merlin71

Hi,

I have a non PPP'd WRX 02. Samco intercooler hoses, middle cat gone for a straight through, Prodrive BB fitted.

Fitted a dawes and boost gauge, stock reading was 1bar.

Currently wondering what i can squeeze out of the turbo without pushing my luck - would the engine cope with 1.2 (17.4psi) or should i settle for 1.1 or maybe 1.15 to be safer?

I always run the car on SUL, not the sort to boot the car to 7k every time i go out, just want that kick when i need it

Many thanks

NickAdams

iTrader: (5)

I know someone who was in a similar situation to you (ie He didn't cane it everywhere he drove!!) who had a Dawes on an 02 WRX and his was pullin 1.2bar boost without any problems.John Banks is probably the best person to answer your question though!!

Good luck

Nick

P.S: Have you not considered an ecutek remap as that's the 'safe' way of running higher boost and having increased fuelling to handle the extra boost!! (Assumin you ain't bothered about warranty that is otherwise it's PPP only)

Spooks

Sorry to kinda highjack this a bit but didnt know you could fit a Dawes to a bugeye?
Kinda curious as to this one myself also, been considering an Ecutek recently but know nowt about em and was wondering what boost etc I would expect, what boost the turbo could cope with.
Look forward to reading the replies
Laters
Spooks

merlin71

Well, i fitted it in 20 mins, absolute doddle. Been tinkering a bit, been running 1.2 dead today, absolutely bloody incredible over stock 1bar, pulls like a train. I disconnected the pipe that led to the boost solenoid thingy - dawes directly inbetween the turbo and w/gate.

No spikes whatsoever, boost tails off 0.1 and holds 1.1 @ 5750/6k.

Very smooth to drive even at 1.2, my Forge DV works well with it too, except its a touch louder now releasing more pressure on gear change.

Ecutek? Hmm, £700 vs £50? I dont think so....

JB - can you comment on what may be safe for a bugeye?

Thanks again.

MadGrip

got me thinking now......


I have an 01 WRX bugeye and my boost gauge is peaking at about 19 psi

is this too much ?

merlin71

MadG - i really dont know mate, maybe it is just a touch too high...but i'm no expert.

I guessed f/cut on my car was about 1.3 and somewhere i read that the car would fuel without any problems at all to 1.2 so thats why i've been running 1.2.

I really cant see the internals having a problem with 1.2 or even 1.3 but what is a concern is heat - you really dont want that turbo getting silly hot. I've only kept and eye on heat from the stock water temp gauge but it isn't showing any change from stock and the car doesn't feel like its overheating one bit. IC is warm to touch like it always is so i dont think i've got any heat probs and i dont put my car on track or anything like that. The samco hoses even feel the same temp as they did before.

Someone help us out here

1.2 safe? 1.3 safe?

MadGrip

would be easier to tell if i wasnt so dumb

what is 1.2 Bar in psi ??

and whit is 19 psi in Bar ??

chris singleton

MY01 PPP decat often peaks at 1.25 in second and third (settles at 1.2) and sometimes peaks at 1.4 in 4th and 5th (settles at about 1.3).

Above figures are when it's cold, obviously slightly lower in this warm weather.

Hope this helps.

Chris

john banks

The turbo and intercooler on the bugeyes are capable of 18ish PSI (1.25 bar) midrange, and you can hold it quite a lot at the top too (as long as you have no cats in the system).

The limit is detonation. You should have a knocklink.

Don't mix up a (capable) boost controller and an ECU map, they have some overlap in function but they are a completely different kettle of fish.

The advantages of a remap are that:
- you can remove the excessive fuel that you don't need when the cats are removed leading to more power and torque
- you can increase the amount the ECU will advance the timing, liberating further power and torque as octane allows
- you can map the boost by throttle position giving a smoother ride and ensuring the ECU is open loop and the fuel pump is on full capacity when there is boost
- the ECU can still drop the boost in response to uncontrollable knock that doesn't respond to fuel or timing changes (e.g something goes wrong with the fuelling system). It can also limit the boost in other fault situations to preserve the engine. It will also limit the boost on a high speed run to prevent detonation at high speed on continuous full power

With a Dawes only you imitating the PPP (even then rather badly because you don't have part throttle or RPM based control like the PPP does) for the MY01 that Prodrive stopped using on the later models in favour of an Ecutek remap.

I love Dawes devices, but they have limitations and caveats on their use like all add ons.

merlin71

Excellent, thanks JB.

I think im going to stick to my 1.2bar and just continue to be sensible with it (i.e keep away from 7k and no prelonged 150 mph blasts on the motorway).

Will keep an eye on boost too, colder weather is just round the corner.

One point though - i dont have any part throttle full boost issues, used a 1.5mm bleed hole on the shoulder of the dawes and it drives like boost and revs are perfectly balanced.

Thnx again.

john banks

It doesn't have to be full boost on part throttle. The MY99/00 ECU fuels better on part throttle than the bugeyes one which has a variable fuel pump duty and can be closed loop to a larger throttle opening. This could heat up the combustion chamber considerably even if it doesn't det. 8 PSI at 14.7:1 mixture could be damaging. I don't know anyone that has tested a Dawes properly on a bugeyes to know, from the look of the ECU fuelling tables I don't like the sound of it personally.

It is not going to det at 7000 RPM, more likely to det at 4000-5000 RPM.

[Edited by john banks - 8/20/2003 12:19:36 PM]

merlin71

Ok, so if this was/is a problem with the bugeye's - am i right in saying it would still be a problem irrelevant of what boost level the dawes was set to? If so then i'll invest in an AFR meter , if not then i'll happily stick to what i've got now.

Meantime and for some peace of mind - if the car was running lean to the extent it could cause damage - would we see the CEL light up? I'd be happy if i knew there was some kind of safety for us Dawes/Bugeye people without AFR Meters.

Thanks again...

merlin71

Another quick question -

Is running lean more likely to occur in a fully decatted car?

Mine has only the centre cat replaced straight through - the DP and U.Pipe are stock, just wondering whether that has any relevance at all...?

john banks

Yes. If you use a bleed valve it would probably be safer, but it is not something I have tested.

No

Yes, it is more likely to make more boost on part throttle

Yes you could melt the uppipe cat from high exhaust gas temperatures. Bits would then go flying into your turbo which could cause it to go out of balance and the spit bits of compressor wheel through your intercooler and into your engine. This has happened on some US cars with manual boost controllers.

I am always a miserable doomsayer, but has anyone properly tested a Dawes on a bugeye?

I did thorough testing on decat 99/00 and checked:

EGT, charge temperature, AFR, knock, injector duty cycle and power/torque.

The areas of concern are EGT and AFR on part throttle and injector duty cycle on full throttle.

There is a known issue with bugeyes running the fuel pump too slow and sticking to closed loop (14.7:1) until quite impressive throttle openings. The older cars were much keener to go open loop, and the input from the throttle sensor to open loop fuelling is small, so they got away with it with a bleed hole over 1.0 mm.

In addition, many have found that after a few days or so the performance drops considerably, the ECU likes to thrown in fuel and retard timing when it hits areas of the map that are not supposed to be trodden.

[Edited by john banks - 8/20/2003 5:08:16 PM]

merlin71

Well, 1stly, thanks JB for the tech info, after carefull consideration i've decided i've got the ***** to stick with my dawes - but to keep temps down i think i'll back off 1.2 bar a little - maybe 1.1 or 1.15.

found this thread :-

http://www.scoobynet.co.uk/bbs/thread.asp?ThreadID=72225&ForumName=Drivetrain&For umID=11

The guy seems to have been reporting similar egtemps with the dawes fitted and did report a little lean running light throttle when turbo was coming into play. I really struggle to drive in such a way where i use a light throttle and let revs build up to a level where turbo starts to spool anyway so no overly worried tbh.

I'd guess the US guys who blew their cars were running some stupid *** levels of boost or caning their cars at the time...

Rest assured ill report back if i send my turbo into orbit...



Thanks again.

Ru$$Rip

As a test I put a dawes on my 02 wrx and kept with a Tek3'd fully decat 01+ WRX to 100 mph :O . For 50 quid you cant go wrong (compared with a 700 quid Tek3). For me personally It was great and provided that you dont go over 6k and 1.2bar in 5th is quite SAFE. My wife drives the car %90 of the time so I just leave it off.

[Edited by Ru$$Rip - 8/20/2003 9:52:12 PM]

john banks

RRH tested UP TO 1.1 bar and found lean issues on part throttle. It is a bad way to modify a car if you have to drive around it and avoid part throttle situations. What about the next long motorway hill you go up at 1/3 throttle?

Ru$$Rip there are many ways you can go wrong blindly fitting a boost controller. Yes you are blind if you were not monitoring for detonation, EGT and AFR? What were your injectors doing? This is a cheap way to blow up your engine if you get it wrong. I am not saying you will, but by the same token that people have got away with it for a certain time does not mean that they will continue to do so or others will. Did you keep up with the Tek 3 car before it was mapped properly or after? I kept up with a Ferrari 360 on my standard engine running 1.75 bar but it certainly proves nothing about it holding together, it just proves it went rather quickly for a while and may or may not have continued to do so

I love Dawes devices where they are used properly, but who has really documented their proper use on a new age car? It is all assumption. There are key differences on part throttle with the fuel pump duty and huge areas of closed loop operation on the new age cars. A Dawes increases the boost significantly in zones where the fuel pump is not on full duty cycle and the fuelling is closed loop. That is dangerous IMHO.

Not running it at high boost at 6000 RPM is no real defence against blowing an engine, neither is not caning it everywhere. Interestingly a lot of people use a lot more part throttle than they realise.

You would be safer on a MY01 running a bleed valve or adjustable restrictor or actuator adjustment and a fuel cut raiser, along with a knocklink and boost gauge. This will have no part throttle high boost issues whatsoever, and can be set to raise say 2 PSI across the whole rev range.

HKS FCD is under £100, you still have a fuel cut. There are then easy methods of raising the boost as above - never looked to see if MY01+ have adjustable actuator but that is the obvious method. Still needs knock monitoring though, but you could do away with EGT if there is no part throttle frisky boost.

If there is not part throttle frisky boost with a Dawes that is because you have made it into a bleed valve by drilling out the hole too much. At 1.5mm it is not actually that far off a bleed valve, at 2.0mm it is basically a bleed valve.

[Edited by john banks - 8/20/2003 10:12:41 PM]

merlin71

I was thinking about the bleed hole - if i did make that 2mm - would that postpone turbo spool up a little?

If somehow i could delay turbo spool up - to a point a little later in the rev range, that would help to avoid the danger of lean running on part throttle. Ok, it wouldnt be a rock solid solution but if it worked it would be a hell of a lot safer than current set up.

john banks

You may as well run a cheaper fixed restrictor valve in place of the Dawes. They are about £7.

It is not so much that things are delayed very much at all, spool up would probably be barely 100 RPM later, more that the restriction is fixed, so at part throttle there will be some linearity.

merlin71

Gotcha,

Last questions - any idea where i can source one from and also - would i keep the existing pipework and just plumb it in where the dawes is curently?

I presume i still keep the hose that went to the boost solenoid disconnected and blocked off so ECU still has no control over boost?

Ta.

john banks

Flow control valve replacing restrictor

Except you wire it without the factory boost controller - ie inline like a Dawes.

[Edited by john banks - 8/21/2003 9:38:41 AM]

merlin71

J - having some probs finding the part(s) at Festo - but i found this:-

http://www.mardibloke.co.uk/Cars/Lotus_Elan_M100/Upgrades/Rob-C_Boost_Controller/rob-c_boost_controller.html

and the parts this guy specifies are available next day so i'm just about to order 2 x 1/4 hose tails and 1 x 1/4 restrictor.

Sorry for pestering but to me this looks like it will do the job nicely, does it look ok to you? I'm not fussed about a few £ difference in price.

Soon to be 1 x Dawes For sale....

merlin71

oops, i mean i'll order 1/8th not 1/4.

merlin71

ordered 1/8th, stuff will be on my doorstep tomorrow.

Ru$$Rip

As you know a TEK 3 is only as good as the mapper and Yes my car ALWAYS ran well with a dawes on. And YES a delta dash was used to monitor for det EGT's etc. Each time with NO issues. Thats not to say that other people will not have problems though.

Turbo_Steve

And if those problems are a blown engine....?

A Remap is ALWAYS safer than an MBC.

To those guys running a Dawes....FFS buy a knocklink!! IT's easy to fit, it only costs £150 or so and could save you £3000 of engine rebuild. You want more power? You have to PAY for more power.