Hi all,
I will start by telling you abit about the build. It's going to be a car that is used both on the track and the street.
I have just got a Borg Warner s366 with 3inch down pipe and screamer, management will be a power fc, boost controller is a gizmo (not the best but will do to get it running)
Fuel system is a walbro fuel pump, sytec fuel pressure regulator,

One of my questions is what power can the stock injectors make? And what would be the good upgrade.

I'm looking at power over 400whp as the turbo is rated from 320 to 800hp,

Now for the porting I can't decide between large street or half bridge, I really want the brap but don't want it to be unreliable, or annoying to drive, but I do what a weapon on the track that can keep up with my bosses tvr's

Any info and advice appreciated

 

full bridge you'll get used to the driveability and it will smash your bosses car!

If it was just street, I'd say just go mild bridge but because you want to race just go 100%

 

The stock fuel injectors will max out at 12-13 psi if you want to leave enough headroom for safety. You'll be lucky if you have enough fuel for 10 psi with that turbo. Running an S366 at that low of a boost is far out of its efficiency range and it will have significant lag. A large port can help spool the turbo, but you would be better off downsizing to an S360 or 363. You don't need a bridge for those power goals. For fuel I recommend Full Function rails and ID 725/2000cc injectors. I can put together a full bolt on fuel system if you want.

 

I remember roasting a TVR years ago while traveling south from St. Neots to Luton (it wiped the smug right off the drivers face.. He was WELL PISSED when I slowed down and let him overtake ).. I was running twins at about 300-320 brake (as measured on a DynoDynamics down in Portsmouth, so not "yank numbers").

The OEM injectors are, at this point, horribly outdated in comparison to what is available. Also, I was maxing mine out at 13psi on STOCK turbos. As Ihor (IRPerformance) mentioned you will want new/larger injectors if you're going to run that turbo.

If it were me in your shoes, I would go with a slightly smaller turbo and more mild porting with a focus on response and mid-range umph as opposed to peaky dyno numbers. Well sorted sequential twins are a BLAST in the UK because they have response EVERYWHERE. If you're just looking to have a play at Santa Pod than go with the big ports and big turbo. If you want a thrill on the country lanes between yours and there than go smaller.

Just my 2p.