**NEAT PART...LOOK EXT WG BOTTOM MOUNT**

[jgauspohl]

This would work instead of using the POS internal gate setup...now is there anyway to get this or should I make my own or buy a screamer pipe one and modify it with a vband flange for a Tial 44?

[okevolution]

I would do this as it would reduce backpressure and increase spoolup. I would buy an aftermarket o2 housing that separates the flow from the WG and exhaust and have a pipe welded in on the WG side and run a Tial 38mm WG. Just weld the internal flapper shut. Trust me, it will be extremely loud

[95lstegman]

I would do this as it would reduce backpressure and increase spoolup. I would buy an aftermarket o2 housing that separates the flow from the WG and exhaust and have a pipe welded in on the WG side and run a Tial 38mm WG. Just weld the internal flapper shut. Trust me, it will be extremely loud

looks like in order to use that, you'd need to leave the flapper open. otherwise the wastegate would be downstream of the turbo and wouldn't really do anything. or maybe i'm looking at it the wrong way, but i don't think so.

interesting . . . i would be VERY interested to see how spool is affected. this would significantly (although not vastly) increase the effective volume between the cylinders and the turbine housing, which would definitely decrease transient response, but i want to see if the gain in response by having the external gate cancels it out for a positive gain. it's especially questionable since the flow to the external WG would still have to flow through the turbine housing and the stock WG flapper/hole.

i think i will still stick with my idea for stock manifold w/ ext. WG all extrude honed for my final solution to the spool problem on my car. and maybe replace the flange with a T3 flange. low volume, ext WG, and surprisingly good flow w/ the extrude honing (and some grinding beforehand).

[okevolution]

You can get the same results either way, use an aftermarket WG or just run a tube off the WG side of the o2 housing.

[jgauspohl]

I've tried emailing grenade to see how their results are with this setup...like the guy above said...I was wondering if it would affect spool due to the external gate being on the exit of the turbo housing...but if you look forced performance sells turbos with external vband wg flanges on the housing of the turbo...in essence this wouldn't be much different except the fact you're leaving a internal gate flapper (out/open) out of the equation and you're lengthening the flow slightly to 38mm wg, 44mm, ie...setup a few inches down. I figured this would be really great too because you could mount an in cabin MBC if needed rather close..say maybe your shifter console or near your right leg..and have little length on the vacuum. I'm going to do this if I can just find a screamer pipe for cheap.

[Td5turbo]

WTF? So all your doing is replacing the stock wastegate with another one....but its still internally gated (in the since of exhaust flow), thus making no significant gain other than looking cool. You could get the same result by using an HKS or HKS style dump/outlet/elbow/o2housing (whatever you want to call it). Or just running a seperate pipe (like the HKS dump) and just having it dump under the car. If you want a true ext. gated bottom mount, give Full-Race a call...they are making one bottom mount that you can specify if you want a ext. flange (i think only a Tial, but not sure) welded on for an addition like $100 or so.

[BaliLover]

Not quite, the internal gate is a problem because it has a difficult time holding at higher boost levels and many people see boost drop in the upper RPMs. Yes this would be replacing an internal gate, but with a stonger unit better suited to holding higher boost levels. I'm assuming you'd take the wastegate actuator off of the internal gate so it could just move with the exhaust flow and the external WG would hold the boost instead.

I don't know how affective this would be in real life, but in theory it should work.

[twofourzeroSX]

yea but if u need to boost up that high wouldnt it mean ur probably going beyond the efficiency of the turbo anyway? i mean whats the point of boosting a t25 up to 18psi? the internal wastegate works fine for 12-15

my answer... get a better turbo that doesnt even have an internal wastegate....

[ralphsdiorama]

Do I see a flashlight haha

[driftin_sr20det]

I got a gt28rs and it already sounds like I have a 300 lb rattlesnake under the hood. Its loud as hell, I love it. But I think this is a pretty cool idea, I would try it if I didn't think it wouldn't fit very well on a LHD.

[jgauspohl]

WTF? So all your doing is replacing the stock wastegate with another one....but its still internally gated (in the since of exhaust flow), thus making no significant gain other than looking cool. You could get the same result by using an HKS or HKS style dump/outlet/elbow/o2housing (whatever you want to call it). Or just running a seperate pipe (like the HKS dump) and just having it dump under the car. If you want a true ext. gated bottom mount, give Full-Race a call...they are making one bottom mount that you can specify if you want a ext. flange (i think only a Tial, but not sure) welded on for an addition like $100 or so.

The reason why this would be better #1 ease of use for all the internally gated t2 flanged turbos. #2 as the guy below you stated...internal actuators are not as efficient and strong as let's say a tial 44mm. Also why would anyone use the t25...seriously now don't state the obvious. #3 this would make it possible for people on a budget to get the same performance...not necessarily as good as a full-race...again obvious but better than an internal gate setup. Plus you could use practically any bolt on exhaust part on the market for it....I don't know if clearance with the steering column would be an issue. I'm either going to do this kind of setup with a ported stock manifold and have it heat treated and coated or get a HKS 3037s and do what everyone else does put a flange on the stock manifold. I'm looking mainly for the performance...I've built my motor not for bragging rights but for performance...and well to beat the hell out of at DG trials, SEDA, DDay, Drift Fury events.

[jgauspohl]

bump. would like some other people's input on this....besides thinking I'm against the grain by not going top mount and saying it won't work...that argument is already solved....IT IS basically just a better performing internal gate setup.

[95lstegman]

td5-you need to understand that it's not a matter of internal gates being weaker than external gates. the problem is that the act of bringing the wastegate flow back into the same stream as the main exhaust flow creates pressure in the pipe leading from the wastegate. this pressure makes the wastegate have a harder time staying closed. hence, at high RPM the boost falls off. try dumping the wastegate flow from an internal gate to atmosphere and you won't have even a hint of this problem.

by the same token, i'm sure that no turbine dump on the market is designed as well as it could be. i'd like to take a GReddy and make a neat little addition inside it to make the turbine flow scavenge the wastegate flow. in other words, rather than create pressure in the space between the flapper and the spot where the two flows meet, it would create a vacuum. hopefully it wouldn't induce too much turbulence, but that's where SolidWorks fluid dynamics package comes into play, hehe.

i'm thinking of dumping the WG flow in such a way with an HKS style turbine outlet, and possibly cutting the flapper off to keep turbulence to a minimum. i may even lap the hole like a performance valve seat to help as well. in fact, now that i think of it, i might do this as well to the turbine housing.