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Russell · 09-29-2007, 08:34 PM

As mentioned above you'll need to get ahold of a set of 350 injectors, a 350 knock sensor, ESC module, and a 350 prom.

The prom is located inside the engine computer behind the glove box. Just take the two screws out of the cover, pop it off, and replace the two chips inside. Make sure that you put the two chips in properly with the right orientation or you'll have problems.

350 knock sensor threads in directly where the old one was, and uses the same connector. You are best off buying a brand new one from GM, as they begin to loose their sensitivity with time, and most of the aftermarket units from Napa or whatever are junk. Make sure you install the new one by hand, and not with a power tool of some sort, the force of an impact or something will most likely wreck it.

ESC module is located just to the left of the throttlebody as the big square / flat module. These are tuned to the specific frequencies of the knock sensor output vs engine displacement, so make sure you get the right one unless you want to chase your tail looking for ignition issues or a code 42. Again, best off buying new from GM, as they can be tough to identify from different vehicles in the wrecking yard, and like usual, the aftermarket units suck.

350 injectors can be found on any TBI 350 engine from either a truck or a car and changing them out is pretty easy. Before you install your new gasket and stuff, run the engine for a couple minutes with the new injectors and use a timing light to see where the fuel spray is hitting the side of the throttle body bores. You want it to be hitting the side right above the butterfly valves on the baseplate to get your best atomization. Quite often they hit the valves making big droplets that are hard to burn, so it may help you a bunch to install an injector pod spacer. Be careful when you re-tighten the pod as it is fragile, and you can bust the rear foot off really easy.

TBI units also benefit a bunch from a throttlebody spacer between the TBI unit and the intake, just like a carb. Open air elements help a ton with airflow capabilities too

If you want a couple other quick / free power-gains for TBI engines, check out the Ultimate TBI articles at http://www.thirdgen.org/technical-articles

09-29-2007, 08:34 PM	#6
Russell Professional Grade Join Date: May 2003 Location: Fort McMurray, Alberta Posts: 7,915	Re: new 350 TBI As mentioned above you'll need to get ahold of a set of 350 injectors, a 350 knock sensor, ESC module, and a 350 prom. The prom is located inside the engine computer behind the glove box. Just take the two screws out of the cover, pop it off, and replace the two chips inside. Make sure that you put the two chips in properly with the right orientation or you'll have problems. 350 knock sensor threads in directly where the old one was, and uses the same connector. You are best off buying a brand new one from GM, as they begin to loose their sensitivity with time, and most of the aftermarket units from Napa or whatever are junk. Make sure you install the new one by hand, and not with a power tool of some sort, the force of an impact or something will most likely wreck it. ESC module is located just to the left of the throttlebody as the big square / flat module. These are tuned to the specific frequencies of the knock sensor output vs engine displacement, so make sure you get the right one unless you want to chase your tail looking for ignition issues or a code 42. Again, best off buying new from GM, as they can be tough to identify from different vehicles in the wrecking yard, and like usual, the aftermarket units suck. 350 injectors can be found on any TBI 350 engine from either a truck or a car and changing them out is pretty easy. Before you install your new gasket and stuff, run the engine for a couple minutes with the new injectors and use a timing light to see where the fuel spray is hitting the side of the throttle body bores. You want it to be hitting the side right above the butterfly valves on the baseplate to get your best atomization. Quite often they hit the valves making big droplets that are hard to burn, so it may help you a bunch to install an injector pod spacer. Be careful when you re-tighten the pod as it is fragile, and you can bust the rear foot off really easy. TBI units also benefit a bunch from a throttlebody spacer between the TBI unit and the intake, just like a carb. Open air elements help a ton with airflow capabilities too If you want a couple other quick / free power-gains for TBI engines, check out the Ultimate TBI articles at http://www.thirdgen.org/technical-articles __________________ 1995 Chevrolet 2 Door Tahoe (6.6L LBZ Duramax / ZF6 / NP241 with 1 ton solid axle swap)