93 R1

Take it easy guys.



When you say "back cutting" Is this what you are refering to:

scalliwag

Putting Brian on the spot like this a total bullshit. He's a big boy and as his last post shown he can hold his own.

But I will tell you what I do know. I know the motors I have seen Brian build like in Tony's car have proven his work for him. He is also a guy that will go way the hell out of the way to help people, even at least one that blew his motor because he was a dumbass and a broke dumbass on top of that.

He shares his ideas and how he actually does things that get the power he is able to get.

Hell most builders would not share that info and since they don't they are less susceptible to someone being over critical of their work and trashing them over it.

Brian will be the first to tell you that he learns new stuff all the time and is ALWAYS willing to listen to new ideas. He is one of the least confrontational people I know and not because he is a puss, but just because he is a good natured person.



This was very uneccesary and even if you don't think he does it to your satisfaction Ted there are ways to be diplomatic. Your point was structured in a way that everybody took offense to it. It was pretty much an all out attack.

BDC

I'm fine, Justin.



You're right on the picture, by the way. Someone pointed this out to me during the summer time last year when I was in the first stages of practicing and learning all about BP stuff. Although I don't know to what measurable, practical effect having the short radius (underside, underneath the inner water jacket o-ring) "backcut", but I suspect it will have an effect for the positive most definitely. If it's left with a 90 degree bend, then I don't believe it will work as well.



B

scathcart

Only one way to find out...

I'll give it a shot on a secondary/auxilary bridge 6 port engine. I'll try disconnecting the secondary throttles... it should work.

You could always just machine a plate to go between the UIM and LIM, with only ports feeding the primary runners, and then pull the secondary injectors leads.

It'll be interesting.





Does secondary-only porting have an effect on emissions testing? With FC manifolds, it should have very little effect, especially on idle output.





Brian: I have always used a die grinder with carbide bits for my porting. Would you mind posting a pic of the rotary tool and all of the bits that you use? I'm curious.

Thanks.

j200pruf

As far as getting a bridge through, I had this idea for a secondary/aux bridge. Bridge the Secondayr and Aux ports, leave the promarys close to stock. Then machine a plate to go between the inkate manifold that would have throttle stops in the runner for the secondary and aux ports, operating like the Euro butterflies.

I figured I could get near 230wrhp and maybe get it through DEQ.

Sorry to hijack Brain.

RETed

I know I'm not the most "PC" person out there.

If it came across as a personal attack, then I apologize - this was not the intent of the reply. I wanted go get a valid discussion on the pro and cons of BDC's BP, and that's it. The reply was sent when I had to wait for a bunch of idiots building maintenance people for their annual pipe inspection, and I hadn't slept for over 30 hours - I apologive for coming across a little rough there.



I guess it all comes down to personal philosophy on bridge porting. I don't normally do them, and I don't like doing them on street, daily driven vehicles. I don't like the longevity question, and blowing a motor due to a failed bridge is not worth it in my book (for most people). I normally advise against it only in extreme circumstances. With that said, I have two BP projects under covers. One is definite, and it should be up and running within the next two months. This car is going to run a "secret" BP I'm going to try that should solve the longevity question; I want to see if the car will "run the numbers" and work properly before unveiling any info on it...if anyone cares.; the car is going to be an all out drag car. The other BP project is for a huge HKS T51R Kai 13BT, and the shop owner is busy getting his new shop in order before giving me the go ahead with the BP work.



BTW, that pic that I posted is a generic BP pic out of a Japan magazine. I dunno who did it or what kinda power it makes, but it's not my work. It's the same pic in my website.



Bottom line, we have vastly different views on what a BP should do, and I'll leave it at that.





-Ted

93 R1

Ted,



In your opinion what should a bridge achieve over a large streetport? I'd like to know.

RETed

I don't know if tread jacking this is right, but I'll welcome to replying in a separate thread if another one initiated.



This is my philosophy about BP's...



The BP will compromise engine life - I'm sure we are all in agreement here.

I haven't seen proof of any BP design that will come close to what a SP longevity has - which is is basically 0% failure. This means that you're going to end up with a damaged motor - the question on how much damage due to the broken bridge depends on how good your luck is. With that said, I believe if you're going with a BP, why not go all out? The only compromise design is a "half" BP for those people who want a little more streetability in their engines. The failure of a half BP is still going to kill the engine just as much as a full bridge, but you do cut your chances in half. I think all bridges would've failed at around the same time (within 10,000 miles of each other), if given the chance - if they don't, then quality control and repeatability on porting technique is in question.



I would like to see comments by some of the more well-known porting gurus like Judge Ito, but I wouldn't be surprised in non-involvement on such a controversial thread. The information I've gathers on people who do BP's on a regular basis have formed my views on what a BP should and should not be; I trust these individuals, because they give me the straight-up info without all the sugar-coated BS. I've run BDC's pics of his BP's, and they have all confirmed my suspicions. I know it's not the nicest thing to do on a forum to challenge people (especially "gurus") on their positions, especially on their work - it always ends up being taken as a personal insult. I welcome BDC's (or anyone elses) comments/opinions/insults on MY work at any time - this is the only way I can *learn* when I can or cannot defend my work. I'd like to think I got a pretty decent grasp on BASIC engine dynamics, and anything that goes over my head I turn over to friends who are BSME grads.



I've known BDC for a long time, and we go way back... It hurts me to see his position stated on my challenge to his BP work by putting up the age-old "I've hit XXXhp (499 in this case), what have you done"; I find this defense a little lacking as anyone with a big turbo and a little knowledge could do this. So what if I beat 499? To me, this doesn't make me better than BDC, but does that legitify (is there such a word?) to BDC that I'm better? I would hope not, but why issue such a challenge in the first place? BTW, if it makes any difference, I do have a twin turbo project in the wings that should break 500rwhp on pump gas - I think that 499 run was made with a race gas mix? I think both [B}BDC[/B] and I started out FC3S/rotary engine experience at about the same time, with similar experiences going through FC's and Haltechs. He's lucky he got to mess around with bigger projects, as losing my job 3 years ago and losing almost all my stuff (tools, car parts, etc.) to some really stupid involvement with some bad characters have left me in a big hole at this point in my life; I'm lucky to be able to be involved with FC's/FD's and rotary engines in general in this point in my life through some very good friends, but having no money myself really cramps my R&D on potential projects.



I'd like to think my theories on rotary engines are made through objective thinking and reasoning. It would be nice to confirm them through objective testing, but my current financial situations limits that right now. If I come across other people's theories that I do not agree with, I tend to vigorously challenge such positions. I guess I'm doing it a little too vigorous, as people do get offended! Hell, I've cross paths with Judge Ito on some of his postings and pics on the other forum, but they have been cleared up after an initial flurry of miscommunication; I hope he's still not mad about that. I am a supporter of Judge Ito's work and theories, as many of my experiences have mimic'd his advice - I still think he's giving away too many secrets though! Case in point, I stumbled into the side seal problem by accident, and my intake ports have a very shallow angle on the closing end which is solves this problem; I was surprised to see the pinned post by Judge Ito at the top of this section addressing that very problem!



Anyways, I'm rambling too now...





-Ted

Boostn7

What's up fellas !!!!



Onle a few remember me running a half-bridge in my TII many years ago.

It was a full half-bridge w/ big street-ported sec's, rotor housings were notched and 45 degree of "back-cutting" was done.

Longevity was the same as my SP......had left plenty of material for the bridge. Motor ran for 10 months as a daily driver, a bit over 8k miles and ~440-450 rwh dyno pulls on pump gas(94).....later 495rwh (race gas). On that 495rwh run I put down 418lbs of torque.



Motor made nice torque and power for the boost...but I later realized I could not take full advantage of the bridge port without replacing the OEM TurboII intake and spinning the motor higher rpm(8-9krpm). Hmmm... FD intakes do flow more.



It sounded like a killer in the street.......but at the gas pump I would always get the same question.." needs a tune-up, huh??"



My .02

rx7_turbo2

If it's so easy where's the proof you've done it? Where are the pics of your porting?



You always attack other people like this, but when the tables are turned you use the same old excuses every single time. "Anybody with a big turbo can do it" "I'm not about that high hp stuff" Give me a break. Shut me and all the others up Ted, show us once and for all what you've actually done.



Up until this last bit of crap this thread had some good info (if you knew who to listen too) I don't think there is 1 set way to port a motor, BDC explained the reasons for the type of porting seen in the first group of pics and it seemed to make sense to me.