turboR1

I'm at my brother's reading this and laughing. This is Enzo here.

JD, Who ever said it's better because it's bigger? You really seem to think you know everything it's pretty funny... I guess your the expert here since you have your little fan club.. I've never claimed to be an expert on anything, only stating that i actually build and test what i believe works not post bullshit that i've read or heard. All i've ever said from the beginning was thru my experience i've found pp motors work the best. Not make assumptions!

Yes we flow bench rotaries and test them like you could only imagine. Yes any idiot know's a bigger hole will flow more then a smaller one, maybe you should learn how to actually use a flow bench.

I already stated i don't have to prove anything to anybody, certainly not you or this forum.... I've already said enough and don't want to be bothered with you guys anymore. Your the guys who need to have the open mind, not me. I don't sit here saying the bp/pp motors will never be as good as a street port. You guys are. I've said it numerous times already. Build a pp motor yourself then post whatever you find after your testing then maybe i'll take your posts more seriously cause now i just laugh..

RETed

That's true...
...but, once the motor can produce the power, it's just a matter of keeping it:
1) lubricated
2) cooled



-Ted

P.S. - ...and people used to get on my case about the insults and insinuations...some of you need to reread what you're posting and then ask yourself if you really want to be talked to that way. If this is going to stay a purely technical discussion, drop the insults cause it makes you look bad.

Boostn7

I'm glad we're both laughing.....your brothers flowbench/ no template statement was very amusing as well.
I don't make any claims to know everything or to be an expert!!
What fan club ??? -since you claim to built and test turbo-PP motors at over 50psi then many expect numbers or even an explanation as to why the PP is better.
You're taking it personal and getting upset among others.....

Flowbenching ports has very little merit.... its not like we could weld-fill to re-shape or change our runner path like a piston head !!!
The only time I would like to use a flowbench would be to make sure both front and rear rotor are getting equal flow.....(intake issue).
After flowbenching your ports, how do you shape the final port on sideplates to maintain exact port timing on both prim and sec ports ? by eye ?
Everyone else uses a template for a good reason. I personally have 3 templates for different street-ports and 1 for bridge-port.[/QUOTE]

I already stated i don't have to prove anything to anybody, certainly not you or this forum.... I've already said enough and don't want to be bothered with you guys anymore. Your the guys who need to have the open mind, not me. I don't sit here saying the bp/pp motors will never be as good as a street port. You guys are. I've said it numerous times already. Build a pp motor yourself then post whatever you find after your testing then maybe i'll take your posts more seriously cause now i just laugh..[/QUOTE]
I respect that...your choice to educate or to be educated !

No one is saying that the BP/PP motors will never be as good as a street port !
In the past, the majority believed the actual opposite, BP/PP were the only way to make big hp numbers. Still remember when ~400rwh was a huge accomplishment from a 13B and considered to be tapped out. Now you have full street cars capable making ~700rwh with the right combination on race gas.

WTF !! You're the one on here with all talk and no actions ....tons of R&D, lots of dyno pulls, lots of flowbenching, lots of boost and yet NO technical explanation, dyno sheets or any other way to back up your argument.
Keep on laughing......since we're all laughing among our selves..

JD

Boostn7

There was a few PP+turbo cars years ago but I don't see any now.
Can you give me some more info on La Fabiola ?

PP+turbo is mostly from Australia....the land of big turbos and huge A/Rs..
I had a link with the fastest cars from Australia, see if I find it.

JD

pluto

Eventhough, I don' t have much experience with P-port turbocharged applications, I do have a few experience with the 1/2 B-port turbocharged cars. "In my opinion", B-port turbo engine works great under 25psi, they make more hp at lower boost compared to street port and faster spool up due to overlap. However, once you get above 25psi of boost, there're very little gain between B-port and SP engine. To top that off, I notice more reversion come into play where during each shift (fast or slow), the engine would bogged down for a split sec before it catches again. I never had this issue before in a SP engine but it is very pronounced in the 1/2 bridge engine. Also, it only occurs if I run more than 25psi. I think that if you use the right tranny (auto, Power glide, G-force) where you can stay on WOT on the entire pass, you won't notice any reversion but on a stick shift where you have to let off the gas pedal, I don't think it is ideal.

Steve

enzo250

the problem you experienced steve is not engine related... Mostly likely your turbo selection. That's the key to everything.. Did you monitor backpressure? The power you experienced under 25psi will continue once you figure out which turbo the motor wants.

G_RIDE

This thread isn't as usefull as you would think... I have yet to hear any one speak in terms of actual port timing in degrees/radus. there is nothing technical or worth while in this thread, just a bunch of... I tuned this or that and this is what i got...but WTF was it? oh a half bridge ok well what was the port timing for the intake and exhaust, how big were the ports... when did they open/close. This thread will go no where until real facts are laid out

Owen

iTrader: (1)

Pluto, car to share what setup you had on the 1/2-BPT? What size turbo, ports, etc.
Thanks

xtremertr

Back pressure is the key to any turbocharged application wether it is BP PP or just a street port, Enzo maybe you can elaborate a little more on your answer or post various dyno sheets of the PP engine you are working with and how the results changed based off of back pressure, port timing etc etc. I am not trying to be a "Pain" i think it would be nice to take thread to the next level technically so we can all benefit.

KNONFS

iTrader: (14)

It a new full chassis car\engine, it debuted in mid 05, and managed to run a 7.72 @ 173MPH on one of its first pass; however I have not seen or heard from it ever since

You can see it and get more info here:
http://ausrotary.dntinternet.com/for...ic.php?t=80472

BTW - Per one of our memebers, it ran a 4.94@154mph in lakeland FL.

enzo250

Yes you are correct.. Also each turbo is different as well. Some require more bp then others to maintain desired boost levels.

Your not being a "pain" but i'm not going to post any info/dyno sheets on the motors i'm working on. Taking this thread to the next level won't happen due to some know it alls on this forum. How can you when whatever you say that they dont understand they'll say it isn't possible.

I've learned something very important a few years ago and some of you should pay close attention to this. " No one knows everything in this industry and when you think you know it all your in for a rude awakening". Things change everyday and you have to learn to adapt. Things people thought weren't possible years ago found out later on that it wasn't true and were able to figure out a way. they did this by trying different things and having an open mind. I'm lucky enough to be surrounded by ex Pro Stock drag racers and i've learned alot from them. These guys have tried everything and there still learning to this day... We on the other hand expect everything on a silver platter....

I appreiciate those who do have an open mind and want to learn so i will help anyone who's currently working on a turbo/na pp motor with any questions they have. And what i mean by that is i'll help steer you in the right direction but don't come out and start asking for specifics like port timing, turbo sizing, etc and expect everything on a silver platter cause that ain't going to happen.

pluto

I tried a few different turbos and they all yield the same so I just live with it. I had T66, T70, T72, GT42, T80, and now the T88(GT47) which I haven't try yet but will let you know how it goes.

xtremertr

I respect racers not wanting to share thier results, do you at least have any et's or mph from some of the cars/engines you built, if not you will prob continue to have problems cause without proof it's just fuel for people to bust your *****.

peejay

Aw come on. "People who say it's not possible get interrupted by those who are doing it." Nothing better than first-hand evidence on your side.

Hell, it's half the reason why I built a P-port in the first place. (The rest was, well, why not?) Naturally, everyone (who never had one) KNEW that it wouldn't idle below 2500, or make any power below 7000...

It wasn't too long ago that everyone KNEW you couldn't put a turbo on *any* rotary. After that, everyone KNEW that you couldn't put one on a ported one. Etc.

enzo250

Your getting there. Get a backpressure sensor on there and let me know what your seeing. Throwing turbo's at it gets expensive quick. As you probably found out already...

rotarygod

iTrader: (1)

This is a friends findings so take it as you will and don't ask for alot of specifics. A few years ago my friend Marcus (who used to be well known on here under the name of TURBOSTREETFIGHTER) had a half bridge 13B race car running on alcohol. He had a custom built intake manifold with only 3 intake runners and a huge plenum. It was a 13B-REW block with only the primaries (yes the primaries) bridgeported. The secondaries were streetported. He was running a standalone ecu (Wolf or Haltech, can't remember). He tried several different combinations of turbo compressor wheels, trims, a/r housings, etc on the dyno. What he found is that even with a very large exhaust side such as a Q-trim and large a/r housing (again don't remember specifics), he couldn't go past around 22 psi on his setup. He had an exhaust pressure probe. He found that he had around 24 psi exhaust backpressure with 22 psi intake pressure. When he cranked the boost up higher, all he got was heat and even more exhaust backpressure. He never made more power and would even make less as boost passed a certain mark.

He then tried using 2 smaller turbos as dedicated twins. He never gave up the specs on them so I don't know what they were. They were T3/T4 hybrids though. He could actually get less exhaust backpressure than intake pressure with this setup. It seems impossible at first but a little understanding of thermodynamics and what is going on in an engine can show how this is quite possible. He made more power at lower boost with this setup than he could with higher boost on a single turbo on the same engine and it spooled up faster. He was in the process of taking it up over 30 psi when a fuel injector failed and killed that engine. After having small failures not related to the block itself kill several engines, he got out of rotaries so he never pursued it further.

He only had issues because of the port overlap and it actually wasn't that much compared to some other setups. He actually had great results with lower boost settings and this port style than with more conservative porting styles and the same boost. The advantage was only up to a point though. Once it got high enough, he hit a brick wall and needed to treat it differently. The more overlap you have, the more important reduced exhaust backpressure is to making power. I have no doubt that any porting style can make huge power but it doesn't mean you can take the same approach to each setup as you could with another. Just because something works one way on one engine doesn't mean it will work that way on another engine. The logic that a p-port makes the most power on a naturally aspirated engine so it must be the same way on a turbo engine is extremely flawed logic. Not saying it can't make more power. Just pointing out the error in the thinking.

Which one is better? That depends. It's at least an honest answer. How is each one setup? That's more relevant to answering the question.

pluto

Ya, it definately gets pretty expensive over time experimenting with different turbos. The new setup I have now is totally different than my old setup so I really have no idea if I actually fixed the problem or not. Besides, my tuning method was totally different back then than what I know now so I'm sure that I can fine tune the map to compensate for it. On my last setup, based on my calculation, I was making close to 700-720rwhp at 28psi of boost and a 75 shot of n2o. This is based on my 1/8 mile time interpolate into the 1/4 mile time based on a 30-33mph gain in the last 1/8 mile. I ran a 6.40@114mph in the 1/8 with a 1.62 60' because of a slipping clutch. My car weights in at 2975lbs with me in it. I think n2o is what really created all the unwanted back pressure but once you start using it, you just don't know when to stop.



Steve

Boostn7

Someone asked for port timing...so here's some that are known:

2nd/3rd Turbo 13B:
Intake Opening= 32° ATDC, Closing= 50°ABDC
Exhaust Opening=71° BBDC, Closing= 48°ATDC

Street-Port (Racing Beat)
Intake Opening= 25° ATDC, Closing= 60° ABDC
Exhaust Opening= 84° BBDC, Closing= 48° ATDC

J-Bridge Port(Racing Beat)
Intake Opening= 115° BTDC, Closing= 72° ABDC
Exhaust Opening= 88° BBDC, Closing= 57° ATDC

Peripheral Port (Mazda Factory housing)
Intake Opening= 86° BTDC, Closing= 75° ABDC
Exhaust Opening= 73° BBDC, Closing= 65° ATDC

One of the main concerns with P-ports was overlap...quite helpful in NA form but when turbocharged results are different. If intake pressure is greater then exhaust pressure then intake pressure will escape thru exhaust port. With exhaust pressure higher you get whats called reversion which is exhaust gas pushed back up intake diluting the intake charge and lowering engine's efficiency.

Someone compared the overlap with a piston motor !!!
Keep in mind that a rotary spends 1.5 times to complete same "stroke". (180° vs 270°) vs a piston motor at any rpm.

Now we see why some racers are going to much smaller PPorts and moving them up as far up as possible.

Look at Ken Scheepers.....all year with a turbo-PP engine built by the best and now he's deciding to go sideport(bridge) !!! WHY ???

JD

Boostn7

Let me clear something up....
I the past I always believed the P-port to be the superior port in NA & Turbo !
In NA form it continues to dominate but when turbocharged it has become a headache for many racers for many apparent reasons.
You are entitled to your opinion and don't have to prove anything...

Anything is possible....just a matter of trying, trying again till it happens:-)
How many times was I told-"impossible !"

JD

13btnos

iTrader: (1)

It's not in who builds the motor as it is more to who tunes that motor. Look for example the motor in the RX8 Major League from Puerto Rico no one has been really successful with that 3 rotor PPort setup and they were running it with one of the best systems out there a Motec. And Siguel gets a hold of it and switches to a Microtech and gets that thing dialed in running sixes before it even has 10 passes on the car. Like it was stated before you will not find these major racers trolling around in these forums only way your going to get info is straight from their mouths or going out to the tracks and talking to them. If you do enough searching the answers are there and like all those that claim things to be impossible well impossible is not in some peoples vocabulary. The PPort turbo setups are in their infancy but there are quite a few people around the world, more than you can count with your fingers, that are willing to sacrifice their time and whole shitload of money to prove people wrong. And that's the beauty about our engines we are always out to prove someone wrong. Atleast for me that holds true.

z8cw

First of all great threat

But since we just going going in circles maybe we can focus a little on the regular people. For myself I like to have a fast car 10s, possibly 9s, for some weekend racing. Some of us like to still drive the car on the road as well.

So what do you think is the better set-up (I know better is subjective) but what isn;t.

1. side port, 600hp, 29PSI, 7300rpm
2. brige port, 600hp, 23PSI, 7300rpm
3. pport, 600hp, 20PSI, 7300rpm

But since we all won't leave good enough alone, which motor will run longer, more reliable and has more potential?

CW

RETed

There's no one miracle answer that's going to satisfy everyone.
With the higher overlap (SP -> BP -> PP), you're getting a narrower power band, so it depends on your set-up and what kind of racing you're going to be doing.

Implied is the lower boost level at the same power level, so that's already in favor of "reliable", but that's ignoring a LOT of other factors.
"Reliable" would also throw out most BP's due to their higher failure potential.

I think you're asking too broad of a question to get a simple answer.

Just look at the numbers you threw out, it's almost "impossible" to hit them especially with such a "low" RPM level.
BP's gotta go up to 9k (or else why run a BP in the first place?), and the PP should be spun to at least 10k!
If you want a 7.3k redline, the BP is just starting to come on strong, and the PP is barely chugging!


-Ted

z8cw

I left it that vague so we can get more opinions. As for needing to spin the engine that high, again I think this is very true for NA set-ups. For a boosted application you can make decent power without needing to rev so high. Sure you can and take advantage of an extended powerband, but that comes at a price again.

13btnos

iTrader: (1)

This has been done PPort 420rwhp with only 9psi boost @ 7300 rpm's on pump gas. So who says you have to spin a PPort up high to make decent power. You aren't even straining that motor at 7300 rpm's. http://ausrotary.dntinternet.com/for...=77936&start=0

RETed

I guess you missed the whole overlap thing in this thread.


-Ted