Shane Posted July 10, 2010 Share Posted July 10, 2010 I have just got round to fitting a MBC to mine and bit concerned about that I may not have it right. Its a ball and spring type with a small bleed hole in the main body. I have plumbed it in between the compressor housing and the actuator of the front turbo, as I am pretty sure the diagram that gets posted on here regulary shows. I have not capped the VSV to actuator pipe though, as most seem to think with a MBC its best not to. The ball bearing side of the valve is connected to the compressor housing and the other to the actuator. Think that's right? Ok, I set the controller bolt about 3 maybe 4 turns in from the start of its thread so there was very little pressure on the spring. I have only taken it for short drive so far and quickly hit fuel cut, (loss of power for bit and warning triangle) now according to my Blitz boost gauge this happened just over 1.1bar. So, I stopped and wound the bolt out about 1 turn and stil the same. It's simply too hot in there to adjust it again at the moment but will try once it cools down, I already have 3rd degree burns to my hands from the first attempt! My concern/question is, how course is this adjustment, I mean does it go from say 1.2 to 1.0 bar in say quarter of a turn? or is it as I imagined it would be, a very fine adjustment? Also noticed that I now seem to get what I can only describe as holding back when I go over about 0.8 or 0.9 on the gauge. I guess this could be the plugs or coilpack connectors and I have a set of IK22's to go in but want to get the boost somewhere near under control first. My plan was to run at around 1 bar for a while and then later fit a FCD. Also how come it lets me boost to over 1.1 before I hit fuel cut? Is the 1bar figure an approx. figure that varies between cars? Spec is: Jap spec TT 95 Double decat 3" Japspeed Restrictor ring 1bar Upgraded fuel pump Blitz boost gauge MBC http://cgi.ebay.co.uk/MECHANICAL-BOOST-CONTROLLER-TOYOTA-MR2-SUPRA-TWIN-TURBO-/290452165243?cmd=ViewItem&pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item43a04c527b 3" stainless exhaust, single box Any suggestions gratefully received, thanks. Quote Link to comment Share on other sites More sharing options...
Shane Posted July 10, 2010 Author Share Posted July 10, 2010 Mods. Would you move this to technical please. Thanks. Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted July 10, 2010 Share Posted July 10, 2010 Seriously, get an EBC. Thats the only input I have. Im sure some will echo what Ive said Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted July 11, 2010 Share Posted July 11, 2010 dose a ebc regulate boost for each gear individually? i have a mbc and i get 4psi in first, 5 in 2nd 6 in 3rd 7 in 4th and 9 in 5th ? if i adjust to get 7/8 in the lower gears i go over 10 in 4th and fith and get knocking PITA Quote Link to comment Share on other sites More sharing options...
Shane Posted July 11, 2010 Author Share Posted July 11, 2010 dose a ebc regulate boost for each gear individually? i have a mbc and i get 4psi in first, 5 in 2nd 6 in 3rd 7 in 4th and 9 in 5th ? if i adjust to get 7/8 in the lower gears i go over 10 in 4th and fith and get knocking PITA Sorry Craig mate but that doesn't sound right at all. Obviously it will all depend on the engine loading anyhow. However in my case, I have been up for hours and got it all sussed I think. Firstly, my mannual boost controller adjustment is horrible and very very course/critical. I guess not all are the same but the thread on the adjusting bolt on the one I have is course anyhow so that cant help. But, I have now found a point where in this morning's temperatures I have it sitting just below 1 bar. What I should have done is mount it a bit further away from the engine to make adjustment that bit easier. Ouch! Swampy, yes mate I will be getting a EBC asap now I have played with this one as I can see this one will be a real PITA requiring constant adjustment to allow for ambient temperature change. Regarding my holding back/missfire, it was down to the plugs. There was a set of PK20Rs in there and comparing the gap with the new Densos was like comparing Jordan's love tunnel with Mother Theresa's, although I imagine hers is looking a bit worse for wear now as she has been dead for years:d But sure you get what I mean. The plugs had not been changed for years going by how the grey clips that secure the harness inside the plug cover just fell apart when I touched them. Anyhow, the IK22s cured the holding back at higher boost levels and also now fuel cut comes in bang on 1 bar. Maybe the ECU gets tied up with other stuff trying to work out what's going on when it's missfiring and thats why it was getting over 1 bar before cut came in. Just a guess though. So, all in all it was a good few hours work and pleased with the results. Car feels good and strong and everything seems to be ok. Just had a call from work and looks like I may have to go in so will have a nice 90 odd mile drive each way to really try it if so. Just need to buy a EBC and FCD now. Sorry for the long post. Quote Link to comment Share on other sites More sharing options...
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