20b engine and porting

[maz13b]

I have serios of questions I wanted to ask.

Would anyone know if 20b engine from cosmo is a straight fit to an fd3s RX7.

When street porting is done what exactly do they do to the engine and would anyone know the link or something on how to do it. Same question for bridge porting.

Would 20b engine be better for producing high bhp or overall 13b engines are better.

Anyone knows any websites that sells performance items for 20b?

Thanks for taking your time reading and replying to this thread.

Maz

[Timmy]

a 2ob conversion costs alot. £10k+ require shortening propshaft new mounts or moving steerin stuff i think. Obviously the 20b is capable of more bhp and torque.
Should be able to find lots under porting on here.

[maz13b]

Well, £10k+ with me already having the engine?

[Timmy]

I don\'t know alot about it i started to have a little look than relised the amount of money it would cost and relised the 13b provide pretty much everything i need.

[BlitzBoy]

try rx7club.com they have a 20b section for the conversion.
You need the engine plus 10k
eg custom subframe kit,Motec/Haltech/microtech ECU,custom intercooler,big single turbo kit,customise the propshaft,coilovers with adjustment for the extra weight upfront,custom downpipe and exhaust,Fuel system, etc etc

[shaunwil]

http://www.rx7club.com/showthread.php?t=644417

Shaun

[FD3UK]

Leave it where it was intended,more money to spend on improving it;)

[maz13b]

Hello everyone and many thanks for the links and advice.  Importing a mazda cosmo cheap would not be a problem since I have started my own importing business.

I smell 20b conversion coming up.

Anyone got any links for porting the engine?

[slippers]

Please stop this cruelty now.

If the cosmo is beyond repair etc then fair enough, but dont import a 20b just to rip it apart!

Think of the children.

[BlitzBoy]

The porting principles for the 20B is the same as the 13B, you can get a dvd on porting I believe or buy some porting templates from racing Beat or Pineapple, or get a rotary tuner to port the plates for you

[sadgoth]

Why not leave the 20b in the cosmo, change the box for a 6 speed sequential and port the hell out of the engine? You\'d have a really fast street sleeper and nowhere near as common as those FDs

[FD3UK]

Something like this....

[shaunwil]

Definitely leave it in the cosmo ! They look awesome and go like stink !

If you can get a front cut of a 20b cosmo then fine but they are getting rarer !

Shaun

[dthebuk]

porting http://www.mazdarotary.co.uk/index_files/page0002.htm

basically (to my limited knowledge) you cut and polish the intake ports, usually using a stencil, unless you designing your own port. And the exhaust port can bee bored out for a larger diameter.

a street port is just making the intake ports bigger


also how much power are you looking for? I think the 888bhp dragon 7 was 2 rotor

[RobMatthews]

a little off topic but were all the cosmo\'s auto?and is there any straight swaps for the gearbox?