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luvinmycel
01-20-2005, 09:36 PM
What would be required to run an aftermarket wastegate on the stock manifold? Has anyone done this? What kind of aftermarket wastegates have you guys ran?

Thanks.

Snafu
01-21-2005, 02:52 PM
Sorry nobody has answered this.

I'm assuming that whe you say aftermarket wastegate, you mean an external waste gate. That's a pretty darn simple one.

What you'll have to do is one of two things-

A) Weld the little "door" that opens and closes as boost pressure increases,

-or-

B) Run a flange that pretty much seals the door shut, so no air can go through it.

After that, you'll need to modify the manifold some.

I believe that the stock manifold is cast, so it needs to be slowly heated before you or a fabricator cuts/welds a new flange on there. From there on, you need to decide what type of wastegate to run. Of course there are the most common ones, Tial, deltagate, etc. Then you'll need to run a hard line from the wastegate outlet down to your exhaust track.

ChrisD
01-21-2005, 03:45 PM
Hey Tal,

Most people that Ive seen running external wastegates on the stock manifold dont modify the manifold at all. Instead, they run a adaptor plate with a flange/pipe welded to it, and run the WG from there. Most of the time they'd do this they are running something like a t3/t4, etc. :)

Whats your plans?

luvinmycel
01-21-2005, 04:23 PM
Right now, I have a rebuilt stage 1 turbo from turbocharger.com (they say it's good up to 450HP). Next month I start purchasing my JE 9:1 pistons (.020 over), eagle rods, total seal rings, aftermarket intake and exhaust manifold, HKS 264 cams, Haltech E6K EMS, have a valve job done, that's the plans for this year anyway. I may go with a T67 Greddy turbo setup later on, but I can't afford that right now. I already have a dual feed fuel rail (my dad customized the stock one), I have a metal head gasket to go on it and 550cc injectors, it already has a walbro FP, and the fuel pump is wired to run constantly ( no fuel cut ). I think that's about it right now, I may think of more later....LOL

Todd
01-21-2005, 04:30 PM
why the 9:1 pistons?
that will raise your compression...(assuming I'm correct in thinking stock is 8.5:1)

what kind of boost/power are you trying to make?

luvinmycel
01-21-2005, 06:24 PM
Mainly becuase a friend of mine just put 9:1's in his alltrac and said it made a huge difference. I was thinking the stock ratio was 9.5:1, maybe I was thinking of my old 3SFE...LOL

Snafu
01-21-2005, 07:23 PM
Why not run a higher compression? you can make the same figures no lower boost, and also make it a lot easier to drive when you're not in boost.


Stock ratio is 8.5:1 if I remember correctly.

Good luck.

luvinmycel
01-21-2005, 07:49 PM
I'd like to eventually have about 400-500 HP. Hell, just being able to run 14's would be nice.

Snafu
01-21-2005, 07:55 PM
400-500? wow.

You'll need to raise your compression then, otherwise it'll take a LOT of boost.

luvinmycel
01-21-2005, 08:10 PM
Oh yeah, if I buy one of those stainless steel manifolds off of ebay (you know those really pretty ones...lol) how hard would it be to install an external wastegate? Do I need to just have a machine shop do it???

Conrad_Turbo
01-21-2005, 08:23 PM
I'd like to eventually have about 400-500 HP. Hell, just being able to run 14's would be nice.

That makes absolutely no sense... You can get into the 14's with a couple hundred bucks (if that) with mild bolt ons, while getting 400-500hp would take thousands upon thousands of dollars and a lot of skill to do. It's like saying you want a McLaren, but if you can't have if you'll be content with a Chevette.

Conrad_Turbo
01-21-2005, 08:25 PM
400-500? wow.

You'll need to raise your compression then, otherwise it'll take a LOT of boost.

That's the point of a turbo, to make more boost, not gain an advantge with compression ratio. Some turbo drag cars have compression ratios of 7:1, reason being is so they can flow enough air/fuel without detonating.
Powerband is like a see-saw, it's all where you want to put the fat kid.

luvinmycel
01-21-2005, 08:54 PM
Okay, put it this way, eventually I'd like to have 400-500 hp, but considering the cash flow I have right now I'd be content with 14's. That would be a short term accomplishment leading to the long term. You have to take small steps sometimes to get to the big stuff.

Snafu
01-24-2005, 04:27 AM
That's the point of a turbo, to make more boost, not gain an advantge with compression ratio. Some turbo drag cars have compression ratios of 7:1, reason being is so they can flow enough air/fuel without detonating.
Powerband is like a see-saw, it's all where you want to put the fat kid.


Oh, I totally understand that. Don't think I'm totally fucking ignorant.

You're talking about a drag car. He's talking about 400-500 hp in a STREET car. Look at any street 4 cylinder car and tell me that they lowered their compression so they could boost more. Find anybody? Didn't think so.

CelicaGT4
01-24-2005, 04:37 AM
400-500 whp would put you in the high 10's in the 1/4...I think like 225whp would put you in the 14's.

galcrazi
01-24-2005, 12:22 PM
400-500 whp would put you in the high 10's in the 1/4...I think like 225whp would put you in the 14's.

thisis true... if your using forged pistons why even bother with changing the compression. If you build the internasl right you can run 20+ psi ALL DAY. As for 400-500 whp... u are gonna need about $10k.

Conrad_Turbo
01-24-2005, 01:38 PM
Oh, I totally understand that. Don't think I'm totally fucking ignorant.

You're talking about a drag car. He's talking about 400-500 hp in a STREET car. Look at any street 4 cylinder car and tell me that they lowered their compression so they could boost more. Find anybody? Didn't think so.


I can't say I have heard of anyone increasing their compression to get more Hp on a turbo street car. Sure it'd increase the driveability off boost...but having higher comp pistons will allow for less boost and less power. But then how often do you hear of a very daily driveable 400-500hp 4 cylinder engine?

luvinmycel
01-24-2005, 03:56 PM
Back to the initial wastegate subject. Does anyone have pics of an install on a 3SGTE?

Snafu
01-24-2005, 07:17 PM
I can't say I have heard of anyone increasing their compression to get more Hp on a turbo street car. Sure it'd increase the driveability off boost...but having higher comp pistons will allow for less boost and less power. But then how often do you hear of a very daily driveable 400-500hp 4 cylinder engine?

I'm not saying there are many, however if you look on Honda boards, you see everybody running 9.0:1, 9.5:1, hell even 10:1. Maybe I'm not understanding how compression effects power output/heat, so please provide me with some information to prove me wrong. I'm just letting you know what my experiences have been with 4 cylinder turbo cars. High compression makes more power at a boost level. You can turn down the boost can achieve the same power as you would have at the higher boost level with lower
compression.

Luv - I don't think anybody here has installed an external wastegate that I know of, let alone made an install writeup. I know evilspeed put on one his 7afte, you should check that out. It's a few posts down. Hell, just check out homemadeturbo.com they have plenty.

luvinmycel
01-24-2005, 07:36 PM
The main reason I'm asking for pics is becuase of the aftermarket stainless manifolds I was looking at on Ebay. My dad doesn't really see where you would be able to install one on those manifolds and they don't use the stock wastegate.

Conrad_Turbo
01-24-2005, 08:39 PM
The main reason I'm asking for pics is becuase of the aftermarket stainless manifolds I was looking at on Ebay. My dad doesn't really see where you would be able to install one on those manifolds and they don't use the stock wastegate.

They install them in the collector, check out www.full-race.com for manifold pics.

Sean, if raising the compression with boost gives more performance why is it the Mitsu Eclipses' can take 20psi boost much more easily than the 3sgte? Because they have the lower CR, this reduces the chance of detonation, which allows for more boost (IE: mass flow rate of air). A higher mass flow rate of air equates to more power, unless the car is horribly tuned.

Lots of Hondas that have turbo setups go with thicker headgaskets (to drop the CR) or run mild amounts of boost. There isn't too many 400-500hp streetable Hondas that I have heard about...but if there it'd be interesting to see what type of CR they are running to put down that much power.

GT4Chuck
01-24-2005, 08:56 PM
all those stainless ones on ebay do use the stock wastegate mounted on the turbo... i saw one in britain that was constructed to use an external wastgate.


The main reason I'm asking for pics is becuase of the aftermarket stainless manifolds I was looking at on Ebay. My dad doesn't really see where you would be able to install one on those manifolds and they don't use the stock wastegate.

luvinmycel
01-24-2005, 09:02 PM
That link is taking me to some crazy search website.

luvinmycel
01-24-2005, 09:08 PM
My dad's convinced that the stock waste gate is mounted on the exhaust manifold and not on the turbo.

Conrad_Turbo
01-24-2005, 10:02 PM
My dad's convinced that the stock waste gate is mounted on the exhaust manifold and not on the turbo.

The CT26 has an internal wastegate (inside the turbo).

Luni
01-25-2005, 12:16 AM
Yeah its inside the turbo.

Heres the wastegate. Show him this picture


http://i18.ebayimg.com/03/i/03/45/81/3a_1_b.JPG

Snafu
01-25-2005, 03:27 AM
Sean, if raising the compression with boost gives more performance why is it the Mitsu Eclipses' can take 20psi boost much more easily than the 3sgte? Because they have the lower CR, this reduces the chance of detonation, which allows for more boost (IE: mass flow rate of air). A higher mass flow rate of air equates to more power, unless the car is horribly tuned.



Name's Colin by the way. I understand this, and I agree with you. That's the obvious. However, how much power do they make? compare that to a 3sgte. 'Nuf said.

I appologize. I should have restated what I said about having to raise compression for 400-500. I made it seem like you HAD to, however I know you don't, but for a street car like Luv was/is intending to keep his car as, it would be a good idea.