EvoPowerMods o2 dump vs QTP o2 dump
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From: Joisey Shore
EvoPowerMods o2 dump vs QTP o2 dump
Did some searching and saw QTP at the track close to end of last summer. I have had a EPM o2 dump since the first week they went on the market (thank you to Q for the great service
) anywho.....who hear is running the EPM o2 dump or the QTP o2 dump?
has anybody seen or heard of the QTP o2 dump having a power jump on the EPM o2 dump?
if you do a search look at the EPM o2 dump pipe for the wastegate and then look at the QTP wastgate dump pipe. Clearly the QTP o2 dump hs a wider mouth opening for the wastegate gases.
so if anyone has saw or heard of differnt power gains please post, vendors are welcome to chime in with pros and cons.
just curious i heard the EPM made power over the QTP dump at a tune day from another evo owner but im not 100% sure.
post away
please keep it friendly haha
has anybody seen or heard of the QTP o2 dump having a power jump on the EPM o2 dump?
if you do a search look at the EPM o2 dump pipe for the wastegate and then look at the QTP wastgate dump pipe. Clearly the QTP o2 dump hs a wider mouth opening for the wastegate gases.
so if anyone has saw or heard of differnt power gains please post, vendors are welcome to chime in with pros and cons.
just curious i heard the EPM made power over the QTP dump at a tune day from another evo owner but im not 100% sure.
post away

please keep it friendly haha
Yeah lets get some real juicy details if any into this post. numbers numbers if anything, I have qtp and my friend has epm but we have identical tunes and feel and pull the same neck and neck.
if you have something to say, please do. but dont post something like epm FTW! or qtp FTW!
It's useless
if you have something to say, please do. but dont post something like epm FTW! or qtp FTW!
It's useless
i was told the fitment for the qtp was bad compared to the epm one...
i want to know if theres a gain in hp/tq between an aftermarket o2 housing and an o2 dump...
is it worth the extra $150 over a regular o2 housing?
i want to know if theres a gain in hp/tq between an aftermarket o2 housing and an o2 dump...
is it worth the extra $150 over a regular o2 housing?
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EPM has stated that their research and testing showed that it was the turbine side design that made power on their part. QTP stated the opposite ... they feel that the WG side is where power can be made.
Based on my understanding of how a turbo and wastegate work, I'd side with EPM. In the most basic sense, increased flow through the turbine helps the turbo spin easier and increased flow through the WG helps control spikes and creep. Restricted WG flow can reduce turbine efficiency, but if you've ever looked at the WG opening on the stock turbo you'd quickly see that it's a restriction in itself.
Based on that theory, EPM should make more power as the turbine outlet has a tuned radius for better flow.
And, before anyone calls me out on it, I did help with R&D on the EPM part, so my opinion may be slightly biased.
Based on my understanding of how a turbo and wastegate work, I'd side with EPM. In the most basic sense, increased flow through the turbine helps the turbo spin easier and increased flow through the WG helps control spikes and creep. Restricted WG flow can reduce turbine efficiency, but if you've ever looked at the WG opening on the stock turbo you'd quickly see that it's a restriction in itself.
Based on that theory, EPM should make more power as the turbine outlet has a tuned radius for better flow.
And, before anyone calls me out on it, I did help with R&D on the EPM part, so my opinion may be slightly biased.
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From: Joisey Shore
alot of the responses are good. i went with EPM since i heard they make awsome power...with lil boost creep. The tunnel on the EPm is tuned also i belive. i was jsut curious if on the QTP dump made more power because of the wider mouth opening for the wastegate gases.
does anyone no if the wider opening for wastegate gases will increase power or will it just induce boost creep.
does anyone no if the wider opening for wastegate gases will increase power or will it just induce boost creep.
alot of the responses are good. i went with EPM since i heard they make awsome power...with lil boost creep. The tunnel on the EPm is tuned also i belive. i was jsut curious if on the QTP dump made more power because of the wider mouth opening for the wastegate gases.
does anyone no if the wider opening for wastegate gases will increase power or will it just induce boost creep.
does anyone no if the wider opening for wastegate gases will increase power or will it just induce boost creep.
I have the EPM dump and have seen boost creep in my testing. I tested it against a ported Megan housing and they both crept to about 19.5 psi @ 5500 RPM. Given the difference in design, this leads me to believe that the wastegate itself is the cause of the creep, not the housings.


