LTnone

So here's the plan so far, any input/thoughts would be appreciated, we'll see how things go...
When I bought the car, it had (has) A/C and Smog delete, catback exhaust (catted x to 40's), and a crappy CAI. Here's a list of things I would like to do before winter, and during winter-

Before:
-3.73's/Rearend rebuild
-BBK LT's, O/R H-pipe, and cutouts (I know the LT's are gonna hurt me now, but they're a long term investment)
-BBK U/D pullies (already have these, just not installed)
-BBK CAI

During Winter:
-Trick Flow H/C/I (This one)
-24lb injectors
-255lph fuel pump/new filter
-Short Throw shifter (hoping to prolong the life of the T5 a bit...)
-___mm MAF
-___mm TB

This is where the question comes in... MAF and TB sizes are up in the air right now. Can anyone give ranges of effective size for either? i.e. a 70mm TB is good to __hp, etc...
I was thinking 70mm TB and 76mm MAF, is that acceptable/optimal? Thanks for the input

FiveLiterRiceEater

70 and 76 sound good to me. hard to say what hp numbers youll gain, but with a new intake and that trickflow cam you should suck through a lot more air. and then youll have nice heads and headers to get rid of everything. so you should gain a lot of power with all that. youll be suprised what you get. itll feel like a brand new car

mrbigshot

the tb and maf does not have a maximum size, you could have a 100mm (1000 cfm) throttle body but it wont flow more air than the engine is capable of using, to big will make you lose average hp and make throttle responce poor. a 70mm tb could support over 650 hp on a boosted application.you will be seeing about 350 and trick flow reccomends no bigger than a 70mm for that kit. for the maf i would go with a 73mm or 76mm. your combo only requires 21.65# of fuel but thats above the maximum reccomended duty cycle of 80% for the injectors. consider this engine the limit for 24# injectors. keep in mind you wont be full throttle all the time so 24#'s will be ok. if you want to add more power in the future you will need 30# or 36# pound injectors. you also could use a smaller fuel pump if you wanted but i think its good you are using the biggest you can get, if you upgrade the in tank lines you could support 775hp!

LTnone

Thanks a lot, I'll start looking into 30's as well. How did you calculate fuel needs? Also, I've been hearing stuff about a fuel pressure regulator. How necessary is this/how does it help?

mrbigshot

fuel pressure regulators are a excelent tuning tool if you can read your engines air/fuel ratio. less fuel pressure will lean it out and more will make it rich. common practice is to take 2-3 psi off a stock motor to see 5-9 hp gain. if you have a wide band o2 sensor or a scan tool this is helpfull.

engine max hp x .50 / number of injectors

.45 lower volumetric efficency motors (under 60%)
.50 for higher volumetric efficency motors (over 60%- hot engines)
.55 for boosted engines
.60 for nitrous/ promod motors

in your case the engine was dynoed at 350hp x .50 /8 = 21 psi

LTnone

So that means that injectors that are too big will actually hinder performance? And then, that being said, a regulator would effectively make any size injectors perform at the optimal pressure?