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opticaltrigger

[race_prep] Turbo Hill Climb Project

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jackherer

Is there anything stopping you connecting the coil outputs together with a diode on each wire so they don't backfeed to each other?

 

That's how people wire up the tacho when fitting a GTI6 engine into 205s as they have four individual coil packs.

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opticaltrigger

I did'nt know that that was what was done and to be honest I had not even thought of it that way either.I do think that will work to so I'm gona try it first as it's much easier to try that than wire in the couplers.

Thanks for the tip jackherer,I guess that provided the diodes face the correct way it should work.I will try it and let you know how it goes.

 

All the best

O.T.

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opticaltrigger

Work on the car has been painfully slow the last several weeks due to the ongoing battle we all have...Money!!!.Anyway a few things have happened while it's been slow.

The fuel pump is installed in the new tank and appart from some straps it's all in and ready to go.Still got to make the lid for the tank box though.

Rich has been putting his fiberglass skills to work and built a scoop for the area above the intercooler and the hunt is on at the moment for a suitable buldge for above the turbo which belive it or not (I did'nt) does just miss the bonnet but it's way to close and would result in trashed paint.Might have to also use a turbo blanket aswell but we'll see.

Anyway a few more pictures.

 

All the very best

O.T.

 

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Edited by opticaltrigger

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opticaltrigger

A little bit has been hapening over the last few weeks with the car so I thought I would put a few pics up of it.

Just got the car back from the body shop about a week ago and still in the process of cleaning and putting it back together again.

It amazes me still how despite your best efforts overspray will find it's way everyware.Still most of it was confined to the undercaridge and it's gone now,just a dusty interior to take care of now.

The lexan window kit still hasent arived yet but D.T. has promissed it will be here next week.Incidently,I've never bought a one of these window kits before,I've allways made my own but out of interest does anyone know if they are normally drilled with holes around the perimiter or are they usualy desighned to fit in the standard rubbers?

 

Hope to start thinking about dealing with the engine plumbing next and then we can finally look to starting it up.

 

All the best O.T.

 

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iamjackiechan

I've been playing with the idea of sticking my exhaust out of the front bumper aswell due to awkward routing to the back, but after seeing yours I think it looks pretty good and may consider doing it.

Are you going to have any silencers in it?

Will be interesting to see how loud it is as I would rather not run a silencer.

 

Cheers

Will

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opticaltrigger

We had the same concerns over routing to the back aswell but the real reason is that I just think it looks good there.

 

As far as goes noise,I really cant say untill we fire it up,but my guess is that it will be pretty loud.

The pipe has been made without any silencing at all it just drops down out of the turbine housing and out.Having said that though we have left enough room for a short absorbtion type muffler if needed.I can definatley see us ending up with two pipes.One for MOT and one for race.Turbos do actualy do a quite good job of silencing on there own though belive it or not.

 

All the best O.T.

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Tom Fenton
Turbos do actualy do a quite good job of silencing on there own though belive it or not.

 

"Not"

 

My turbo 205 with a TWIN box system still makes an absolute racket when on boost. Not so bad off boost but still loud.

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iamjackiechan

Ive always heard that turbos do provide some silencing and when my engine was in the 106 previously it only had a tiny silencer with not much baffeling and that wasnt too loud

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opticaltrigger

Dont get me wrong here,turbos do provide some silencing but in comparison to a factory silencing system it's still very loud.

When I say that they do quite a good job of silencing,Im talking from the point of my experience with dragsters using a purely open exhaust verses one with a turbo in the way.And in that case,yes they do provide a silencing effect.

 

With turbos however it could quite reasonably be said that the sound is simply a different one giving the illusion of a silencing effect but personaly I feel it's a mixture of the two.

The pressure wave traveling down the primary pipe from the header to the turbine obviously posseses a greater degree of energy as it's produced by a larger charge as opposed to a normaly asspirated system.As the gas expands across the turbine wheel a very great deal of the energy it carries is taken up by the wheel there by leaving less to be liberated in the form of sound energy.However as boost increases and the exhaust energy goes up a point is reached very quickly in the turbine where the wheel cannot take up anymore of the gas energy due to it's own inherent efficiency limitations.Then the remaing gas energy can only be liberated in the form of heat and sound.Because this efficiency limit of the turbine comes around very quickly you get the rapid increase in volume as the engine moves into boost which in turn also rapidly begins to level off as the efficiency limitations of both engine and turbo are reached.

 

All the best O.T.

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opticaltrigger

Hi all,

It's been an age since I last put anything up but nothing had been hapening with the car as I had been away for some time and the car had been put away due to the bad winter.But it's great to be back on it geting stuff done and moving on again.

The car's only been back out of storage for about 10 days or so but we've had a few bits and bobs turn up which has allowed us to get on,not to much but at least it's some progress.

All in all in the last three or four days we've had the external wastegate,dump valve,exhaust wrap,oil filler tank,and tube for the wastegate turn up and we've got the wastegate mounted so far.

Packaging all this stuff in the engine bay is now starting to become a seperate disipline in it's own right.A real challenge.

Had a great and informative chat with an ignition lead guru at a great little company in Cornwall the other day about the leads that we need to have made for the coils to the plugs.It's always great when you get the chance to talk with somone who realy knows there stuff like that.

 

Anyway here's just a few pics of the wastegate instalation as it's going in.Im going to take the whole exhaust to the machine shop in the week and have the flange faces flatened just to be sure we dont get any leaks then at last get the thing wraped up and back on.It's becoming very repetitive work,taking that exhaust off and putting it back on again.

 

All the best

O.T.

 

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opticaltrigger

Rich has been busy with the welder again and done a great job of finishing the exhaust system off,it's all completley welded up and ready to be flatened and wraped up finaly.There's also been a few more heat shields fabricated in areas which look ike they might get hot especialy the area behind the engine just in front of the fire wall where the exhaust gets very close.

The replacment AFM has been fixed in and a few support brackets finished for the turbo.Oh! yeah got a great little tank for use as an oil filler point.It was'nt straightforward though as the tank was twice as long as needed so we cut it down by half,re-drilled and tapped the holes and replaced the end cap.Now it's got about the right clearence for the pipe to clear the alternator.

 

Anyway here's a few pics of the exhaust and finished tank.

All the best O.T.

 

The new heat shields and much better looking throtle body

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The new oil filler tank after having been shortened

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About here looks good for it.

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Edited by opticaltrigger

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opticaltrigger

The oil tank went on today which is another little job out of the way and as a double bonus the bracket which holds it also acts as a clamp against the steel core plug thats pressed in the end of the inlet manifold.I cant honestley say if it would eventualy blow out under boost or not but it definatley cant now.

It's just so much more of a cleaner way of filling it with oil.From the filler tank we can now run a couple of lines to an oil catch tank plus the one from the top of the cam cover and I think that should give us enough breathing capacity.

My thinking behind it is that most of the heavier oil vapour in the crankcase gases that come up the filler tube will drop out of suspension in the filler tank and the pressure pulses can then be passed into the catch tank.We'll see how it works out but the theory sounds ok I think and hopefully it wont give any problems.

 

Anyway just a few photos of the oil filler tank in it's new place and just for the sake of it a couple of the newly painted bonnet with it's air intake.

 

All the best O.T.

 

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Stolton

WOW :o this is impressive, looks like alot of hard work and lots of time has gone into this, well impressed tho. :)

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opticaltrigger

Hi Stolton thanks for the reply.

Yeh,your right it has been alot of work and in sight of two years now since we started it but we're at the stage now where it's looking very close to compleation and we're geting a bit nervous and excited now because start up day is only two oil pipes and some silicone hoses away.But that wont be the end of it though.

And we've yet to see how the ignition system works out to.

 

I have no idea what it will sound like,I really dont.All I can say is that the sound will be a different one because so much has changed including the shape of the combustion chambers,the C.R.,as well as the exhaust system.We will see soon enough.

 

All the best O.T.

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wicked

Dont get me wrong here,turbos do provide some silencing but in comparison to a factory silencing system it's still very loud.

When I say that they do quite a good job of silencing,Im talking from the point of my experience with dragsters using a purely open exhaust verses one with a turbo in the way.And in that case,yes they do provide a silencing effect.

 

With turbos however it could quite reasonably be said that the sound is simply a different one giving the illusion of a silencing effect but personaly I feel it's a mixture of the two.

The pressure wave traveling down the primary pipe from the header to the turbine obviously posseses a greater degree of energy as it's produced by a larger charge as opposed to a normaly asspirated system.As the gas expands across the turbine wheel a very great deal of the energy it carries is taken up by the wheel there by leaving less to be liberated in the form of sound energy.However as boost increases and the exhaust energy goes up a point is reached very quickly in the turbine where the wheel cannot take up anymore of the gas energy due to it's own inherent efficiency limitations.Then the remaing gas energy can only be liberated in the form of heat and sound.Because this efficiency limit of the turbine comes around very quickly you get the rapid increase in volume as the engine moves into boost which in turn also rapidly begins to level off as the efficiency limitations of both engine and turbo are reached.

 

All the best O.T.

 

 

The amount of energy taken from the exhaust is relative to the CFM's pumped by the compressor.... So max energy is taken at max boost.

But I think you overlook the small detail that your wastegate opens and the exhaust gasses bypass your 'silencer' and enter directly the downpipe.

So there won't be any silencer at full boost.... *recommends a pair of ear plugs*

 

BTW: Respect for the build and doing things you own way, although I have serious doubts about the lag, given the large manifold with this relative small turbo...

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opticaltrigger

The amount of energy taken from the exhaust is relative to the CFM's pumped by the compressor.... So max energy is taken at max boost.

But I think you overlook the small detail that your wastegate opens and the exhaust gasses bypass your 'silencer' and enter directly the downpipe.

So there won't be any silencer at full boost.... *recommends a pair of ear plugs*

 

BTW: Respect for the build and doing things you own way, although I have serious doubts about the lag, given the large manifold with this relative small turbo...

 

Hi Wicked,and thanks for the reply.

I think in some kind of a way we are actually agreeing with each other here on most of the points you mentioned.

Although one thing there is no silencer at all.But finding out the volume level should be fun all the same.

 

With respect to your thoughts on the wastegate Wicked.When the wastegate opens at full boost I do expect there to be a momentary spike in the sound coming out but as you say,it's worst point will be at full boost but that situation will decay almost instantly as full boost will be lost upon the wastegate opening.

As for your thoughts on lag from the manifold size verses the turbo size,all I can say is I personally don't think it will be an issue but having said that I can see how you get to it though.But I really do think the turbo is going to manage ok.

The good thing here is that we will get to find all this stuff out and get the opportunity to rectify it as time and testing progresses.With a project like this it would be unthinkable to not have all kinds of problems crop up.

I have to say the one area that I do have concerns over is the fueling of it and until it gets put under load I really cant be happy.

Anyway the next few weeks will tell allot I'm sure.

 

All the best and thanks again

O.T.

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wicked

I think the sound at boost will be similar to a screamer pipe... Some people like it.. <_<

 

Wrt to the manifold; you'll get boost with that turbo, no problem, but each time you change gears, it will have to fill the manifold again with pressure before you have boost again and experience lag...

And a turbo lag is anoying it there is no good reason to have it (like for big turbo's B) ) ...

 

.. but in the end a turbo with lag is more fun than no turbo at all :P

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Tom Fenton

steel core plug thats pressed in the end of the inlet manifold.I cant honestley say if it would eventualy blow out under boost or not but it definatley cant now.

 

Tested OK to 1.5 bar on my car.

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opticaltrigger

Tested OK to 1.5 bar on my car.

 

Thanks Tom,that does give me some peace of mind as I'm not going to use that much boost,at least not for a while anyway.

 

Had one of those weeks where not alot's happened as we have had to wait for bits to be delivered (e-bay...Just the best for parts).However today we got the battery cables delivered with some really nice solder on lugs and also another tank for the cooling system.So,the weekend should bring somore progress in the electrical department as we will be able to do some testing and checks on all the standard stuff and possibly even take the plugs out and spin up the motor to get some oil pressure up.

Got the exhaust system all off again today and I'm gonna run by the engineering shop tomorrow and see if I can talk him into flattening off the flange faces for us and then finally we can get the heat wrap applied to the thing and back on again.In between all that I'm also going to strip down the turbo this week and do a final cleanup and re-thread a couple of holes before that Finlay goes back on.

 

Anyway,hopefully somore pictures of a bit of progress at the weekend.

All the best

O.T.

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opticaltrigger

As I'm sure everyone is aware it takes an age to achieve anything with this sort of work but we are getting there.

Had quite a bit of progress the last few days with the exhaust system.I took it over to the machine shop and got the flange faces flattened.I still don't know how he managed to hold on to the down pipe in the mill,all he would say is that he had earned his dosh.

Still,it came out really nice and he only had to pull 3 thou out of it to get it flat which got rid of some worries we had regarding alignment of it all.

The most satisfying part was finally getting the heat wrap applied because it's just an awful job and it's done and out of the way now.We've double wrapped the primary pipe from the header to the turbo and both the pipes have then been over wrapped with stainless wire to try and give the wrap a bit of longevity.

 

On the electrical side of things,the battery box has gone in and the battery cables have all been wired in,we went for 35mm2 cables which are quite thick and heavy but I think because of the long run (about six meters on the positive) it's necessary to offset any voltage drop problems on cranking.

We still need to connect up the isolator switches but the cable is all in.

 

Anyway some pictures of the wrapped exhaust and battery box.

All the best O.T.

 

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Edited by opticaltrigger

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opticaltrigger

Hi all,

We've had somore progress on the car again this last few days or so.Lots of those annoying little jobs that you cant see but you know are there have been getting done which is good.But the main progress has been in the engine and electrical departments.The wiring is almost complete now,well at least to the point where some final testing of the ignition wiring can be done and then all being well it can all be tidied up and strapped in place.

 

It's always great when the good bits start turning up like silicone hoses and the like.We had a bunch of stuff turn up a few days ago and eagerly got to work with it all.The main turbo air pipes have with a bit of a row all gone in except for the one directly from the compressor to the ally pipe and a little 1" 90 that we need for the dump valve connection just up from the throttle body.There getting ordered on Friday along with a few other bits of silicone hose for the oil filler tank to engine block and the turbo oil return to sump.

 

The header tank is a work in progress as you can see but the principal behind it's sound.It started life as an ebay power steering tank for a skyline and is steadily undergoing a transformation into a header tank.The biggest headache with it has for a while been how to solve the problem of not having a pressure relief cap for it,but a quick trip to the local hydraulics shop and we managed to track down a really nice little PRV which is at the other end to the pressure gauge.

 

Anyway Here's a few pics of the engine in it's latest guise and one of the work in progress on the header tank.

All the best O.T.

 

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TT205

Looking good mate

 

Bonnet scoop?

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rallyeash

looks good, i havent read through the whole thread but why choose a top mount i/c?

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opticaltrigger

Thanks TT205.There is a couple of photos of the bonnet scoop a few pages back.

 

Thanks also Rallyeash.Well now you have raised a subject there with the I/C,I did get pulled up on it a few pages back by a few guys and I must say for good reasons to,mainly to do with potential heat soak problems.

I cant really give a specific reason for it being up top to be honest,only that it's kind of developed that way as the projects moved along.We do have some concerns over the potential of heat soak etc but to be honest it's very,very low down on the worry list.Some of the bigger concerns we have are more centered around on boost fueling and under bonnet temperatures,and that kind of stuff really requires real word running in order to see how it pans out for real.

As problems and issues crop up (and they will) we plan to just address them one at a time and work through them,hopefully learning something along the way.

 

Thanks again guys and all the best

O.T.

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petert
.....and under bonnet temperatures,and that kind of stuff really requires real word running in order to see how it pans out for real.

 

 

Why don't you use 0.5mm stainless sheet rather than 2mm aluminium tread plate for heat shields? Stainless is a very poor conductor of heat (and electricity), whilst aluminium is near the top!

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