TitaniumTT's I hope I make it to DGRR '09 Build

[TitaniumTT]

Alright, well, I guess I better update this.

Finally had a clean dyno session. No fuel pressure problems at all. Started off by running on WG and fartin' around with the various valves and solenoids. For those of you not familiar with the Sequentials, here's a rundown of whats involved.

Turbo Control Valve - TCV located in the exhaust Mani - allows the full exhaust of the rear rotor into the 2ndary turbo
Charge Control Valve - CCV - Located after the 2ndaries compressor to keep the primary from backspooling the 2ndary
Charge Relief Valve - CRV - Vents the 2ndaries boost until it's ready to come online.
Pre-Spool Valve - PSV - works like a wastegate to send exhaust energy to the 2ndary to start spooling it up.

First thing I did was take my spare 2Bar MAP sensor and instal it after the 2ndary compressor and before the CCV so we could log what boost the 2ndary was producing. The only problem is that becuase of a slight pressure drop and us eventually running 14 lbs, I kept "overrunning" that MAP sensor and throwing an error, Oh well, just had to reset the errors between pulls. Started off with the transition occuring @3800 RPM's We made about 20 pulls on Tuesday and got the transition down to almost nothing - .15-.25s of nothing. On the street it feels interesting. Response is instant. The car just wants to take off! I was running ~55 on the highway, ~2700 rpms, blip the throttle to pass someone on the right and BAM! 15lbs of boost and the car just takes off. I'm making 250ft'/lbs by ~3200 rpms and I bet that would be lower. Dave was launching @ 3k on the dyno. In other words, the car goes from vac to 15lbs in ~200-400 RPM! From one log
Time = 5:07.448
TP = 40%
MAP = 90kpa
RPM = 2867
Time = 5:08.583
TP = 100%
MAP = 175kpa
RPM = 3226

So in the time of 1.13 seconds I gained over "12psi" (quoted becuase some of that is vac) in ~350 RPM's. Boost falls a little as the PSV opens to spin the 2ndary, the transistion is a blip and then hold on, torque just takes off.

Since the dyno I've moved the transition to 4000 and started messing around with the valves a little. In the discussions before we even started, Dave and I both came to the realization that the roller is going to slow everything down to the point where it would need to be dialed in on the street. It was great however to get the fuel map dialed in which was almost spot on. Even though we were venturing into areas of the map where we've never been before, our math and logic was almost spot on. A good feeling actually.

So we played with the CCV, opening it earlier or later proved to make the biggest difference in the reponse. We would either get a HUGE surge in torque, which just felt odd, or a slight dip during the transistion and then boost built again. This is what we opted for. After 21 runs (and 101 runs total) it seemed like we were chasing our tails and not getting anywhere, so we decided to call it for the night and head back after some street tuning.

What I discovered on the street was a little dissappointing at first. The dyno puts such a load on the engine that it would actually spool the primary faster. So while on the dyno we were seeing 11+lbs of boost, on the street, in the lower gears, I was seeing about half that. Easy fix, reduce the duty of the PSV becuase it works basically like a WG and viola, 12-15lbs on the primary.

I also incorporated something else that was pretty interesting, WG duty = TP vs RPM. So the more I open the throttle, the more the WG solenoid increases the boost. That made the single biggest difference in the way the car drives. She's MUCH less twitchy on me which is really nice. Much more driveable. She feels like a high-strung V8. No problems rolling through stop signs in high gears and 2k RPMs. Not at all like the previous rotaries that I have driven, this one is DRIVABLE

So the weather is not cooperating with me tonight or I would be out there tonight testing my new idea of surging the 2ndary a little more by PWM'ing the CRV to build more boost in the 2ndary and lessening the transition dip.

Something to try out tomorrow night if the weather, and Alex cooperate. We're heading North to go pick up his LS1.

So there it is, the car is done, and in 10 days or so she'll be stripped down and tossed on a rotisserie Just like I predicted in May.... Oh well.

FWIW though, I am glad I stuck with it despite what everyone said on the evil forum about the twins. They were all wrong, with the exceptions of a few who understood why two smaller turbo's > one large single.

I need to find some GT35R dyno sheets - what everyone told me to do, and compare them to mine and post them up. Show me one single that makes 250ft/lbs by 3200RPM's

[WE3RX7]

Originally Posted by TitaniumTT

I need to find some GT35R dyno sheets - what everyone told me to do, and compare them to mine and post them up. Show me one single that makes 250ft/lbs by 3200RPM's

Sounds like a good challenge to me. I'll take that bet


Congrats man - sorry I missed out on all the fun at Dave's. In the spring when my engine is in the car and ready to roll, I'll probably abuse Dave's dyno as well. We will definitely need to compare notes and I'll need some Motec schooling while we're at it

[scotty305]

Originally Posted by TitaniumTT

....
Turbo Control Valve - TCV located in the exhaust Mani - allows the full exhaust of the rear rotor into the 2ndary turbo
Charge Control Valve - CCV - Located after the 2ndaries compressor to keep the primary from backspooling the 2ndary
Charge Relief Valve - CRV - Vents the 2ndaries boost until it's ready to come online.
Pre-Spool Valve - PSV - works like a wastegate to send exhaust energy to the 2ndary to start spooling it up.
...
So we played with the CCV, opening it earlier or later proved to make the biggest difference in the reponse. We would either get a HUGE surge in torque, which just felt odd, or a slight dip during the transistion and then boost built again. This is what we opted for. After 21 runs (and 101 runs total) it seemed like we were chasing our tails and not getting anywhere, so we decided to call it for the night and head back after some street tuning.

Very interesting. I've also got a standalone that will allow me to control these valves independently, and so far I've got the CCV, CRV, and TCV solenoids all switching at the same RPM (4000 works well so far). At low RPM, the WG solenoid is about 90% duty and the PSV is used for boost control.

Your post above suggests you might be opening the CCV before or after the TCV and CRV?


By the way, regarding TPS-based boost control, I've heard of tuners using this as a way to compensate for throttle airflow saturation. If your throttle allows about the same airflow from 70-100%, increasing the boost target at 80, 90,. 100% is one way of giving the throttle a nice linear feel. I've tried this on my car and the feel is pretty nice... I imagine it's a bit more important with big-power cars like yours, mine isn't even putting 300 to the wheels.

[TitaniumTT]

Originally Posted by scotty305

Very interesting. I've also got a standalone that will allow me to control these valves independently, and so far I've got the CCV, CRV, and TCV solenoids all switching at the same RPM (4000 works well so far). At low RPM, the WG solenoid is about 90% duty and the PSV is used for boost control.

First, which standalone are you using?

How is your WG plumbed? If you are lowering duty to increase boost, I would think about changing that around. That is the original way I had it but upon more thought, I decided it was a bad idea. If the solenoid goes dead for whatever reason, your boost will spike out of control after the transition. Before the transition, you're right, the PSV does a nice job of controling boost, this is exactely how I have it. I would like some sort of closed loop feedback and I am still toying with it.

Originally Posted by scotty305

Your post above suggests you might be opening the CCV before or after the TCV and CRV?

Yes, I am opening the CCV partially and beginning to close the CRV before the TCV kicks over. It's all based on RPM's and TP at this point. I may take a break and revisit it in the spring but right now, it's damn smooth. On low boost the transition is virtually flawless. In highboost though it's more like a 12-12-15 pattern and when that 15 hits, traction is gone in 1st and 2nd by 4200 and in third around 6 it usually breaks loose. These are RT615's sized 255/40/17.

My low boost and high boost can be adjusted with a dash mounted 9-posotion mini switch. I love the MoTeC

Originally Posted by scotty305

By the way, regarding TPS-based boost control, I've heard of tuners using this as a way to compensate for throttle airflow saturation. If your throttle allows about the same airflow from 70-100%, increasing the boost target at 80, 90,. 100% is one way of giving the throttle a nice linear feel. I've tried this on my car and the feel is pretty nice... I imagine it's a bit more important with big-power cars like yours, mine isn't even putting 300 to the wheels.

Yup, that's exactely how I have it setup. My MoTeC guru gave me that little tip to linearizre the throttle. You're right, increasing the throttle from 70-100% has little to no effect on the power to the ground. By adding that axis in the boost control, it gives a much more linear pedal. Right now, the table is just that, linear. At lower RPM's it doesn't do much because of the WG spring, actuation etc etc/ I need to play around with it a little more. I think in the end it will look more exponential until 5k and then level off. We shall see.

I'm interested in your project. Care to share a little?

[scotty305]

I have an AEM EMS, stock wastegate, stock solenoid and vacuum routing... I think higher duty cycle yields higher boost. I'm not completely sure; there's an 'invert duty cycle' option in the software so I might have enabled that and forgotten about it a while ago.


I hadn't thought to control the solenoids that way (it's my understanding that the stock ECU switches them all at the same RPM), thanks for the info.


Didn't mean to distract from your thread, more info about my setup here:
http://rotarycarclub.com/rotary_foru...ead.php?t=5496

[TitaniumTT]

What looks like the NICEST GT35R dyno sheet that I can find




What Dave did. I checked the logs and the last run, run 101 was about 14lbs falling off to about 13


So @ 3200 RPM, I'm making TWICE the torque of a T3 GT35R with an equal length runner mani

By ~46-4700 RPM, the GT35R has caught up. At the end of the run the GT35R is making 25hp more (than my best 405 run with more boost, we never got back into the high 70% duties that we were running before, instead we stopped at 64 - it was after 6 o'clock.) and only ~15ft/lbs more than my best. I like my twins. That is all.

[Nismo]

Someday our cars will meet and they will fornicate, hopefully producing smaller, yet more powerful offspring.

My car with be the giver not the pillow biter.

[EJayCe996]

*High energy orchestra music*
A CHALLENGER APPEARS!

[Nismo]

Originally Posted by EJayCe996

*High energy orchestra music*
A CHALLENGER APPEARS!

Well I don't know about a challenger, Brian is very talented, and I could never match his attention to detail, mine will be much less complicated compared to his twin set up.

[TitaniumTT]

Originally Posted by FC3S Murray

Well played sir, well played

I am stoked for you Brian. Determination is a mother fucker and you my friend have that, patience and....a deep pocket book Congrats!!

Thanks Sean. My pockets aren't that deep anymore. I need to return to my whoring days to build that back up Maybe I will be the bitch in Kevin's scenario

Originally Posted by Nismo

Well I don't know about a challenger, Brian is very talented, and I could never match his attention to detail, mine will be much less complicated compared to his twin set up.

Thanks Kevin, I'm OCD, what can I say. It seems to be infectious too. I keep telling my soon to be partner that he's "Coming along quite nicely" :lol Of course he answers with, "shit, it's better to [sacarsm] index every single little screw[/sarcasm] than listen to you bitch about it for days on end and eventually watch you do it yourself." He is coming along quite nicely though

Ya know, indexing the screws? So that all the heads are pointing at the same angles? If you have a line of them they look like +++++++++++++++++++++++++++++++++++++++++
as opposed to ++XKKX+XKX++XKXKX+XKKX+XKXX+XKX+X+XKXX+X+XKX+XXKKX +X+KKX+
If it's not a right angle it's wrong, shit like that, yes I'm insane. I've also been known to repaint hoods 5 times until I'm happy.

[TitaniumTT]

Originally Posted by Nismo

Someday our cars will meet and they will fornicate, hopefully producing smaller, yet more powerful offspring.

My car with be the giver not the pillow biter.

Did you just call me a Bitch?

Originally Posted by EJayCe996

*High energy orchestra music*
A CHALLENGER APPEARS!

Details? as in NOW

[WE3RX7]

Originally Posted by Nismo

Someday our cars will meet and they will fornicate, hopefully producing smaller, yet more powerful offspring.

My car with be the giver not the pillow biter.

Wow - thats a scary image. DGRR 2011 it is then, 3 RE FCs in the ultimate circle jerk of power...

In all reality, my setup will be more similar to yours than Brian's with one unique difference

[TitaniumTT]

Originally Posted by WE3RX7

Sounds like a good challenge to me. I'll take that bet


Congrats man - sorry I missed out on all the fun at Dave's. In the spring when my engine is in the car and ready to roll, I'll probably abuse Dave's dyno as well. We will definitely need to compare notes and I'll need some Motec schooling while we're at it

Sounds like a plan to me Bill. I'll definately venture out for that. I'll actually be there on Wednesday before Turkey Day to whitness a friends '99 Seq FD put down some numbers, and also to go for one last cruise of the year to PA. I just realized the date, I have like 12 days of FC joy left :sniffle:

Let me know in advance when you're going to Dave's in the Spring. I'd love to be there. I'll be strapped down a few days before DGRRX as well. Replacing my LS1 coils with LS2 Yukon coils and swapping out injectors as well. I'm pretty maxed @ 90% duty. I originally had planned for ~350-375RWHP. I enjoy exceeding goals

Originally Posted by WE3RX7

Wow - thats a scary image. DGRR 2011 it is then, 3 RE FCs in the ultimate circle jerk of power...

In all reality, my setup will be more similar to yours than Brian's with one unique difference

HA! I'm staying away from you wierdo's So Bill, what's the big difference? Huh huh huh??? Tell me tell me tell me tell me.... is it the ECU.... which one... details damnit.

[FC3S Murray]

Well played sir, well played

I am stoked for you Brian. Determination is a mother fucker and you my friend have that, patience and....a deep pocket book Congrats!!

[WE3RX7]

What size injectors are you running at 90%?

If all goes well, the engine should be rebuilt and in the car in March. I would like to get some base tuning done prior to DGRR (even though my FC wont be comign).

I will be going to Dave's with the irons prior to the engine build though to discuss those fun ports he mentioned last time I was up there...

I also was considering getting him to rebulid my trans and cryo some things, dunno though -we'll see how time/money permits...