Quicker Spool Up with External Wg

[set3422]

I don't have an external wg. Can anyone please verify if this is true on quicker spool up with external wg?

The reason I'm asking this because I'm running a td06-20g 7cm with internal wg. Seems like boosts takes forever to build (around 4k rpm). With no cats and full 3" exhaust, I think the exhaust is flowing too well with no back pressure.

Without any back pressure, the internal wg probably is opening up when it's not supposed to. I think this is what causing my full boost lag. Any help is appreciated.

Thanks for the space.

 

[L2RTSiAWD]

Techically yes. Because an external will open at the absolute last second where a internal does have to open a little early in order to regulate boost pressure safely.

 

[nano]

A buddy of mine got one with he's big 16G on a 7cm turbing housing, and full 3" turbo back with no cat. IT really didn't make any difference. It reaches full boost by 3400rpm. It used to reach full boost by 3100 to 3200 before he's manifold got ported to 7cm gasket.
IF you're having real bad spool up problems, make a boost leak tester and check for boost leaks. They'll be there when you least expect them.

 

[KenTSIII]

My old 20g setup used to get full boost (20psi) right around 3400 rpm. The external will work exactly like the internal if it's hooked up only using the side port. It'll open up progressively as boost increases.. hurting spool. But the external can't be blown open early, where as the internals have a big problem w/ this happening. The only way an external will open up at the "last second" is w/ the use of an electronic boost controller. I went from a Hallman style MBC to the HKS EVC EZ & noticed a 150-200 rpm quicker spool.

 

[set3422]

Would like to thank everyone for their input. Have something that might you some money. I bought 92-99 big rotors for $30 each from Autozone. Out.

 

[Slowboy]

I don't have an external wg. Can anyone please verify if this is true on quicker spool up with external wg?

Can you send a pic of what your WG actuator looks like? If you have the basic 20g actuator from a cycone upgrade, it has a very weak spring. It will not hold boost for anything.

If you have an actuator that is adjustable, you can shorten the rod and boost response will be almost as good as an external gate.

Regards,

Mike Huml

 

[set3422]

MikeH,
Heard about your Slowboy Team. Those are some sweet custom turbos you go there. I'm at work now, but will send you a pic tonight. thanks.


Set,

 

[Slowboy]

Sounds good, I look forward to it!

Regards,

Mike Huml

 

[set3422]

here's the pix. see what you think. Thanks.

set,

Originally posted by Slowboy
Sounds good, I look forward to it!

Regards,

Mike Huml

 

[rubbersidedown]

Originally posted by nano
A buddy of mine got one with he's big 16G on a 7cm turbing housing, and full 3" turbo back with no cat. IT really didn't make any difference. It reaches full boost by 3400rpm. It used to reach full boost by 3100 to 3200 before he's manifold got ported to 7cm gasket.
IF you're having real bad spool up problems, make a boost leak tester and check for boost leaks. They'll be there when you least expect them.

So are you saying that the porting of his manifold had a direct negative affect on the turbo spool time? If so, why would this be? I'm really curious, i'm not trying to be a dick.

 

[Slowboy]

That looks like a 14b/ 16g actuator. They are usually not strong enough to hold that flapper shut, especially if it is a bigger than stock flapper!

Regards,

Mike Huml

 

[L2RTSiAWD]

Ya on my L2R it has a bigger garret actuator with and adjsutable actuator I wasn't spooling as quickly and once I cranked on that actuator a few times I noticed immediate improvement.

 

[set3422]

MikeH & John,
Ya i rigged that 14b actuator to fit with the 20g. Shimmed the actuator bracket by putting extra nuts behind it. I think this is what John said about adjusting the garrett wg actuator in order to give a little more tight shut on the gate.

By the way, the gate I'm using is off Chevy 350ci 1.7" exhaust valve. I grinded down the valve to about 38mm and ported the wg hole to about 36mm. Don't know if this will contribute any lag.

 

[set3422]

how about this? you think this would help.

set,

Originally posted by set3422
MikeH & John,
Ya i rigged that 14b actuator to fit with the 20g. Shimmed the actuator bracket by putting extra nuts behind it. I think this is what John said about adjusting the garrett wg actuator in order to give a little more tight shut on the gate.

By the way, the gate I'm using is off Chevy 350ci 1.7" exhaust valve. I grinded down the valve to about 38mm and ported the wg hole to about 36mm. Don't know if this will contribute any lag.

 

[L2RTSiAWD]

Actually with mine you don't shim it. The is a lock nut you break loose then there is another nut the you turn clockwise to increase pre-load or counter-clockwise to decrease preload.

 

[Slowboy]

The fact that you have a bigger flapper means there is more "air" pushing against a larger surface area ( bigger flapper ), making it harder for that actuator to hold the door shut. That is why boost response is so slow!

Regards,

Mike Huml

 

[larryd]

remember with an external gate its all about the spring thats inside the gate.. John was saying something about the external will not open up until the last possible minute.. well thats not true in my case.. I have a 0.7bar spring in my wastegate which is 10lbs and Im running 20lbs of boost so my wastegate is actually opening at 10lbs..

 

[set3422]

MikeH,
I kind of know what you're talking about having a bigger flapper will require more pressure to hold it shut. So you're think that 38mm flapper is definitely too big for the 10lb stock actuator to hold the gate shut. That makes sense because the bigger flapper has larger cross section, hence more exhaust gas accumuolates at that concentrated area. More exh gas = more mass which equals more force. Force can be derived in terms of pressure by dividing the area of the flapper. So you think running a 15 or more psi wg actuator would help spool up or at least holding the gate shut. Where can I get a 15 psi actuator besides from HRC. Thanks again.

Set,

 

[larryd]

Set.. this the same Set from earlier today at the meet?

 

[set3422]

That's why RRE is selling Tial springs at different rate.

Originally posted by larryd
remember with an external gate its all about the spring thats inside the gate.. John was saying something about the external will not open up until the last possible minute.. well thats not true in my case.. I have a 0.7bar spring in my wastegate which is 10lbs and Im running 20lbs of boost so my wastegate is actually opening at 10lbs..

 

[set3422]

yo what's up Larry? How is your car boosting?

Set,

Originally posted by larryd
Set.. this the same Set from earlier today at the meet?

 

[larryd]

eh, its ok.. still blowing off IC pipes.. BTW make sure you check out the meets forum Set.. we got pics up in there from today.

 

[set3422]

you could get some t-bolt clamps from Napa for $2.

Originally posted by larryd
eh, its ok.. still blowing off IC pipes.. BTW make sure you check out the meets forum Set.. we got pics up in there from today.

 

[larryd]

yeah, well im lookin into replacing the entire intercooler setup so im waiting to see what i do first.

 

[Slowboy]

I kind of know what you're talking about having a bigger flapper will require more pressure to hold it shut. So you're think that 38mm flapper is definitely too big for the 10lb stock actuator to hold the gate shut. That makes sense because the bigger flapper has larger cross section, hence more exhaust gas accumuolates at that concentrated area. More exh gas = more mass which equals more force. Force can be derived in terms of pressure by dividing the area of the flapper. So you think running a 15 or more psi wg actuator would help spool up or at least holding the gate shut. Where can I get a 15 psi actuator besides from HRC. Thanks again.

Set,

You are right on with your explanation!

Yes, running a 15 psi wg actuator will absolutely help boost response. No doubt about it!

I also can get you an actuator for your tdo6 20g, but you would have to tap the compressor cover. I can get a 15- 25 psi one, or a 19 - 35 psi one for this turbo. Both are from Holsett.

Picture is what it looks like.

Regards,

Mike Huml