Mercedes E55 AMG, rear mount turbo, VGT turbine, Holset HX55, etc etc

Thread in 'Project Cars and Builds Threads' started by Stavros, Oct 19, 2014.

  1. silverzx

    silverzx Member

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    So did you find a compressor map for the turbo (which I doubt exists) and work out all that jazz that I have hardly any understanding of?

    Or was it more of a case of "that one looks f-cking huge and cool, I'll bodge it on". :D :smokin:

    What turbo can get an SR to 400bhp on standard internals then and make chronic cho cho noises and spool by 3,500? :smash:

    For that matter, what about an M50 (more just out of curiosity).

    Edit: No troll.
     
  2. Stavros

    Stavros Active Member

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    The importance of compressor maps is way over exaggerated. Useful, but if you decide on a turbo purely by compressor map, you tend to pick a pretty shit turbo. Unfortunately that's what many do. No comp map available don't discourage me one bit, it's a bonus, not necessity.

    But considering the proven performance of the things I've built, do you really think it's a case of "that one looks f-cking huge and cool, I'll bodge it on" ? No lol. That's closer to what many so called 'experts' do, and still end up with stuff that performs way worse than my 'cheap' setups.

    What you've described on the SR is just the usual GT2871 loads of people bang on them, haven't you? 400bhp on 2ltr with quick spool is always a funny number, a place where there's not many turbos around.
    That 6cm billet HX35 Compressor Racing is selling would do the above though I'd say, and I'd have that over a 2871 personally. But at least a 2871 is a easy bolt on stock stuff turbo, if nothing else.

    And M50, well, HY35, all day long. Bloke on here posted yesterday, even with a stock 12V M20 and a HY35, he had boost from 2k, full boost by 3k, and 370odd at just 1bar, so piss past 400 with a little bit more.
     
    #82 Stavros, Sep 16, 2015
    Last edited: Sep 16, 2015
  3. silverzx

    silverzx Member

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    Fair enough, so if you haven't used a compressor map what/how have you judged the turbo's suitability to the engine? I'm not having a dig or anything just curious of your method. :)

    I quite like the farmer/pikey approach of "ere, 'e looks like a good'un. We caz radge 'e on with tha' welder later tonigh'! 'e gonna blow like a good'un 'e is. Me Grandpappy 'ad one of those holset jobbies on 'is combine until tha' crook Bob wen't go' all mad 'n burnt 'e out of spite!" Seems to of worked to date but I don't think it's the wisest way to spend money now I'm on to more expensive things like SR's.

    The HX35 with 6cm looks snazzy but it's all the money. Can get a brand new HX35W on FacePalm at the moment for £300. Which would then pay for the 740cc injectors and possibly leave £50-100 toward a Nistune. Then again, if I were to go through the ball ache had I might as well spend the extra £300 and just do the job properly with a 6cm HX35 in the first place!

    I have a 325 coupe sat around chilling doing f-all getting an easy life. Maybe I should take this approach on that thing. Could probably radge that £300 HX35W on for around £1500 including all the manifold/external wastegate/exhaust/injectors/ecu/map. Then I don't really like BMW chassis after getting out of a S14...

    I'm gonna drop you a PM.
     
  4. Stavros

    Stavros Active Member

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    Wheel inducer/exducer sizes and housing sizes, combined with experience, will tell you 10 times more than a compressor map will.

    All a compressor map does is tell you what the potential flow/boost that compressor will do, but it tells you literally zero about turbine flow, which is way more important to performance and reliability. Compressor maps are just things people on the internet and certain brands like to talk about. The reality is they're of minor importance unless you totally clueless or are comparing turbos that are almost identical in wheel specs etc etc.

    The farmer way isn't as retarded as you make out from my experience of the mess about farmer tractor pull lot. Some of the stuff they do, while agricultural looking, is 10 times cleverer than all the sheep on here just copying each others shit.
    They're not as stupid as they look.

    A brand new HX35W will be a brand new fake at 300quid, and what size turbine it got? Doubt it's even a 12cm one, and even that's a fucking massive turbo for a SR, so it's basically a terrible choise for 400bhp, esp with a single scroll setup.

    RHD BMWs are a nightmare to get turbo stuff on. And not as cheap as people think.
    3 choices I've seen-
    Shitty adapted eBay mess setups usually found with an eBay turbo on being smashed to fuck at Brum wheels.
    750quid for some awful looking but UK made log manifold that fits and will make power, but is a pretty shockingly poor design from a flow point of view.
    1500odd or whatever Zurawski Motorsport sell theirs for, and is fucking awesome, but it costs money.
     
  5. silverzx

    silverzx Member

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    Interesting stuff! :)

    I'm waiting to find out. Hopefully it's not massive (12cm+) but I'm not holding my breath.

    Don't really want to fork out for the 6cm if I can help it. I have injectors, ECU, mapping, downpipe etc to factor in as well.

    If I could get a suitable Holset for £300-400, 740cc injectors for £150-250 (£300 new), Nistune for £150-200, I already have a top mount, oil lines are cheap enough and a map (£250) I'd be happy (total £850 at best), downpipe and exhaust could be adapted with scrap lying around.

    I have a spare SR lump lying around that I can rebuild should I want to go silly power and then it'll be a case of blow up the stock one and drop the forged one in.

    All seems a bit of a waste though when the shells becoming a bit rough from abuse.

    As for the BMW, I know the RHD's have the issue with the steering column but you'd get around that with a welder and patience. People rely on off the shelf shiz too much.
     
    #85 silverzx, Sep 16, 2015
    Last edited: Sep 16, 2015
  6. Stavros

    Stavros Active Member

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    Even a 12cm HX35 on a SR, unless you got a twin scroll setup, won't be making decent performance until 4.5k+ so it won't be nice to drive. Easy 400+ but a shitty powerband. Proper twinscroll and they do well from 3500 or so, which is mint for a 600bhp turbo, but single scroll even 12cm and that size turbine wheel is a lot for a 2ltr unless you after 500+

    I've seen the BMW issue 1st hand, its a massive massive cunt of a job, hence why it's not common.
     
  7. silverzx

    silverzx Member

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    Oh yeah I'm not saying I'll put a 12cm on the SR I was just saying that's the sort of budget id be looking at. Saying that, if I spent £600 on a 6cm it would probably outlast my interest in high powered cars and probably not depreciate in value too heavily being the 6cm variant.?

    Choices choices....

    Is that right? Was he a farmer? Haha!
     
  8. Andy318ti

    Andy318ti Active Member

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    What a noise.
    Love it.
     
  9. Stavros

    Stavros Active Member

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    Like most standard production cars, off throttle at least, the E55 understeers too much for my liking, so more front grip was in order.

    18in track tyres are pretty pricey to be fair, but then I managed to get a pair of brand new Pirelli tarmac WRC tyres for less than the price of 1x normal track tyre. Nice.

    [​IMG]
     
  10. Stavros

    Stavros Active Member

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    One thing I felt it needed after the last drift day was better response, it spools up fast, I don't mean that, I meant throttle response, not turbo response.

    Turbo cars are never as good as n/a for that unless they got ALS as until the turbo is blowing more air than the engine is sucking, the engine has to suck thru a load of pipework.
    And on this, it's a 5.4ltr engine sucking thru 20ft+ of 60mm pipe, so it's worse than most. In fact you can see the boost pipes trying to suck shut off boost.

    In fact as I've driven these cars without a turbo, I knew it didn't have as much throttle response n off boost power as when N/A, and there was a few occasions on the last drift day that'd come in handy.

    So I had an idea, from something I've seen on some very trick Volvo Penta twincharged 2 stroke boat engines, I could allow the engine to breath like it was N/A, but boost like it was turbo. Best of both worlds.

    So I did...

    [​IMG]
    [​IMG]
    [​IMG]
    [​IMG]

    And it works. Boost comes in at the same rpm (it spooled fast anyhow), zero air leaks as its designed to do what I've done so nothing is changed in that way either, but the instant throttle response is back to being the big 5.4ltr kick in the ass they are when N/A, which is much much better.

    AND it's yet another thing to confuse the fuck out of everyone that sees it with lol.
     
  11. keggy

    keggy Member

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    one way valve? where do you get these?
     
  12. 59bhp

    59bhp Member

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    that's kinda cool, one of those things when you see it you think "dammit why didn't I think of that"

    presumably it would work with mid engine, turbo cars if you wanted to put an intercooler at the front of the car. hmmmmm.
     
  13. Stavros

    Stavros Active Member

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    Can do whatever you want tbf.

    The Momo MR2 Turbo GT300 car in Japan that won the Championship back in the day had a mid-engine, but turbo in the boot, and a massive front mount intercooler.

    Off a Volvo 2stroke twincharged, boat engine.
     
  14. mrtom22

    mrtom22 New Member

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    Now that is cool as fuck! What an awesome idea, cant wait to see this at the next pembrey outing
     
  15. silverzx

    silverzx Member

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    That's cool as fuck man. [emoji106]
     
  16. Sir_Squidalot

    Sir_Squidalot New Member

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    You're like the evil genius of turbos i love it!
     
  17. n1tr0_9

    n1tr0_9 Member

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    Do you have to meter the air coming in? or is it so little it doesnt matter?
     
  18. Stavros

    Stavros Active Member

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    Cheers!

    All the air entering the engine at all times is metered. Nothing has changed there.

    And TBF, a shitload of air is entered via the above, all of it below 2500rpm, so it deffo needs to be known about by the ECU.
     
  19. Sea Squirrel

    Sea Squirrel Jeff Mills Is Watching!

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    That's a really interesting, really clever idea. I assume it's something that's only of use on either twin charged or large displacement engines though? The average drift engine (by that I mean sr or 1jz) isn't going to see much response increase as they don't seem too down on response anyway, or would you expect to see a noticeable difference on any engine Stav?
     
  20. Stavros

    Stavros Active Member

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    Personally I don't think it would be any real advantage on more normal stuff, no.

    Most engines are gutless pre-boost anyhow, run it without any boost pipes, you'll soon see, so it makes no odds.

    And this, due to pipe length being so hugely long due to rear mount, makes it worse than most.

    If it was an engine with lots of grunt without a turbo yes, and only then if it had a lot of inlet plumbing. But that's pretty much zero drift engines.
     

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