20b Cosmo Engines

[Paul1982]

1) How rare are they?

2) How reliable are they?

3) What is the official bhp figures for them?

4) What is the gearbox different to the FD?

5) How easy are they to Tune?

6) Would sourcing one of these engines be worth doing if my car ever needs a rebuild??

[peterwolds]

Sure that Kevin will answer this as knows them inside out

[sadgoth]

the conversion from a 13b to a 20b is a BIG job, you are looking at a LOT of £££!

They are more powerful, loads more torque, as stock the 20b is officially 280bhp (but that is with very restrictive inlet manifold, exhausts ect)

It is a lot of work though and if done properly you won\'t get much change from £15k though

[Paul1982]

But i thought you could pick up a 20b cosmo for little money and transfer the engine over :-(

[sadgoth]

nope, engine is bigger, heavier and mounts are in the wrong place. It has been done by a few people on here, but it isn\'t the cheapest way of getting more grunt!

[elford_tim]

Not to mention that 20B Cosmos seem to be going up in price. Doesn\'t surprise me as I doubt that there are a lot of them left.

[banned advertiser]

2 in crates, just short block only £2500.
Have no idea of condition.

[Paul1982]

Would all the 2 rotor parts bolt straight onto the 3 rotor?

[Martiny]

Would all the 2 rotor parts bolt straight onto the 3 rotor?

no way, friend,

How can the Exhaust, inlet and turbo system be the same?

Then what about the ecu? we need spark and fuel for 3 rotors now.

I think the gearbox does bolt on, but then, you need to make some engine mounts !

A proper job means moving the whole engine and gearbox backwards, or you upset the handling by adding weight at the front.

etc, etc....

[Paul1982]

So in other words \'fook it\' and just go for a single turbo or ported engine for cheaper money!!

[sadgoth]

So in other words \'fook it\' and just go for a single turbo or ported engine for cheaper money!!

that is the common answer once the 20b conversion has been looked into!

[FD3UK]

2 in crates, just short block only £2500.
Have no idea of condition.

Gary, just checking is this each or for both?

[kev-yorks]

The 20b conversion is a lot of work and money for little gain unless you are really going to push it, as the same power figures can be have from a 13b. Yes there is loads more torque and off boost power but how much will the fd chassis take? The conversion to do right will cost 15k+ just ask Normski. A fd box can be grafted onto the 20b but it is not a straight bolt up job and as mentioned you will have issues with both engine and gearbox mounts, steering rack issues, a custom sump to make etc etc. Tuning is the same as any rotary but if you scew up it can cost you big time as some of the 20b parts are no longer made by Mazda. To sum up there is no logical reason to put a 20b in a fd road car (but when has logic ever come into anything rotary) if you really must chop one of the few rare Cosmo\'s left then go for the 13b re but even this is not a straight forward bolt in ask John Clayton (Warthog)
Regards Kevin

[Scott Zimny]

Gary, just checking is this each or for both?

Same question as well...may be interested??:yes

Regards Scott:Thumbsup!

[Martiny]

So in other words \'fook it\' and just go for a single turbo or ported engine for cheaper money!!

If you\'re looking for up to 400 hp, yes.

I suppose if you want to go way beyond this , then the 20B option is better.