not sure of what I'm getting at search the term 'external wastegate' and you'll find a rather amusing thread about thier related sound effects), I'm 29, not 19 LOL!
I'll meet you half way though - I did appreciate the sound my SSQV made on my old '96 GC8. I actually kept the bov, I'm currently searching for the correct adaptor flange to fit it to the blob - only found them in the US so far.

Funny you should mention that one Steve, when it came around to ECU time I was thinking Apexi.

Mr_D,
Your not wrong - I'm actually a contract Civil and Structural Draughtsman by trade, so I do like to get into the nitty gritty of things

Splitpin,
Now for crying out loud don't get me wrong! - I really am appreciating your imput on this, I am!
...But what I'm not appreciating is the attitude along with it! - tried de-caf?
Plus did I not use word such as 'slight' and 'very marginal' drop in temperature when referring to the finer points of external wg's? I didn't say significant, nor did I hint that the benefits would be awesome! Can we all not try tone down the criticism and be a bit more constructive? I say again, I already have these parts - I'm simply trying to guage their merit - if i can use something without having to discard/sell, and IF it won't blow my car up.
We are on here at the end of the day becasue we like our cars and do you know what, there's even a risk we came on here to all learn from each other too, without actually having to get cocky about it.
I'm guessing your a mechanic sunshine? - See? We can both be sarky.

OK then gang, maybe getting a little bit more specific then...
Furture turbo-wise I'm thinking gt30ish (as, I maybe wrong but I think a 35 would be a touch much, but as always I am open-minded).
Now Splitpin is ded-on, what I'd not been taking any notice of at all thus far, is the fact that the up-pipe connection to turbo is quite subaru-specific, and I'm doubting a gt30 (again for example) will come with a scoob-shaped connection, so if this was to go ahead I'd need a different up-pipe later. But this one I have only set me back £40. And I'm fairly sure my welder guy ain't gonna break my bank fabbing me up a more specific one later, so there's one little headache to sort come time to swap the snail over.

One thing I've noticed tho folks, is that nobody as yet has responded to my main concearn of weather or not I'd be talking a re-map, just to set this up? Or is just a case of being sure of the correct spring within the wastegate, disabling the original wastegate, and having a suitable solenoid set-up correctly? With it being done at such an early stage, this would obviously have an impact on its proceding or mothballing.

Petedotuk
Thanks for that buddy, it is nice to break the mold a little once in a while, but only if I can deem it feasable. So far I'm hoping the only thing I have to be aware of is the likely difference in flange-pattern at the top of the up-pipe come swap time.

mr_D

iTrader: (12)

i know. but its always going to be full of "dont do thi, dont do that", i would like to see it done!! but i admit i know there is more he could do but someone wants to try something different.



[/quote]Eh? Where did you get that idea? Nobody on this thread has said "Don't modify your engine". What has been said is that this particular idea is a bad one, and that, by implication, there are ways to spend the equivalent amount of time, money and effort that will have a much more beneficial effect on the car.[/quote]

i was speaking about the whole site. someone wants to try something different and everyone says dont do it. if its not something original then no one wants to know. thats my impression of being on here! (and please dont start preeching "if you dont like it then leave" cos im not saying that). just think ppl should be more open minded

stevebt

iTrader: (8)

It will definately require a remap as you need totally different turbo setup!


As for the gt30r vs the gt35r I think the gt35r is the better turbo but if you got one of those the pipework you would of got custom ade for your car now will not work! I personally would not even go rotated as there is that many quality turbos around in standard position that will do 500/550bhp.

Scoobynodd

iTrader: (1)

Are we 100% on this Steve, are we not just swapping the duty of one wastegate to another? I hope I don't seem like I'm arguing, I'm just asking lol.

That's why I thought the 35 would be o.t.t. as I really don't want to go rotated (even though it is slightly more asthetically pleasing under the bonnet lol) even come turbo swap time, but I was fairly certain I could get a gt30 to fit in standard location - again yes even though it would mean a different up-pipe.

stevebt

iTrader: (8)

gt30 standard position turbo isn't a very good turbo in my opinion! I doubt there will be much resale on the turbo you mod for external wastegate as its sort of specialised and its wether people will trust your modded turbo

Scoobynodd

iTrader: (1)

Ohh that's a shame, why do you consider it a bad turbo fella? I've heard some good things about them, but maybe I've been looking in the wrong areas then (?)

As for my existing unit, I'm not looking to modify it all, if could be helped. I've heard of people fabricating little brackets that somehow bolt the thing shut, although I've yet to see one installed. However Grimmspeed provide the correct bracket for your specific turbo if you notify them upon ordering their external wastegate up-pipes. Very Expensive items tho:-

GrimmSpeed

stevebt

iTrader: (8)

They never seem to make the figures people were wanting/expecting and I'm pretty sure the new MD range is far superior to those

Splitpin

No attitude included dude. I write concisely and accurately and don't pepper my posts with emoticons. Sometimes the written word doesn't convey inflection properly, as I'm sure you know. Any emphasis is to make sure the right point gets made, no more or less.

I didn't assume that you did - but wanted there to be no doubt that the time and effort on this one is likely to generate zero net benefit to the way your car works. As far as I'm concerned this is constructive criticism in that you're getting the opportunity to make a level-headed decision, and possibly reassign the time and effort somewhere more beneficial. As mentioned before, if you want to go for it anyway, that's always your option, but at least you do so with your eyes open.

Way off, I'm in a line of work that requires me to know the difference between your and you're. Must try harder.

It's not just the design of the mating areas. It's the fact that the pipework diameters need to be optimised to the turbo and type of response you want. An up-pipe that's perfect for a TD04, for example, will be way too small for a 450bhp turbo.

You'd ideally use a completely new exhaust manifold, not just the up-pipe.

Had written it in a previous post but must have deleted for brevity. The dynamics of the boost control will be altered, it's all a question of degree and one that it's impossible for any of us to forecast. You may find that remapping might prove to be a quicker, more effective way of bringing it under optimal control than an extended process of trial and error trying to get the wastegate to match the existing boost control in the ECU.

Scoobynodd

iTrader: (1)

Ahh bummer, I was becomming quite fond of the idea of a GT30 too. I'll look into that one some more then. The MD range? I've not heard of these, can you tell me a little more about then - who manufacture those Steve? (I've got a sudden feeling that I've asked another stupid question lol)

Splitpin,
....GORDON ....BENNET

(to the remainder of the scoobynet community and any others whom I may have offended by means of my blatant abuse of our own written language>>), I whole-heartedly apologise for the age-old favourite your/you're slur. Pointing the blame (in true British construction industry fashion) entirely to the fact that I currently find myself in a vocation that (fingers crossed that it's flippin temporary!) has me doing 72 and sometimes 84 hours before chance of a day off and is leaving me somewhat drained. Credit for this goes partly to our beloved Mr. Brown and more so to the current economic state.

....It's horrible at the mo, it really is. I know of an Architect currently driving the home delivery vans for ASDA for example!

So Splitpin, you say that your (did I get it right that time, dear?) profession require's you to observe the correct usage of the afore mentioned written English language, correct? It must also therefore, be the same profession that robs you of the ability to monitor and self-check your (what about there?) attitude when typing a reply. I genuinely don't think you're understanding at what I'm getting at buddy. Now again this is me personally, but whenever I write a reply or a letter I always do it in a fashion that I know beyond shadow of a doubt cannot be taken the wrong way and I always try (at least I hope I do) to make sure and check myself that I'm not unintentionally upsetting anyone. Put simply - nobody likes a smartarse! I've read a lot of your contributions to date Splitpin and don't for a second doubt your knowlege or ability, but you do always seem to reply to folk in a down-your-nose kind of fashion, have they in someway upset you as there own level of knowlege and understanding is below yours so you have deemed them not worthy of equal respect (or something or other).

Sorry all, rant over. In general I am a tad wound up (work and such) at the mo and again I apologise if I have brought down the atmosphere, it's very wrong of me to bring it to the forum. <<looks at shoes>>

But re-touching again on the subject of manifolds and up-pipes...
I don't believe to date I have seen any overly-specially design manifolds for the fitting of GT30r units or 35s for that matter! I have on the other hand seen many a fancy looking up-pipe and some associated bracketry.
I've seen some smoother flowing and better designed (over the factory item) manifolds, but none knocked up for a specific snail!
Up-pipes on the other hand - I've seen some right wonderfully crackers looking inventions, in all kinds of girths, right upto 4"! But a lot of these ones have overcome the more tricky part of special manifolds by simply reducing in diameter before they hit the flange.

Anyways, as I've said, I'm not looking to re-invent the wheel or necessarily do something that hasn't been before - I'm sneaky like that - I let others be the guinea pigs lol.

Again Steve, damn shame about the GT30 is it really that bad a unit? I'm not looking for enormous figures mind, this is going to remain a daily driver and if at all possible I'm only aiming for a reliable say 350-375 bhp. I just want to bomb-proof everything at the same time.

Well, it's a lookin like a dead end and something mothball for later maybe, as I don't want to be mapping and re-mapping at the current costs of maps these days (and I thought my job was a licence to print money lol - no offense to Si and the guys, hehe).

Nod.

stevebt

iTrader: (8)

For 370bhp the obvius choice would be either td0518g, td0520g or md321h. the 1st 2 being the cheaper option.

Scoobynodd

iTrader: (1)

Thanks there Steve, that's really helpful. I'll look into those. Wasn't it a td05 that would have been the factory item on my old (UK) '96 GC8?, only it had the awkward 90 degree vertical inlet?
(or was it a td04)

My I ask which snail your using to get 500? Is 500 considered still reliable - I'm guessing it would be a touch much for a daily driver? + Extensive internal work too, maybe a closed deck block? Must be a heck of car tho!

bluenose172

iTrader: (2)

It might have been better to explain your goals, i.e power, at the start. It's not complicated to get an 03-05 STi to that power level, I think you're trying to over compliacte it. Panel Filter, fuel pump, fully decatted exhaust, remap and a TD0520G would be my preference. I wouldn't bother changing the IC either.

petedotuk

If thats all the power your after I would recommend the MD321H over any of the TD's. The TD's do get the results but the entire MD range is superior to any TD and most other bolt ons out there imo.

You can get the MD's from Lateral Performance Ltd | Home

Scoobynodd

iTrader: (1)

I didn't list full end-of-day intentions, quite simply because (as explained) I've got an external wastegate hanging around checking if gravity is working in the garage and was wondering if I could make use of it yet, mothball it or sell it.

But yeah, maybe it was an ar*e-about way of asking, I just didn't think it would have got this pedantic! And the only thing that's really stopped me doing it just yet is the fact that I'd have to re-map just to set it up, and I couldn't justify blowing circa 300 notes on a map just for that one change.

I'll just stick to doing the wheels (btw, got some nice Rota's on the way, gang), handling and exhaust for the mo, plus I still need to de-tango. Hopefully that won't cause any cafuffle (lol, he sez).

Splitpin

Chap, you're the one making an issue of something here, maybe it's you who needs to lay off the coffee? As explained previously there was no attitude in my posts, up until the point that you, by your own admission, tried to be "sarky".

If you were going to take the thread in that direction, it seemed perfectly reasonable to lob it back over the net. If you can't take it, maybe you shouldn't give it?

stevebt

iTrader: (8)

My turbo is a rotated gt35r running 2.2bar of boost and its probably running around 580bhp now and soon to be a bit more There is a lot of cash in my car and its been a total waste But there is always a need to chase power and it should never be fed as it empties your wallet very quickly I think my car is fine s a daily driver as its the person behind the wheel who decides how fast it goes but if you do decide to push it and you don't have your wits about you it will ave you

Scoobynodd

iTrader: (1)

Splitpin before judge (maybe that's too harsh a word) assume what I can and can't take, allow me to point out my current un-fortunate vocation places me in situations where it get's 'dished to me' by professionals fella!

So I assure I can more than take it lol! And what's more, I did not at all intend to set out to give it either!

I responded to you in the manner that I did (not in my first response to you, because I thought no, lets see how is next time around), but after your second reply, simply because I felt on a very genuine level that you were doing so in a very unnecessarily arrogant (again, sorry if that's too strong a word <<see how paranoid I am with you now, getting the hint yet?) manner. And now I'm convinced you've taken more of offensive with this than I did!

See, with my other profession when contracts and projects have gone belly-up and go to litigation, we have to go through all the relavant correspondance from all parties concerned (including ourselves!) with a fine tooth come taking very careful note of the kind of words and attitude used so as not to make the situation any worse and to cover our backs of course. Now, if you're telling me that you honestly did mean at all to seem that way then I do indeed massively apologise. But that is how your responses have come across to me.

<<looks at plate with large slice of humble pie>>

I'm not a big coffee fan tbh, especially if I made it - my coffee is nasty (work that one out! - coffee's flippin easier to make!), so I stick to tea.

Anyway, k sera