[Rob@RBTurbo]

Here is a reference of the latest development of Standard RB Turbos combined with TFT inlets, allowing unrestricted RB Turbo Performance on our customer car documented here:
http://www.e90post.com/forums/showthread.php?t=1081011

Datapoints-

RB Car (Blue lines)
E92 XI/AWD Automatic Transmission in 4th gear. Independent results.
RB Standard Turbos with TFT inlets, Billet 15T Compressor, MHI 12 blade clipped turbine, stock charge pipe
Boost- Unknown (slightly below 50% WGDC)
Fueling/Tuning- OEM HPFP with inline LPFP. E60. Fueling insufficient at this time and to be addressed at a later date. Wedge/BQ Tuning.

Competitve Car (Red lines)
E90 RWD Manual Transmission in 4th gear. Shop results.
Competitive 2+ Turbos with no inlets, Billet 20T Compressor, Proprietary 9 blade Garrett turbine with a 15* clip, stock charge pipe
Boost- ~29-25psi (slightly below 70% WGDC)
Fueling- Competitive Double Barrel with SteveAZ LPFP solution. 100% E85. Fueling sufficient to max out turbos. PTF Tuning.

As you can see the RB car having a very evident disadvantage with drivetrain losses, manages to absolutely destroy the Competitive 2+ car at low RPM's and even hang right with them on the top end. The RB car seems to have much nicer results overall considering the drivetrain losses (not even considering the 20% extra WGDC potential in the RB's yet unleashed!!!).

Without going too much into the hardware decisions made in each setup, it is fair to say that one is demonstrating a MUCH better curve and response than the other… while maintaining a similar top end at less effort. So sharing this comparison graph seemed appropriate.

Thanks,
Rob

PS. Sorry if the overlay is not of the best quality. We had to have it quickly photoshopped.

PSS. Some may take note of the Competitive record graph NOT being the advertised 645rwhp record. We will gladly redo the overlay if anyone can prove that the 645rwhp RECORD has a verifiable MPH dyno to prove it was in 4th gear (and not 5th); as we could not source that evidence NOR was the competition supportive in providing it.

[pr0gress]

Very interesting data. I'm guessing this stems from what was happening on ****** earlier.

Still great numbers for us XI AT guys who are often neglected! Thanks for sharing rob

[Tiago@VRSF]

I'd take that blue line all day (RB's) in this comparison but I'd love to see this same test done with the same tuner/same mods. At least the same inlets/fmic/tuner.

Would be even better if it was on the same car but that's quite a bit to ask considering how much time is involved in swapping these turbos out.

[Rob@RBTurbo]

Originally Posted by pr0gress

Very interesting data. I'm guessing this stems from what was happening on ****** earlier.

Still great numbers for us XI AT guys who are often neglected! Thanks for sharing rob

You are welcome.

Originally Posted by Tiago@VRSF

I'd take that blue line all day (RB's) in this comparison but I'd love to see this same test done with the same tuner/same mods. At least the same inlets/fmic/tuner.

It is always great to have exact apples to apples comparisons, although not possible. So usually it simply comes down to a "run what you brung" mentality. Either way this RB car has so many data points making it the underdog, that any other potential argument a moot point. Keep in mind it was a 3rd party comparison to a shop car as well, the shop car certainly is not going for records with supplemental parts that are inferior. Thanks for the compliment though, as we agree the blue line is a total devastation to the red one.

Originally Posted by Tiago@VRSF

Would be even better if it was on the same car but that's quite a bit to ask considering how much time is involved in swapping these turbos out.

For this reason we feel the best way to get real results is where it counts, the dragstrip. Our products have always dominated that scene, and will likely continue to do so. But for those who appreciate dynos here is a great comparison, in which the RB car is a large underdog yet entirely dominates.

[Myrder]

Why was this deleted earlier? I think having charts like this comparing all kits out there ST and hybrid would be extremely helpful for the consumer.

[Rob@RBTurbo]

Originally Posted by Myrder

Why was this deleted earlier? I think having charts like this comparing all kits out there ST and hybrid would be extremely helpful for the consumer.

We accidentally violated policy by naming a vendor, and it was apparently quickly reported. It has been now corrected as said vendor was not named.

Thanks,
Rob

[ksalih]

Good data Rob, and I'll comment the same in the previous thread that got deleted: while this isn't a very controlled comparison (difficult to do so), this is great data. I agree with the data points that put the RB car as the underdog, however I am unsure of the effect a screen over the turbo inlet has on airflow restriction. I want to assume no turbo inlet with a screen has similar flow air flow restriction (low) as the TFT inlets do. Maybe somebody else can chime in on this. Assuming the restriction is similar in both configurations, kudos to the RB car with the underdog data points.

[Myrder]

Originally Posted by Rob@RBTurbo

We accidentally violated policy by naming a vendor, and it was apparently quickly reported. It has been now corrected as said vendor was not named.

Thanks,
Rob

Thanks Rob, I find it funny there is a tune sticky naming vendors, est HP TQ and cost yet a dyno chart is out of line.

[Rob@RBTurbo]

Originally Posted by ksalih

Good data Rob, and I'll comment the same in the previous thread that got deleted: while this isn't a very controlled comparison (difficult to do so), this is great data. I agree with the data points that put the RB car as the underdog, however I am unsure of the effect a screen over the turbo inlet has on airflow restriction. I want to assume no turbo inlet with a screen has similar flow air flow restriction (low) as the TFT inlets do. Maybe somebody else can chime in on this. Assuming the restriction is similar in both configurations, kudos to the RB car with the underdog data points.

Thanks for your post, its appreciated and brings up some points worth discussing.

We think the screens provide as close to zero restriction that is possible, the next best thing being no screens. Certainly less restriction than ~4ft of plumbing and actual air filters would provide.

However screens could arguably allow "hotter" pre turbo airflow inlet temps. In the words of our competitor, they believe the IATs could of cost them 5whp. In our opinion, we are ok with that statement as it could (in worse case situations) be found to be very close to that.

Ultimately it all is much less concern than powering a transfer case with two additional wheels combined with an Auto Trans (vs. Manual Trans), on E60 (vs. 100% E85), and much less WGDC to boot (ie. turbo efficiency).

Thanks,
Rob

[ksalih]

Originally Posted by Rob@RBTurbo

Thanks for your post, its appreciated and brings up some points worth discussing.

We think the screens provide as close to zero restriction that is possible, the next best thing being no screens. Certainly less restriction than ~4ft of plumbing and actual air filters would provide.

However screens could arguably allow "hotter" pre turbo airflow inlet temps. In the words of our competitor, they believe the IATs could of cost them 5whp. In our opinion, we are ok with that statement as it could (in worse case situations) be found to be very close to that.

Ultimately it all is much less concern than powering a transfer case with two additional wheels combined with an Auto Trans (vs. Manual Trans), on E60 (vs. 100% E85), and much less WGDC to boot (ie. turbo efficiency).

Thanks,
Rob

I agree and didn't mean to discount this point whatsoever. Hope this thread doesn't turn into a vendor war and stays within topic. Good to see threads like this.

[C.Pop]

Depends on what he used for a screen. Actual screen material is extremely restrictive, as in -a HUGE restriction. If he used something like chicken wire, obviously it's not nearly as restrictive, but both are far more restrictive than a proper air filter; that's why air filters are pleated/etc. I realize it may be initially counter intuitive, but this same discussion has occured on many different platforms and all come to the same realization. Adding in the inlet tubing will be a restriction, but not pulling air right off the manifold will help. We'll see. I hope for the sake of big numbers that the screens he used were actually restrictive, but who knows, it's all conjecture at best.

[Rob@RBTurbo]

Originally Posted by C.Pop

Depends on what he used for a screen. Actual screen material is extremely restrictive, as in -a HUGE restriction. If he used something like chicken wire, obviously it's not nearly as restrictive, but both are far more restrictive than a proper air filter; that's why air filters are pleated/etc. I realize it may be initially counter intuitive, but this same discussion has occured on many different platforms and all come to the same realization. Adding in the inlet tubing will be a restriction, but not pulling air right off the manifold will help. We'll see. I hope for the sake of big numbers that the screens he used were actually restrictive, but who knows, it's all conjecture at best.

C.Pop,

Said competitor is using high quality turbo screens (they have posted them, and they are just that); designed for optimum flow and providing some compressor protection against debris. It is beyond extremely safe to say they are not holding back the potential of the turbo, at least to not any point worth discussing.

Inlet temps could be of concern, sure, but this was discussed above.

Thanks,
Rob

[ksalih]

Originally Posted by C.Pop

Depends on what he used for a screen. Actual screen material is extremely restrictive, as in -a HUGE restriction. If he used something like chicken wire, obviously it's not nearly as restrictive, but both are far more restrictive than a proper air filter; that's why air filters are pleated/etc. I realize it may be initially counter intuitive, but this same discussion has occured on many different platforms and all come to the same realization. Adding in the inlet tubing will be a restriction, but not pulling air right off the manifold will help. We'll see. I hope for the sake of big numbers that the screens he used were actually restrictive, but who knows, it's all conjecture at best.

We can assume all day long, and while I agree, I personally discount assumptions about what he used and what he ran etc., and prefer facts if I want to make conclusions. If the screen was restrictive, for sake of argument, we just won't call the RB car the underdog due to the negative data points (e60, WGDC, etc.) and we'll call them equal. This data is still better than any other assumptions made by both vendors. Good stuff. Your car spools fast Chris, but the lack of rock chips on your front bumper give me the impression that you aren't driving fast enough

[jippii ensio]

The comparison shows the importance of matching the compressor and turbine wheels. Having oversized compressor wheel causes lag while the top end is limited by the turbine wheel. 20t is too big compressor wheel for this application as you can see from the graph.

[Rob@RBTurbo]

Originally Posted by jippii ensio

The comparison shows the importance of matching the compressor and turbine wheels. Having oversized compressor wheel causes lag while the top end is limited by the turbine wheel. 20t is too big compressor wheel for this application as you can see from the graph.

This is a good point. A TD04L sized turbine is approaching a poor match for a 19T compressor, let alone a 20T sized compressor (especially in a TD03 compressor housing). Excessive clipping can help with the mismatch but then you ultimately end up with poor transient response.

In the case of this competitive turbo it is shown to have a very undesirable combination of parts placed together, especially in that we are seeing around 180ft/lb increase of torque at 3250rpm with only a 40ft/lb hit at 6750rpm (discarding drivetrain loss disadvantages).

The WGDC of the RB car at redline suggests that the boost was on a big taper as well, so we are more than confident that if the WGDC was pushed further that gap would be closed and likely topped very easily topped. We could not push it any further with the limited fuel supply, so we will just have to deal with what we have for now.

It will be interesting to see how things progress as more samples are shared, but this data is very compelling to say the least.

Rob

[shadow191]

On a previous car, I used window screen material. Literally bought it from Home Depot and clamped it to the turbo. I needed a filter with a 4" inlet and there was a 6 week back order. Then when I got the filter, I was curious as to if there was an impact between the screen and the filter. Long story short, we found a 1-2 whp variance between no screen, screen, and filter. And it was a random variance so just noise.

But this was at lower boost pressures 12 psi on a larger turbo so not quite analogous to this situation. Also, it was a top mount turbo so we weren't pulling air directly next to the manifolds. Still, I don't think that screens are really a restriction.

Originally Posted by C.Pop

Depends on what he used for a screen. Actual screen material is extremely restrictive, as in -a HUGE restriction. If he used something like chicken wire, obviously it's not nearly as restrictive, but both are far more restrictive than a proper air filter; that's why air filters are pleated/etc. I realize it may be initially counter intuitive, but this same discussion has occured on many different platforms and all come to the same realization. Adding in the inlet tubing will be a restriction, but not pulling air right off the manifold will help. We'll see. I hope for the sake of big numbers that the screens he used were actually restrictive, but who knows, it's all conjecture at best.

[dx1541]

Rob its just amazing after all these years there was so much hidden power in your turbos, the response curve is just amazing, 600whp all day with no loss in response is something very much respectable! Why did I even sell my car!!!!

[WedgePerformance]

Originally Posted by dx1541

Rob its just amazing after all these years there was so much hidden power in your turbos, the response curve is just amazing, 600whp all day with no loss in response is something very much respectable! Why did I even sell my car!!!!

After seeing the pics of your car Dx, I have no clue why you sold it. It was beautiful to say the least. You must really respect and honor your brother in-law. He's a lucky man. Find a 335xi and build a GTR killer.

[Verify]

Amazing! I read elsewhere that people were trying to refute the DT losses associated with the XI.

They said if a RWD AT is known to have 15-18% DT loss, they tried saying an XI AT would be about the same.

I can not see in any realm that 2x the amount of moving parts, literally exactly 2x the setup would not be significantly more. Lets say the rwd at is at a low end with 15% DT loss exactly. Well, if you double the components, would it not be acceptable to assume 2x the losses? It sure would, but we know 2x is not right.

However, if you assume 1/2 the losses, rounded DOWN, its another 7%. So it is TOTALLY reasonable to expect that an AWD system is operating at 22% DT loss.

The results themselves are astounding, but when you see clearly the RB car was at a significant disadvantage in every aspect (except turbo hardware) it still produced much better results, from a turbo vs turbo perspective. Its clear to see which Turbo is properly designed. Test the same turbos on a similar vehicle with similar DT losses, and I would wager the RB car outperforms competition in every aspect by an even larger amount, roughly 7% better

[Rob@RBTurbo]

Originally Posted by Verify

Amazing! I read elsewhere that people were trying to refute the DT losses associated with the XI.

They said if a RWD AT is known to have 15-18% DT loss, they tried saying an XI AT would be about the same.

I can not see in any realm that 2x the amount of moving parts, literally exactly 2x the setup would not be significantly more. Lets say the rwd at is at a low end with 15% DT loss exactly. Well, if you double the components, would it not be acceptable to assume 2x the losses? It sure would, but we know 2x is not right.

However, if you assume 1/2 the losses, rounded DOWN, its another 7%. So it is TOTALLY reasonable to expect that an AWD system is operating at 22% DT loss.

The results themselves are astounding, but when you see clearly the RB car was at a significant disadvantage in every aspect (except turbo hardware) it still produced much better results, from a turbo vs turbo perspective. Its clear to see which Turbo is properly designed. Test the same turbos on a similar vehicle with similar DT losses, and I would wager the RB car outperforms competition in every aspect by an even larger amount, roughly 7% better

This is very well stated. It would seem obvious if one takes a step back and looks at the data entirely, but for some reason many are reluctant to accept the facts in lieu of the "+" symbol having to mean something more. Great marketing we presume.

Thanks much for your contribution.

Rob

[Blaster400]

Originally Posted by Rob@RBTurbo

This is very well stated. It would seem obvious if one takes a step back and looks at the data entirely, but for some reason many are reluctant to accept the facts in lieu of the "+" symbol having to mean something more. Great marketing we presume. Rob

Rob - it must be very satisfying to know that after all the drama these past couple years, it turns out you have had the best performing stock frame turbos all along. Congrats on these latest numbers they are remarkable.

I have had my RB's for over two years and I just ordered the TFT intake kit. Looking forward to hitting the drag strip this spring!

[Rob@RBTurbo]

Originally Posted by Blaster400

Rob - it must be very satisfying to know that after all the drama these past couple years, it turns out you have had the best performing stock frame turbos all along. Congrats on these latest numbers they are remarkable.

I have had my RB's for over two years and I just ordered the TFT intake kit. Looking forward to hitting the drag strip this spring!

You are correct that we have been antagonized and belittled for years now by our competition, for lack of "change" or "advancements", while they dance around trying to find something better batch change after batch change.

In short it is extremely satisfying to see the TFT inlets finally allow the RB's to perform to full capability. RB Batch 1 seems to be not all that bad after all

Thanks,
Rob