CALLING ALL TBI GURU's

tcfco2005 · #1 02-21-2006, 01:07 PM

I have a 383 motor that im throwing in my car...Right now i have a 305tbi in it.
The desktopdyno said it should be making around 450-475 hp so most likely its only about 400-425 hp...the engines rpm redline will be around 6000rpm's The heads on the 383 are Dart Pro 1 heads. 200 CC intake runners, 72 CC chambers and 2.02 1.60 valves...
so what i need to know is what intake do yall think i should run and will a 454 TBI unit be enough to feed this thing or will i need to get it ported..I know i will need bigger injectors than the 454's stock ones.What exactly is the flow for tbi's...by flow i mean like on a tpi they fall on there face at upper rpms, so what about the tbi..I will also have to buy all of the chip burning things but thats another story.

Nate355RS · #2 02-21-2006, 04:24 PM

Your going to be right on the very edge of what TBI can do, and probably a little bit over it if you make what the desktop dyno says. Cause TBI only has two injectors it's power potential is limit compared to multiport, just get the biggest injectors you can find and hope it's enough.

97cavalier · #3 02-21-2006, 04:33 PM

the 454 injectors should do and bore the 454 intake a little bigger. should be a monster after that.

Nate355RS · #4 02-21-2006, 11:55 PM

I reread your post and I missed a couple things. TBI can support 400-425 easily if set up right. I believe with 2 90pph injetors the max power you could possibly make would be 450-460hp, and as long as it's tuned right and given enough fuel, TBI won't have the same struggles up top as TPI. I've never tried to tune a 400hp TBI so I don't know how hard it would be, but I can imagine it would be a nightmare compared to my 305. It would be a good idea to let an expert handle it cause it'll take many many many hours to learn how to tune that beast. I think 400hp is plenty to get deep into the 12's

Savage Messiah · #5 02-22-2006, 12:55 AM

Why not switch to fuel injection?

tcfco2005 · #6 02-22-2006, 01:08 AM

Quote:

Originally Posted by Savage Messiah

Why not switch to fuel injection?

TBI is FI

Thanks for the help Nate305rs...ive been reading up on eprom and burning your own chips and all that good stuff over at thirdgen.org and im buying all the equipment next week...im going to just practice with my 305 right now just to learn how to do it...And nate are you also saying that the tbi has a higher rpm range that the tpi cause thats what i thought but i couldnt find it anywhere...?

Genopsyde · #7 02-22-2006, 07:32 AM

you'll need to change the fuel pump also, the stock TBI one is a low pressure pump.

tcfco2005 · #8 02-22-2006, 10:29 AM

ya i was going to throw in a tpi fuel pump..and will i need to get a fuel pressure regulator or will the jet tbi regular be enough?

Nate355RS · #9 02-22-2006, 11:22 AM

It says that the Jet regulator is good up to 20 psi, if your going to push 400, depending on your injectors, you should have to be around 25 psi maybe a little less or more.

Savage Messiah · #10 02-22-2006, 08:08 PM

ok, then change that to a more efficient fuel injection

Nate355RS · #11 02-22-2006, 09:14 PM

454 tbi and 90pph incetors cost MUCH less than "more efficient fuel injection", all you have to do is use the brain on top of your shoulders to figure it out and tune it. Even if you can't quite get the hang of it, pay someone to do it and you'll still be less than the cost of multiport. So I guess the more cost "efficient" FI would be TBI. Also EBL will be coming around soon and its baud rate will rival if not beat modern ecu's plus it'll pretty much tune your set up for you.

tcfco2005 · #12 02-22-2006, 10:18 PM

ya thats the main reason im sticking with tbi...cause its cheaper....less stuff for me to buy and change..
And whats this EBL stuff and how long till it comes out...i like the sound of it already...

Genopsyde · #13 02-22-2006, 10:26 PM

that's why i'm sticking with TBI as well, it's a lot easier and cost a lot less. I'm starting with the holley 670 which is just a bit bigger than the 454, and I think it has 75lb injectors. I won't move up to the 90lb until after I change to a bigger fuel pump.

Nate355RS · #14 02-22-2006, 10:32 PM

Got no clue when Embedded Lockers, HUD, and the Ultimate TBI code (EBL) will be finished and ready for sale but here is the jist of it, it's a little technical starting off but it gets easier to understand as the thread goes on. http://thirdgen.org/techbb2/showthre...hreadid=321767

Genopsyde · #15 02-22-2006, 10:57 PM

that's just too much reading for me right now.

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