Wez Posted May 22, 2006 Share Posted May 22, 2006 Didnt read the whole thread but if you are running your turbos in the efficiency range they were designed too then they should not be heating up the air, therefore no need for a large FMIC which will raise engine temps by blocking the rad. I run with a CW SMIC and if you look on supraforums in the road racing section most of them are using SMICs with singles too. Also pressure is different from volume, a single large turbo will have greater air volume for the same pressure, for example if you have a 1ltr and 2ltr bottle of coke and presurise them both to 1 BAR the 2ltr bottle contains more air. Quote Link to comment Share on other sites More sharing options...
Miguel Posted May 22, 2006 Share Posted May 22, 2006 Also pressure is different from volume, a single large turbo will have greater air volume for the same pressure, for example if you have a 1ltr and 2ltr bottle of coke and presurise them both to 1 BAR the 2ltr bottle contains more air. So the question still stands. Taking turbo choice and boost run . At what point will an SMIC be outflowed " become a restriction" for the amount of volume a single can move ???? Quote Link to comment Share on other sites More sharing options...
Dragonball Posted May 22, 2006 Share Posted May 22, 2006 Loads of science here http://www.gnttype.org/techarea/turbo/intercooler.html Re-read this a few times - the bottom equation works all the info through 'stock v uprated' ...oh and pressure drop too Quote Link to comment Share on other sites More sharing options...
Wez Posted May 22, 2006 Share Posted May 22, 2006 I would say a small efficient core with a turbo thats running in the correct range is better than a large heatsink, just my opinion On my next mapping session I will datalog the inlet temps if I remember, only prob weather is shite at the moment so not been able to do any for a while, deff need dry roads Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted May 22, 2006 Share Posted May 22, 2006 So the question still stands. Taking turbo choice and boost run . At what point will an SMIC be outflowed " become a restriction" for the amount of volume a single can move ???? Amen Mig!!! Finally, someone thinking the same as me. I can say this cos ive experience surge, DUE to small intercooler and associated pipework on a good sized single. Quote Link to comment Share on other sites More sharing options...
Miguel Posted May 22, 2006 Share Posted May 22, 2006 Amen Mig!!! Finally, someone thinking the same as me. I can say this cos ive experience surge, DUE to small intercooler and associated pipework on a good sized single. Read through the Thread U , I have been sugesting/asking it it near all of my posts. :cool: Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted May 22, 2006 Share Posted May 22, 2006 just read it now, Yea bud Im with ya on that one. Micheal has proved stock cant support single, and I/you have proved a small FMIC(half the size of the normal core Blitz,HKS ones)(so forget poxy sidemounts, lol) are a restriction on big turbos. Quote Link to comment Share on other sites More sharing options...
BURT Posted May 22, 2006 Share Posted May 22, 2006 I'm sure i read somwhere that the smic is only rated for 450 bhp max Quote Link to comment Share on other sites More sharing options...
chilli Posted May 22, 2006 Share Posted May 22, 2006 so at the end of the day it's a flow problem not a cooling one? so what about an uprated SMIC, still too small? Quote Link to comment Share on other sites More sharing options...
BURT Posted May 22, 2006 Share Posted May 22, 2006 would have thought so.. it is still the same size and could only cool the same volume of air as a stock smic Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted May 22, 2006 Share Posted May 22, 2006 Bud, bigger Comp housing, bigger outlet, higher boost, more volume of air is moved,the bigger volume causes the air to get less heated up during compression(as there is more space available for the molecules to expand,inturn making the charge cooler= denser) thus the" bigger turbos less boot more power" saying. at the end of the day, its volume(displacement) of parts that affect Heat transfer and charge density. you reach a certain amount of deisgn flow limit of the core, the pipework, mass flow rate through a tube,etc. blah If i had a GT42R blowing a SMIC, lol, it would surge the crap out of it, and end up hurting my comp blades. and sptting them out the casing. lol Quote Link to comment Share on other sites More sharing options...
BURT Posted May 22, 2006 Share Posted May 22, 2006 thats my point ... an uprated smic will be no more efficient than a stock one? Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted May 22, 2006 Share Posted May 22, 2006 Agreed. No SMIC will flow effiecntly enough for a Big single, and if it does, the cooling capacity will be rubbish, so not point. All IMO, but if you can put a 74mm+ turbo on a smic and have it not surge, and have the charge temps of a FMIC, then youll prove me wrong. Quote Link to comment Share on other sites More sharing options...
BURT Posted May 22, 2006 Share Posted May 22, 2006 Agreed. No SMIC will flow effiecntly enough for a Big single, and if it does, the cooling capacity will be rubbish, so not point. All IMO, but if you can put a 74mm+ turbo on a smic and have it not surge, and have the charge temps of a FMIC, then youll prove me wrong. Quote Link to comment Share on other sites More sharing options...
TLicense Posted May 22, 2006 Author Share Posted May 22, 2006 So to sum up, The issue is that the volume of air is too vast for the SMIC to effectively cool it. Even if it could then you would suffer from compressor surge from having too much of a restriction. Every day a school day, and all that.... OK, temps is easy to measure. How do I know if I have compressor surge? Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted May 22, 2006 Share Posted May 22, 2006 T, I could my comp surge at part throttle condtions. Were talking off boost. It was like a tiny little muted dump valve everytime you let off the throttle the slightest. At WOT, sooner or later it will chuch the blade. Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted May 22, 2006 Share Posted May 22, 2006 T, I could my comp surge at part throttle condtions. Were talking off boost. It was like a tiny little muted dump valve everytime you let off the throttle the slightest. At WOT, sooner or later it will chuck the blade. Quote Link to comment Share on other sites More sharing options...
Angarak Posted May 22, 2006 Share Posted May 22, 2006 Interesting article on stock SMIC and airflow design: http://www.max-boost.co.uk/max-boost/intake/intercooler_2JZGTE.htm Quote Link to comment Share on other sites More sharing options...
jason m Posted May 23, 2006 Share Posted May 23, 2006 I have a CW side mount and plan to go single at some point (if my girlfriend gets her new job ) So any opinions Mig/Usman/Anyone on how big a single a smic will support? 61? 67? Ta Quote Link to comment Share on other sites More sharing options...
Gamer Posted May 23, 2006 Share Posted May 23, 2006 I have a CW side mount and plan to go single at some point (if my girlfriend gets her new job ) So any opinions Mig/Usman/Anyone on how big a single a smic will support? 61? 67? Ta The opinion of an 'Anyone' I would say no more then a 61... Personally I would not run any single on the stock size side mount as I do not like to cut corners. No sure on the price of the CW side mount. I would assume that a somewhat OK FMIC can be had for slightly more then the CW offering. Possibly even one off eBay if money is tight. Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted May 23, 2006 Share Posted May 23, 2006 Jason, if you read my post above bro, if i wa surgeing on a 74 with a .81, on stock motor bar cams with a small FMIC on part throttle, if you go on a 61 itd have to be low boost, as i reacon at 1.4bar+ you might start to run into probs. 67 at above 1 bar i dont think so mate. LOL Does CW run a big single on his GTS? Does he have SMIC on it? CW? Quote Link to comment Share on other sites More sharing options...
Thorin Posted May 23, 2006 Share Posted May 23, 2006 ...I'd be interested in Chris' take on this as well. Quote Link to comment Share on other sites More sharing options...
Kranz Posted May 23, 2006 Share Posted May 23, 2006 I know this has been done to death, but here's my take on it. From what I can recall from my past job. Forget (mostly) about pressure. What we need to be thinking about is mass air flow. The engine will consume as much air as can be forced into it. However the more air squeezed into the cylinders the more resistance to flow there is, like exhaust back pressure. The more resistance there is the more the turbo will have to work to produce the pressure that the wastegate demands. The harder the turbo works the hotter the air gets, and so the lower the total mass of air going through as its density is lower. If you swap to a bigger turbo that can supply air at the required boost more efficiently then it won't heat up as much, so there will be more mass flow. However, if the restrction that was causing the stock turbos to have to work their guts out to produce the pressure is still there, then the improvement that could be gained by the new turbo could be lost. This is because there is now more mass flow at the same pressure. If this extra flow has to go through the same torturous route then the losses are going to be greater (in terms of pressure drop across the restriction) than with the stock turbos. This will, again, make the turbo work harder to maintain the pressure, restrict the mass flow and also cause the turbo to heat the air up more..... which the intercooler won't be able to loose if its too small. Best way to check the difference is stick a MAF meter on the intake & measure the flow (Normally 0 to 5V linear) and then swap the IC to the FMIC and watch the readings change for the same boost levels. Quote Link to comment Share on other sites More sharing options...
michael Posted May 23, 2006 Share Posted May 23, 2006 An FMIC looks cool.... don't forget that Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 23, 2006 Share Posted May 23, 2006 If a single turbo is sized correctly and the ecu is properly mapped my uprated SMIC is fine. Surge usually (always?) occurs at low engine air demands, when a mismatched turbo compressor V turbine housing pairing creates more air flow at a certain throttle opening than the engine wants to injest. At such air flow levels the I/C is unlikely to be a flow restriction. It is running well and without "causing" surge on several single turbo installations. Sadly, it doesn't look bling, isn't massive, isn't a flamboyant colour, hasn't got a well known logo on it, and fits without compromising other important aspects of the car. for some unknown reason I can sell more than I always expect and order Quote Link to comment Share on other sites More sharing options...
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