4 Port 13B
08-31-10, 10:48 AM
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What series 13b engine are you working with to start with?
FB 13bs can use 12A plates to make a 4-port
FC 13bs use TII or RE plates
Intakes would need to be fab'd if crossing S4/S5.
"NEW" would be cost prohibitave - typically get a good 13B core engine (S5 preferred) and swap out the appropriate 4-port plates.
FB 13bs can use 12A plates to make a 4-port
FC 13bs use TII or RE plates
Intakes would need to be fab'd if crossing S4/S5.
"NEW" would be cost prohibitave - typically get a good 13B core engine (S5 preferred) and swap out the appropriate 4-port plates.
08-31-10, 12:13 PM
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there are a couple of ways to do it, depending on what year engine you wanna use.
if you want to build an early style 4 port 13B, you use your 12A side plates, GSL-SE rotor housings. and your choice of 13B eshaft/rotors/stat gears.
the newer way is to take a turbo FC or FD block, and remove the low compression turbo rotors for the high compression NA rotors.
the early motor would use the early 13B intake, which are mostly carb. EFI you could use the GSL-SE center iron too.
the FC/FD engines are EFI, and you could just use the stock intake, although its not quite ideal
if you want to build an early style 4 port 13B, you use your 12A side plates, GSL-SE rotor housings. and your choice of 13B eshaft/rotors/stat gears.
the newer way is to take a turbo FC or FD block, and remove the low compression turbo rotors for the high compression NA rotors.
the early motor would use the early 13B intake, which are mostly carb. EFI you could use the GSL-SE center iron too.
the FC/FD engines are EFI, and you could just use the stock intake, although its not quite ideal
08-31-10, 03:41 PM
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I'd like to use newer components that are still in production. I thought I remembered reading that using T2/FD plates wouldn't work as well though because of their design (for an N/A app). The engine will go in to an '85 GSL and I've researched all of the supporting junk for putting one in, I'm looking for info on which will perform better for my app.
The car will be street driven, I would like to take it to a track for "fun days" but having never done anything like that before I imagine it will be mostly a street car. I would like to run the engine with a Haltech fuel only controller, TBI and use a distributor for ignition. Having the car fuel injected would it be possible to run either a 1/2 bridge, full bridge or large streetport "comfortably" on the street? I understand if these questions have been went over before and I'm trying my fellow forum member's patience, I apologize if this is the case. I tried to search this stuff at first (if you look at my post count, I'm not a big fan of posting just to repeat questions that have already been asked and answered). I'm looking for feedback from people who have run one of these engines (either with 12A or 13B-T/RE/REW plates and the accompanying rotors) N/A on the street/light track work with a fuel injection system and a good amount of port work. What type of porting did you have? Injection system? Ignition system? Transmission? How did you feel the car performed both on the street and the track? Was the powerband too narrow and high for street driving?
This car won't be a daily driver but I would like to be able to take it out and enjoy it, I love the way the rotary engine sounds with heavy porting... Simply beautiful.
The car will be street driven, I would like to take it to a track for "fun days" but having never done anything like that before I imagine it will be mostly a street car. I would like to run the engine with a Haltech fuel only controller, TBI and use a distributor for ignition. Having the car fuel injected would it be possible to run either a 1/2 bridge, full bridge or large streetport "comfortably" on the street? I understand if these questions have been went over before and I'm trying my fellow forum member's patience, I apologize if this is the case. I tried to search this stuff at first (if you look at my post count, I'm not a big fan of posting just to repeat questions that have already been asked and answered). I'm looking for feedback from people who have run one of these engines (either with 12A or 13B-T/RE/REW plates and the accompanying rotors) N/A on the street/light track work with a fuel injection system and a good amount of port work. What type of porting did you have? Injection system? Ignition system? Transmission? How did you feel the car performed both on the street and the track? Was the powerband too narrow and high for street driving?
This car won't be a daily driver but I would like to be able to take it out and enjoy it, I love the way the rotary engine sounds with heavy porting... Simply beautiful.
08-31-10, 04:06 PM
#5
Either way will get you there and work very well. FD has the best oil pump and can only be used with FD front plate. T2 blocks work great in N/A application with N/A rotors, T2 oil pump is much improved. FD's can be ported HUGE. All this has been done many times before.
Since quality used pre 1986 engine components are hard to come by, and no pre-1986 front plates are not available new, in the long run you'd be better off with 1986+ parts from an availability standpoint alone. Which ones are up to you.
I've run a 12a streetport on a daily driver with occasional track day time and it was great. Since 12a rotor housings are NLA I would steer clear of the 12a motor. I own a 12a full J bridge and I would never consider it a daily driver. The motor kicks and bucks below 4000rpms due to all the overlap. The car literally jerks forward and back. MPG horrible. 7000rpm+ beautiful. Narrow powerband. Most people that small bridge or 1/2 bridge don't drive it daily. And mostly don't drive it long distances either.
For a street car do a large streetport. Keeping the 5th & 6th port actuators working isn't a bad idea either on a 2nd gen n/a motor. Helps with low end.
Make sure you have the 85psi+ oil pressure relief and an oil pan baffle plate. Competetion oil control ring SPRINGS and FD corner seal SPRINGS. Balancing helps a ton too- smoother. ALL New seals and quality rotor housings - most used housings for sale are junk in disguise. Rev limit @ 8500 MSD 6AL or you'll chew bearings.
Since quality used pre 1986 engine components are hard to come by, and no pre-1986 front plates are not available new, in the long run you'd be better off with 1986+ parts from an availability standpoint alone. Which ones are up to you.
I've run a 12a streetport on a daily driver with occasional track day time and it was great. Since 12a rotor housings are NLA I would steer clear of the 12a motor. I own a 12a full J bridge and I would never consider it a daily driver. The motor kicks and bucks below 4000rpms due to all the overlap. The car literally jerks forward and back. MPG horrible. 7000rpm+ beautiful. Narrow powerband. Most people that small bridge or 1/2 bridge don't drive it daily. And mostly don't drive it long distances either.
For a street car do a large streetport. Keeping the 5th & 6th port actuators working isn't a bad idea either on a 2nd gen n/a motor. Helps with low end.
Make sure you have the 85psi+ oil pressure relief and an oil pan baffle plate. Competetion oil control ring SPRINGS and FD corner seal SPRINGS. Balancing helps a ton too- smoother. ALL New seals and quality rotor housings - most used housings for sale are junk in disguise. Rev limit @ 8500 MSD 6AL or you'll chew bearings.
08-31-10, 05:24 PM
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i agree, if you're serious, the more new parts the better.
you can find decent eshafts, and stat gears used, and irons too, probably.
but rotor housings, and ALL of the seals and gaskets should be new. if you can afford it, rotors too.
you can find decent eshafts, and stat gears used, and irons too, probably.
but rotor housings, and ALL of the seals and gaskets should be new. if you can afford it, rotors too.
09-01-10, 01:48 PM
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I just put one in my car, but it's carbed. 12A plates and front cover, REW housings, GSL-SE 13B rotating gear since it's what I had and the build was way over budget as it was. Was planning to use the housings too but they were garbage. Using a Sterling carb with an RX4 intake mani redrilled for the Nikki bolt pattern. So far have not taken it over 6K, but the power is there and it's great on the street. Once I kick into the secondaries it just pulls. Can also get it to idle at 550RPM no problem. Haven't raced yet and won't until next year most likely. Fuel consumption is noticeably higher but nothing to complain about. Using a GSL-SE 5spd. Once I get it tuned I'd be happy to see 170 at the wheels with my RB exhaust. Might redo the exhaust if I feel it needs to be done but I love the sound of it, so maybe not.
Pics of the porting can be seen on page 10 of my cardomain page.
http://www.cardomain.com/ride/2322069/10
Pics of the porting can be seen on page 10 of my cardomain page.
http://www.cardomain.com/ride/2322069/10
Trending Topics
09-01-10, 08:29 PM
#9
I run a 12A 1/2-sp 1/2-bp in the widebody. Link is the last line in my sig. The ONLY way I will ever run an NA 1/2-bp on the street, (12A or 13B), is with a fully divided intake manifold and progressive dual 2 barrel carbs or throttle bodies. Forget about even thinking of running a full bridge NA on the street. The point here is horsepower AND driveavility. I've run single 2 barrel and 4 barrel carbs, vacuum and mechanical secondaries at different times on this engine. The difference is night and day between a fully divided intake/carb and one that has even the slightest bit of overlap. The dual Weber DCD carbs I'm running now do just that. Yes Virginia, you can play with Rudolph and eat him too, just eliminate the overlap.
That overlap takes all the fun out of driving and it can quickly become tedious and tiresome.
My ideal 13B 4-port would have all the oiling/balancing/clearancing/apex seal mods, (ceramic) needed to turn 9k rpms on an extended daily basis. Custom built intake manifold to take advantage of an Ito primary street port, secondary bridge port, independent and progressive primary/secondary throttle bodies. TII race ported exhaust. SDJ headers. 2" dual exhaust merging to 3" near the rear axle. 2 pre-silencers are a must with the porting and exhaust diameter. Fully functioning MegaSquirt allowing for tuning on the fly, spark and fuel.
Now, if this is done right, the engine should have the manners, idle and exhaust note of a healthy street port in the low end rpms and the insane scream of a bridge port in the upper rpms. A set up like this should put out 250-275 bhp, (guesstimate) with a much broader torque curve than a full bridge port.
Happy Dreaming.
.
.
.
.
.
.
That overlap takes all the fun out of driving and it can quickly become tedious and tiresome.
My ideal 13B 4-port would have all the oiling/balancing/clearancing/apex seal mods, (ceramic) needed to turn 9k rpms on an extended daily basis. Custom built intake manifold to take advantage of an Ito primary street port, secondary bridge port, independent and progressive primary/secondary throttle bodies. TII race ported exhaust. SDJ headers. 2" dual exhaust merging to 3" near the rear axle. 2 pre-silencers are a must with the porting and exhaust diameter. Fully functioning MegaSquirt allowing for tuning on the fly, spark and fuel.
Now, if this is done right, the engine should have the manners, idle and exhaust note of a healthy street port in the low end rpms and the insane scream of a bridge port in the upper rpms. A set up like this should put out 250-275 bhp, (guesstimate) with a much broader torque curve than a full bridge port.
Happy Dreaming.
.
.
.
.
.
.
09-02-10, 08:44 AM
#10
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Yeah my builder had a machine shop cut the coolant seal grooves into the housings. Wasn't too expensive. Well for me it wasn't. They misquoted him and that's the quote he gave me, so when they changed it he sucked up a bit of the cost. It's all these little things that killed my budget on the build.
09-02-10, 10:16 AM
#11
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Can't wait to see your car in action with all the new improvements you've made on it Chris. Next year is too far away, you've got to come over for at least one race this year. 
.
.
09-02-10, 10:58 AM
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I run a 12A 1/2-sp 1/2-bp in the widebody. Link is the last line in my sig. The ONLY way I will ever run an NA 1/2-bp on the street, (12A or 13B), is with a fully divided intake manifold and progressive dual 2 barrel carbs or throttle bodies. Forget about even thinking of running a full bridge NA on the street. The point here is horsepower AND driveavility. I've run single 2 barrel and 4 barrel carbs, vacuum and mechanical secondaries at different times on this engine. The difference is night and day between a fully divided intake/carb and one that has even the slightest bit of overlap. The dual Weber DCD carbs I'm running now do just that. Yes Virginia, you can play with Rudolph and eat him too, just eliminate the overlap.
That overlap takes all the fun out of driving and it can quickly become tedious and tiresome.
My ideal 13B 4-port would have all the oiling/balancing/clearancing/apex seal mods, (ceramic) needed to turn 9k rpms on an extended daily basis. Custom built intake manifold to take advantage of an Ito primary street port, secondary bridge port, independent and progressive primary/secondary throttle bodies. TII race ported exhaust. SDJ headers. 2" dual exhaust merging to 3" near the rear axle. 2 pre-silencers are a must with the porting and exhaust diameter. Fully functioning MegaSquirt allowing for tuning on the fly, spark and fuel.
Now, if this is done right, the engine should have the manners, idle and exhaust note of a healthy street port in the low end rpms and the insane scream of a bridge port in the upper rpms. A set up like this should put out 250-275 bhp, (guesstimate) with a much broader torque curve than a full bridge port.
Happy Dreaming.
.
.
.
.
.
.
That overlap takes all the fun out of driving and it can quickly become tedious and tiresome.
My ideal 13B 4-port would have all the oiling/balancing/clearancing/apex seal mods, (ceramic) needed to turn 9k rpms on an extended daily basis. Custom built intake manifold to take advantage of an Ito primary street port, secondary bridge port, independent and progressive primary/secondary throttle bodies. TII race ported exhaust. SDJ headers. 2" dual exhaust merging to 3" near the rear axle. 2 pre-silencers are a must with the porting and exhaust diameter. Fully functioning MegaSquirt allowing for tuning on the fly, spark and fuel.
Now, if this is done right, the engine should have the manners, idle and exhaust note of a healthy street port in the low end rpms and the insane scream of a bridge port in the upper rpms. A set up like this should put out 250-275 bhp, (guesstimate) with a much broader torque curve than a full bridge port.
Happy Dreaming.
.
.
.
.
.
.
Last edited by timedrapery; 09-02-10 at 11:00 AM. Reason: Grammar
09-02-10, 11:18 AM
#13
Why not just start with an early 13B 4 port longblock?
I have 2 in inventory now
Both are low mile Jspec engines with under 40,000 miles
one is out of a Luce, the other is early cosmo
100PSI or better compression on both housings guaranteed
$1000.00 plus shipping is what I am asking for each longblock
Here is a pic of 1 of the 2 I have
I have 2 in inventory now
Both are low mile Jspec engines with under 40,000 miles
one is out of a Luce, the other is early cosmo
100PSI or better compression on both housings guaranteed
$1000.00 plus shipping is what I am asking for each longblock
Here is a pic of 1 of the 2 I have
Last edited by Japan2LA; 09-02-10 at 11:32 AM.
09-02-10, 11:24 AM
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Why not just start with an early 13B 4 port longblock?
I have 2 in inventory now
Both are low mile Jspec engines with under 40,000 miles
one is out of a Luce, the other is early cosmo
100PSI or better compression on both housings guaranteed
$1000.00 plus shipping is what I am asking for each longblock
I have 2 in inventory now
Both are low mile Jspec engines with under 40,000 miles
one is out of a Luce, the other is early cosmo
100PSI or better compression on both housings guaranteed
$1000.00 plus shipping is what I am asking for each longblock
09-02-10, 12:27 PM
#17
Why not just start with an early 13B 4 port longblock?
I have 2 in inventory now
Both are low mile Jspec engines with under 40,000 miles
one is out of a Luce, the other is early cosmo
100PSI or better compression on both housings guaranteed
$1000.00 plus shipping is what I am asking for each longblock
Here is a pic of 1 of the 2 I have
I have 2 in inventory now
Both are low mile Jspec engines with under 40,000 miles
one is out of a Luce, the other is early cosmo
100PSI or better compression on both housings guaranteed
$1000.00 plus shipping is what I am asking for each longblock
Here is a pic of 1 of the 2 I have
09-02-10, 04:39 PM
#20
Old [Sch|F]ool
For performance use, I wouldn't consider anything older than FC rotors. The 2mm seals and 12-pin rotor gears are way more reliable for high RPM use than the old 3mm/9-pin rotors.
Plus 2mm seal engines are not that difficult to come by with decent rotor housings, while 3mm seal engines destroy rotor housings pretty much as the primary wear item.
Count me in on the 1/2-bridge Turbo II block bandwagon.
Plus 2mm seal engines are not that difficult to come by with decent rotor housings, while 3mm seal engines destroy rotor housings pretty much as the primary wear item.
Count me in on the 1/2-bridge Turbo II block bandwagon.
09-02-10, 08:33 PM
#21
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No can do. I won't be home until after the 6th and the car is parked for the rest of the year. I've got other priorities that I've been shirking because of the car.
09-03-10, 04:40 AM
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For performance use, I wouldn't consider anything older than FC rotors. The 2mm seals and 12-pin rotor gears are way more reliable for high RPM use than the old 3mm/9-pin rotors.
Plus 2mm seal engines are not that difficult to come by with decent rotor housings, while 3mm seal engines destroy rotor housings pretty much as the primary wear item.
Count me in on the 1/2-bridge Turbo II block bandwagon.
Plus 2mm seal engines are not that difficult to come by with decent rotor housings, while 3mm seal engines destroy rotor housings pretty much as the primary wear item.
Count me in on the 1/2-bridge Turbo II block bandwagon.
09-03-10, 04:56 AM
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I know this is an Australian company, I'm not sure if anyone here in the States is running anything like this setup but if somebody is, please let me know how you're liking it. Also, Trochoid, is this anything close to what you would run if you were building a 13B? Peejay?
EFI Hardware IDA Throttle Body Kit - Suit Mazda 12A, 13B Rotary
http://www.tweakit.net/shop/product_...roducts_id=117
Mazda RX7 IDA Weber Manifold - 13B Turbo
http://www.tweakit.net/shop/product_...roducts_id=107
What are your thoughts on these products?
EFI Hardware IDA Throttle Body Kit - Suit Mazda 12A, 13B Rotary
http://www.tweakit.net/shop/product_...roducts_id=117
Mazda RX7 IDA Weber Manifold - 13B Turbo
http://www.tweakit.net/shop/product_...roducts_id=107
What are your thoughts on these products?