How to mod a 13b
#26
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Originally Posted by 3times
heres a start. Headers/exuast/intake/efan/street port/. that should put u around 175 (Pure guess can anyone verify horsepower for these modes?)
Like, Injectors, Fuel pump, SAFC II, or what else?
#27
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The SE already has 680cc injectors,what it lacks is 4 staged injectors like the later models and a decent pump.Switching to a later year EFI setup will give you more flexibility and better breathing manifolds...but youll lose the SE's super low torque curve,the later years peak around 3000-4000 RPMS.
Save the money on the SAFC.Basically a piece of sh*t with a fancy screen,its only a viable option for speed density fuel injection,like Honda.On metered air systems is just a pain in the *** that will argue with the factory EFI components.And its not needed since the factory EFI can safely meter fuel anywhere within the AFM's range.The only useful thing a SAFC can do is trim down idle mixture to make up for too large injectors(basically a band-aid fix)
Work on you ignition and exhaust systems.Both are EXTREMELY responsive to upgrades.A rotary needs all the ignition help it can get,and the stock exhaust is a far cry from effecient.
MSD6A on leading
Direct fire conversion
3 Blaster(or other) coils
A little timing advance
Good wires and new plugs
Headers/presilencer and muffler.
These mods can net you 25-30 HP on a 12A,which is a 25/30% gain over stock!!
On an SE it will be even more with the bigger 13B engine and the EFI will automatically adjust for the increased airflow the engine will experience.
Save the money on the SAFC.Basically a piece of sh*t with a fancy screen,its only a viable option for speed density fuel injection,like Honda.On metered air systems is just a pain in the *** that will argue with the factory EFI components.And its not needed since the factory EFI can safely meter fuel anywhere within the AFM's range.The only useful thing a SAFC can do is trim down idle mixture to make up for too large injectors(basically a band-aid fix)
Work on you ignition and exhaust systems.Both are EXTREMELY responsive to upgrades.A rotary needs all the ignition help it can get,and the stock exhaust is a far cry from effecient.
MSD6A on leading
Direct fire conversion
3 Blaster(or other) coils
A little timing advance
Good wires and new plugs
Headers/presilencer and muffler.
These mods can net you 25-30 HP on a 12A,which is a 25/30% gain over stock!!
On an SE it will be even more with the bigger 13B engine and the EFI will automatically adjust for the increased airflow the engine will experience.
#30
Unless your a drug dealer at 16 aint no way your dropping 15K unless its your parents car or you are a really friggin rich kid. BTW I think we would all be curious to hear what you did to crank 500 HP out of a camaro not that I doubt a camaro can do it. But I dont know a 16 y/o kid anywhere with the experience to handle 500 HP out of anything. sorry if I sound like a hater but J/W......
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Originally Posted by RX(ZONE)
And where abouts would that land me on the HP chart with a street port with no emmisions?
And thanks by the way, you've been a big help.
And thanks by the way, you've been a big help.
Not 100% sure for the power gains as Ive never built any 6 port n/a engines.Id say somewhere around 170 crank HP,up from 135,maybe more.....The S5 13B was up to 160HP factory with only minor alterations from the SE's original guise.
The 6 ports dont respond as well to porting,but theres still a little power to be had from a port cleanup and a little more duration.
Also,I forgot...a light flywheel make a very good upgrade for any rotary.While it doesnt add any horsepower,it does allow the engine to rev up MUCH quicker in the lower gears.Most rotaries have very heavy flywheels to help make up for their torque defeciancies.But this also keeps them from accelerating briskly as the engine has to apply more power to get the heavy flywheel turing.A light flywheel will give you quicker rev up in the first 3 gears and dirtbike-like throttle response.The downside is that the engine will be easier to stall when letting the clutch out,but you get used to it very quickly.After a few days,youll be comfortable with the clutching needs and the mod will be transparant.
Got light steel for a nice gain and easier clutching.....or go super light aluminum for all out performance and a little less driveability.
Last edited by steve84GS TII; 11-07-05 at 11:42 PM.
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Originally Posted by steve84GS TII
My pleasure,
Not 100% sure for the power gains as Ive never built any 6 port n/a engines.Id say somewhere around 170 crank HP,up from 135,maybe more.....The S5 13B was up to 160HP factory with only minor alterations from the SE's original guise.
The 6 ports dont respond as well to porting,but theres still a little power to be had from a port cleanup and a little more duration.
Also,I forgot...a light flywheel make a very good upgrade for any rotary.While it doesnt add any horsepower,it does allow the engine to rev up MUCH quicker in the lower gears.Most rotaries have very heavy flywheels to help make up for their torque defeciancies.But this also keeps them from accelerating briskly as the engine has to apply more power to get the heavy flywheel turing.A light flywheel will give you quicker rev up in the first 3 gears and dirtbike-like throttle response.The downside is that the engine will be easier to stall when letting the clutch out,but you get used to it very quickly.After a few days,youll be comfortable with the clutching needs and the mod will be transparant.
Got light steel for a nice gain and easier clutching.....or go super light aluminum for all out performance and a little less driveability.
Not 100% sure for the power gains as Ive never built any 6 port n/a engines.Id say somewhere around 170 crank HP,up from 135,maybe more.....The S5 13B was up to 160HP factory with only minor alterations from the SE's original guise.
The 6 ports dont respond as well to porting,but theres still a little power to be had from a port cleanup and a little more duration.
Also,I forgot...a light flywheel make a very good upgrade for any rotary.While it doesnt add any horsepower,it does allow the engine to rev up MUCH quicker in the lower gears.Most rotaries have very heavy flywheels to help make up for their torque defeciancies.But this also keeps them from accelerating briskly as the engine has to apply more power to get the heavy flywheel turing.A light flywheel will give you quicker rev up in the first 3 gears and dirtbike-like throttle response.The downside is that the engine will be easier to stall when letting the clutch out,but you get used to it very quickly.After a few days,youll be comfortable with the clutching needs and the mod will be transparant.
Got light steel for a nice gain and easier clutching.....or go super light aluminum for all out performance and a little less driveability.
I was planning to do a lot of the things you have said, just wanted to know some ideas to suck more power out of it. Im building my -se for handling, and quickness, rather than brute force, and speed.
#35
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Converts the engine to 4 port.
That will require more work as going 4 port will basically redefine the engine.New intake manifolds are needed,usually TII if you wanna stay EFI.
The extra breathing of the 5-6 aux ports will be gone,but youll gain more potential to port it out to make power.
The aux ports are Mazda's version of VTEC,providing more topend power,but turning off at low speeds to maintain down low torque.Thats why the 6 port's primary intake ports are so small,to keep the bottom end power healthy.Then, when the engine gets revved up and needs more air,the secondaries and then the auxilliaries open up.Its all designed to work with the dynamic tuning (the shape) of the strange looking intake manifold.Thats how the non turbo 13B is able to make nearly as much peak torque as it does peak horsepower.This is usually only the case with turbo engines.
The turbo 13B has only 4 intake ports.Reason is,it doesnt need the complicated dynamic intake tuning since the turbocharger will force feed the engine its air,without any need for more ports or complex intake tunnels.
The choice to use 12A irons should be dictated by your final goal for the engine.It requires a full rebuild to change the iron plates,so if your not planning on going turbo,theres little reason to convert to 4 port.
That will require more work as going 4 port will basically redefine the engine.New intake manifolds are needed,usually TII if you wanna stay EFI.
The extra breathing of the 5-6 aux ports will be gone,but youll gain more potential to port it out to make power.
The aux ports are Mazda's version of VTEC,providing more topend power,but turning off at low speeds to maintain down low torque.Thats why the 6 port's primary intake ports are so small,to keep the bottom end power healthy.Then, when the engine gets revved up and needs more air,the secondaries and then the auxilliaries open up.Its all designed to work with the dynamic tuning (the shape) of the strange looking intake manifold.Thats how the non turbo 13B is able to make nearly as much peak torque as it does peak horsepower.This is usually only the case with turbo engines.
The turbo 13B has only 4 intake ports.Reason is,it doesnt need the complicated dynamic intake tuning since the turbocharger will force feed the engine its air,without any need for more ports or complex intake tunnels.
The choice to use 12A irons should be dictated by your final goal for the engine.It requires a full rebuild to change the iron plates,so if your not planning on going turbo,theres little reason to convert to 4 port.
#36
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Ok, thanks a lot.
One last question. Emmisions removal, How helpful, and how hard is it? When i bought my car it didnt have the air pump, so I already have gotten rid of that, but what else?
One last question. Emmisions removal, How helpful, and how hard is it? When i bought my car it didnt have the air pump, so I already have gotten rid of that, but what else?
#37
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If you've ditched or dont have the airpump,youll need to remove or gut the cats or they will self destruct very soon and kill your power by clogging the exhaust system(it can even kill the engine if the backpressure gets too high).
The airpump system and cats constitute the bulk of the smog control gear,so if they go,you might as well pitch it all.Some of the vacuum hoses and solenoids on the engine are needed for proper EFI function however,so dont toss it all.Get a factory service manual if you wanna know everything there is to know about the SE's engine.Its a great tool.
The actual power gains from removing the smog gear is minimal.The smog pump only draws a horsepower or 2 at the most.The biggest hinderance to power from the smog gear is the old style cats.Replacing them with a modern 3 way cat will keep you clean (no more burning eyes) and probably be a horsepower INCREASE over the bone stock 80's engine.The stock 80's cats SUCK big time and are bulky and heavy.The only real advantage to removing all the smog gear is that your engine will look clean and simple and might be a little quieter without the smogpump spinning.
You can make good power and stay clean.Most people opt to remove the smog gear out of spite,fear or ignorance.I make about 300HP with my S5 TII setup and its totally CA smog legal.Smog pump,cat,all the hoses and everything is intact and working...
The airpump system and cats constitute the bulk of the smog control gear,so if they go,you might as well pitch it all.Some of the vacuum hoses and solenoids on the engine are needed for proper EFI function however,so dont toss it all.Get a factory service manual if you wanna know everything there is to know about the SE's engine.Its a great tool.
The actual power gains from removing the smog gear is minimal.The smog pump only draws a horsepower or 2 at the most.The biggest hinderance to power from the smog gear is the old style cats.Replacing them with a modern 3 way cat will keep you clean (no more burning eyes) and probably be a horsepower INCREASE over the bone stock 80's engine.The stock 80's cats SUCK big time and are bulky and heavy.The only real advantage to removing all the smog gear is that your engine will look clean and simple and might be a little quieter without the smogpump spinning.
You can make good power and stay clean.Most people opt to remove the smog gear out of spite,fear or ignorance.I make about 300HP with my S5 TII setup and its totally CA smog legal.Smog pump,cat,all the hoses and everything is intact and working...
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Originally Posted by steve84GS TII
A 250 crank HP 13B is not very hard to build and might cost 1800-2000 bucks depending on how you shop.Itll make an otherwise stock FB into a formidable street machine and wont require a big rearend,brakes,suspension,chassis mods,ect.
#39
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I was reffering to a TII engine swap,as opposed to building up an SE engine.
Right off the bat,the thread was talking about turbo engines since 400RWHP was the initial goal.I wouldnt waste my time trying to build a turbo SE engine when TII engines are so prolific.
Stock is 180-200HP depending on year.Intake,exhaust can easily get you 50HP with about 10psi.
1800-2000 bucks for the engine purchase and mods,assuming you install it yourself,as I did.
Right off the bat,the thread was talking about turbo engines since 400RWHP was the initial goal.I wouldnt waste my time trying to build a turbo SE engine when TII engines are so prolific.
Stock is 180-200HP depending on year.Intake,exhaust can easily get you 50HP with about 10psi.
1800-2000 bucks for the engine purchase and mods,assuming you install it yourself,as I did.
Last edited by steve84GS TII; 11-08-05 at 05:28 PM.
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Originally Posted by steve84GS TII
If you've ditched or dont have the airpump,youll need to remove or gut the cats or they will self destruct very soon and kill your power by clogging the exhaust system(it can even kill the engine if the backpressure gets too high).
The airpump system and cats constitute the bulk of the smog control gear,so if they go,you might as well pitch it all.Some of the vacuum hoses and solenoids on the engine are needed for proper EFI function however,so dont toss it all.Get a factory service manual if you wanna know everything there is to know about the SE's engine.Its a great tool.
The actual power gains from removing the smog gear is minimal.The smog pump only draws a horsepower or 2 at the most.The biggest hinderance to power from the smog gear is the old style cats.Replacing them with a modern 3 way cat will keep you clean (no more burning eyes) and probably be a horsepower INCREASE over the bone stock 80's engine.The stock 80's cats SUCK big time and are bulky and heavy.The only real advantage to removing all the smog gear is that your engine will look clean and simple and might be a little quieter without the smogpump spinning.
You can make good power and stay clean.Most people opt to remove the smog gear out of spite,fear or ignorance.I make about 300HP with my S5 TII setup and its totally CA smog legal.Smog pump,cat,all the hoses and everything is intact and working...
The airpump system and cats constitute the bulk of the smog control gear,so if they go,you might as well pitch it all.Some of the vacuum hoses and solenoids on the engine are needed for proper EFI function however,so dont toss it all.Get a factory service manual if you wanna know everything there is to know about the SE's engine.Its a great tool.
The actual power gains from removing the smog gear is minimal.The smog pump only draws a horsepower or 2 at the most.The biggest hinderance to power from the smog gear is the old style cats.Replacing them with a modern 3 way cat will keep you clean (no more burning eyes) and probably be a horsepower INCREASE over the bone stock 80's engine.The stock 80's cats SUCK big time and are bulky and heavy.The only real advantage to removing all the smog gear is that your engine will look clean and simple and might be a little quieter without the smogpump spinning.
You can make good power and stay clean.Most people opt to remove the smog gear out of spite,fear or ignorance.I make about 300HP with my S5 TII setup and its totally CA smog legal.Smog pump,cat,all the hoses and everything is intact and working...
One more question lol. Racing Beat exauhst, which one do I want? (price isnt an issue) and does it still create backpressure to open my 5th and 6th ports?
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http://www.mazdatrix.com/r-exh-85.htm
http://www.mazdatrix.com/getprice.as...m=16-MZTX-4230
This is setup for EFI,6 port actuation and it uses the streetport muffler.....price is no problem,right?!...heh,heh.
http://www.mazdatrix.com/getprice.as...m=16-MZTX-4230
This is setup for EFI,6 port actuation and it uses the streetport muffler.....price is no problem,right?!...heh,heh.
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Originally Posted by steve84GS TII
#43
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Why wire open the ports?
That exhaust system is designed to operate the ports at 3500rpm by using a pressure signal near the front exhaust port.The secondary injectors wont be spraying any fuel until 3800 RPMS anyway,so having the aux ports open full time will serve no purpose............sorry didnt notice the carb comment at the bottom.No idea about HP,but I seriously doubt itll be 300 crank HP(250RWHP)
The aux ports extra volume and duration is not needed until higher in the revs.If you wire them open,youll just bog the engine at lower/midrange revs,every time you floor it.Its the same effect as running mechanical secondaries on a carb.You might demand full throttle right now,but if the engine doesnt have enough rpms and port flow to get things moving,the power wont be there.
Vacuum secondaries and backpressure operated intake ports both serve the function of allowing port velocity to increase as quickly as possible,by keeping the intake tract smaller.Then,when the ports are maxxed out,the extra ports will open and allow even more breathing.Opening them sooner or permanently will just induce more lowend lag,just like super big intake porting does on bridge and PP engines.
That exhaust system is designed to operate the ports at 3500rpm by using a pressure signal near the front exhaust port.The secondary injectors wont be spraying any fuel until 3800 RPMS anyway,so having the aux ports open full time will serve no purpose............sorry didnt notice the carb comment at the bottom.No idea about HP,but I seriously doubt itll be 300 crank HP(250RWHP)
The aux ports extra volume and duration is not needed until higher in the revs.If you wire them open,youll just bog the engine at lower/midrange revs,every time you floor it.Its the same effect as running mechanical secondaries on a carb.You might demand full throttle right now,but if the engine doesnt have enough rpms and port flow to get things moving,the power wont be there.
Vacuum secondaries and backpressure operated intake ports both serve the function of allowing port velocity to increase as quickly as possible,by keeping the intake tract smaller.Then,when the ports are maxxed out,the extra ports will open and allow even more breathing.Opening them sooner or permanently will just induce more lowend lag,just like super big intake porting does on bridge and PP engines.
Last edited by steve84GS TII; 11-08-05 at 09:45 PM.
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Originally Posted by steve84GS TII
http://www.mazdatrix.com/r-exh-85.htm
http://www.mazdatrix.com/getprice.as...m=16-MZTX-4230
This is setup for EFI,6 port actuation and it uses the streetport muffler.....price is no problem,right?!...heh,heh.
http://www.mazdatrix.com/getprice.as...m=16-MZTX-4230
This is setup for EFI,6 port actuation and it uses the streetport muffler.....price is no problem,right?!...heh,heh.
And so does the RB system not acctuate the 5th/6th ports, or am i blowing smoke out of my rear end?
#45
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I never had 15K in a lump sum. I did a complete restoration and invested 15K over a period of 8 months. I just found this RX7 lying in a field, went out there got it running last week and now I wanna cheaply mod it up a bit to have some fun in my free car. And thanks for all your advice guys, it has been dually noted.
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Originally Posted by steve84GS TII
Why wire open the ports?
That exhaust system is designed to operate the ports at 3500rpm by using a pressure signal near the front exhaust port.The secondary injectors wont be spraying any fuel until 3800 RPMS anyway,so having the aux ports open full time will serve no purpose............sorry didnt notice the carb comment at the bottom.No idea about HP,but I seriously doubt itll be 300 crank HP(250RWHP)
That exhaust system is designed to operate the ports at 3500rpm by using a pressure signal near the front exhaust port.The secondary injectors wont be spraying any fuel until 3800 RPMS anyway,so having the aux ports open full time will serve no purpose............sorry didnt notice the carb comment at the bottom.No idea about HP,but I seriously doubt itll be 300 crank HP(250RWHP)
The aux ports extra volume and duration is not needed until higher in the revs.If you wire them open,youll just bog the engine at lower/midrange revs,every time you floor it.Its the same effect as running mechanical secondaries on a carb.You might demand full throttle right now,but if the engine doesnt have enough rpms and port flow to get things moving,the power wont be there.
Vacuum secondaries and backpressure operated intake ports both serve the function of allowing port velocity to increase as quickly as possible,by keeping the intake tract smaller.Then,when the ports are maxxed out,the extra ports will open and allow even more breathing.Opening them sooner or permanently will just induce more lowend lag,just like super big intake porting does on bridge and PP engines.
Vacuum secondaries and backpressure operated intake ports both serve the function of allowing port velocity to increase as quickly as possible,by keeping the intake tract smaller.Then,when the ports are maxxed out,the extra ports will open and allow even more breathing.Opening them sooner or permanently will just induce more lowend lag,just like super big intake porting does on bridge and PP engines.
#47
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An electrical switch set for RPM signal would probably cover it most of the time.Its a simple fix and would likely work for most occasions.
Sometimes simple RPMs arent enough,and its more about engine load and throttle position(both of which detemine intake volume and exhaust back pressure just as much as RPMs)
Say your pulling 3500RPMS in 5th and roll on the throttle.Its going to take a while for the engine to get a full head of steam and need those extra ports opened.Granted,most of us would downshift,but a factory designed system has to conform to any driving style,and plenty of grannies would just push the throttle down in 5th,expecting to accelerate.
If you have any driveability problems,you could always just weld a small steel tube to the front header pipe like the RB 13B system does,and utilize the exhaust backpressure.
RX(ZONE)....
Mazdatrix sells authentic RB parts.Its a good thing too, because Mazdatrix's service and shipping is FAR beyond RB's.All the exhaust stuff they sell is real RB.
The RB system DOES actuate the 5-6 ports on the 84-85 and 86-88 non turbo 13Bs.Since the system greatly reduces backpressure from stock,it uses a signal taken from furthur up,near the front rotor.The stock signal is taken from near the catylists.
On 89-92 cars,the smog pump air pressure opens the 5-6 ports.If you delete the smog pump on an 89-92 car,you can still open the ports by plugging into the exhaust signal port on the RB system.
Sometimes simple RPMs arent enough,and its more about engine load and throttle position(both of which detemine intake volume and exhaust back pressure just as much as RPMs)
Say your pulling 3500RPMS in 5th and roll on the throttle.Its going to take a while for the engine to get a full head of steam and need those extra ports opened.Granted,most of us would downshift,but a factory designed system has to conform to any driving style,and plenty of grannies would just push the throttle down in 5th,expecting to accelerate.
If you have any driveability problems,you could always just weld a small steel tube to the front header pipe like the RB 13B system does,and utilize the exhaust backpressure.
RX(ZONE)....
Mazdatrix sells authentic RB parts.Its a good thing too, because Mazdatrix's service and shipping is FAR beyond RB's.All the exhaust stuff they sell is real RB.
The RB system DOES actuate the 5-6 ports on the 84-85 and 86-88 non turbo 13Bs.Since the system greatly reduces backpressure from stock,it uses a signal taken from furthur up,near the front rotor.The stock signal is taken from near the catylists.
On 89-92 cars,the smog pump air pressure opens the 5-6 ports.If you delete the smog pump on an 89-92 car,you can still open the ports by plugging into the exhaust signal port on the RB system.
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Originally Posted by steve84GS TII
An electrical switch set for RPM signal would probably cover it most of the time.Its a simple fix and would likely work for most occasions.
Sometimes simple RPMs arent enough,and its more about engine load and throttle position(both of which detemine intake volume and exhaust back pressure just as much as RPMs)
Say your pulling 3500RPMS in 5th and roll on the throttle.Its going to take a while for the engine to get a full head of steam and need those extra ports opened.Granted,most of us would downshift,but a factory designed system has to conform to any driving style,and plenty of grannies would just push the throttle down in 5th,expecting to accelerate.
If you have any driveability problems,you could always just weld a small steel tube to the front header pipe like the RB 13B system does,and utilize the exhaust backpressure.
Sometimes simple RPMs arent enough,and its more about engine load and throttle position(both of which detemine intake volume and exhaust back pressure just as much as RPMs)
Say your pulling 3500RPMS in 5th and roll on the throttle.Its going to take a while for the engine to get a full head of steam and need those extra ports opened.Granted,most of us would downshift,but a factory designed system has to conform to any driving style,and plenty of grannies would just push the throttle down in 5th,expecting to accelerate.
If you have any driveability problems,you could always just weld a small steel tube to the front header pipe like the RB 13B system does,and utilize the exhaust backpressure.
So, let's say I go 13B, Dellorto or Weber side draft, the exhaust I have now, and a streetport, that should be pretty decent power-wise, right? I don't need it to be a monster, that's what my LS1 FC will be for, I just want it to be pretty damn quick.
#50
I've heard that the TII and NA motors have the same internals except for rotors and exhaust sleeves, and they didn't make a smoother exhaust sleeve for better flow. That there is no difference in power and they put it there in the NA to reduce volumn.
And that the NA is a better platform for higher power becuase of the bigger ports.
Comments?
And that the NA is a better platform for higher power becuase of the bigger ports.
Comments?