wat boost do mps 3 run stock and wats the most u can get outta them before upgrading turbo
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wat boost do mps 3 run stock and wats the most u can get outta them before upgrading turbo
14-14.5 psi stock
cant push them much past 18psi
I agree with Sam I run mine at 18 psi but it did spike to 22psi :hand: and set of the boost alarm when Rino was driving :norty::coolsmiley: .:marg::marg::marg:
The Colster :coolsmiley:
Agree with above but just to add boost is limited in the lower gears in both the 3 and 6
so what do you guys think is the upper most limit is when tuned without putting excessive stress etc. So Col, you reckon 18psi is safe as a daily driver or are you happy to strain the turbo and get a new one ???
Do what I have done and get a switch installed so you can flick between PSI's I chose 14.5PSI and 18PSI so 99% of the time I'm running the lower figure I was going to run 16psi to 18psi decided on the economy way :) ......... Food for thought
Stock turbo over 18psi isn't doing anything, just blowing hot air. Effective up to 18psi I reckon. Any higher and you would want a bigger turbo.
Stock is 13.6 - 14. I've seen 14.5 in some stock. Some stock BOVs are reported as bypassing at 15 as a "protective" measure but I don't necessarily hold with this, as on boost, top and bottom BOV lines are at a common pressure anyway, so it's not actually bypassing, unless it can leak to atmosphere, and I'm not aware of them doing or being able to do this. Most tuners will set a max of 17.5 on stock turbo, as I have. As stated above, 18 or more is generating more heat than useful work, to say nothing of running potential overstress and reducing enduring reliability if the engine hasn't had some attention. Better to stick with 17.5 and do other things to help the engine utilize that, like improve the breathing (e.g inlet and dump). Boost ain't everything.
Yes I think it's OK because as a daily drive aound town & in traffic the boost gauge stays under boost or at the most 5psi , my car would only run 18 psi boost about 5% of the time , but Rino's dual boost settings switch is a good idea as well , but for me if i'm giving it the full wellie I want the maxamin boost . If I blow the turbo so be it but I wouldn,t go to a bigger turbo I would get Allstar tuning to pull the internals out of the original & re build it with high quality vanes & ball bearing shafts & what other magic they do , in my opinion a bigger turbo means much more lag coming in at higher rpm. I am no mechanic or tuner I will take Dougs advise ( above ) & get the boost lowered to 17.5 at the next tune .Quote:
Originally Posted by kookie
The Colster :coolsmiley:
you can get scary good numbers out of a gen 2 with only 15psi of boost :)
I used to think boost was everything as well, you will get more benefits in increasing flow and decreasing IAT than straight boost increase with these smaller turbos.
i got mine set to 19PSI, but it wont pass more than 17 in the lower gears, im guessing not enough air, or maybe summer heat? but on highways in 4th,5th ive noticed it hitting 21-22PSI!
The first 3 gears are torque/boost limited.Quote:
Originally Posted by rayd
The stock turbo is only making heat after 17psi.
18psi dyno runs show more heat/less power produced with back to back runs.
RAYD, be wary of boost spikes (say, +18psi) at lower rpm on freeway in higher gears. If you have a Dashhawk you can see the engine loadings.
Yep, I noticed that I was getting fuel cut in 5th 6th when in lower RPM, dialed down to 17.5PSI until I get my DP and tuneQuote:
Originally Posted by Doug_MPS6
Boost isn't everythig with these cars. Lean it out, add a smidgen of boost and more aggressive timing.
I'm attempting this now using my haltech interceptor, hopefully it works out well!Quote:
Originally Posted by Jmac
I installed a boost gauge on my stock MPS 6 to find that in city driving it easily reaches 15 - 16psi, and on the highways goes up to 17psi. I gotta say that i am disappointed as i was hoping that stock MPS would produce less psi than that, and that i would get good gains by increasing boost, and doing some other mods.
What to do now?
DO NOT LEAN THESE CARS OUT!
Engines with forced induction NEED to run rich. More fuel+less timing+more boost= Safe power. The guys in the states are leaning out their cars and blowing the engines.
Will an after market Boost controller get rid off the low boost control in the lower gears?