Numbers!

 

Forum people are mostly useless. However that's almost the consensus for every real engine builder out there.
Nobody does it anymore, just like the D shaped peripheral ports. "Cool they werkz yo!". Then somebody did some math, backed it up with tests and showed it wasn't the case.
There's proof out there as to why this kind of porting sucks.

 

What? Are you doubting the opinions of such reputable builders as BDC and Karack? I'm gonna tell rotary god on you.

Well, you know what they say about opinions. I definitely agree about variables, I have seen bone stock RX-8's dyno (on the same dyno, on the same day) put down higher numbers than tuned RX-8's with every bolt on available.

Now get your rx-8 and another stock RX-8 on the dyno and post up results or GTFO.

 

Sounds like a plan to me!

There are some very reputable builders out there ....then there are not. Like I ran across a guy who just paid 7k dollars to have his motor rebuilt , and his car is slower than a stock RX-8 after the rebuilt. I'll refain from using that builders name or location.

 

Don't trust anyone rebuilding the engine until you do some research with that person or business. If its a reputable person or business, and had been a reputable builder, then it's your choice to decide if you trust them that much to rebuild your engine, good luck.

 

hahahah.. nice.. BRAP CITY BITCH!!!BRAP BRAP CITY!!

any how... thats awesome! hay 9krpmrx8 I just was talking to you about this..hahah... crazy.. in another post..

 

The brap is gone once tuned.

 

Not all true... my car is tuned and you can still hear the brap, at a deep faster pace because my idle is 1200 rpms. Also look at cars like the speed source RX-8's , that brap is still there and there tuned. My builders car is tuned and his car still makes the brap sound. You can hear his car on start up in the second video I posted.

So not entirely true that you will lose the brap once the car is tuned. Its all comes down to how your car was built 9k.

You can choose to disagree.... but like you said, the proof is in the pudding.

 

Speedsource cars are not just tuned... Peripheral intake\exhaust ports. Of course you get a brap.

 

True... I forgot to include that in my post.
Thanks for clarifying.

 

A well cut well tuned peripheral port will not brap. I would argue that your overall ported area is very close to mine since mine is a complete cut and yours is several small holes. 1,200 RPM shouldn't be necessary with as little port area as you / we have. I'm idling at 900 RPM. I get a slight brap at idle warm up, but with more tuning, that will be completely gone too.

How many degrees of overlap does your port timing induce? It can't be much more than mine...

 

Out of respect of the builder I can't show the bridge. Not trying to be difficult but the alternative bridge is something that only few rotary builders know how to do.Alot of rotary builders have there "secrets" come to find out and don't like to share the wealth. Its been done since the 70's for guys who did not want to go with a traditional bridgeport since a bridge port can cause major heating issues , etc. Yet those who wanted to get more power out of there car without the issues went this route. [/QUOTE]

I never understood the whole secrecy around the porting of rotary engines. If somebody discovers something good, why not share that knowledge with others who could probably experiment, research and take it to the next level?

Now, I do acknowledge that people's hard work should be acknowledged, compensated and respected. That's why copyrights exist

 

Red I can't disclose that , but I will say my ports look nothing like those small ports that was posted in those pics. Those pics show very small holes that the owner or builder drilled strait into the irons. I will say my holes are not drilled strait and the size of my ports can almost swallow the side seals. Key word "almost".

I tried to set the car to idle at 800, 900 & 1000 rpm. No go.
1200 is fine.

 

How much money was spent in all?

 

He could tell you, but then he would have to kill you.

 

All this talk of brap brap - hell mine does that because my neutral switch is faulty . Much cheaper than a bridgeport LOL

 

So does that mean Speedsource, Mazdaspeed, RE Amemiya, etc. all do bad peripheral porting and bad tuning?

 

lol... why would you even assume that. There are different porting configurations even when talking about peripheral porting. It's not just about cutting a hole and hooking up air. At the same time, yes, not all porting is equal.

I love when people pick out little pieces of posts and try to start a flame war over fairly broad statements. As for what I said, it doesn't change the fact that it's true... not all peripheral ports "brap". It's based on the port timing and configuration. Also, places like "Speedsource, Mazdaspeed, RE Amemiya, etc" don't tune PP cars for smooth idle, and street driving. They tune the idle enough to keep them running, and move on. They tune them for mid / top end power that they will be using on the track. A PP is not typically a street-able engine due to how loud they are.

DailyDriver2k5,
I don't understand your comment that you can't disclose the amount of overlap that you're porting is inducing, but whatever. I'm out.

 

Lol, ohhh yeaaa forgot it was super duper secret.

 

I can tell you for a fact that completely stock Renesis ports can flow enough to make 260- 265 fwhp.

Anytime I hear of someone not wanting to show their work because it's a "secret" the only thing I can think of is that the quality of work is too embarrassing to show off and they don't want to be the subject of ridicule. There are no rotary porting "secrets" anymore. There are still those that think there are though.

If there are any pictures of the ports it is very easy to figure out how much overlap there is. The more important thing isn't the duration of overlap but the amount of open port area during overlap that makes a big difference and in an all side port engine there isn't going to be very much compared to a peripheral port or side intake/peripheral exhaust port engine.

I don't doubt that a 2nd gen na that was ported could beat a stock RX-8 in acceleration. You can get 200 rwhp out of those cars with a good streetport and tuning and they only weight 2600 lbs or so.

 

Not trying to be a smart ***, but then why don't they? What's the limiting factor if not the ports?

 

The fact that the engineers had to make an engine with an usable powerband of around 6k rpms is one of the limiting factors. Then comes emissions etc. This is a wide concept, far wider than I think to understand and covers a bunch of aspects, from exhaust ports type to timing, overall intake\exhaust design etc.

 

There are situations where producers of a product or service hold back certain details for fear that other people might reproduce their own or otherwise steal business. The problem is these people don't understand the true nature of what their customers are buying.

Porting, for example, cannot be easily translated through pictures. Sure you can see the ports but there is more to porting than just a picture. It takes technique with the equipment to shape the port and the proper tools to do so.

Point is, you could post pictures on this site, show the overlap or what have you and 99% of the people here won't even be able to do anything with that information. For the others that can, there are only so many ways to skin a cat.

Mind you, I don't think anyone on the forum owes anyone an explanation for anything.

 

Well glad is running good. If we all think alike the rotary would have not been around or lasted this long.

 

X2

I respectfully disagree.

How do you expect people on the forum to behave when confronted with such claims? Big claims require big evidence backing them up.

OP made performance claims about the port job a mysterious person did somewhere.
Where's the evidence?

I think it is totally reasonable for people who read the thread to simply ask for some explanation/evidence.