Wow I'm really glad you guys had those links to ARF. Car number 5 on the list gives me a lot of hope. 266 whp on a 13BT BP with twin 47mm ITBs. I don't quite know how they are getting them at that strange angle but they have Racing Beat logos all over their site so I'm wondering if they are running the 13BT racing beat IDA intake and then they have a small addition at the top of that to give them the extra curve. I'm trying to decide between a Hayabusa TBs with custom manifold like 23racer is running or get the RB IDA intake and get twin 48 or 50mm Borla induction ITBs... Really wish we could see what the exhaust looks like as well... So sweet though

 

I'm currently running a 6 port ITB set-up as I installed it on my stock motor. I'm making ~180whp on a stock port. The engine I'm building will be a 4 port turbo block to maximize gains.

EDIT: I'm using 48mm twin throttle bodies

 

Yeah I'm watching yours, 13bREW, and infernosg's builds but since you aren't ported and more specifically bridged I'm not exactly sure how big to go on the TBs. I really hope infernosg gets his together and tuned soon because his setup is almost exactly like I'm going to be making mine. I should probably just call Defined and do what they suggest on the intake side since I'm hoping to have them build my exhaust...

 

A little offtopic but ah, whatever... anyone know if there's an easy way to run GSL-SE style housings with later style irons? Ideally without, you know, leaking. I just realized that if flowbench results pan out the way I expect, I'll either have to machine grooves in 12A center irons and get new rotor housings, or use the ported GSL-SE housings with later grooved irons.

 

I asked this question, no good answer.

Why would you want to go backwards like that? FC rotor housings are not only more commonly available but they have far better chrome.

 

I have 6 perfect condition EProd ported GSL-SE housings that were given to me when SCCA opened up the rules to allow S4 and S5 kegs into FBs.

 

Huh. In any event, I think what I wanted to do was run an FC intermediate with GSL-SE rotor housings and 12A end housings. I know there were very good reasons for that, but I can't remember... probably a lack of good Turbo II end housings and somehow a glut of GSL-SE rotor housings. And a 13B 4-port intake manifold.

I gave up and just used a GSL-SE intermediate and made an engine mount for the passenger side, which has the benefit of constantly cracking and bending.

 

Oh well, experimentation time I guess. The joys of trying to build a better streetport than Prod I guess.

 

I have a ton of 12A intermediates but I can't use them, need the injector mounts and need the engine mount points.

Part of me thinks it is possible to mill here and tap there and PUT injector mounts in (a drilled out 1/4NPT fitting makes a fine injector boss) but they wouldn't have air bleeds, and I rather consider air bleeds to be critical for good drivabilty.

 

I'm required to use a carb for the class I'm building for anyway (and for this application don't care about drivability) but they never said all the irons have to be from the same engine. Probably being lazy and using the 12A style front cover mount given how easy it is to make it mate to chassis it's not intended for.