boost issues

[sambo]

Hi guys and gals,

Ok so now Im running a few mods..... put on a richmod ecu last week, and.....omg!!! It was fast (Courtesy of Macaroni, cheers mate!) Then last night I fitted a MBC. It first boosted like mad and nearly tore my arms off! I didnt push it too hard because I didnt want to blow anything, plus the MBC screw was turned to full boost. Then after 10mins of driving, it decided to not boost as much anymore. It went back to how it was before any mods were put on (boosting only halfway). I had a look at it in the daylight today, and couldnt see anything wrong, I turned the MBC right down, and hey presto! Its boosting well over 14 again! Although this is mostly down to the ecu I think, the MBC is not giving me much more. So Im thinking of turning it halfway, or something like that.

Could someone tell me why it couldnt cope with having the MBC at full boost? Im thinking the engine is probably running weak, but....just not sure.... And should I try turning it up more?? Muchos thanks guys

p.s when it was running well last night I beat a golf VR6

[sambo]

Ok, now I have the MBC turned about halfway, and its giving me good boost low down yet not taking away the high rpm boost from when the richmod ECU kicks in.

When the MBC is turned up fully.... is it supposed to take away boost from the higher rpm?? I am not sure Anyone know?????

[esta]

i'm afraid i cant help with turbo knowledge... but...

p.s when it was running well last night I beat a golf VR6

WELL DONE MATE!!!!!

[sambo]

haha why thank you esta! And to be honest.... I think its something about living in Leicester.... because when I was trial and erroring the MBC settings yesterday, some stupid guy in a new celica tried it...... I got annoyed with his immaturity, so.... I beat him on the straights and on the roundabouts!

I want to try it on a quarter mile stretch sometime. We timed it 0-60 (on the speedo) and it came out with 6.5 seconds. Going pretty quick now!

[esta]

I want to try it on a quarter mile stretch sometime. We timed it 0-60 (on the speedo) and it came out with 6.5 seconds. Going pretty quick now!

Wow! Thats pretty damn amazing!!

[macaroni]

Sorry to butt in here, but I think you've answered the question yourself. Turn the MBC down to where it likes it best.

If you remove the wastegate pipe there will be no boost limit at all and the ecu won't even know anything about it.

If you get a good 14psi boost, leave it at that and go get them Celicas!

[rpruen]

Hi guys and gals,

Could someone tell me why it couldnt cope with having the MBC at full boost? Im thinking the engine is probably running weak, but....just not sure.... And should I try turning it up more?? Muchos thanks guys

The reason the MBC doesn't give that much more is that the modified ECU gives about as much power as possible with a little safety margin.

The reason the boost drops is the ECU takes action to prevent you melting your engine. You would have done that fairly quickly if I hadn't left the safety features in the ECU.

The reason the modified ECU doesn't increase the boost so much at lower RPM is that with a hot engine, the oil pressure is too low, and bearing damage could result.

The whole idea of the ECU mod is to have something that you can plug in to a standard car, and will get the best performace, without damage.

If you are going to use an MBC with it, then keep the boost to something sane. Also with more boost at lower RPM you should be using thicker oil, say 10W50 fully synth or better, otherwise engine damage will result in the end (It may take a while, but it will happen).

It's your car, so you can do what you like, but bear in mind that the modified ECU has limits for a reason. That reason is to give long engine life.

Richard

[sambo]

Ok thanks for your help, really appreciated. I was planning for an oil change in a few days anyway so will do what you say about the 10w50 fully syn. I have set the mbc pretty low and that keeps the ecu giving happily moderate boost. I dont think theres much more with the mbc in there now.

But....first thing is first. I need a new clutch because the other day the engine decided to rev up rather than give the richmod kick! Well, I'll check any adjustment first, then clutch replacement.....

Again loads of thanks for your help

[rpruen]

But....first thing is first. I need a new clutch because the other day the engine decided to rev up rather than give the richmod kick! Well, I'll check any adjustment first, then clutch replacement.....

Again loads of thanks for your help

No problem, I'll try to help if possible.

The modified ECUs tend to show up clutch problems, due to the almost double torque in mid RPM range.

If doing the clutch, take the flywheel off and have it machined, as if it isn't completly flat the new clutch will not hold. Places here seem to charge about 15-20 quid to grind the flywheel, money well spent IMHO. It will also show up any cracks or defects that are present, exploding flywheels are not funny.

Richard

[sambo]

Ok cool thanks, I'll be having a look into that then. I have to wait until my exams are over first

.......Macaroni, fancy doing my reflection seismology exam?! Starting to get annoyed with all this revision

[urosr]

I want to try it on a quarter mile stretch sometime. We timed it 0-60 (on the speedo) and it came out with 6.5 seconds. Going pretty quick now!

Wow! Thats pretty damn amazing!!

which gear at 60mph,