Robzki Posted May 17, 2011 Share Posted May 17, 2011 Hi I'm in no way a mad driver, I only ever get on the second turbo when I'm really trying. probably only see 0.3bar with general driving. Hence I very rarely test the system to see what it will make. I have very slowly (over the last 3 years) gone bpu, and have never been truly impressed with the difference the changes have made. but haven't really tested it. From what everyone tells me bpu should be noticeable. There has probably been 2 times that I have gone to overtake etc and have been blown away by the performance. At all other times its just 'fairly quick' which makes me think I have an intermittent fault. At the moment the spec is: 1st and 2nd decat 3" Catback but with a sard hiflow race cat (no restrictor ring) Walbro Srd fmic iridium (cooler) plugs Stock airbox with k&n No Bov new coilpack clips/ serviced frequently etc fpd removal On sunday I had a trip down to the ind est to see what the turbos were making. only because it was dead quiet and perfectly straight 1/2mile on nice tarmac(a rarity round here) I have fitted some new PLX gauges which plot the last 10-15 seconds so I can see how the boost was made on each run. I'm sure that these are accurate as not only do they match up with the boost controller but they also matched the old hks mech' gauge at known places. Out of 3 good runs I made 0.76, 0.78, 0.75. Maximum from a standing start to redline in 1st and 2nd (auto). On the plot there was a complete loss of boost at what appeared to be the gearchange, is this normal? (it could have been at the transition though) The second turbo did seem to come in at 4000rpm a mild 'push' but it may have just felt like that. Like I say it was nothing 'special' I have searched but tend to get lost in technicalities. I wouldn't mind someone pointing me in the right direction. what to check first etc. I can't find any leaks on the ic side of things. The only thing that it could be is the sard cat. but surely I should get more than 0.78? I may be expecting too much? On dry tarmac with my foot planted to redline in first and second it didn't break traction once, normal? Sorry for the long explanation, any questions please ask. I would like to sort this as I'm kinda losing the 'love' Thanks Rob Quote Link to comment Share on other sites More sharing options...
scotty71 Posted May 17, 2011 Share Posted May 17, 2011 (edited) if you are making .76 bar at BPU with no restrictor ring in place I would have thought there will be some underlying issue somewhere as stock boost for TT J Specs is around .76 So youre full bpu with no RR in place and still boosting at stock levels... Have you the means to try replacing the sard racing cat to see if it makes any difference. What boost controller are you running and what settings is it on? My spec is nearly the same as yours and Im hitting 1.0 bar (have RR and no boost controller) with decats I get a big push at 4k and boost gauge flicks from .4ish to 1.0bar still gives me the willies so how these really big power guys get on I dont know Just another thought you could be driving like a pussy roll at 60 and plant the kickdown you should feel good boost Edited May 17, 2011 by scotty71 (see edit history) Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 17, 2011 Author Share Posted May 17, 2011 LOL, I usually drive like a pussy, but sometimes I make the effort to act like a hooligan It is a greddy profec 'a' I have the boost controller off at the moment as it isn't programmed. I'm assuming it can't lower the base boost so I leave it off to keep it out of the equation. I have been thinking about a new catback but have other things to throw money at at the moment. I would have a hissy fit if I blew another few hundred squid to make no change. The sard cat is welded inline so would be tricky to remove. When you say it gives you the 'willies' Thats what I'm missing, its just 'ok' even when the second tubby comes online I'm never sure whether it has or whether its just the boost coming back in from the 1st after the transition dip, if you know what I mean. Quote Link to comment Share on other sites More sharing options...
scotty71 Posted May 17, 2011 Share Posted May 17, 2011 well it keeps my attention at 4k> when turbo 2 comes online when gas pedal is planted. I get a small pause from T1 - T2 but the boost hits very well after 4k Maybe it gives me the willies as Im still on j spec stoppers Yeah BC just increases boost, is it all rigged in and powered up? Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 17, 2011 Author Share Posted May 17, 2011 Yep, it gives me the same reading as the plx stuff. It works on 'fuzzy logic' though so needs some full power runs to get it to learn the boost curve. There is a filter in one of the lines that seems a little 'blocked' I'm going to remove it to see if this is an issue(doubtful i think) Quote Link to comment Share on other sites More sharing options...
Guest Budz86 Posted May 17, 2011 Share Posted May 17, 2011 If your boost controller is off you should only see stock boost levels, which is around 0.76 bar as Scotty has said. Try getting that programed and you should see an increase. Not sure if not having the restrictor ring is a good idea as it could let the tubbies overboost, but from the sounds of it as long as you are sensible with the boost controller you should be ok Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 17, 2011 Author Share Posted May 17, 2011 I get what you're saying but with double decat, and a catback, surely I should get a little more than 0.76? even with the hiflo cat. It just feels dull. It has however been outstanding on a couple of occasions. which leads me to there being an issue. Also it would be irrelevant whether I had a RR in place if I upped the boost with a controller. The RR is there to keep a sensible base boost. I could be wrong as the sequential system wouldn't be my specialist subject on mastermind Quote Link to comment Share on other sites More sharing options...
scotty71 Posted May 17, 2011 Share Posted May 17, 2011 (edited) yeah budz got a bit confused there, with no rr in place you should be boosting over 1bar and using the BC to get upto 1.2 but every car is different but as said you have not got a RR and you are not over boosting. What catback exhaust you running? my ring keeps me at .95-1.0bar so I either keep it at that or add me a BC Edited May 17, 2011 by scotty71 (see edit history) Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 17, 2011 Author Share Posted May 17, 2011 (edited) Not sure on the make of catback, it doesn't look at all restrictive, could be wrong. This is the cat, it is v small and I still can't see that this is the problem http://www.mkivsupra.net/vbb/attachment.php?attachmentid=109038&d=1272544264 I do remember hitting 0.9 bar in the distant past. just found a post saying the same my memory ain't what it used to be This exhaust: http://www.mkivsupra.net/vbb/showthread.php?168892-help-identifying-an-exhaust&highlight=sard+cat Edited May 18, 2011 by Robzki (see edit history) Quote Link to comment Share on other sites More sharing options...
redtwinturbo Posted May 18, 2011 Share Posted May 18, 2011 I do remember hitting 0.9 bar in the distant past. Seeing 0.9 bar in the past could have been down to colder weather or a higher gear than 1st or 2nd (more load). My money would be on the exhaust and or sports cat being naturally restrictive. Quote Link to comment Share on other sites More sharing options...
mellonman Posted May 18, 2011 Share Posted May 18, 2011 okay please check here for symptoms http://www.mkivsupra.net/vbb/showthread.php?35926-The-sequential-system i would also say exhaust maybe there are a couple of things to check plumb the vac hosese back to stock bypassing the boost controller as they can cause problems see here as i had a similar problem http://www.mkivsupra.net/vbb/showthread.php?236884-inlet-temps-vs-boost-issues every car is different but there are some posible things for you to look at Quote Link to comment Share on other sites More sharing options...
CanisLupus Posted May 18, 2011 Share Posted May 18, 2011 Could be the Cat you have. Do you probably know the CPSI? Quote Link to comment Share on other sites More sharing options...
boomstick Posted May 18, 2011 Share Posted May 18, 2011 It works on 'fuzzy logic' though so needs some full power runs to get it to learn the boost curve. I have a Blitz BC and 'fuzzy' does NOT work because we have sequential twins, maybe the Greddy BC has the same problem? Can you get it out of the 'fuzzy' setting and manually input 1.2bar? Stop driving like a and learn how the car behaves at WOT with different BC settings and weather conditions. Quote Link to comment Share on other sites More sharing options...
Guest Budz86 Posted May 18, 2011 Share Posted May 18, 2011 Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 18, 2011 Author Share Posted May 18, 2011 (edited) Lets stretch our imagination and assume I know how to drive.... It has boosted more at warmer temps. I'll look into the flow on the cat. But it does feel sluggish. surely a double decat with 3" catback even with the sard cat in place should see more than 0.75bar Isn't stock 0.8? I just have a feeling that it isn't right. Would looking into trying ttc give me any clues? I will take the greddy boost controller out of the system. It supposedly can programme itself to run on a sequential system. Its a case of doing a full throttle run in a higher gear and letting off the throttle for a moment at the transition. I don't really have an interest in upping the boost with a controller at the moment as it will just put more pressure on the tubbies and mask any issues if there is a problem elsewhere I do appreciate any help. I'm getting the impression that the general concensus is that 'its fine' Edited May 18, 2011 by Robzki (see edit history) Quote Link to comment Share on other sites More sharing options...
mellonman Posted May 19, 2011 Share Posted May 19, 2011 plumb it all back to stock and see what you get, then you can fault find better as most of the problem solving is from stock format, just do one thing at a time, then test plumb back to stock = you will know if its the boost controler plumb ttc = you will know if its the egbv sticking and if vsv's are working also if it has a vac pipe problem being that if the egbv closes when engine is off then there is a leak in the system all of this takes 15 min to do just might need some vac pipe Quote Link to comment Share on other sites More sharing options...
boomstick Posted May 19, 2011 Share Posted May 19, 2011 (edited) Lets stretch our imagination and assume I know how to drive.... I'm getting the impression that the general concensus is that 'its fine' I am glad you took note of the smeylis Its always a PITA to locate the source of this kind of problem. The 0.75bar is def. not fine! With a 3" decat (with SARD cat) you should see 1 to 1.1bar. It sounds like the seq. system is OK... I would loose the greddy BC, check all hoses (pressurise the IC system) for leaks, and you could test the VSV's. I had similar problems and gave up after a year of testing, replacing and spending a huge amount of money on problem(s) with the seq. system. I had all seq. hoses/valves/springs/butterfly's removed: TTC. More lag, more power (due to removal of restrictive butterfly), less problems... Going single in a few years... Good luck mate! Dennis Edited May 19, 2011 by boomstick (see edit history) Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 19, 2011 Author Share Posted May 19, 2011 Thanks both of you, Seems very sensible, I've checked all over the system for cracks, splits or disconnections. I'll remove the bc at the weekend and see what that does. If I see no improvement I'll have a look into ttc. Not that I truly understand the ttc but I'll have a read up. It is bordering on the edge of 'fine' but you know your car and just get a feeling when something isn't right. Its probably a downside of slowly fitting bits over a long period without really testing them one at a time. I'll try and get a small vid of the plot showing the boost curve. Did you get yours sorted in the end Dennis? Thanks again I'll let you know how I get on Rob Quote Link to comment Share on other sites More sharing options...
boomstick Posted May 19, 2011 Share Posted May 19, 2011 Did you get yours sorted in the end Dennis? I did the TTC as a last resort... If the seq system works its a great system! TTC, you will have more lag, but I got rid of everything concerning the seq. system. With the removal of the "big/thick" butterfly in the exhaust track I def have more/faster power. I have the BC set for 1.3bar (steel blades) and the Supra pulls like Keep us posted! Quote Link to comment Share on other sites More sharing options...
BazzaAlpine Posted May 19, 2011 Share Posted May 19, 2011 Definately interested in how you get on as I think I have something similar with mine. Only got the 1st decat and a 1bar rr (no boost controller) but I still only get .7 bar boost. Changed a whole load of the hoses and even put a SSQV BOV on. No difference. Does yours idle okay? Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 19, 2011 Author Share Posted May 19, 2011 I'm a little worried about ttc long term as there seems to be a lot of discussion about fuelling. My wideband sensor has just turned up so I'll get that fitted at the weekend. yeah my idle is fine. have you tried removing the RR? saying that the first decat is the most restrictive so you 'should' see more than 0.7. I'd remove the ssqv and send it to me I did have a similar problem in the past which turned out to be a faulty stock bov. I am now running with no bov until one turns up for sale on here. I'll let you know what I find. Rob Quote Link to comment Share on other sites More sharing options...
Guest Carsten Posted May 19, 2011 Share Posted May 19, 2011 Runnin in TTC since 6 month If the ECU registered that you run TTC it will regulate the fueling Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 19, 2011 Author Share Posted May 19, 2011 I thought that the stock ecu was very limited in what it would 'learn' all it could really work with was the knock sensors and advancement of the ignition timing before the turbo comes in. I figured it couldn't really adjust the fuelling much beyond stock using narrowband sensors. I know people that swear by it and others that flame people for trying. I'm open to learning Quote Link to comment Share on other sites More sharing options...
Guest Carsten Posted May 19, 2011 Share Posted May 19, 2011 Read and talked to a lot of guys. I can´t tell you the exact technical background, cause technical wise my experience is very limited. But it is said, that for a perfect powerband in ttc you need an other ECU/Piggyback etc. But just if you really want everythin top notch. Which includes bigger Fuel Pump (non Jspec) etc. Running TTC with stock setup is fine. Not optimized, but fine. I posted a comparison (ttc/seq) dyno somewhere on the forums. Result were that you get a little more top end power with ttc. Quote Link to comment Share on other sites More sharing options...
mellonman Posted May 19, 2011 Share Posted May 19, 2011 run ttc just to check the workings of the squential system thats all unless you like it Quote Link to comment Share on other sites More sharing options...
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