hi every one! i have a 91 tbi bird and i am swapping to a 350 .030 over 4 bolt 2 piece rear with vortec heads. my concern is keeping my gauges working properly. it is a non egr set up currently in another 3rd gen. i have looked and looked for info on this and am either blind or looked right past it i have been studyin' the wire diagram but it won't show the in's and out's of my ecm. all i need is the gauges to work, i can yank the S.E.S light no prob. can this be done?

 

Welcome aboard thirdgen.org.

This doesn't sound like a Pontiac engine, but rather a 350 SBC going into to a Pontiac body, so I moved it out of the Pontiac engine swap thread.

The simple answer to your question is the gauge signals don't go through the ECM. So, disabling or removing the ECM doesn't affect the gauges.

 

what about the speedometer? i know i have a VSS buffer, how will i maintain the speedo? i thank you for you info, i have only just began to get into building my car. i bought it nov. 08 showed it at Lowes motor speedways Auto Fair twice and came home with 3 best daily driver awards. just time to step up the power!

 

The VSS feeds into the ECM, but the ECM does not feed the speedometer. So, just leave the buffer in there, and it should work (assuming you keep the VSS on the tranny).

You could run this with TBI and not have to give up the benefits of EFI. The lack of EGR with the Vortec heads means it won't be emissions legal, but it'll run fine. You weren't specific about the induction you intended to use, but since you were talking like the ECM wasn't going to be used, it sounded like you were intending to go with a carb. EFI would be better for a daily driver.

By the way, if you keep the ECM in there, it will continue to operate the in-tank electric fuel pump.

 

so to stay tbi i would have to put a new chip in the ecm and get a vortec specific tbi intake? i want the car to have way more power then the lo3, i am not to worried about emissions, i know a guy that don't look i would like the car to be reliable and driver friendly. it has a holley 650 i belive non choke.

 

There is a sticky in the TBI forum called "Budget TBI Buildup". It takes a 350 Vortec engine and modifies it for TBI power. You could do similarly.

A 350 TBI would be a lot more driver-friendly than a chokeless carb.

I think you'd be much happier in the end going through the TBI process.

 

the block is early 80s 2 piece will it work? the block is .030 over running 10.5:1 flat toppers, comp cams xe267h, ported/polished vortecs and rpm air gap. will this be ecm friendly?

 

You won't be able to use the roller cams talked about in the TBI sticky.

"XE267h"? Or, XE268H? The Xtreme Energy 268H is computer-friendly, typically with custom tuning for speed density, but it's a relative mild cam.

The RPM would work with a squarebore to TBI adapter.

 

its a 268h.
i have been searching and reading alot on this whole subject and as long as i get more power per dollar with the carb vs. the ecm tbi set up, i think i will go with the carb. it has a better performing in cap hei by msd in it as well.. i am just wanting to plan it out before i get there so i know what to expect. i have no worries about emissions(already illegal) so i just need to get the best fuel deivery figured out for this setup. i am thinking about running the factory intank pump to a mallory afps. will this support a 350+hp engine? my other dilema is money being tight. i looked at what it will take to build the tbi system up to run and is pretty pricey. i may start a new thread when i beguin my build. but i really thank you for your advice. i hope to get the donor car this saturday. so new thread sunday for the swap.

 

According to the TBI guys, the stock TBI electric pump is only good for a couple hundred HP. So, you'll probably have to upgrade to at least a TPI pump, or while you're at it, might as well be a Walbro.

 

is that for staying tbi or converting to carb? if its for the carb then i might as well go with the summit fuel pump kit for carbs. i dont see where the fuel pump i have will be insuficent to run a holley 650. but again i am new to the whole thing