what is meant by open? like open as not connected at the cat? well my question is I have my turbo project complete other than the downpipe. Will it effect the turbo if i dont have any exhuast at all? should i put the flange on? im not trying to be cheap. Im gonna get this fixed just temp. I wouldnt really know how to search this out. sorry.let me know asap.thanx guys
yesm open downpipe means you have a downpipe and nothing else behind it. it will not mess anything up, but your torque will suffer making it hard for you to get the car moving. i would reccommend having at least a downpipe connected.
Sorry but this is complete and utter BS. The less restriction in the exhaust of a turbocharged car the better. You will actually suffer more perfomance loss the more you add to your exhaust setup. I would run with an open downpipe (yes, that means nothing at all attached to the downpipe) and see if the volume is exceptable for you. If its too loud, buy a resonator (a $20 cherry bomb does nicely) and some piping and run the exhaust out the back or side. That should quite it down plenty.
Also, If you don’t want your perfomance to suffer drasticly dont go with anything less than 2.5" and dont put a full muffller on. I’ve seen dynos where 30-50hp loss when the complete exhaust is hooked up is not that uncommon.
OMG dude if u have anymeans of tuning… than i would definatly at least go ghetto on a DP hows the ecu gunna read o2 sensor voltage??
U need a o2 sensor and open turbo is just gunna get hot and burn shit in the engine compartment… Id atleast direct it under the car go to menards/homedepot they sell mandrel bent piping for electrcal work better than nothing … than go get ur SS piping
I missed that you have NO DP, lol.
If you KNOW (doubtful) your tune is ok and you dont mind breathing exhaust gas you can safely run without a downpipe. I drove mine to the shop to get the DP made. I would strongly recommend against driving it much further though, the exhaust gasses are pretty bad with NO downpipe.
yeah i took it for a test spin today…boosted about 4 psi. pulls pretty good… im gonna go about 7 psi when i get the pipe done. i tapped into the brake booster i think and the brakes feel super stiff, almost like theres nothing there…any idea’s on that?
sorry, but i meant his performance would suffer if he were to run no downpipe at all. is this not true? i figured he wanted his car to be streetable, and no back pressure at all is bad for streetability, correct? i even said he should run AT LEAST a downpipe. i witnessed a turbo supra running without a downpipe and the driver had noticed a huge drop in low end acceleration. but, if i’m wrong, tell me now so i don’t spread any more “BS” as you say. i’m just going on what i saw. i’d really appreciate it.
Backpressure is NEVER good in ANY car. It’s just a misconception of what is actually causing the drop in low end power. Exhaust piping will actually help suck the exhaust out faster than the engine pushing it out. People just say it’s backpressure because they don’t really know what else to call it. I’d say there’s a very slim to none difference in a turbo car. I ran open downpipe for a long time and noticed no changes when I put the exhaust on it.
Backpressure = BAD all the time
We put chris’s turbo kit on his car here at the house and he was driving it around while Gary and I fabricated the down pipe, and it free spooled alot, and the driver side of his engine bay was charred badly and it melted the plastic covers that cover the timing belt and his coolant over flow bottle.
Recommend some type of directional piping to flow hot gasses away from engine bay. 
Thank you for your polite correcting of my assumptions. Its makes it alot easier for me to learn when you put it like that. So, really, the only reason to run with AT LEAST a downpipe is to direct the hot gases away from the engine bay to keep the underhood temperature down and to keep parts from melting (as Ntegra8d just mentioned)?
Yes I would recommend atleast a downpipe that gets the gases out of the engine bay. I was using just the stock dsm 02 housing as my open downpipe. It only makes a quick 90* bend off the turbo and just dumped into the engine bay. I had extremely high underhood temps and some overheating problems (it was dumping right near my radiator).
any idea why my brakes are barely working after tee’ing off the brake booster?
The vacuum lines are probably leaking. Ziptie all of your vacuum connections, and pressure test the system.
what is the grey thing in the line…i took it out and tee’d it there…im guessing thats why
That’s a check valve. You need that there.
is that why? i’ll try it this weekend
Yea just go to any autoparts store and buy a universal tee… thats what i used before i spent the 40 bucks on a golden eagle vaccum manifold (i highly reccomend this best 40 bones u could spend) it cleaned up engine bay and solved all vac problems… the check valve on most cars is connected to the brake booster and it makes it soo when u are driving and there is no “Vaccum assist” the vac cannot escape the booster with u removing this it has to build up a vaccum in the booster inorder for u to get the “regular power brake feel” soo yea just reconnect it and tee it before this… (before meaning closest to the manifold and have the valve uninterupted on its way to the brake booster)
Hope this helps
i put it back in…worked awesome…thank you so much man. im in your debt
hey no problem glad to help