What are the benefits of a 20b single turbo over a big single 13b? I know more torque but anything else?It doesn't look like much more horsepower. both are capable of tons. reliability? please fill me in. thanks

 

I believe the 20B has a wider powerband, plus 20B single turbo makes tons more power than 13B single turbo. The 3 rotor horsepower figures you have seen were probably still on the stock twins converted to non sequential, you can do this with a port job and get 550hp out of them or at least pettit does. You BP or PP a 20B and stick a big single turbo on it and the numbers are mind boggling.

 

The cost of each project appears close. A 13b with big power or a 20B with medium power. The 13BT has to be tuned out to do what a ported 20B will do with little effort. And you still don't have the tourque. It seems a 20B that was mild would last much longer than a 13B that was wild. Thats what I am working toward. A N/A 20b in my truck.

 

That's basically why I went with the 20B, also. I need to keep the noise down, though, so I had to go with a turbo. Had I stuck with the stock 20B turbos (550bhp potential), I would have been able to budget my project fairly closely to what a 550bhp 13BT would have cost.

 

I have read that you have to run a stock ECU with the stock twins. How would you use the stock turbos? I have read you can't use the stock ECU in an RX-7. Someone mentioned converting to not sequential twin turbos. How is that done?

 

the 3 rotors sequential turbo system works exactly like the 93-01 rx7's system. the same things apply.
if you have the stock ecu it will run the sequentials. most aftermarket ecus wont run them correctly, but you cannot use the stock ecu without ALL of the stock electronics. you can make the twins non sequential its almost the same as doing it to an rx-7

mike

 

Do you make the exhaust gases go to the bigger turbo or both?

 

both to make it non sequential.

mike

 

20B with streetport and stock twin turbos should make about 500-550 hp with 12-14 psi. Upgrade to a large single turbo and you are looking at 600hp+

It would cost CRAZY lots to get a 13B up to 500-600 hp, probably about the same, or maybe even more, than the 20B swap.

The 20B will have much more torque, a wider powerband, and far better reliability. If you aren't that mechanically inclined and can't do all the work yourself, then maybe a 13b-t would be the better choice, but as far as performance goes... 20B can't be beat (well... 26B haha)

 

20Bs require less boost to make big power. To make ALOT of power with a 13B you have to crank up the boost. A 20B can make a ton with very little. Id say thats why people claim that they are more reliable because of the chances of popping an engine at 10 psi instead of 20.

 

you can make the same power with less stress on the motor

mike

 

at the cost of an extra 130lbs. (according to car & driver) of weight though - and also weight closer to the front end of the car.

 

A big turbo and FMIC are also extra weight up front, but you still see a lot of people putting them on their car, anyway.

 

plus you are taking out the ac and ps too

mike

 

Which automatics that came to the US fit the 20B. Will the 20b auto be usable without the Cosmo CPU? If not what exactly does the 20B cpu control that can't be managed another way?

 

the trany should be a lot like an mpv or an fd one. i would also bet that the fd control unit is similar to the cosmo one.

mike

 

How much will an NA 20B put out?

 

Up to 500bhp on a PP professionally-built race engine. A street-legal NA 20B would probably get around 300bhp before it started getting too noisy.

 

I just posted at a local import forum here and there is a guy that claims the twin turbo supra engine is the best engine/hp you can get with out having to "build" it or put different rods/pistons in it. I'm thinking the 20b with a big single or two turbos could give it a run for it's $.

So my queston is how much bhp can you get out of the stock 20b ports? anywhere close to a 1000hp?

 

can you get 666hp out of a stock port 13B? (how evil )

Arguably *all* performance rotaries have stock internals... after all we have to run OE e-shafts and rotors

 

You mean torque is not enough? You need to go drive one!

The 13B will peak out at around 600hp to the wheels.&nbsp The 20B is good for 900hp to the wheels.

Unless you're like those crazy *** drag racers like Abel Ibarra or Dennis Marquis[sp?], then the limit gets up'd to 700hp for the 13B-REW and 1000hp for the 20B.



-Ted

 

LOL, no, but you may be able to get that out of stock-port 20B. Hmm, do stock 3Gen housings count?

 

if they're stock....


mike

 

Sorry, but I consider even using ported housings to be "stock" since they are Mazda parts... what I mean is we have to get all of our internals from Mazda - everything we use is factory-based stuff, there is no aftermarket other than a couple companies making alternative apex seals.

I know we can get 666hp from a 20B... My point was, someone asked if you can get 1000hp from a stock port 20B, my reply was well, can you get 666hp from a stock port 13B?

 

20bs sound tight as hell