DON'T Port Your Mazda Rotary - BridgePort of Broken RX7 Dreams

There is a huge difference between a professionally ported engine, and a backyard port job. There is a reason that the highest mile rotary engines are bone stock.
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[@RIBZOH]

A wise man once said “NO JOY IN LIFE WITHOUT PORTED ROTARY”

[@zeonicseafood4819]

Buddhask🐐

[@Dancerman007]

That's what's up holy shitttttt!!!!! What a G

[@timothy-sr1gh]

And he was right

[@swampyfox8688]

Erich telling it like it is. Craftsmanship = Reliability. Period. Thanks for showing folks the right way AND the wrong way. “If something’s worth doing, it’s worth doing right”.

[@IHWKR]

Craftsmanship can mean little when things are also abused.

[@jakerubino3233]

I had a bridge ported RX4 based 13B with 48mm Weber in my ‘82 RX7 many years back that I daily drove for many years without skipping a beat. It had been running strong for about 75-80 thousand kms before I gave it a good send off so my new 13B turbo engine could take its place. The send of was easily one of the longest smokiest hardcore burnouts I’ve done. Not sure how many kms were left in it after that but it was still kicking. It’s still on a stand in my garage untouched since then. Built well and looked after by people that understand rotaries, they can defy most general concepts that less experienced people have.

[@jort88]

So...i've been into cars since I was a small child. (Grew up at the race track with my father). I've been a German car guy the past 6 years, oil leaks, coolant leaks, turbos all of it. I currenty have a FBO Mk7 GTI on E85 with a Is38+ turbo (400ish). A 8v RS3 FBO on corn as well (~high 5, low 600s). I came across your channel 3 months ago and i've watched just about all your videos, and have really interested me with the spinning dorito. Well, this past Monday I bought me a project S1 MT Rx-8! Kinda runs, but it's a solid chassis and transmission shifts great. Planning to rebuild and street port it myself. And all this has happened because of your videos. Powerful stuff man, keeps the videos coming! Also signed up on your Pateron!

[@orlandonostagiafever1964]

I had a street ported 12A in my 73 Rx2 had it as a dally driver for 5 year's never had problems.

[@does_not_matter_91]

I really like and appreciate the time and effort put into those videos. Tons of knowladge here. I would love to see more videos on the Renesis though, if that's something your interested in too. There's tons of RX-8s out there, being crushed because of the costs and people being scared to do those engines on their own :) A proper series of videos about it might help. Cheers!

[@RADPotential]

Rx8 engine build starts this weekend. Might be a few weeks before a video hits the channel.

[@btownballer27]

​@@RADPotential RX8 dude here cannot wait for this. Picked up my Black on Black 05 before the snow flew up here. Needs improvements but runs great atm. Came for the 8, stayed for the rest. Love the content brother.

[@lun7n]

@@RADPotential make sure its not a reman engine.

[@jerryglennie5375]

@@RADPotential curiosity, but is the renesis going to be a 4 port or 6? I ask purely because I would like more information on making a 6 port breathe more efficiently in the use of added power gains vs cooling effectiveness. (05 shinka here)

[@Ori3ntal3Xpr3ss]

Going 3 years spirited driving my large Bridgeport 13B 6 port turbo. You have a quality builder you’ll have a reliable engine.

[@Sparkling.Fresca]

I think high rpm balancing should be performed anytime you want a strong engine, especially if porting is done, and balancing should help maintain reliability with conservative porting. The rotors truly do wobble at speed, this is something that Daryl Drummond has pushed for years at Star Mazda's racing program. In fact this is one of the major flaws of the RX8's rotors, they are not very well balanced from the factory as they could be. This is fine if you keep max rpm to 8500 (gauge is 500rpm off), but running it at sustained high rpm's will see reliability issues. I say you do you a video on this subject, it is definitely worth talking about.

[@RADPotential]

Yes sir!! I have an idea in the future for some comparisons with a blueprinted 12a vs a stock rotating assembly. But I need to figure out how to "measure" the harmonics

[@tomjones7853]

You should alway go to a machine shop and have your rotaing assembly balanced . Period

[@YAHYEL-ANUNNAKI]

Have you figured it out yet?

[@outinthebackyard7579]

Good video. One theory that I have from my years of working as a mazda technician is that the stock rotary engines need to see lots of rpm. Our customers that drove mrs daisy would usually be on their third engine by the time they were out of warranty. The customers that drove their rotary hard and ran them all the way out to 9k would usually never need a engine replacement within the warranty term of 100,000 miles. The theory is that the hard driving helps keep the carbon out of the seals so they don’t get the sticky side seal that usually causes them to drop compression.

[@VinsUplifting]

I always redline at least once anytime i take the car for a ride. Many people seem to think this is a good thing to do..

[@CHIBA280CRV]

Awesome, I will check out the rest of your videos. I have a 13b sitting in my garage . . It came off a 1989 rx-7 convertible …. I know nothing about the engine Other than what I was told, and that is that it was ported and it only had 4000 miles on the rebuild..has a sweet looking clutch as well..It was running when I pulled it out the vehicle.. it sounded and ran great..! It would be awesome to install a carb. On it like a Holley 4 barrel..unfortunately I got rid of the transmission, but kept the stainless exhaust , it had new wheels and tires so I installed them on my CR-Z…hopefully one day I can make a project out of it.. I love the sounds of the rotary engines..👍🏼👍🏼👍🏼👍🏼👍🏼 thanks

[@Yukanhayt-Mhenow]

Thank you for finally somebody tells the truth that a lot of rotary builders are shit and most rotary drivers are harsh, creating a bad name for reliability on Mazda's product.

[@ScottJ175]

Also...good to see you back and glad nothing bad was keeping you away. I've been fighting being bummed because I have messed up the transmission tailshaft seal on my RX-8 twice now. I have bought the latest revision of the seal from Mazda and am waiting for the actual special service tool for driving it to arrive since my improvised drivers (Jeep axle nut socket the first time and PVC pipe the second) combined with limited workspace seem to be causing me issues.

[@tomjones7853]

How do you mess that up? I have smacked them in with hammers and sockets

[@melaboul5020]

Thanks to your videos I ended up refreshing my rx8 engine

[@xaebion]

You’ve been the best rotary channel on KZbin for a while now. Thank you for all your videos. Keep it up!

[@craigfleming-dc7fw]

It was a well known fact in the 1990s,if you Bridgeport a Rotary or even wilder, the engine rebuild would last only 10,000 kilometers or only 6k miles!!! It's for a racing car, not street application

[@davidparker9676]

I worked with a guy that would change rotary engines about every week. He refused to properly build any of them for the turbo he had on it. I always found these interesting but didn't have good experiences with them, every one became a smoke machine too quickly. It's really cool to see a channel with detailed help for the Wankels.

[@aydankraemer377]

Hey man, been watching your vids for almost a year now, been getting the motor out of my 8 last weekend and should have it out this coming this weekend, just wanted to say your videos along with kmr and a few of the other dorito guys are a huge help and honestly the reason for me getting into them, can’t wait to see where they take me… planning on street porting this one na and getting ready to hybrid turbo setup the other rx8 I’ve got now later on this year hopefully, they are so much fun to drive and hear but man gotta have some deep pockets for these rebuild and parts 😂👌 keep ‘em coming man your making me want to start a yt channel for all the car stuff.

[@TexasVexes]

Thank you for this video. I believe that porting/engine build is a small but very critical piece of the puzzle. All the supporting mods that go along with it (e.x. Waist gate, engine management, injectors, Quality turbo etc.) All play a role in engine life.

[@dukedub]

My car made 300 wheels on stock ports. It’s honestly more than the fb chassis can really handle, I had a good laugh when you said you lift at 80mph because the car shakes. So true lol wish I still had some local rotary friends to play with

[@stevinsjeune6471]

Thank you for the knowledge much appreciated... Working on doing a Miata NC Swap with 13B T2.. I will be purchase my engine from REC. Once again thanks for all your videos.

[@MrMeoow91]

Just had my S4 13B NA engine rebuilt. Many people were dissapointed at me not going for bridge port or any porting at all for the beautiful rotary noise. Without upgrade to Intake, Fuel injector, Exhaust and Aftermarket ECU for tuning, no matter how big the port is, you will not garner all the power from the porting. That would also require even more money and it is not guarantee to run right. I just wanted a reliable and long lasting engine.

[@RS-sv3bl]

I watch every video (Sep 24). Great content dude - great show. Rotaries for life! Keep it up

[@benbradshaw29]

I'm starting to wonder if a shitty port job is what killed my old engine. Some of the other work on the car was really rough. If that guy did the engine too... let's just say I'm happy to be starting from stock

[@RADPotential]

Yep! I have seen some pretty poor port work. its for sure not helping anything

[@Soundpost-f2l]

​@@RADPotential about cnc porting....I'm assuming there's a drawing or file out there for those templates, right? Do you think it would be effective for me to use the dowel holes as locators on a cnc machine and then just run a pocket milling program based on the template? I trust my abilities to deburr or make fine adjustments to a port, I don't trust myself to actually hog all the material out by hand.

[@trevc4021]

Hi Erich. Greetings from New Zealand! I'm putting a 13BT from a series 4 RX7 into a Ford105e Anglia (Yep, A Harry Potter flying car) Thinking of a half bridge and doing some research. Just found your channel and have subscribed. Just wanted to say it was your quality explanation that got the subscription button clicked. I'm looking forward to seeing more of your content.

[@alallan6285]

Hey, Kiwi here too. Keen to see how the Angle box went, and goes!

[@markkennard861]

Us kiwis and our rotary's.. hard case..

[@benrobertson7855]

Yep.gotta be a rota if your a kiwi… lovin my 13b full bridge. regards from the far far north.

[@chuckrankin370]

Nothing like attention to your detail. I'm a 20 year diesel mechanic that just got my son , who wants to get into the mechanic world , a 1988 SE 13b. Being in SC , not the first patch of rust. Somewhat have knowledge of the origin of the car, and was owned by a midlife crises guy that took impeccable care of the car. Following your knowledge , we both are looking forward to have a Tail of the Dragon car ....

[@peterga3658]

cant wait for more videos mate .. Hi from Greece

[@donaldglaser7686]

Worked at a RX7 place in the 90s that had two bridgeport GT3 cars. Beat the hell out of them season after season. I delivered pizza in a P-port. Build them right. Treat them well.

[@LordCakeskull]

I really wish there was someone offering CNC port work here in the UK, I have an Rx8 engine which I don't trust myself to port by hand.

[@kareemjackson4336]

New subscriber and grabbing my notepad for all my needs on my new rotary journey

[@BroomysGarage]

I tell people and customers all the time, screw the Bridgeport option for a street car. They never listen though 😂 and then most totally regret it.

[@el_peluca_]

Thank you for sharing your experiences! Greetings from Chile

[@Tysmelo6]

Had a PFS full bridge in fd and she went lean. Ran fine till it didn't. Now has big street ports. Driveability huge

[@ADudesRotary]

For those like myself who do not have a home cnc would you recommend using a drill press to do the porting. Thanks for another great video.

[@btownballer27]

Great recommendation!

[@RADPotential]

You could drill press the holes for the bridge yes. But honestly the best way is to get junk irons and practice

[@mohammadalabdulrazzaq]

I think ur 1000% right how the irons ported effects how reliable the engine is 👌

[@Taliyon]

Solid channel. I'm sold.

[@barrydavid8794]

Glad I’m Australian, we have the best rotary builders in the world. Pac Performance from Sydney builds reliable 13B Bridgeport turbo motors, that will run sub 10sec 1/4 miles. Just remember that rotary engines try to twist themselves apart, they need to to studded and dowelled to stop that from happening.

[@scottswisher9456]

I had a fresh rebuild on my 8, tuned, stock ports, no cat, I ran the shit out of it, taking off from a dead stop at 3k rpms, running down the road staying above 3k at all Times, there was times when racing with my buddies I stayed about 5000 because that's where all its torque and power really is, it's where it's fun to drive...well that motor lasted all of 1yr and maybe 3 months...lol...I changed my oil 2 times a month, only used conventional oil. I changed plugs every 3 months....

[@lezzbmm]

just discovered yr channel and love yr shit been a "theoretical" rotary nerd since i was a teenager in the 00s this is just so cool thx 4 sharing !

[@lezzbmm]

i have a na miata shell and a s4 13b and some swap mounting hardware sitting in my shed waiting for me to find the time and energy to rebuild the motor and swap it in yr videos make me think i can actually do it one of these days lmao !

[@SuperSick]

I’m so grateful I only street ported mine 😅 but if I were to back I would’ve left it stock tbh

[@OmarGarciaElDeLa_O]

Thanks for the info bro. Happy New Year... 🇵🇷

[@onecookieboy]

Nice video, the take out is that you are probably better off paying someone else to port your engine for you but I guess that part of the problem with rotaries is that the people who want to modify them are the same people who often overestimate their ability and don't take their time to do a good job, I am guilty of that myself, me and my friends, back in the day, messing with things we didn't quite understand and all trying to be 'the man'.

[@steveb9270]

The 12a bridge port I had cracked across the bridge and destroyed the seals after a while only a small crack to but enough to chew out the seals

[@Soundpost-f2l]

Can you weld it back and then deck it down on a mill? Or a lathe if you can get it in the chuck.

[@kieranstephenson3187]

Great video man! I'm looking forward to continually learning more and more about these engines, and this channel is a great place to do so. Keep up the awesome content, looking forward to more!

[@everzamora9031]

From owning rotaries for a while. I can say xtreme rotaries streetport and small half bridgeys are the way to go for power downbottom to up high. Very rarely have i heard or driven a rotary with full bridgeys and pports that actually sounded good but performed spectacular. For the most part these cars i speak off where drag,track specific. Other than that not impressed in street/track vehicles. The sound is loud and obnoxious and power uptop. Love my streetports and small half bridgeys for power and sound.

[@ScottJ175]

Makes me think of guns don't kill people. So ports don't kill engines. In both cases it's the user of the tool that should get the blame. Personally I have no interest in porting because it moves your power band up the rev range and as Nate Rist points out midrange is where it's at on the street.

[@ottolohr]

Great overview

[@bayareapeezy]

I have a question if you just drill the holes with gaps into the next hole and left it that way..... how would that sound and cause the engine to operate?

[@RedLine_Renesis]

I've always owned and loved rotaries. Although I understand people are scavenging for extra power, I can't stand the brap noise. I prefer the smooth idle the stock porting provide.

[@VinsUplifting]

Same here, nothing beats a smooth idle for me..

[@Dug6666666]

Thanks for demystifying rotary porting. I wish I had this sort of resource back in the day before even owning a computer, when I was messing with rotaries. Twin 2" pipes all the way to the back, machining out 12A carb venturi sleeves 1mm a side on the diameter, and a rejet was as far as I got. Made it a much better car than the back firing, inefficient, pollution control fitted, Japanese import series1 RX7 I started with though.

[@vinnukona8956]

could I make my bridge port not as wide to leave more room for the water seals and a wider bridge?

[@guyb6665]

but is street porting an rx8 my2008 series 2 going to affect reliability much? Engine compression is way down so needs pulling apart anyways

[@Devili5h]

Hi thanks for the great content! Still the best! Would you mind doing a comprehensive video on cleaning rotors and housings for renesis or just in general. the best and most cost effective way to super clean internal parts before stack em together.

[@RADPotential]

I'll make sure to touch on that in the next engine build video. It will be soon

[@Devili5h]

@@RADPotential thank you

[@LOKISX]

good informative vid bro cheers.

[@AMADOFUENTESJR]

What’s the best way to change oil pan gasket? 12A 85’ rx7

[@i_eat_glue_]

Out of curiosity are there shops that do it or someone I can pay because I don't fully trust myself?

[@VictorMPR]

Super awesome info! Also, at 4:30… that iron you are touching has the same type of “damage” that my RX-8 irons do (rotors sat in a puddle of coolant for some time due to previous owner not knowing what was wrong with the car). I was assuming they were done, but is that something that could be remedied by machining… in your opinion?

[@RADPotential]

I have never had a set of irons lapped or cleaned up. Most I do is clean them up with a scotch brite pad, but I wouldn't steer away from using that particular one in the video as is. its just some staining really. no step wear

[@VictorMPR]

Thank you!

[@samuelfowler2157]

Help me. Ive always heard to run the hell out of rotary engines and them rev them to redline when turning them off... but this video seems to contradict that. Someone explain

[@urielcarranza8829]

What about a full peripheral port engine

[@christophermolden9151]

Hey can u send me something on how to build the rotary and where to get the template on porting

[@dakotamedlin48]

Wondering what the best series of 12a is? Or are they all the same built engine?

[@jcramirez37]

Is confiable install 2 piece Apex Seal 3mm in a 13B Bridgeport ?

[@LuisRomero-se9ed]

Is it worth porting a 12A automatic?

[@rideswithhoover9789]

What’s the difference between a bridge port or an extend port

[@Lordlindef]

There is paper whit exurqte messurments ??? Was shire of that i sems to remember

[@cemturyan2653]

Awesome video! I really like your content. I thought a Bridgeport would eventually damage the corner seals. What do you think of a semi pp?

[@RADPotential]

Honestly a semi PP or just PP in general would be wah less risk

[@carlosslugo]

Do you rebuild rotaries for clients?

[@biggj6187]

How long can the bridge port turbo last more then 5k miles ?

[@Phanton-Racing]

Do you have engines for sale? I'm looking for a 12A with carriage and bridge for my 1983 RX7, I don't want to make it 13B I want to leave it 12A.

[@Lostbomber]

Needless to say I think I need to port my 13b-rew.

[@aaronpitts2762]

Legends in NZ make reliable braaps

[@robertwhattam6721]

Which video of yours shows your engine build box that you put the apex seals, corner seals and so on in. So you know what goes with each rotor.

[@RADPotential]

That would be a tough one. I dont exactly remember. Probabaly my comprehensive rebuild video. If I had to guess.

[@camjones1106]

Do a graph , rpm versus reliability , surely rpm creates the extra stress therefore less reliability

[@pilotohernandez1569]

I'm planning on moving to Crossville TN and I'm having a 85 FB and I'm wondering about cars inspection do it need to be inspected?

[@WhysafraidofCause]

Always good to get a compression test

[@udaaz]

Very nice 👍

[@benjamindiaz46]

Where you located I would like for you to work in my 12 a. Engine

[@Nandele_76]

I have a 83 12a engine that was street ported before I had it opened to do a bridge port, my question is since I am running a 48ida weber on it what jetting you recommend for it, car is running sounds Amazing but rpms fall short at around 6500, I'm running -6a feul lines from tank to weber. Any recommendations are really appreciated, by the way luv your channel and thanks for all your knowledge...

[@RADPotential]

If you hop back on the channel a bit, I go thru tuning my Weber 50DCO for a full bridge 12a. I would look at those settings and that might get you close. I was running 43mm choke tubes. my guess is that you probably have 38mm chokes in that 48ida

[@TylerGamer765]

haha ur dog reminds me of my lil pit

[@stevensmi1167]

Erich Hello can you tell me if 13B na Bridgeport porting is the same as turbocharged Bridgeport porting? I have searched but I can’t find anything!

[@RADPotential]

Unlike the piston world, I have never really seen much mainstream Info on ports being done specifically for boosted applications. I'd bet that people have some sort of shape or size that works better for a turbo application than NA. Maybe less overlap. More duration, open the exhaust port sooner? Just thinking out loud haha

[@mmag9159]

odd question. do you chamfer your housings when running a bridge? i've seen people run them without and it seems just fine. but like what kind of benefit can you see from that?

[@RADPotential]

I have seen it done often. Typically people pull the bridge back towards the coolant seal as you can only come forward so far for the corner seal to ride on something of substance. I'd say if you trying to squeeze every mm of power out of it. That's the benefit. Bigger ports mean more power. But I couldn't tell you if it's worth 1% or 10% more powe

[@bstewart3927]

Do you have choke cable for 85 rx7 12a

[@grumpyoldman6632]

By moving torque further up the rev range, it makes the driver rev the engine more. Hence it will wear out earlier. Meh, you pay for performance.

[@KreatorOfDeath1985]

Is the 12a THAT much worse than a 13b? And will an NA rotary run boost on e85 the same way a high comp piston engine could?

[@RADPotential]

12a stock ports are tiny yes, but everything has its benefits IMO. With regard to boost, highest compression rotary engine is 10:1. Which is really not that much compression for a piston engine.

[@l8tapex]

Devcon water jacket monsta bridge.... lol. Mr. Downing/Rabbit

[@fc3sboy1]

Also the side seal breaks on high rpm mis shifts and bad down shift timing . Not 100% a port design and that crappy 3/4 bridge port still isn't the issue poor tuning and bad driving breaks engines

[@TheJalliam]

Could you run a street port on a n/a factory ecu from an 88 rx7??

[@dukedub]

Ports are for ppl who plan to add engine management and supporting mods. If you’re willing to upgrade it you need to go all the way. Or just leave it stock and enjoy it.

[@mikeraghu3480]

Where are you located?

[@fc3sboy1]

111hp ?????? That is about 75-90 hp light on a good 12a street port . A good EP 12a with 40mm chokes in the down drafts nets 175-190 whp on 87 octain with a street port only

[@M1R00TJ3]

nice vid

[@jackthayer904]

Do you have any experience porting the 6 port rx8 engines?

[@RADPotential]

I haven't done an rx8 6 port. But the older FC 6 ports yes

[@btownballer27]

I've heard porting the MSP isn't beneficial. However that's all I have heard. Mainly from what I understand is because they are NA and that limits the overall point. Unless it's boosted (many don't last on boost too long). It's a lot of work and money for the sound if thats all you are going for.

[@mrsquirrel8079]

Semi pp???

[@boatymcboatface666]

Bridge Port? Pfff, it's all about the Peripheral Port! 🤣

[@brentmcmillan4347]

Crappy machine work will cause any engine to be unreliable. Also adding more rpm.

[@joshuadavis862]

Enjoyed the vid man I just pray that everyone who hasn’t accepted Lord Jesus as they’re savior and repents today. Believe on him and keep his commandments and be saved.

[@wheressteve]

What kind of person would want no braps ???

[@uselessoutdoorsman2826]

Another great video, appreciate the information!

[@carloszgsx2896]

I am from puerto rico 🇵🇷🇵🇷 rotary island

[@BobNew-n5i]

Go Bridge or go home 😁

[@33naki]

You are Owen Wilson's son

[@RADPotential]

"wow"

[@Ammotive28]

But, but brap…

[@garageworm17]

From white guy to white guy this is a Hispanic world you want nothing apart of they mske that shit go fast and that all we can sak for let go r🇵🇷🇵🇷🇵🇷