Author Topic: Mk1 G40 Turbo  (Read 74863 times)

Offline Yoof

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Re: Mk1 G40 Turbo
« Reply #75 on: May 13, 2014, 09:16:31 am »
Excellent work Ross!


Offline Andy

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Re: Mk1 G40 Turbo
« Reply #76 on: May 13, 2014, 10:53:11 am »
I'm enjoying the quality and attention to detail of this build, lots of effort going into doing the packaging well for the sake of 'doing it right'. Give me this over a slammed bike carb'd AFH'd smooth bay Mk1 any day.

Offline z3i

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Re: Mk1 G40 Turbo
« Reply #77 on: May 13, 2014, 11:42:43 am »
I'm enjoying the quality and attention to detail of this build, lots of effort going into doing the packaging well for the sake of 'doing it right'. Give me this over a slammed bike carb'd AFH'd smooth bay Mk1 any day.

^^^ couldn't have put it better!

Offline Etches

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Re: Mk1 G40 Turbo
« Reply #78 on: May 13, 2014, 12:41:15 pm »
After skimming the update last night, going through it again today. Couldnt agree more with Andy, Ross theres some seriously awesome touches :) man. Exhaust looks stunning too, I'm excited to see the compressor - intercooler pipework now!

Offline Yoof

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Re: Mk1 G40 Turbo
« Reply #79 on: May 13, 2014, 08:29:24 pm »
I'm enjoying the quality and attention to detail of this build, lots of effort going into doing the packaging well for the sake of 'doing it right'. Give me this over a slammed bike carb'd AFH'd smooth bay Mk1 any day.

Shame he likes motorbikes really, otherwise he'd make the perfect husband.


Offline dubstar

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Re: Mk1 G40 Turbo
« Reply #80 on: May 13, 2014, 09:53:44 pm »

Thanks a lot guys, much appreciated. High praise from geezers who really know what they're doing - it doesn't get better than that.

We're function over form types of guys. Engineers! That said, hopefully I can get it to look nice too, but that's more subjective.

Going to do the boost pipework later Tom, I know it'll go in now, so I can do that once it's painted & being built for real. I'm still concerned about heat management, but I'm sure I can sort that side of things.

Pete - didn't know you cared  :D Well, if you own a motorcycle you get pigeon-holed as being a biker. (Actually, if you own a Mini you get pigeon-holed as a mini boff too. I suppose it's the same for everything!!) I'm a car man, not a real biker. It gets me to work, I like riding it and getting through traffic + it's fun and insanely fast if you pin it but cars are my deal - and not just Minis! Small cars with decent power really.

Anyway I'm spoken for.  :-*

Offline dubstar

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Re: Mk1 G40 Turbo
« Reply #81 on: May 18, 2014, 08:19:30 pm »

The thing is, I was going to build both my manifolds in mild steel; and the turbo manifold is. The problem is that to get out of the turbo & down quick enough so I don't hit the radiator, I need some tighter bends. Now as a rule of thumb, if you're mandrel bending tube you can do it to about 1.5 D - that is that the centreline of the bend is one and a half times larger than the diameter of the tube. This isn't tight enough for me. Luckily, I know of a place that presses bend half's which you weld together, at 1 D.

So I got tiggy with it.



I also got a length of tube too, (and some stainless MIG wire) so I was all set to build the downpipe.











Boom. The tricky bits were getting through the ARB with 2.5" pipe and setting up the height & angle going down the car for when I build the rest of the system later. Anyway long story short - I cracked it. It's pretty damn close to the sump but I figure there's a lot of air-flow down there so it'll be rate. After finishing it I realised I had used standard ARB mounts, not the ones which move it forward! D'OH! Hey - that only means more clearance. So I need to weld that up at some point but that's the easy bit. I'll put the lamda boss' in later too.

I took that off and looked it the brace for the turbo manifold to the engine mount and made up some bits....





Then I had a brew and a think. I'm concerned about welding a bracket that close the the turbo flange, as all that heat will make it prone to cracking. It's probably the hottest part of the whole system! So I sacked it off. The other reason I'm concerned is heat transfer through the bracket & mount into the rubber bush. Could melt the whole lot. So if you look at the picture above, there's a cheeky gearbox casing hole next to one of the headers. I'm going to brace the manifold to that instead. I'll do the same with one lower down on the casing for the downpipe. Sorted.

That's it folks - engine back out! I stripped the 'bay and it came out this morning. Since then I've been tidying things up in there now all the expensive stuff is out of the way - it's looking good now.

In other news I also (barring a couple of stitches) finished the work on the bonnet by moving the secondary catch off to one side.



It works a beaut  ;D

Oh, just a few words on the cooling system. I had a couple of rad pipes made up to some templates I knocked up. The hoses are a bit pike-tech but in the face of paying mege-bucks for bespoke silicone ones, using part butchered OE Polo, Citroen & Peugeot pipes coupled with my steel pipes sorted the issue for about £7.50! It's not gucci but it'll work and thats the main thing. With the turbo off you can see it all a bit easier...



Tidy  :)

The list of jobs before paint is getting smaller. Next biggy - Mk3 bulkhead & pedalbox into Mk1 shell.



Offline GR40

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Re: Mk1 G40 Turbo
« Reply #82 on: May 18, 2014, 09:04:53 pm »
Ur manifold and the placement of the turbo worries me! I once had a leaking manifold and the gases escaping and hitting the thermostat housing, where enough to melt the plastic. I am really concerned that the heat from the turbo will melt something. Are u considering heat-wrapping  the turbo housing and downpipe?

Offline Andy

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Re: Mk1 G40 Turbo
« Reply #83 on: May 18, 2014, 09:24:20 pm »
Then I had a brew and a think. I'm concerned about welding a bracket that close the the turbo flange, as all that heat will make it prone to cracking. It's probably the hottest part of the whole system! So I sacked it off. The other reason I'm concerned is heat transfer through the bracket & mount into the rubber bush. Could melt the whole lot. So if you look at the picture above, there's a cheeky gearbox casing hole next to one of the headers. I'm going to brace the manifold to that instead. I'll do the same with one lower down on the casing for the downpipe. Sorted.
Could you brace off the cold side of the turbo onto the gearbox mount too?

Offline oldskoolmat

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Re: Mk1 G40 Turbo
« Reply #84 on: May 18, 2014, 11:53:41 pm »
Looking awesome Ross it's gonna be really special the turbo installation,your wasted on CM

Offline Yoof

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Re: Mk1 G40 Turbo
« Reply #85 on: May 19, 2014, 07:53:52 am »
Perhaps look at bolting a bracket to the turbine inlet studs ontop of the downpipe flange (and nuts).


Offline dubstar

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Re: Mk1 G40 Turbo
« Reply #86 on: May 19, 2014, 07:27:13 pm »
Hey Mat I've got love for your build too!

GR40 - Yeah it worries me a little too and rest assured, I'll be lagging the crap out of everything nearby! I've also got some thin 'stucko' aluminium material to make some heatshields with, which I'll hold into pipes with Terry clips. I'm going for this K03 blanket.....

http://shop.zedperformance.co.uk/index.php?route=product/product&product_id=30

....which I thought was good for the price. It's hard work completely shielding these turbo's with the integral wastegate. I think it'll be ok. I'm under no illusions, heat management is going to be a battle.

Yeah - I'm a little unsure on the turbo mounting too. Manifold is 16swg pipe, so with the turbo inlet and the downpipe both being braced to the 'box casing I was hoping to get away without any more mounts? Not quite with you there Pete - can you explain your thinking a little more please? Cold side might be an option - need to look into it further. I can do that out of the car thankfully.

There's quite a bit of weight in the turbo, which I guess is what you're concerned about?

Offline z3i

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Re: Mk1 G40 Turbo
« Reply #87 on: May 19, 2014, 07:55:25 pm »
Did you tig all off the exhaust?
I need a welder myself and have found a highly rated one (inverter type) it can mig and tig, only ever mig welded myself but by the looks of your work tig is the way to go. its £200 more than a decent mig welder so not sure which to go for
did you get much nicer welds with tig? reckon it would be beneficial to tig body work (non structural) over mig
also thought for when making brackets, it would be good to use stainless metal and tig custom parts opposed to mig
sorry, i know its not related to your build :S
any help/ advice would be much appreciate, is it worth the extra £200 for a tig welder?
Taylor

Offline dubstar

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Re: Mk1 G40 Turbo
« Reply #88 on: May 19, 2014, 08:30:29 pm »
Yo Taylor,

You know the deal - different tools for different jobs. Right from the outset though, don't forget that MIG uses CO2 or 'Argoshield' gas (an Argon mix) but TIG needs pure Argon. Gas (and bottle rental) is expensive unless you go for the throw away small ones.

Mild & Stainless use DC current, so you can use a set without HF (high frequency) for startup - in effect, 'scratch start'. Not brilliant/ideal, but it works. Aluminium uses AC, so to maintain the arc through the phase, you need a set with HF. These tend to be more expensive. If you get one, get one with HF.

Oh, and you need different tungsten's for steel & aluminium too. So TIG can be an expensive deal.

TIG is kind of like gas welding, but with an electrically generated flame. Back in the day before MIG, everything was gas welded together. Then MIG was invented. No-one gas welds cars up now. (Barr brazing for certain processes.) So for bodywork, stick with MIG generally.

Yeah it's cool for brackets & framework in fairness, but the other thing to factor in is that MIG is a hell of a lot easier than TIG. I'm not saying you wouldn't be able to pick it up, but it's a skill.

It's particularly useful in exhausts when welding in pressed bends, as you can tack things together and the tack is flexible so you can change angles. MIG tacks tend to be more brittle in my experience. I'll be MIG welding the rest of my exhaust, but inside the flanges will be TIG with the minimum of filler wire so it's nice & smooth. If you have nice clean edges which meet perfectly, you can use a TIG torch to fuse the metals together without filler wire - which is what I was doing.

That's a long answer isn't it? Stick with MIG unless you're going to do a lot, master a new skill and spend a wad on materials in the process!

Offline z3i

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Re: Mk1 G40 Turbo
« Reply #89 on: May 19, 2014, 09:02:28 pm »
Ah thanks dude!! That was exactly what I was looking for :D appreciate the long answer :P

Been reading all day about them lol, there is no limit on what to buy, but I've found a really decent mig for £350 can weld really low amp for thin stuff and has a proper control panel, so just dial in wire size, metal thickness and sorts the rest out, makes my life easier as a novice