NA vs FI debate

[droptopman]

in the locked thread, the turbo vs NA build came up.

this has been beaten to death in nearly every car forum ever created, but here is the overview

NA (naturally aspirated)
includes:(minimum)
I/H/E
cams
adjustable cam gears
standalone engine management (stock just won't do)
mild porting and polishing
bigger injectors
(real power parts)
upped compression 11:1 to 12:1
lightweight EVERYTHING
blueprinted and balanced everything.
machining to valves...

pros-
instant throttle response
power comes on very differently- its typically linear and redlines of built motors (fully blueprinted) can be insane. sounds amazing. raw- oldschool- you can get the popping and fire out the back.
cons-
lower eventual power goals-
more expensive- a real NA build starts at about 5k... goes up to what you are willing to spend.



FI
includes:
yall know what goes here.

pros- much cheaper than equivalent power on a N/A car
much easier to add more power

cons-
lag. doens't matter if its a turbo or a supercharger- it WILL HAVE MORE LAG THAN AN N/A CAR. with a properly sized turbo and good routing, you can get minimal lag, or with certain types of superchargers. and there are superchargers that do lag worse than a properly setup turbo.

if you are serious about a true NA build, i take my hat off to you.

i will put it this way.

i have a miata.

stock 100 whp.

goal 150 whp.

na build- 4k. serious engine management, lots of tuning, headwork, time and money.
turbo build- if you have a 1.6- $1500 for a greddy kit.
if you have a 1.8- $1500 for a homebrew kit, or about 2200 for a reputable kit with a piggyback controller.
supercharger- 2200 for a JR racing supercharger. full kit.

goal- 200ish whp.

N/A build- will cost you 6k. documented cases. and even then, its a hard goal to reach.
turbo- homebrew kit (for 1.8)- $1500 if you get lucky on ebay parts and have the right year (megasquirt isn't out for my car yet.)
supercharger- 3500. FFS kit. piggyback controler.

200 hp is the upper limit on the miata, whereas forced induction on the stock block, stroked motor, fully built on a turbo is currently 493 hp. turbo will net more hp, but you will lose things. its a give and take relationship. if you can be happy with what you have, NA might be the way to go. if you like to constantly tweak and increase, FI is the way to go, much more headroom to grow.

[Broken]

easy answer to easy question IMO

for big displacement engine (4.5 litters and up, small and big blocks, etc) N/A willproduce enough power to not need a snail, and its a lot cheaper than a blower. Though a blower wouldnt be bad aidea, I would keep it N/A.

small displacement enignes (3.5 or less, V6, 4 cyls, rotaries) blow all the way. no way no how a N/a setup will give you the power and output a turbo/supercharger/turbocharger will ever give. Besides, like you mentioned, is a heck of a lot easier.

my .02 cents. Of course, I have a turbo lol. but ive had n/a's and I know the PITA it is to tune.

[rynosilver3]

mat go forced induction you know you want more power i mean hell your car handles really damn good might as well make it go fast too

[droptopman]

i am waiting for a few more things to be made before i go FI...

firstly engine management. i want a megasquirt ecu. but that would make me loose my obdII port... unless they make it compatible.

turbo is still being debated- depends if i get the job at the vw place- in which case i will be running 7 psi boost, no intercooler on a K03 turbo. if not, its between the garret gt26 and gt28 series turbos. either would have an 18 to 19 inch intercooler. depends on what was cheaper. most likely one of the chinese knockoff turbos- most have found them to be fairly durable- no issues with them so far.

most likely 550 cc injectors...

piping would have to be custom... not a huge issue.

DP would be made by begi engineering...

id say all in all only about 2k with tuning. not too shabby... considering my goal is to put down around 200-220 whp. i can't afford a new trans or rear end. so i will keep it with a quick spool and medium boost. i am going for a moderate power goal, just to keep from blowing stuff up. when i get out of college, i might invest in the 6 speed, different rear gear ratio and up the boost when its not my daily car.

if i go with the k03 turbo, i think i could get like 180 hp- and keep on the stock injectors to simplify everything. no intercooler- would be less than 1500 for the project.

[RareAJ]

I am moving this to another section of the forum, going to look where though give me a sec.

[droptopman]

anyone else planning a serious engine build? not just a kit, but a real DIY turbo/super/ n/a build up to get some serious power, rediculous redline, or monster torque? if you are, post your expected setup and why you are going that route.

[NOmz3]

I'm planning on a serious full NA build for my 3. I'm waiting for the warranty to go up in smoke.

Once thats out the way, I'm going to look into cam options along with the a full standalone, more than likely the microtech ecu. 10:5:1 High Compression Pistons, forged rods, titanium valve springs and retainers, that nice and pretty cosworth intake manifold and maybe port match the intake ports since the head ports have already been matched to the header.

If I have any more cash leftover after that and I'm not struggling I'll go with an over sized valve job. Other than that it should set me around 200 - 250 hp depending on harshness of cams, valves and tune

[rynosilver3]

im going turbo 8 psi 3 inch exhaust hoping for 250 hp but thats not until my warrenty is up i figure a year and a half at the most should give me enough time to save the money and well i crossed 25k today 1/2 way there

[droptopman]

8 psi... WEAK. im glad my motor was built for boost... id be making at least 8 psi on the smallest turbo i am looking at... the bigger ones closer to 18 psi. most likely around a nice, safe 15 though... until someday it breaks so i can build it better and stronger... then up into the low 20's. got to love motors that were designed for turbos. oh, and 15 would be on the stock internals... and at 15 psi, i should get near 250 hp, maybe a little higher.