Turbo/Efficiency Discussion

[sergechronos]

The turbine housing itself is supposed to flow MUCH better than the TD05's as well.

Serge, I 100% agree with the way the wastegates are merged back into the manifold being a crap design.

There is a lot of debate going on in regards to spool time with the 68hta. But I hit full boost currently at about 4200, and they are coming on hard by 3800. Most of the dsm guys are reporting little to no lag difference with the 68hta. Granted that's on a 2.0-2.4.

The way my 16gs behave at higher boost suggests theres something going on with the exhaust velocity IMO.

I think you're both looking at a similar thing here though: The existing WG design is garbage for the most common manifolds in use (3SX old ones and IPS.) I haven't had a chance to get my hands on a set of DR, DNP (although 3SX original manifolds were based off of DNP TD05 manifolds) or the new 3SX (I may try to take a trip over there this week to get a look at them if they have any on hand, but they use open dumps so not a great comparison.) WGs dumping AT turbine wheels and at bad angles is a recipe for poor flow, basically leading to the turbine wheel having to fight itself to flow. Probably as much of a reason for performance gains with open dumps on this platform as the effective exhaust diameter gain from doing it.

I'd say a large part of the real benefit of the FP turbos is the improved turbine housings coming in at 8cm vs the 7cm of the E3 housings, it's a fairly substantial improvement for high RPM/high PR situations. That said, I thought (and could be wrong) that the 68HTA offered an improved compressor housing as well?

[futurevr4man]

That said, I thought (and could be wrong) that the 68HTA offered an improved compressor housing as well?

They offer one, yes. The normal one is a machined out 16g housing. I haven't heard any real benefits from the upgraded housing and I did a lot of research on it. When I called them, they said I will only see an improvement in the really high PR stuff... 35psi+

[NOMIEZVR4]

Its Tuesday..dyno numbers coming today?

[familyMAN]

WG design? Who cares...run all of the boost! Just kidding.

[sergechronos]

WG design? Who cares...run all of the boost! Just kidding.

Trust a 4G guy to say something absurd like that

Sent from my SCH-I545 using Tapatalk

[Streamln1]

It was rainy here all day so not a good dyno day. Prob going next week

[Streamln1]

I think you're both looking at a similar thing here though: The existing WG design is garbage for the most common manifolds in use (3SX old ones and IPS.) I haven't had a chance to get my hands on a set of DR, DNP (although 3SX original manifolds were based off of DNP TD05 manifolds) or the new 3SX (I may try to take a trip over there this week to get a look at them if they have any on hand, but they use open dumps so not a great comparison.) WGs dumping AT turbine wheels and at bad angles is a recipe for poor flow, basically leading to the turbine wheel having to fight itself to flow. Probably as much of a reason for performance gains with open dumps on this platform as the effective exhaust diameter gain from doing it.

I'd say a large part of the real benefit of the FP turbos is the improved turbine housings coming in at 8cm vs the 7cm of the E3 housings, it's a fairly substantial improvement for high RPM/high PR situations. That said, I thought (and could be wrong) that the 68HTA offered an improved compressor housing as well?

Thats really a good question..i think the upgraded cover is prob a td06 sized one..so it wouldnt fit with my current config. I have always wondered if that tiny 1.25" outlet on the td05 was creating a bottleneck.

I like the UPP headers other than some of the runner angles on the rear header look a little too sharp. I think i can prob take some cues off my ips headers and improve from there.

[sergechronos]

When I called them, they said I will only see an improvement in the really high PR stuff... 35psi+

i think the upgraded cover is prob a td06 sized one..so it wouldnt fit with my current config. I have always wondered if that tiny 1.25" outlet on the td05 was creating a bottleneck.

Given the kind of airflow each turbo can create, and turbulence being generated at .4 mach, I'd have to think that airflow coming out of the compressor outlet would be fairly turbulent. A larger outlet should reduce restriction and have smoother airflow, netting some kind of gains I would imagine, but FI engines don't really tend to give a crap so maybe not. Intake system is under pressure and the flow is continuous, so likely a large part of the reason why changes on the intake side don't net us the kind of gains that they do on the exhaust side (where the gases come out in pulses and velocity tends to matter far more.) Throw in that smaller sized piping and outlets pressurize quicker, any changes that increase the diameter of the piping means that the turbos have to work that much harder to fill the additional volume at the same kind of pressure (likely why FP says that it's only under a very high PR that you start to see a difference.)

Still somewhat baffling to me though that most intake and throttle body upgrades attempted to these cars haven't produced much for gains when they seem to make a very large difference for 4G guys. Only thing I can imagine is that our valve area is so much more of a restriction than the intake piping compared to a 4G car, in such a case no change the compressor housings would make a noticeable difference to performance on the 6G engine.

[donniekak]

Given the kind of airflow each turbo can create, and turbulence being generated at .4 mach, I'd have to think that airflow coming out of the compressor outlet would be fairly turbulent. A larger outlet should reduce restriction and have smoother airflow, netting some kind of gains I would imagine, but FI engines don't really tend to give a crap so maybe not. Intake system is under pressure and the flow is continuous, so likely a large part of the reason why changes on the intake side don't net us the kind of gains that they do on the exhaust side (where the gases come out in pulses and velocity tends to matter far more.) Throw in that smaller sized piping and outlets pressurize quicker, any changes that increase the diameter of the piping means that the turbos have to work that much harder to fill the additional volume at the same kind of pressure (likely why FP says that it's only under a very high PR that you start to see a difference.)

Still somewhat baffling to me though that most intake and throttle body upgrades attempted to these cars haven't produced much for gains when they seem to make a very large difference for 4G guys. Only thing I can imagine is that our valve area is so much more of a restriction than the intake piping compared to a 4G car, in such a case no change the compressor housings would make a noticeable difference to performance on the 6G engine.

If anyone with a 6g ran a real intake manifold like the 4g guys, then they'd see better gains from throttle bodies.

[Streamln1]

Yeah, our surge tanks are small, I would say slightly shorter runners and a larger surge tank would help, but the shape of the hood vs engine really doesn't leave much room for changing, I have seen a couple pretty badass ones for the 6G but with the given price tag of said intakes, well not going to be a good seller.

I am not really wild about the N/A hybrid manifolds that are out there. I think we could do better.

4G guys have HOW many intake manifold options again? like a dozen? LOL.