I've got an cosmo 13b as well ...you will make much more than 250 with that..the motor is making 230 at 6psi..12-14 psi is possible but you would be safer at 10 psi on the stock ones. you can run 14 easly even more if you let BNR play with them. you don't need to port the motor. the ports are huge..I can't remember who posted it but someone did a monster street port on an fd and put it side by side with a cosmo stock..the fd monster port was a hair bigger..all you really need to do is clean up the rough edges in the ports. now the exhaust ports are smaller so I'd suggest putting FD exh. sleeves in or porting the cosmo ones...but you don't really need to. oh yes use a stand alone ecu...and you won't be able to pass smog with that engine. well not in california anyway..not sure about anywhere else. Block off as much crap as possible.

 

That would not surprise me.



Be careful with your tuning, as it will be way past the capabilities of the stock 4 x 550 fuel injectors. I have found the 4 x 550's are only good for 250bhp at the flywheel!





Of course more boost will degrade reliability, but with the stock twins should perform fine under 15psi. I do not have very good results running the carbon seals past 15psi, so I would recommend keeping it under 15psi.





-Ted

 

if you're going to upgrade anyway, you may as well get the better pump now, also cheaper. That is unless you're getting a used fd pump, which wouldn't be my first choice. When dealing with fuel systems, its best to not cheap out as it can be the difference between your engine living or not living. I've known a couple guys running pretty fast with just the stock FD fuel system, injectors AND pump, but they do get extremely lean at that point too. I wouldn't personally do it and i don't suggest that you do either.

 

good stuff



i will give a little more info into my plans, i will be making up a new exhaust manifold and fitting the cosmo twins (non seq) to a mildly ported s4 13bt. I will not be running efi, as i am going to run the motor on straight LPG (BBQ gas ) Here in aus there is a place called gas research that make LPG throttle bodies, so i will be using one of them to take care of the fuel. And most probably a 12a turbo boost retard dizzy. Not the best setup but remember it is my daily driver, and LPG is less than half the price of petrol. Also they are becomming popular over here with good results



Are the carbon seals in the turbos expensive to replace? And are they difficult to come by? Also what are your thoughts on the cosmo twins versus the stock s4 turbo? Are they a better choice?



thanks



Lance

 

Since your rebuilding it, I would go ahead and replace the rotor housings to TII(Cosmo 13B ports are smaller).



I wouldn't bother with carbon apex seals. For the price, I would go ahead and purchase the rotary aviation apex seals.



As far as intake porting, I think you will find that the port sizes are already quite large. Of course a little more won't hurt. I used a racing beat template that seems "conservative" compared to others around but still seems to make good power.



As far as your fuel pump....FD pump will NOT suffice. Maybe 2 FD pumps...but definitely not one.



I would recommend(for your fuel) to go ahead and run stock 550's with 1600's as secondaries. You'll of course have to make your own fuel rail or figure a way to use the stock top feed ones.

 

think they talking about carbon turbo seals, not apex.

 

I would change out the exh sleeves for ones from a T2

 

the cosmo runs 10psi on the first turbo and 8-9 on both together, so its 230hp @8-9psi

 

he must be thinking of the cosmo 3 rotor

 

found this can anyone make the boost specs into bar or psi??? http://www.dmrh.com.au/jcspecs2.htm