Speedworks

Hmmm. seems I lost my eye on this threath and missed some post.

Anyway, concrning the internam/external wastegate issue, here's some european design for a local turbo engine

http://www.dsop.net/products/images/dsop_downpipe.jpg

Principle is a "normal" (KKK turbo) exhaust flange with a small divider welded on between exhaust opening and internal wastegate opening. Next are 2 tubes (one exhaust, one wastegate) which is being kept apart for a longer distance.
testing on the actual car it was placed on proved that the longer separation of the exhaust/wastegate tubes improved exhaust flow by not creating flow turbulence right after the exhaust turbine wheel.
Creating a gain of about 11HP on a midranged tuned engine (2liter 16v turbo, standard 204HP, tested at stage 3, 315HP)

However I think this might also provide a solution for the possible use of an external wastegate by cutting of the actual internal wastegate and plasing the external in the extra tube.

Off course the fitment of the extra divider lip on the flange will have to be as tight as possible.


I already postedon the first page telling I had 2 extra turbo's sitting here as weel. i had a closer look at them and they are T3 Garrett turbos with a 42 A/R ratio.
What are my possibilities with these things for a similar customs setup like being discussed here?

Keep up the good work. Really worth following...

SPOautos

Speedworks - Do they sell just that flange? If so do you know the price of it?

Kevin T. Wyum

Started the car. Engine seems fine. Now I have to get a new battery, make my headlights and remember how to program a Motec : )

Kevin T. Wyum

Sonny

The external wastegate has to vent pressure *before* the turbine wheel in order to work properly. Or are you saying that you wanna cut off the internal wg door, separate the housing via a divider, and stick the external on a separate tube?

Sonny

broken93

We'll have to see. I had a long discussion on that very point today with a friend of mine who is an MAE and materials expert and he assured me that the 304 would be fine in this configuration. Again, I can't find out whether or not it's a good idea without having something break, but I do feel that there's enough tolerance in these flanges that I'm not going to have to worry about them shearing any fasteners due to expansion.

HDP

iTrader: (2)

I've got a compressor... a portable Craftsman, 20 gal. 5hp. I haven't used it in about a year, so I hope it still works properly.

broken93

Thx, we can chat about that this weekend.

Godzilla-T78

Take and plumb the front turbo to the rear plumbing and run a larger turbo to the rear.. 8lbs on the t28 and say 15lbs on a t70 easily aquired off of ebay for 400bucks.

broken93

Good god this thread has taken off.

Aside from hammering my server, if anyone wants to see the entire start to almost finished gallery of (118) pics, see

http://www.nopistons.org/gallery/vie...project&page=1

Speedworks

SPO Autos, I don't think they sell the flange separate. and like I said it is used on a KKK K16/26 turbo

I did see this piece in real life when I had the same engine in my preious car. It was a stainless steel flange of about 5 to 6mm thick. I remember the owner saying that the flange was slightly bend and therefore did nog perfectly match the turbo flange.

He said he beter could have done it himself, which I don't doubt, him being an aircraft mechanic for 15 years.

Hello Sonny, yes that's what I meant. keeping both exhaust and wastegate separate by the flange and the welded on divider. But like I said...that divider has to be very accurately cut to match the turbo housing.Which in itself is not that big of a work in opinion.

In this particular case it may also be an option to route the wasteegate tube around because you're getting pretty tight there with both exhaust and turbo narrowing your space to put on an axhaustflange and tubing

Greetz
Neal

broken93

The flanges I ended up getting are the type with the machined-out wastegate pockets that help to direct flow into the outlet without having a split-wastegate flange. I've seen a lot of applications that use this idea, from WRX's to S14's, but I don't think it's that practical or that necessary in my setup. As you can see from the earlier pic I shouldn't have a problem just routing that 2.25" bend around the rear runner. As soon as I have the flange I will get it put together.

Speedworks

You're right.. in your case you got fixed with the machined flange. I just gave it up as an example for an alternative solution. And possibly something to think about if the flange setup would not work out.

As well the better poweroutput thanks to the divided exhaust tubes.

I"ll look up my history to see if I can find the writeup about the test day the owners had with the particular car.

Anyway, like I said, cool project... keep going :-)

broken93

After much discussion and considering yours and other comments, I changed the order to mild steel (and saved $40!).

The other flanges I have are mild, anyway, so I might as well be consistent, aside from risking less breakage.

MrRx

iTrader: (1)

so any updates?...how much has this ended up costing you so far?

broken93

I'm still working on the manifold. I've gotten the front turbo downpipe (2.25") to clear the rear runner just fine. I haven't gotten around to fitting up and welding the rest of it together yet. As soon as I finish the manifold and oil fittings I'll post some photos of the whole assembly on the engine.

Right now my major issue is the wiring harness... It's completely f&@'d. I pulled it completely out last night and started trying to unwrap it (to re-wrap it for the second time), and more connectors crumbled in my hands. Looks like right now I'm going to be saving for a microtech, unless someone else has another suggestion. I'm very open to suggestions right now on the EMS issue.

Money? Let's not talk about money

HDP

iTrader: (2)

Not to topic jack, broken93, but do you plan to attend the annual BBQ next Sunday?

MrRx

iTrader: (1)

Haltech E11, E6X....no but really, how much has this cost you so far?

94RHDFD

iTrader: (3)

If you are wanting a Microtech might I suggest you get it directly from them and not a distributor, the prices are cheaper plus there's a discount for overseas orders. I'm getting mine direct from them for my 20b and saving a ton of money. PM me if you want the exact details.

alberto_mg

I'm a little late to the thread here, but I have a question...

Couldn't you mount the turbos in a more vertical position so that the inlet side is facing the top instead of the front of the car? Wouldn't that resolve the issues with the downpipes interfering with the manifolds?

Cool work.

MrRx

iTrader: (1)

what is the a/r of the t28?

Kevin T. Wyum

Hrmm for some reason my response never made it in RE: mounting turbos vertically. At the time I designed mine I was told the bearings and shaft wouldn't like it, it would act as if it had additional thrust as well as the oiling system and gravity feed of the drain being potentially messy.

Kevin T. Wyum

alberto_mg

I see. Thanks for the enlightenment.

broken93

What Kevin said.