External Wastegate?

[sleepersupra]

i was discussing turbos with my buddy and he asked is having an external wastegate better than an internal?.....:dunno:

i know that this will vary but in my sig thats my upgrades and i was looking at a sp bolton turbo and this question came up...

thanks,
mike

 

[hottscennessey]

an external is no better than an internal.. the only benefit is allowing the WG and turbine to be seperated (with a dump tube).. possibly allowing more flow.. but that all depends on your exhaust setup and turbo as well. however, if you have an external and no dump, exhaust gases could be sucked into your turbo causing you to lose horsepower. Internals do a great job, after all... IJ runs one .

 

[dbsupra90]

i think the external is a lot better.

first, there is less turbulence in the dp from the gate dumping into the stream. this is considering if you go open dump. if you do reroute the dump back into the exhaust, you can do it further down which would still help w/ the turbulence.

second, external gates are much larger than internal ones. this allows more flow, control boost, and lack of boost creep. of course this will need to be matched to your turbo. no need for a 60mm hks gt gate for a 57mm turbo. conversely, you wouldnt want a 38mm gate on a gt42. assuming it is matched correctly, the benefits apply.

downside. cost and fabrication to some degree depending on if you go open dump or reroute. noise- if you go open dump it can be a downside as well if that would be a problem.

do you need an external gate? it really depends on the setup. but its hard to make a blanket statement of internal is all you need. given the choice, id always go external.

 

[IJ.]

On a big loose AR Turbine housing the internal gate is a no brainer as it doesn't need to work very hard to control shaft speed!

On tighter street style turbo's the external will win hands down if you choose a quality unit.

 

[sleepersupra]

On a big loose AR Turbine housing the internal gate is a no brainer as it doesn't need to work very hard to control shaft speed!

On tighter street style turbo's the external will win hands down if you choose a quality unit.

ok well i was looking at these...

http://www.horsepowerfreaks.com/pri...erformance/Turbos/Turbo_Kits/part/MK3_Bolt-on

and then these....

http://www.horsepowerfreaks.com/pri...urbo_Kits/part/MK3_External_Wastegate_bolt-on

which is gonna be better? my goals are around 400 hp, whether it be to the wheels or not and i think that should get me there.

 

[IJ.]

SS: Which ones in particular?
(You linked pages with 9 options each)

 

[sleepersupra]

SS: Which ones in particular?
(You linked pages with 9 options each)

the first one on both links

 

[IJ.]

The ext gate kit has a better upgrade path if you change your mind later on but both seem a little exe for what you're getting!

The 4>6 week wait time would put me off as most of this sort of kit should be in stock and at most 1>2 weeks wait.

 

[sleepersupra]

The ext gate kit has a better upgrade path if you change your mind later on but both seem a little exe for what you're getting!

The 4>6 week wait time would put me off as most of this sort of kit should be in stock and at most 1>2 weeks wait.

what do you suggest going w/

 

[IJ.]

I'd shop around a bit and see what the other vendors have and what the wait times are like!

400 isn't a big stretch but it's not as easy as everyone likes to make out either!

You need to look at the total package and how you're going to achieve it or it's going to end in tears.

 

[yaitsme]

I just got my 7M back together with the externally gated kit you're looking at.

I'm plenty satisfied with my choices & would go external again if given the choice. Everyone has to make their own decisions, mine were based as much on my sailing mentality: compartmentalize ... that is: if it breaks, can you fix it without tearing everything apart to get there.

IJ has already made the most important points with his street turbo vs track turbo analogy & the suggestion to 'think full package'.

Check out my build thread (a little more manageable than IJ's :biglaugh: ) here, for an idea of what I think that turbo kit needs to breathe easily.