Hi everyone

Could you guys tell me what you think about the way i did plumbed the wastgate ?
This is not finished yet

Wastgate merge into a 4" inch exhaust
And im thinking later running under the body 3" exhaust pretty much all way back
If so i will add a cutout echaust just before the 3"

Engine is a ls5.3 , chinease gt45









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I'd prefer the gate to merge at an angle with exhaust flow rather than at a 90*. But it'll work fine the way you have it. Hows the gate teed off of the hot side?

 

Thanks
This is the cheap intake turbo exhaust from ebay for silverado
I build a -spacer -between the turbo and exhaust flange , and from there i have the wasgate coming out of it at approx 45 degree angle.

 

Can you do something like this? #ad


According to the research papers I've read, merging the wastegate flow like you have, can negatively affect the turbine performance.
Basically, the flow out of the turbine hits a wall of exhaust flow from the wastegate. It creates an "aerodynamic restriction" of sorts and causes higher expansion ratio, increases drive pressure which also decreases exhaust flow.

If you can't take it to where I pointed, atleast merge it at or less than 45°. Believe it or not, alot of research and design goes into proper wastegate plumbing on factory systems.

 

When the system is factory every decimal of percentage is important. Of course they computer model the entire plumbing system and perfect on paper then empirically test all derivations within some time frame to find ideal or optimal given the materials science and availability/cost.

When we make our own plumbing systems, it is mostly impossible to perform such careful evaluations.
yes every decimal still counts, but you no longer have any meaningful way to calculate or optimize via testing, and that is where efforts often get lost in the time to optimization. For example one might spend an extra 2 or 3 hours 'correcting' some exhaust union to save 3% (3% of what exactly? does anybody know what they are optimizing anymore?) whereas the system really needed to get rid of those 90 Degree couplers and use the correct size charge pipes and has poorly selected turbine cover and so forth which take far more away (and could have saved time) than the hours spent trying to correct or optimize something far less significant.

In this case yes I believe changing the exhaust gate position to reflect the picture- point it down into the exhaust to maintain the flow vector is a great idea. And given the tack weld I assume feasible. Plausible.

Good idea yes. Easily to do. Keep in mind there are many such puzzles to 'fix' - look at all of your plumbing for easy fixes. Ex. Do not use tight 90* angles. Do not change the size of pipes suddenly. Use the right turbo for the job, did you calculate the flow rate for the turbo at intended power output? All of the optimization is leading up to nothing if the most basic turbo selection technique is wrong for the engine/application. You may gain a few percent here and there only to lose major performance or spool character with wrong turbo selection.

You'll never miss what you never had.

 

Ok after work i did a new piping

I think that should be better ? #ad

 

Much gooder

 

Its better. Dont let the coils get hot though. Blanket the exhaust. Reflect heat from coils. Measure coil with IR gun to make sure it doesn't go much over the temperature of hot oil in the valve cover (185-215*F ~range for external components)

 

Why merge it into the down pipe? I would run it down and dump it beside the oil pan. The other two in here know what they are talking about. I am still trying to figure out my first build.

 

i dont know if i will like the sound of thr wasgate pipe open air
i want be able to ear the tutbo rather the the wastgate pipe

Also i like to listen my engines for noise , clicking ect...

 

My waste gate is dumped. I don't mind the sound. I always through being able to hear it was good thing. It's closed during normal driving.

 

My wg's are dumped. I made mini mufflers for them. You can not hear them at all.

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It's interesting to read that people can hear their WG's when opened and try to quiet them.
I'm surprised that they can even be heard while doing a full boost run and I find this odd that the WG's are louder than the exhaust system.

My car runs three mufflers to keep it quiet and I can't hear when my WG's are opened at all but they are mounted just under/behind the radiator so maybe they're far enough away.

ks

 

Oh that look nice.
Nice jobs
Thanks for sharing

 

I always employ factory style exhaust sometimes extra mufflers and recirculated gates on all vehicles as daily driver toy not racing vehicles.

Low noise is convenient for whats under the hood and surprise. It is more difficult to pull off, like A/C and PCV it speaks more of the owner as a mechanically inclined and engineering. Lose power limited thinking and it becomes obvious. With a turbo you can have 4000hp 10000hp whatever power to spare for PCV, Quietness, Smell-free, Invisible, A/C and big help cleaning oil and maintaining engine with PCV.

I've done 2L 3L 5L 7L they can all sound good and quiet.
Use a cutout for max effort if needed.

 

I dont want take chance to find out i might not like it and redo everything again

 

It depends if you running low or high boost. High boost, not much will come out of the wg.

I ran 3lb wg springs, 4 1/2 currently. IMO it sounded like a city bus, horrible.

I run dual 3" exhaust with only 1 muffler per bank. Pretty quiet. I also have cut outs. I made small mufflers on them also because I like my car quiet. You can hardly hear when they open with them.

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I'm shooting for about 1100-1200RWHP in street tune with the three mufflers and I'm a bit worried of the back pressure so I'm contemplating on installing a pair of large WG's on the merge/third muffler housing to relieve pressure. Still thinkin' tho.

ks

 

I can say at 6lbs and 600rwhp the cutouts were good for 20hp. I forgot to test them at 30lbs. I'm sure it was a substantial gain.

Put a cutout in as close forward as you can. I liked the accuator that you can see in the picture. Works off of boost or vacuum depending what you want. No switch to actuate and instant open/close. And they are cheap on eBay.

 

The more restrictive the exhaust the more a cutout will tend to be worth.

You can measure the difference by comparing boost pressure closed/open.
If the exhaust is restrictive, exhaust gas pressure will force open the gate sooner.
For example with 15psi of boost cutout open but only 12psi with it closed, you can work backwards from gate diameter to find exhaust gas pressure difference assuming the boost control is done open loop.