serious question need answer to!!!
 

alright its been about 8months since i completed my exhaust with 3inch straight pipe...in other words i have a 3in catless dp with straight 3in piping to a can....no resonators or cats...my question is...am i losing a lot of back pressure without a resonator at least on this tiny turbo???

ive been thinking about adding a resonator but trying to get some answers first

Less backpressure =more power on this car. No reason to add any back pressure

As far as the engine goes, it gets enough backpressure from the turbo so you're not going to burn up any valves.

The only problem with running castless is that you have to worry about turbo seals leaking oil and then smoking. Usually switching to a heavier weight oil helps but if you don't see smoke, then don't worry.

Oh and resonators don't add backpressure really, just cut out drone and make the exhaust sound quieter

sweet 3" exhaust to a can...have you checked your fuel pressure? stock pump may have trouble with the extra flow

yeah the fuel pressure is still good...fuel pump hasnt gave out yet....but it seems in the high end seems like it dies out

The reason why im wondering about the back pressusre is ever since ive added a full 3in exhaust i feel like i lost power after that.........Ive raced people that i used to beat befor i got the exhaust and after 4th they just pull ahead.....

Post up some logs and we can see if there is any reason for the power loss.

That's what I've thought about when I went full 3in. I had two resonators on each tip. Started to smoke so I was going to go back go stock and put my stock cat back on (didn't have time for the dp) and for some reason it stopped smokin.

yea idc about the smoke happens once and while nothing crazy more on the lost of high end but im also thinking its cuz the base tune its on so once i get a protuned should help

You need to properly tune for a catless DP.


Tapadatass

Play some loud hard metal music in the car. You might be driving "by ear". The car is louder now, you might be acting a little conservative on the gas.

so what are you using to log/monitor this.. because after reading the thread it appears you have no tuning solution as of right now.. you cant just change the way this car breathes without adjusting the tune..

its tuned on stage 2 on the ap ots getting protuned soon and i data log with that and dashhawk

thats what im thinking appericate it

get it tuned.. That should probably help, the resonator would not necessarily add back pressure with the tiny turbo we have (as stated previously)

I think once you get it tuned you would be ALOT better.

I still wanna know what your fp numbers are, aka, let's see an AP log.

Also, you need to google "is backpressure good". I still can't believe there are fuckheads telling people they need backpressure on their cars.

everytime i try to upload the logs its looks crazy not organized at all any good programs for that

I'll bet its laying down at higher rpm and load due to fuel pressure dropping. He needs to log high pressure fuel pump psi versus rpm in fourth gear at WOT and post up the numbers.

As all have said, backpressure is absolutely a non issue on a turbocharged car. The more free flowing exhaust the better. It is not like a normally aspirated engine application. Turbocharged engines produce maximum power with absolutely no exhaust behind the biggest catless downpipe that can be connected to the turbo --- if, and only if, the engine is tuned properly and the fuel pump is keeping up with the increased air and fuel demand.

From what i read so far it really seems like your Fp is letting you down towards the higher ends of the gear... before you pay for a protune just check your logs and make sure thats not the prob.... if you get new fp after protune you may need to retune anyway