Quick simple question. If i was to upgrade turbos from stock to GT28rs would I also need to make changes to the ECU for it to run well? And.. if I didn't change the ECU, would it still run alright/reasonably until I got proper tune? Thanks
You will be fine. If you aren't changing your injectors then no need to touch the ECU. Just don't boost over 14 psi until you can get a proper tune on dyno.
No friggin' chance..... Not a hope in hell of it starting, let alone running :bash: The injectors needed to adequately supply fuel to the RS turbos will absolutely flood your motor without adjustment to K values & latency And if you are planning on using oem injectors with 28rs's (as Kabir said in his post) you are an idiot and I would suggest you do some research.
Where can i find the relevant information on why not to use OEM injectors with 28rs's? You must have some idea, since you advise not doing it .. I'll probably just end up sticking with stock auto turbo's and use manual exhaust housings..
28RS's will flow enough air to make well over 400rwkw. The standard injectors are barely good enough to do 250rwkw...
You don't need to upgrade injectors to run 28rs's. But what is the point of using them if you can't get anywhere near their potential. Turbo upgrades should be the last thing you do before you open the engine for cams, porting and such. If you haven't got all the bolt ons like bigger intercoolers, full exhaust, intake mods, injectors etc do those first then think about turbos.
Yeah i haven't got all of them bolt on mods yet. But i'm working my way there and do have some of them. Might be a better idea to just take the engine out of the car in the future to upgrade turbos if i feel i need them upgraded. But for now i'll be putting it back in with the stock turbos and focusing on getting all the other bolt-on mods covered with a decent tune to suit. I'd be happy with that I think lol
OK M8, your original question/s above has been pretty much been ignored. Put simply, ASSUMING you are going to run the same boot pressure you are successfully running now, then the short answer is an ear ringing NO changes to ecu and YES it will run happily! It will run EXACTLY as it does now with perhaps increased lag and slow spooling times. NOTHING ELSE. It matters jack even if you mange to fettle on 6 individual T66's, at current boost, it will run JUST FINE. This assumes of course, that the boost pressure IS THE SAME for a single T28 or 6 x T66's or whatever else you can manage to strap onto the engine. Its such an old chestnut that, for the same boost, a higher potential flowing turbo will somehow lunch your engine due to lack of fuel or whatever. See, heres where so many get confused. The ENGINE is a positive displacement end user of air and it alone determines how much CFM travels thru itself, AND the turbo. call it a pressure regulator, if you will! The turbo itself has little influence in the real world at a GIVEN psi regardless of it POTENTIAL to flow a zillion cfm or whatever else. Think of using the stock fuel pump and then fitting a gang of Bosch 044's at STOCK fuel pressure. NOTHING will change as the injectors are the positive displacement end users and any excess POTENTIAL flow will just piss off harmlessly back to the fuel tank. Now, before a discussion erupts on the flow rates of fuel lines versus fuel flow from large pumps, Lets just for a moment try to ignore here the obvious limitations of stock fuel line flow rates for just a minute and assume the lines can carry ANY flow rate (CFM) we give it shall we? The analogy is good enough with a little imagination. The turbo is purely the supplier (just like the fuel pump). The cylinders are the end users (same as injectors) Apart from some minor variations from pumping losses on the turbine side and overall efficiency variations, which will be close to academic at everyday lower boost settings, the engine will still only let *blah* CFM of air thru it at *X* psi at *Y* rpm NO MATTER what POTENTIAL of air supply you throw at it. It makes close as fark is to swearing bugger all difference how you SUPPLY that POTENTIAL air pressure/flow because thats all it is....POTENTIAL. The engine tune, IE: cams, porting and RPM are the factors that determine how much air will go thru at a given psi. A correctly stated by drz400y, fitting up big fark-off turbos, on their own, with unchanged boost pressure will not result in ANYTHING particularly concrete. Well nothing positive anyway. Just most likely some slower spooling and lagginess. Perhaps some slight increases in power (that only a dyno might reveal) due to the turbos eventually running at a better efficiency at some stage in the whole process. BUT, if you want to fit your big-arsed whizzers and keep your boost pressure within limits the current tune supports then go right ahead m8 and feel comfortable that NOTHING bad will ever happen. L8r E
Question was already answered correctly.... If you read the above reply to his question, you'd note that I suggested the injectors needed for the RS turbo would be the reason he couldn't run the stock ECU. A K value of 288 would drown the sparkplugs with 550/740 injectors, and running stock injectors with RS's would be absolute stupidity when you consider that stock turbos already push oem injectors to 90%+ duty cycle.
I am plodding around with 28r turbos and stock injectors ATM. Boost controller off = 12psi. Gave it a squirt yesterday and got to 95% duty won't be doing that again
Yes my friend i read that. And, "IF" he asked about bigger injectors with a stock system then the reply is totally relevant. No argument. However, he DIDNT ask about bigger injectors did he! You told him about it. In fact, he made NO mention of upping the boost or changing any other facet of his fundamental engine tune. I quoted his original question in my first post. He simply asked of he would experience tuning issues if he hit his engine up with GT28's only did he not? So, I gave him a straight answer to his straight question assuming he was NOT upping boost which is the way I interpreted his very simple question. L8r E
"rest your case" How? Magicmike is NOT running stock boost M8. Hes running 12psi which is the setting using HIS wastegate cans. He didnt quote his afr's. They may be so sky high that with some ecu tweaking, he could run 14psi @ 95% duty and 12psi all day every day then all is good no? All discussion should be based on the assumption that everything is going to be stock. 12psi is NOT stock. L8r E
''Upgrade'' is the magic word..... This implies doing the job properly (which would involve the appropriate injectors).
You've been reading the tuning bible Ian! I hope you realise you need to pay royalties to use quotes like that
Exactly! Not much of an answer if you tell them what they want to hear only to set them up for failure without all the relevant information.
That's correct... I rest my case ! My closing statement was MagicMike just illustrated my point. I still stand by that statement because I can't see anyone pulling their motor and bolting on thousands of dollars worth of high performance turbos in order to run standard boost with oem injectors.
thats the worst advice ever kabir.. if hes upgraded to gt2860rs turbos they are going 2 be pushing almost double the amount of volume of air... if he was to boost 14psi on them (equivalent to almost 2 bar on stocks) your engine is going 2 ping it tits off ...... drive it off boost to your tuner. get it tuned.. and at least upgrade your injectors !!!
