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

[TitaniumTT]

Originally Posted by NoDOHC

I don't know how you made any boost at all with the charge relief vale open

361 WHp is even more impressive considering that.

If you can make 15 psi, than 400 WHp should be pretty easy.

Not only do you get the fast spooling of the twins, you get good power too (perfect for autoXing).

You have no idea how much you are tempting me to throw a set of BNR twins on my engine instead of the GT37.

The CRV is connected to the end of a 3/4" hose that takes two quick 908 turns and also vents through a filter so it's not like it's wide open but yeah, I'm pretty surprised she was able to do what she did all things considered.

As for the BNR's........... some have made more power with them and others report losing power. I spoke with one forum member recently about his BNR's running full NON-seq with all the valves cut out, holes welded shut and the mani and turbine housings ported...... he made 344 rwhp. Then again in talking with Bryan I believe he said that the highest reported sequential was 412. I would pick up a set of stockers first to see how your setup likes it then upgrade if necessary.

In all honesty though, my next project with be twin GT28's, externally gated hanging of a very similarly prepped 13B-RE in an FD chassis Maybe even GT30's who knows. Need to find a roller first damnit.

Originally Posted by NoDOHC

The reason that I was curious about the NA power is this:
361 WHp @ 6700 rpm = 283 W lb-ft of torque.
283 Wlb-ft * 14.8/(11.5+14.8) = 159 Wlb-ft of torque (which is identical to what my engine makes at 6700 rpm).

Where did all of those numbers come from?

Originally Posted by NoDOHC

This indicates to me that either your engine flows a lot better than mine (which is very possible, as you have the 3rd gen intake and I have a 2nd gen intake) or I can use very simple math to compute the power increase by adding a turbo (power ratio = intake pressure ratio).

I'm running the Cosmo intake, with everything portmatched and cleaned up. I made everything as effiecient as I possibly could specifically for the goal of 400 wheel.

Originally Posted by NoDOHC

The properties of torque at a given air fuel ratio are basically fixed for the fuel type, compression ratio, combustion chamber design and intake port timing (exhaust port timing does not matter for peak power AFR). Since you have identical characteristics in all except for port timing (which is not significantly different) and maybe the compression ratio (I think you have 9.0:1, where my 8.5:1 rotors are machined down to 8.2:1 - but it has a small effect anyway). I would expect our engines to perform similarly for torque vs AFR.

Running 9.0:1 rotors and depending where we land, I MAY be swapping them out for some 9.7:1 rotors. I really want to compare my graphs to Chadwicks when we get the sequentials working. His low end torque was obscene.

Originally Posted by NoDOHC

That is why I thought it was awesome that you were running 13.0:1 AFR (which is about where I found peak power NA) so I can compare. I made 10 lb-ft (6%) less torque at 12.3:1 as I did at 13.0:1. I made a LOT less torque at 11:1 (like 20% less). I intentionally dynoed my engine NA so that I could compare the power numbers with and without a turbo (The goal being to make 2X NA power (430 WHp) at 14.5 psi boost).

I drove up to grab a sensor and was talking to my EMS guru a few days ago and showed him the dyno graph's the car etc etc etc..... told him we were shooting for .8L He was very surprised. I explained the reason and while he agreed with it, he kept pestering me to run her @ .85L just once to see how much she woke up. .85L = 12.5:1 AFR getting close to that dangerously lean part. Lets not forget I warped 2 Apex seals @ 13.5 AFR in one boost spiking pull. I'm alot more comfortable @ .8, but will probably use the overall trim to take a percent or two out and make one pull to see the gains from .8 to .82/.83..... MAYBE. I'd rather have a fat, dumb and happy engine than one that's running a little closer to the ragged edge and one hiccup pops it. We'll see though, she did wake right up though.

Originally Posted by NoDOHC

It almost seems like you are doing a little bit of the development for me (and you are giving me hope that it can be done).

Keep up the good work!!

edit: The above was meant for both Brian and Dave, as I have no intention of discounting or ignoring the critical part Dave is playing here, 361 WHp and drove it home because the tuner knew when to quit.

I love Dave to death, he's a very conservative guy which is nice to know, especially when you think about the things we're asking this little engines to do. When Bill came up and we had that sticking cornerseal, Dave asked what I wanted to do, dyno or no dyno.... you could see the tension leave his face when I said I didn't want to risk it.

Originally Posted by FC3S Murray

I think he is running S4 N/A rotors...not sure though, maybe even S5 N/A.

Man I wish I had a rotary tuner close to home. I have had to learn all tuning via forums and some automotive engineers/ professional tuners. It has worked out so far BUT there is a part of me that wounders if I am missing some "secret" insight that would yield better results. My last "shit" motor felt outstanding at 15 psi and I tuned it to about 11.5:1 keeping the top end within .1-.05 AFR of each cell range.

I am very curious to see what I will put down for power come dyno this spring especially in regards to torque since I have been studying timing correlation and mid-range torque.

Yeah Sean, running 9.0:1 rotors, basically S5/6 turbo compression. Thinking about 9.7:1 depending on where the torque curve falls.

I would say that 11.5 to one is a tad too rich. My EMS guy and I had a very interesting conversation about this on Tuesday.... he by the way does the setup and engine dyno's, or did rather, for Perez Here's what he had to say about running too fat dumb and happy.... in a nut-shell, paraphrased, and I'd also like to add that this is ONE reason I think these engines spontaneously detonate.
Basically by running TOO rich you are leaving unburnt fuel in the combustion chamber, hanging on the rotor, seals, maybe even the housing surface itself. This is fuel, it's partially or completely vaporized and just waiting to be ignited. It's in the perfect environment as well. With the opening of port, incomes more oxygen, and all it needs is a little too much heat, or some exhaust gases to sneak by through the overlap or the trailing sparkplug hole and BAM - autoignition and bye bye.... game over. Is this likely to happen @ 11.5? Probably not unless your plugs are crap but how many people run around in the 9's and 10's? ALOT, how many people pop engines? What are the circumstances behind them? I'd love to study a TON of datalogs from blown engines and see if there is a pattern developing.

Of course he finished this off with..... I've never tuned a rotary to be street driven before though. My world with Rotaries starts @ C16 The guy has an impressive resume though. Alot of big name guys both piston and rotary, drag, circuit and road race all go to him so I think we'll make one pull at .825 and then go right back to .8

[FC3S Murray]

Originally Posted by TitaniumTT

I would say that 11.5 to one is a tad too rich. My EMS guy and I had a very interesting conversation about this on Tuesday.... he by the way does the setup and engine dyno's, or did rather, for Perez Here's what he had to say about running too fat dumb and happy.... in a nut-shell, paraphrased, and I'd also like to add that this is ONE reason I think these engines spontaneously detonate.
Basically by running TOO rich you are leaving unburnt fuel in the combustion chamber, hanging on the rotor, seals, maybe even the housing surface itself. This is fuel, it's partially or completely vaporized and just waiting to be ignited. It's in the perfect environment as well. With the opening of port, incomes more oxygen, and all it needs is a little too much heat, or some exhaust gases to sneak by through the overlap or the trailing sparkplug hole and BAM - autoignition and bye bye.... game over. Is this likely to happen @ 11.5? Probably not unless your plugs are crap but how many people run around in the 9's and 10's? ALOT, how many people pop engines? What are the circumstances behind them? I'd love to study a TON of datalogs from blown engines and see if there is a pattern developing.

Of course he finished this off with..... I've never tuned a rotary to be street driven before though. My world with Rotaries starts @ C16 The guy has an impressive resume though. Alot of big name guys both piston and rotary, drag, circuit and road race all go to him so I think we'll make one pull at .825 and then go right back to .8

I know it is rich but I have two reasons why I think it is safe for me: 1) All we have in MT is good old 91 octane....fun shit. 2) I understand your reasoning with the small amount of unburnted gas from overly-rich conditions and the extra added exhast gas from overlap BUT I would think that the small amount of unburnt gas even if ignited would not be suffiecient or have enough energy too actually cause lethal detonation. Plus, wouldn't the extra fuel actually cool the chamber(although not wise to use an flammable source to cool a piping hot metal chamber) I could be wrong BUT I also am very conservative with AFR's because that is what the "mob" recommends.

I hope random engine popping isn't casued from being conservative