im swapping out my 305 for the GM 350 330/HO. I was told by Brian at tbichips that to keep my tbi i could get the gm vortec tbi intake manifold, and keep my throttle body that i have now and just swap the 2 injectors to the 80lb ones GM made with the 454s, that and change the fuel pump. Has anybody gone this route, and if not does any body have any other suggestoins. i definitely want to keep my tbi and i know i will have to change the fuel pump

I don't see the stock tb flowing the cfm to support 330hp. A 46mm unit would be a better unit, maybe even a 50mm, depending on the VE of your engine. Here's a calculator that should help you figure it out.
http://www.wallaceracing.com/intakecfm.php

You should also look into an external fuel pressure regulator in addition to the pump. Someone else can report the max pressures they have gotten out of the stock unit, but I don't think it's much more than 14-14.5psi. I ran some calculations for a 383 with a few less hp than your ho and figured I would need 16psi on 80lb injectors to feed it properly.

I don't have the knowledge that most of the members have here, but I've spent a couple hundred hours researching the subject. I'm curious what the senior members have to add.

well thats what i was told, just to keep the stock throttle body on my 305, but take the injectors and replace them with the 80lb ones from the 454.

does anyone else know if that would be enough to feed the GM 350 330/H0
with a walbro 255 fuel pump?

Last fall I installed a 350 H.O in my 85 Camaro that had a 305 TBI in it. I used the suggestions from Brian at TBI Chips but never got it running right with the eighty pound injectors with a Hi-Pro Fuel Pump and Fuel Pressure Regulator and a modified Thottle Body from CFM. I didn't know how to burn my own chips was the big problem and had Brian burn about 3 chips after numerous datalogs. It was either to lean or to rich. I switched to a Carb setup and its been running fine since. Someone I met at a car cruise did the 350 H.O. with the TBI and he said his 89 TransAm was running fine. Don't know who burned a chip for him but here what he said is his setup.

Modified Thottle Body from CFM.
350 Police Injectors used in 92/93 Caprice (64 lb, I believe).
350 Electronic Control Module
350 Knock Sensor
3 wire O2 Sensor in driver side header collector
Fuel Pressure Regulator and Gauge
Will need a performance exhaust
New Performance Fuel Pump
Note: Check out the stock Distributor Gear and see if it's compatible with the 350 H.O Cam Gear???
Thats about all I remember. But I do know that burning the chip for your setup will be important to get it running right. There are numerous people on this form that can guide you with a lot more information than what I know.
Good Luck

Locks like u need to follow the "budget tbi build up" sticky.
Except the transmission governor thats probably not the correct part # for your transmission (it wasent for mine).

For tuning use EBL.

You might want to look on the cfm-tech website as they claim to have a kit for the 330HO that makes it a no brainer. Look at my post from a few days ago, it has a link to the page on cfm-tech where they talk about it. I am thinking of doing the same thing.

350HO is an awesome motor for the price. i love mine. she'll want stall and gears for sure though, and lots of traction.

you do have full exhaust already, or waiting to go in correct?


...
with my MPH and weight calculations, I'm making 310FWHP...just ignore the e.t. though lol, i don't get to the track much...

I'm am on my 6th or 7th chip from Brian, I lost count around 4. My engine has idle problems, and loses much power after 4500rpm, Im swapping to a carb this spring.

I am currently running a 350 putting out about 340hp with a 350tbi that has 454 injectors in it. Had a chip burnt from tbichips and the car has been running great. I'm even running the stock fuel pump. Car run's consistent 13.6's on motor.

well i dont get it, it seems like half of you have success with this brian guy from tbi chips, and the rest of you are SOL.

i dont know what to do, i guess it all comes down to tuning, but from what im reading if i just bought a whole new throttle body like the holly 670 cfm, thats only good for 275 HP, so the engine wouldnt run right.

Has anybody got any other ideas to run my throttle body with this GM 350 330 HO

Why not EBL?

Get it approx tuned with EBL and post back what happened. Included with EBL, you also get your courrent tune, transformed into a EBL bin you can load, to start with.

you mean EBL to tune it, after i get a chip from tbi chips, or can you make your own chips with ebl.

Hey guys I am running a Vortec 350 in my '92 S10 with a 5spd. The motor is a stock longblock, GMPP Vortec to TBI intake, MSD distributer & coil, shorty headers with full 2 1/2 exhaust. I call TBIchips.com and told him about my truck, it was running at the time with everything on it from the factory 4.3 V6, it was just a little lean. Brian told me to do one of two things 1) Change to a tpi or walbro pump, adj pfr, and 350 injectors along with one of his chips. 2) Change nothing other then put in a set of 454 injectors and one of his chips. I had a 454 TBI setting there so I swaped injectors and it runs so good I have never even got around to the chip yet and thats been 10 months and 7K miles ago. Truck starts right up will turn 6K RPMs without any hesatation or boble at all and plugs are burning perfectly. I am planning on getting a little more into it and doing a LT4 HotCam swap and figured I would wait on the chip for that.

Ouch... that GM Vortec Manifold is $310 at Summit! I believe Fast 355 used a Edelbrock 2 barrel Vortec Manifold with TBI unit on top. Not sure what the cost is. Or consider a carb vortec manifold with an adapter plate as well. I think the low profile Weiand single plane is cheap and offerred in Vortec pattern.

I would suggest the 64 lb injectors over the 80's. More resolution provided for AE. Just up the fuel pressure.

No reason why yu cant start tuning with the stock TB. It will make tuning easier for you. If you find it is insufficent easy swap to larger unit with a retune.

Sending datalogs and waiting for a redo from Brian would drive me crazy. I bet many of us have over 100 burns and counting. Lot of variables to deal with.

I have heard good and bad about FastChips (Ed Wright). I talked to him yesterday and he said when I get my truck ready we could schedule a day for me to come up and put the truck on the dyno and it would be right when it leaves his shop. Considering that he is only 4 hours away from me and a decent price I think I am going to do this instead of messing with what seems to be inconsistancy with mail order chips.

No more chips, EBL replaces your slow ECM and garbage chip. You simply load the bins from the laptop to the EBL, takes 1second. There is probably already a EBL bin for someting close to your set up thats just waithing for some VE learns.

Modifications within the bin for your engine requirements are made with tunerpro (free), pretty easy to do and you get excellent support.

I've heard good things about the ebl. I thought about switching to it this summer in preparation for the engine I just swapped in (355 w/ vortec heads, lt4 hot cam, holley tbi, marine tbi to vortec manifold). I'm using the Ostrich from Moates.net and TunerPro RT to tune on the fly. This set-up allows real time tuning, but is limited by the slow ECM and lack of resolution on the fuel and spark tables. So far I've had good success with it, though. I'm still planning on going the EBL route with a wideband to get it perfect sometime down the road.

My recommendation would be a walbro 190 (or 255) with either an external fuel pressure regulator or the 30psi unit that Fast355 recommends with the Ostrich from moates.net. You'll have to buy an adapter to fit the Ostrich's larger "chip", but I think you'll end up saving a little money over the EBL in the end. Actually, now that I think about it, if you have to buy the TunerPro RT software, the total cost might come out pretty close.

If you feel at least a little confident in doing the tuning yourself, I'd steer clear of the mail order chips.

[QUOTEbut I think you'll end up saving a little money over the EBL in the end. Actually, now that I think about it, if you have to buy the TunerPro RT software, the total cost might come out pretty close.

][/quote]
If you have EBL you wont need the TP-RT as the EBL is a datalogging system and well as having ability to create a .bin off the datalog from the datalog if you wish. With Flash option EBL can drop that .bin into ECU. Bingo done. Advantage to Ostrich is that it can be used on various vehicles. I had no need for that so I went with permanent emulator within ECU called Prominator which I will say is similar to FlashEBL. I can always sell ECU to another member here to recover investment if I should buy the 2009 Chev Z28.

do you know if a rochester 454 tbi complete unit, will bolt onto the GM Vortec Tbi intake maniflod without any adapters?

Or am i just better off buying the 350 tbi and using the 454 injectors?

I believe I read a post a few days ago that the GM Vortec needs to be bored to accept 2.00 inch GM 7.4L.

A carb Vortec needs a 2.00 inch adapter plate as well.

From gmPP site:
Manifold With TBI
This aluminum small-block Vortec manifold was designed for maximum horsepower with throttle body fuel injection and EGR usage. The manifold will fit all Vortec design cylinder heads (P/N 12529093, 12558060, 12497186, and 12464298).
Technical Notes: To use EGR, the gasses must be plumbed from the exhaust manifold into the intake manifold. Many exhaust manifolds have drilled and tapped holes that can be used to fabricate a tube. An example is the 1996 and later pickup truck with RPO L31 350 engine, which uses exhaust manifold P/N 12557828, EGR pipe P/N 10220275, and fitting P/N 12552329. That combination will fit this manifold for late model pickup trucks. Vacuum controlled EGR valve P/N 17052693 can be used on some models.

so cfm tech sells a 5.7 throttle body and a 7.4 throttle body both for the same price, and they guy said they will accept gm 80lb injectors since they are sold out of them.
so should i get the 5.7 tb which has 620 cfm, or the 7.4 which has 720 cfm.

5.7 will be easier to tune for sure. But will it be a restriction? Dont know.

what do you mean a restriction?

1 and 11/16 inch T bores may not flow sufficiently to feed that much HP. That is what stock Vette had in 1984 to feed 350 cid 205 HP. But it will be easier to get tuned initially. So going that route might be termporary and later swap in the 7.4L unit after you are gaining experience tuning and sell off the smaller unit. Just a thought.

does anybody know the part numbers for the gm tbi injectors
for the 5.7L cop car (65lb)

and for the 454 (80lb)

im thinking of buying the cfm tech. 5.7 throttle body and putting one of theese injectors on it, to run the GMPP 350 330/HO 330 HP
anybody got any ideas on whcih one i should go with?

It depends on what fuel pressure you are planning on running. If you are only going to bump it up a little (to 15-20psi), you'll have to go with the 80 lb/hr ones to be able to flow enough fuel. If you can bump it up to 30 psi, the 65 lb/hr injectors will be enough. I went with small block injectors at the higher pressure because they are cheaper and more readily available.

so has anyone went with the 5.7 cfm tech throttle body and went with the 454 injectors? how did it work

is this the best way to keep the tbi with that vortec 350 330 HO?

Taken of Z28boy website:

Flow Rating
Application
Color Code
Part Number Markings
GM Part Number

40 PPH
305/5.0 Liter L03, Camaro & Firebird (stock)
Green/White
GM 5235279 *RPD


55 PPH
350/5.7 Liter Pickup
Orange/Black
GM 5235206 *RPD


65 PPH
350/5.7 Liter Cop Car
Yellow/Brown
???
17112412

80 PPH
454/7.4 Liter Big Block Truck - Later Models
Blue/Black
GM 1708430 *RPD
17112560

90 PPH
454/7.4 Liter Big Block Truck
Dark Red/Dark Blue
GM 5235231 *RPD