Nice to see the car is running well, have fun. On the torque, we made 300ftlbs @5200 (253@~4000)on a PT67 .81 P trim today. That was with base timing, before we really began to dial things in. Unfortunately my PT67 blew with just a couple of dyno pulls on it(brand new), guess I'm just lucky. Warranty will take care of it, but Mazfest is out most likely... I may tow down just to show the car, we'll see. Anyhow, hope all goes well Tomorrow with Dave's 67. Regards, Carl

 

Can you explain that calculation for me?

 

Here's a lousy picture of one of my dyno sheets. This one was actually slightly better than the numbers I posted above, but the torque peak on this graph is due to a signal blip rather than a real reading. The HP was 409.10 legitimately (not a signal blip), however. It's tuned quite rich as you can see, but I am not sure if that was the final tune or not. The final tune was quite rich, too, since I just want to be able to run the car hard and not worry about it too much. I asked Steve to not go after the last little bit just for the sake of having a good dyno number. The dyno wideband was reading a bit different than my own wideband, so I am not sure which is really right. I don't get any ignition break-up, though, so it probably isn't quite as rich as the dyno chart shows. The car pulls like a freight train now, all the way up. I'm a happy camper.

 

Max looks pretty good glad to hear you are happy. That dip in airfuel on the chart directly correlates with your dip in tourque, but if it pulls clean a little extra fuel never hurt anyone,nice to see the nice flat torque curve with a stock intake manifold guess it is possible you could have easily taken the car out to 8500 you would have picked up some more peak hp as well if you did, most people do not like to reve the street cars out this far but a well built motor like yours would love it out there give me a call I wanna chat with you about some other developments.

 

Thanks for posting up, Max. I took the liberty of graphing your R85 chart with Dee's R85 chart & your old Rx-6 chart @ 13 psi.

The Rx-6 was making 12 whp more on average for the 10 RPM points on the graph.

 

Lukus,
PM'd you re your question.

howard coleman

 

Interesting note piano but when I look at the dyno I see something different

-r85 makes more torque from 5800 to the end
-r85 makes more hp from 5900 on
-flatter more desirable torque curve
-power still climbing whe dyno was cut off

 

Howard,

I haven't calc'ed it out yet (and perhaps it would make sense if I just tried), but I was wondering the same thing. If you don't mind posting it here, I bet we aren't the only two people who would like to see how that works.

-Max

 

Also note that my RX6 numbers were 15 psi up to 5500 RPM or so and then it dropped down after that due to a boost control problem I was having (I rigged the stock solenoid and some vents and other stuff to try to control boost with the PowerFC and external wastegate -- that might work with some more trial and error, but I never got it to work.).

-Max

 

Max just out of curiosity what gear did you make those pulls in?

 

I'm pretty sure the runs (both the R85 and RX6) were in 4th. But I'm not certain.

-Max

 

Congrat Max! Very strong number!

I'm about a month behind you at this point. This has recently become extra exciting since the rumors abound on this Forum are that I may have an "extinct" turbo!

 

Extinct??? are they discontinuing the GT40R?

O yeah post pic

 

Max,

When did the dyno operator roll into full throttle? I was interested in the spool up of this turbo but the dyno looks as if the throttle was not dropped until after 4k rpm. Would be nice to see some 20 psi runs out of that snail.

Nice power up top btw,

twok

 

and a/f was sent right off the chart very shortly after

 

Max uses this car for road racing (and street driving too). A 1 -> 2 shift at 8000 leaves you at about 5000 in 2nd. In this spot, the RX-6 dyno does show a small advantage.

However, in every other shift like 2 -> 3, 3 -> 4, and 4 -> 5.... the RPM will not drop low enough to show an advantage to the RX-6 except in the skinny area from 5500 to 6000 or so. And even -that- is only going to be in effect on the 2-3 shift.

I guess the point that I'm making is that for a road race or drag race car, having power between the shift points in the RPM band you'll be using the majority of the race is really important. If I like to road race, I'll trade -20 hp from 3000 to 5500 if I can pick up +50 hp from 5500 to 8000.

On the other hand, if I want that "V8 feeling" I'd go with a smaller turbo (or a 3 rotor hahah) and concentrate on making a sweet midrange.

Definitely looks like the R85 setup is not quite in the "sweet spot" yet... looks like it could definitely be used to 8500 or 9000 (assuming Max's engine and fuel setup is up to it).

 

Wargasm I understand your point unfortunatley I think you are a little quick to pass judgement, to forfill your predictions.

When a car makes 409rwhp@15-16psi and its leanest spot under power is 10.8 and a pt67 makes 399rwhp with a constant 11.9 a/f ratio it is safe to assume that the r85 has alot left.

When performing test it is always important to make thinks equal. i.e. same tuner same dyno etc etc. So if we judge the turbos performance amongst it peers during the day of the tune it gets first place even considering max's car was tuned much more conservative then some of the other single turbo cars there.

It is very easy to take a dyno sheet of a car that is tuned poorly with airfuel off the charts escpecially during where peak torque is about to occur and compare it to a car that is tuned perfectly.

This is the issue I have with your website, anyone can log on there pick a poorly tuned turbo x compare it to there turbo y wich is tuned perfectly and run around this forum yelling y turbo is the best and feel good about it. My point is if you are only satified with the answer you expect it is very easy to keep looking at dynos without knowing anything about how the stest was performed. Many inexperienced car enthusiasts do just that.

I guarentee you max's car will be faster around his local track then it was with the rx-6 when fully tuned. Weather that track is a drag strip or a road course.

I do appreciate your opinion wether I agree with it or not, it has lit a fire under my ***. I have 2 r85 cars coming down for tuning in the next couple of weeks. I will extend the invitation to you and we will video me tuning the cars and then post those dyno sheets for you to compare.

P.S I am also interested in your opinion on how max's torque curve was so flat with a stock manifold and how it continued to rise past 7500 while still using the stock manifold when everyone in this forum said it was impossible.

 

Dee, Actually I was defending your R85 kit, not trying to make it sound bad! I'd way rather have Max's R85 dyno than his Apexi RX-6 dyno.

I also agree 100% that the R85 Maxmobile will definitely be faster than the RX-6 Maxmobile!

As for my website, I hope that nobody tries to take one dyno and use it as the standard to represent ALL dynos of that turbo... Each dyno/car/tuner/setup is totally unique as you pointed out. The point of my site is to gather up a whole bunch of dynos so you can make some predictions.

If I told you my 60-1 made 500 rwhp at 12 PSI you'd know I was full of **** wouldn't you? The reason you know that is because we've seen dozens and dozens of dynos using that turbo and NONE of them make that power at that boost. So the strength of my site is that if you have a lot of dynos, you can make some general guess as to what kind of hp you will make. The WEAKness of my site is that if you only have a few dynos you might not be seeing what is realistic.

So to be clear, I think Max has IMPROVED his car by using the R85. In fact, I wish I had one on my car

 

Actually, the a/f ratio is the same with both cars. The dyno a/f ratio #'s were off on David's car (since that was the first car we tuned). after david's car, I told the shop to replace the filter on their unit and things were back to what I was expected for other cars. Both cars have my wideband connected along with the shop wideband and was tuned accordingly. We replaced a total of 4 filters on their dyno this weekend. Also, the dip at peak torque didn't show on the wideband on the downpipe. It's probably because it was from the wastegate opening causing the a/f ratio to flutuate some during peak torque. I have seen some that richens up the a/f ratio and some that leans out the a/f ratio depending if it was routed back to the downpipe or atmosphere.

 

By posting that comparison, I am in no way implying that Max's dyno will be indicative of all other's who use the R85; however, this is the only other dyno that I have seen besides the ones posted on KGParts.com. Dee, I am not trying to attack your product. I have no interest in doing so, and I'm not here to make enemies. I'm glad that the comments in this thread have "lit a fire" under you. I'll eagerly await a chart of a car which you have tuned. Hopefully, the spool and power will be much closer to that which was "advertised" on the chart on KGParts.com. And just as a point of clarification, did the test car have stock intake manifolds?

 

My "seat of the pants" feel for the two setups:

- The RX6 had a fat midrange, but would fall off at the top end, even after I got the boost to hold more constant. I don't like that, and that's why I got a much bigger turbo this time.

- The R85 comes on slower, but keeps pulling with constant torque. The boost comes back very quick after shifts, too (my guess is that the relatively higher-mass turbo keeps spinning better than the lighter RX6 turbo did). For normal street driving stuff, the car feels strong. Even off boost or at low boost, it feels quite responsive.

It occurs to me that there is a bunch of stuff that you could do to get better dyno numbers. Ice bags, water spray on IC, pump up the tire pressure, etc. We didn't do any of that for my dynos. I don't know what the intake temps were. Maybe I should try some water injection. I have also switched back to the stock main pulley (and I'm still running all accessories except for the air pump), so that probably represents a ~10 WHP difference versus my RX6 setup.

The NPG+ coolant seems to work okay. My peak coolant temp from the dyno tuning was 199F. The real test will be on the track, however. The oil temps got up to 223F, I think.

-Max

 

Dyno sheets (two different runs with similar results) scanned...

 

Those oil temps are too hot, Max. By the way, what boost was that 404 run?

Good numbers, however. That turbo will produce some good figures. The reason for the responsiveness inbetween shifts is what you have said -- the exhaust wheel is dimensionally similar to that of a Q-Trim turbo. Per the larger mass, it has more inertia, and will not deccelerate as much as a smaller P-Trim wheel inbetween shifts.

You could probably get away with a bit better response and drastically lower underhood temps if you have the big turbine housing ceramic coated.

Nice job again,

B

 

Steve thanks for clearing up the a/f issue. I would be interested to see the data log that shows the actual a/f or is the one on th edyno sheet correct. To clear thinks up I know you were requested to tune the car rich I just wanted to clear the record that this car/turbo could easily have made more horsepower. Wich would get it very close to the advertised hp rating and that would be very good considering the test car had no resonated mid pipe much larger air filter and propably more aggressive tune.

Piano the low boost dyno on is with a aftermarket manifold, but the high boost number is with a stock manifold. And maxes car of course is with a stock manifold and the torque tracks the exact same path as my low boost number with the upgraded manifold just a little lower. Maxes dyno does not fall off early like most other stock manifold dyno sheets do. And it is still open for discussion why this is?

As for the fire under my *** I seriously doubt a video of me tuning the car at said 15psi making more power would help as there will always be speculation, but I will try and see what happens!

 

And piano I am sorry for the double post but I could not edit my original. The dyno sheet on the kgparts car was tuned by me, it is actually my car.

This is why I said "I seriously doubt a video of me tuning the car at said 15psi making more power would help as there will always be speculation, but I will try and see what happens!"