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cammmy

Modifying the Standard Turbo

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Hi Guys

 

Assuming my MS ECU swap goes okay, I'm planning some upgrades after the car is running but before it's fully tuned on the dyno:

 

  • Injectors - Kepping standard 4+2 sequential but using MS to improve control and replacing with new, higher flow units.
  • Chargecooler - Purchase Alunox unit (if group buy goes ahead), connect A/C and chargecooler rads as per Sport 300
  • Turbo - ?

At this stage I want to keep everything as drop in as possible, so looking at modifying the standard unit. There's a UK company that have said it will be around £380 "worst case" to rebuild mine with 360 degree thrust bearings and a billet 60 trim wheel + matching housing. This includes collection, rebuild (including new shaft etc if worn) and return. So cheaper depending on how much is re-usable. I've been told this will support 360BHP as the billet wheel allows for more blade area that a standard super 60.

 

I like this option but have a few questions:

 

Can I leave the turbine standard? Or will some form of modification need to be done to stop it choking due to an increase in exhaust gasses?

 

The standard outlet from the turbine housing doesn't seem to be the best design from reducing turbulence. Is there anything that can be done to improve this? Is there any practical way of separating the flow from the turbine and wastegate for a while? The design doesn't seem to lend itself well to pipe in pipe or tongued downpipes.

 

Will I need to do anything with the wastegate or will I just be able to re-use the standard one?

 

I'm not after every last fraction of HP, but I would like to make the most of what I'm doing.

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Upgrade today to remove Google ads and support TLF.

Cheers, I've read through all of those a few times. I think I'm going to stick with a rebuild and modified compressor but just wondering if anyone has done the same and can answer my questions around the exhaust side.

Edited by cammmy

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Cam

you wont need higher flow injectors with your mods. with my mods, the highest PW is 15ms, 20ms is a standard acceptable limit before needing a higher flow unit.

Welch used to rebuild the stock turbos similarly with great results, though I don't know the specifics of the wheels. if you haven't purchased the manifold yet, you can spec the flange to match any turbo you wish.  you have my (Welch's) turbo part number, ATB can provide a different housing with same or better performance, esp with twin scroll option

since Welch no longer supplies turbos, he may divulge the specifics of his rebuilt stockers if you ask

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Interesting, so you think the standard injectors are good for 360BHP (not that I think i'll reach that)? I just remembered about the fuel pump actually, I'll need to find out what they flow.

 

I thought it was worth upgrading the injectors even if you weren't going for more power? Due to the questionable spray pattern from the standard GM parts?

 

The MS3/X also has the capability to use a flex fuel sensor, so If I need a new pump and injectors, it's no big deal as I'll get ones that are ethanol compatible and do the hoses too. Assuming it won't damage the tanks that is...

Edited by cammmy

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if you are staying with the 4-2 non sequential setup, use injectors of the same flow rate, even if you get new ones.  does the MS3 drive both high and low impedance drivers? If you decide for sequential injection, now is the time to make the changes, not later.

I can send you a part list for the 2 mods you need for sequential, then you need 4x 800 to 840 cc/min injectors and ditch the secondaries.  I purchased five-o motorsports black op injectors (high impedance) which have all stainless internals (for flex fuel) and response times equal to the old peak and hold units.  they market them as having smaller droplet size (always desirable) but narrow cone (engine setup specific what cone size works best)

my mods are not complete so I cant speak intelligently about them yet

 

yes its confirmed from my logs and the local tuners that 750cc/min will support 350 hp (the stock system uses 2x380 cc/min)

I currently am using brand new RC 370 injectors (for sale now) and a Walbro GSS340 pump.

 

you can go to www.injectordynamics.com and click on their fuel flow calculator to get a good idea (there are pics and calcs in my spreadsheet)

rule of thumb is to stay below 80% injector duty cycle at max rpm

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Cheers, my plan is to do this in two stages:

 

1: Get the MS in with as little modification as possible and get the car running as is. Just to verify everything is working.

2: Once the car runs as is, perform the turbo upgrade and any supporting mods that are required. Then dyno tune.

 

I'm planning to stick with staged batch fire as I'd need to add a cam sensor to go sequential? I believe you also need (at the least) to be able to monitor the EGT's on each port to use individual cylinder trim and if not using that, the main benefit is really only around emissions and economy at low RPM. By the time you are approaching high RPM/duty cycle the injectors can't inject all the fuel during a single valve opening?

 

I'm trying to keep it all as drop in as possible as I've never done anything like this, so am being quite cautious. I don't want to take this off the road and get stuck half way through. If I can keep the wiring etc mostly standard initially and only change the ECU at first, I can at least drop the standard back in if I hit issues.

 

The MS can control both high and low impedance injectors.

 

I imagine you would want a wider spray patter for the injectors aiming at the back of the valves but not sure about the secondaries. They point into the plenum rather than down the runners correct? Would you also want a very wide spray pattern there for homogenisation? I'd have thought that if they were pointing down the runners then you would want a narrower pattern?

Edited by cammmy

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As I think you are after 350 - 360 hp, a suggestion for your turbo:

http://www.turbos.bwauto.com/files/pdf/dimensional_reference/efr/EFR%206258-A.pdf

 

Size is 62mm compressor which should be spot on for this HP. (Advertised over 450hp is too optimistic)

And has latest turbine geometry in it which helps spoolup, together with the Tial turbine rotor.

Relatively high compressor efficency keeps comp outlet low. 

Should also be fairly easy to adapt to the car, 

Edited by plumdeplakmuis

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That does look good, quite expensive though at about $1,700 US plus tax from what I can see.

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You need one of these:  http://compturbo.com/products/turbos/ct3

 

You may try calling this company directly  http://compturbo.com/about

 

 They sell and build their own TRIPLEX CERAMIC™ Ball Bearing Turbochargers

http://compturbo.com/spotlights/triplex-ceramic

 

.

Edited by MrDangerUS

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Cheers, I saw those in another thread and had a look. Do you know how much they are?

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It all depends on your individual specs and configuration. If you want v-band, external/internal waste gate, etc, etc. For example the 5356 is designed to have a higher flowing turbine to keep the inlet to back pressure at a close ratio to increase complete turbo efficiency.

 

Just pick one closest to what you need  from this list   http://compturbo.com/products/turbos/ct3

and email Justin at  

[email protected]

to get the quote.

 

I would go for billet  wheel and 3x bearing unit.

Also, I would send them your OE turbine housing and ask to adjust the turbine wheel size to your dimensions.

Beware! OE turbine housing casting is to thin to be ported, therefore wheel has to be bespoke made.

 

To determine parameters of the turbo you want, use this

http://www.turbos.bwauto.com/aftermarket/matchbot.aspx

click on the "Enter match-bot " button and adjust the numbers.

Edited by MrDangerUS

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Thanks, at the moment with everything else I'm spending on the car, forking out for a brand new turbo will probably be a bit much for me, especially if I need other parts to make it work.

 

I've been told under £400 worst case (likely to be cheaper) to have mine rebuilt with the billet 60 trim compressor and it should drop straight back in (if the standard wastegate actuator is up to the job I guess). 350 would be nice but even if I get 300-320, that'll keep me going for quite some time.

 

Eventually I'll look at much fancier parts but right now I'm only doing this as the new ECU will require dyno time, so if there are some cost effective ways to get some more out of the car while I'm already paying for the dyno, I'm all for it.

 

I think it's also good to see what it's possible to do modifying the standard bits, as that's a potentially cheap and easy way of going about things for people who just want a little bit more poke.

Edited by cammmy

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Another option would be to:

 

1. modify your old OE turbine housing by porting it to 56mm and installing a larger wheel. This will significantly reduce the exhaust back pressure

 

2. On the cold side, use "Super 60" Nissan Skyline #19 compressor

 

3. Since adapter ID can not be bored larger (1.9" ID inner pipe doesn't have enough material), you have to chamfer the adapter flange to match it to the larger turbine port. It is not the best solution, but it is the ONLY inexpensive solution available. The other alternative would be to build a new adapter and relocate the waste gate dump port.

 

If you decide to go this way PM me for more details.

post-11050-0-47464200-1431616087.jpg

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post-11050-0-52383700-1431616725.jpg

post-11050-0-39190900-1431618432.jpg

Edited by MrDangerUS

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Cheers, that looks interesting. I don't believe I'll have the issue with the adapter though. Mine has an internal wastegate and centre pipe connects straight to the turbine outlet.

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Which cars have the adapter, and which have internal gates?

 

Aaron

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86/87, 88 Fed and 88 ROW had this adapter. Internal gates came after.

 

From 1980-88, Lotus used the Garrett T3 turbocharger. It has, turbine  .63 a/r,1.80 inducer (46mm), & compressor: .42 a/r, 1.72 inducer

 

Here is the info direct from Mr.Esprit :-
The Turbocharger on the USA Turbos with Bosch K Injection (86, 87 & 88)

are Garrett T3, Lotus Part No. C910E6372F (Listed in Lotus Parts Book)
Specification as follows :-
0.63 A/R Turbine, 1.80 turbine exducer,
0.42 Comp,  1.72 compressor inducer
55 Trim Comp Wheel

T3-5046, .42/.63

      c  t      c/t
Boost set at 7psi (remote waste gate with spacer ring) and 9.5psi without the ring

 

If you're planning a few flow improvements, therefore you need to establish a stock 86-88 OE turbo performance base. There are many maps in this library and you may find out which would be the closest to 1988 X-180 car.     http://www.squirrelpf.com/site/

 

European cars from 88 MY (X180 Intro) had a Garrett T3 with 'Integral Wastegate'.

Lotus Part No. A910E6889F (Listed in Parts Book) (91-93, T0373)
Specification as follows :-
0.63 A/R Turbine
0.42 a/r Compressor
55 Trim Comp Wheel
Boost set at 0.66 Bar

Thanks to Brian Angus for the above info.

Edited by MrDangerUS

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Just wondering what Tranny are you running, that being the weakest link?

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Hi Cam, 

 

Just starting to upgrade the GT3, and create a new turbo set for approx 300hp, among other things needed to make the GT3 more GT3ish

 

Base of the set i will be using is the MHI TD04HL, with 58mm compressor, 

With only minor modifications the turbine-in should be made fit to the manifold, as the MHI unit is very close to a T3 shape flange. Also I much prefer OEM wheels and components over aftermarket stuff, as the OEM aero from new generations is way more efficient than the tuners stuff. (TD04HL 58mm around 77% peak efficiency)

 

Compressor is also straight forward with integrated by-pass valve, 

I will start a new topic in project and restoration room and show some pics of the possible turbo setup. 

 

Would like to hear your approach on the calibration, as I'm not sure which route I will take. 

 

Cheers 

Jaap

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Nice one,definitely interested to see how that progresses.

I'll be tackling the ECU install in a month or so. So far it's tested and seems to be working fine. I've received my new injectors too (the MS3 is easier to use with all high Z injectors).

Will put up a thread when I've got it going.

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Hi All

Just wondering if the turbo is the same as a Cosworth unit? I know it has a cosworth style turbine outlet but does the rest of it match?

I ask as it might make finding uprated turbos a bit easier if we can browse Cosworth suppliers? There seem to be a few companies doing exchange units.

I'll follow up with some Cosworth suppliers after the car is on it's new engine management if no one knows. Could make finding replacements/upgrades a bit easier.

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