I am looking into the 16g from a mits and for some reason I have come across many with an internal wastegate which brings up my question...

I have been looking into turbos and learning little by little. I have now come to the point where I am starting to build my kit. I have been searching and can not find any pros cons to an internal wastegate on a tC. Its and auto 2005, I am only looking to boost at about 6 psi and stay within 5-7 at all times, I dont know if this makes a difference on which wastegate to have, I just figured I would mention it. But with the wastegate which is better, are they close, or does it even matter and why so. I am just looking for some info on this subject, if you have experience with an internal wastegate than great, please let me know. Thank you to all that contribute.

 

From what I understand, an internal waste gate is more prone to boost creep and spike. I think this is really only an issue at higher boost levels, though.

I have an internal wastegate with my greddy kit (with a manual boost controller) and it works fine.

 

an internal gate will be just fine for what you are wanting.

some reasons for an external gate is they don't boost creep as bad also you can have them vent to atmosphere which is better for high end HP due to not being as restrictive due to producing less back pressure then a recir or internal set up.

The down sides to open dump is it's loud as all heck

 

Down side?

 

i guess i shouldn't say a down side i just want to hear my turbo and bov @ times. i just get tired of how it sounds at times.

 

pSTURM for your setup internal is fine.

External is for higher boost level and all out better turbo performance and as Syldrin said it can be noisy if you run open dump. External can be rerouted back into the downpipe if you choose.

Internal is more conservative to a point there are setups that hit 400+ but those are STI,WRX,SRT,VW setups and so on.

Auto trans aren't to happy when going pass 9lbs and up so you should be ok at 6lbs with internal wastegate.

 

I tried to upload a PDF file for you to look thru which would give you more insight about forced induction overall but the file is too large. So go to TurbobyGarrett.com and click the turbo tech section and read up. Some of the formulas won't make sense so don't try to figure it out.

 

awesome info, thanks all, and thank you gunnist14 for the link, I will check it out! I have another q...what size inj should I run with that setup? I see people using 720cc 550cc 440cc etc. I dont know which ones to purchase. I was thinking the 440cc since I will be running low boost levels. But it would be nice to have a concrete answer from some of you guys that know for sure

 

At 6lbs on a 16g, 440cc should be enough. I think I maxed out my 440ccs on my 18g at around 8-9psi.

 

since you are planning to stay low boost go internal wastegate and 440cc should be fine. but you plan to go higher in the future go external wastegate and 550cc. the injectors will be a bit overkill just make sure you consider that when tuning. wont hurt the car or waste more fuel.

 

If your going the 440 injectors route, I have a set for sale. Pm me if your interested