hi i just did the 305 tbi to a goodwrench 350 tbi. i got a new chip tbichips and a knock sensor for the 350 that was on it all ready.new 350 injectors. i got the engine to start and runs good then after 5 min it runs like crap and stalls. timming is way advance cant get it right. my question is do i need a new esc, electronic spark controle moduler? i read that i do and i also was told i dont. can any one help me and which one if i do need one. thanks alot

A 350 ESC Module is important to get. You are right, some say it doesn't matter, but in my opinion it does matter. Ask Brian for sure, but I know he will agree.

I do understand the point others make because part # 16128251 is used in 4.3L and 5.7L vehicles. Makes no sense does it?

Part # 16128261 is for the 5.7L vehicles only.

Let me know what Brian has to say

thanks so much for the info. i just sent brian a email. i just put back my old 305 chip and started right up and then checked the timming and it was pretty close. so that tells me the esc is a must because the 305 esc does not even come close to the timming marks with the 350 chip. i need the 350 esc. thanks alot. it stinks that they are so much money. do you have any idea what the timming should be? should it be set to 0 like the 305? thanks

5.0L (VINS E & F) & 5.7L (VINS 7 & 8)
1. Place transmission in Park. Start and warm engine to normal operating temperature. Turn A/C and all accessories off. Ensure CHECK ENGINE light is off.
2. Put Electronic Spark Timing (EST) into by-pass mode by unplugging Set-Timing connector. Connector is a single wire in wiring harness near distributor or right shock tower. DO NOT unplug 4-wire connector at distributor.
3. Connect timing light to spark plug No. 1 wire. Loosen distributor hold-down bolt. Set timing to specification. Refer to the V8 IGNITION TIMING SPECIFICATIONS below. Tighten distributor, and recheck timing. Reconnect Set-Timing connector. Clear Electronic Control Module (ECM) trouble code by momentarily disconnecting ECM power source or negative battery terminal.

Application Degrees BTDC @ RPM
5.0L 0deg @ 600
5.7L
VIN 7 0deg @ ( 2)

VIN 8 6deg @ 600

( 2) A/T in Drive.

This is by far the best way to set timing on these vehicles.

thanks for the great info. i just got to buy a esc then i can do the timming. thanks so much.

I've got them for $45

The ESC module has nothing to do with the timing issues you are reporting. What does a scan tool report for knock counts?

As far as the base distributor timing, that is up to the chip tuner. He can make it whatever he wants. So you need to ask him what the distributor base timing is to be set to.

For a 350 ESC module hit a U-Pull-It yard. Cost $5 - $10 bucks at the most. Can be found in a ton of full size vans under the drivers seat. Pickups under the hood, and so on. HKR is what you want.

RBob.

Yes, that is correct. Brian almost always sets it for stock that is why i posted what I did.

i just got my new esc today and the engine sounds alot better but i just cant get it timmed right. i am doing everything right but i cant get it timmed in the timming numbers on the tab. if i do it will stall. i can see the timming line its right before the tab. the car has no power and runs a little rough. any idea? thanks for everything. i am waiting on an email back from brian.

Are you using a set back timing light? If not, try using one and slowly rotating the dial until you see your timing mark on the balancer at the Zero mark on the tab. Look at the timing light scale and see how many degrees the light says you have. That number should agree with whatever timing light you have been using. Example: the light you are using says you can't get any closer than 15 degrees advanced....switch to a set back light and rotate the dial to 15 degrees and your timing line and tab should line up at Zero. Sometimes timing tabs get bent or are not correct for the balancer/application. Just some thoughts. Good Luck!
Craig

thanks for the info. iam using a sears timming light its just a regular light. i bought a new knock sensor (gm-10456288) today the old one was pretty nasty looking with oil caked all over it. the engine seems alot smoother and i was able to get the timming lower. i have it around 6 right now but i havent test drive it yet. but its definitley alot smoother.

just to let everybody know i got my engine running a few days ago i did the 305tbi to 350tbi swap with a good wrench engine and its running awesome. i had a little trouble. it was running a little rough but checked the wires on the cap and i had a wire wrong and now the engine runs nice. i am still not 100 percent what the timming should be set at i have it around 6 and it seems to be fine. i can smoke them up anytime i love it. my 305 oil pressure sender does not fit and the 350 one is only a two prong and my wire is a three prong so i dont know what the oil pressure is but i did take a valve cover off and it all looks great. my transmision is not shifting as hard as it use to. i check the cable and it looks good. i bought all 350 sensors like the esc,knock sensor and a custom chip from tbichips and 350 injectors. thanks for all the help.

Anthony- You sound pretty happy with the results. Which Goodwrench 350 did you go with? Do you have the part number? I'm looking to do the same swap soon.

Your stock OPSU is designed to insert in the block just above the oil filter. There should be a place in the new motor for it.

But - if that doesn't work ...

On the china wall, at rear of intake, there is a small hole (will have a plug in it I assume). You can buy brass fittings/elbows at any local hardware store to come up, and turn to the side, and connect a oil pressure sending unit from like a 1985 car to that location. Your looking for a 1 wire OPSU with a single spade terminal on it that is for a car with gauges (not idiot lights).

Then, you can extend the small wire from your 3-wire factory OPSU up to that location. That will feed your gauge the info for it to work.

The other 2 wires on your factory OPSU are for the fuel pump back-up circuit - in the event that the ECM or fuel pump relay goes bad, oil pressure will make that OPSU directly run the fuel pump off the battery. So it's not critical for that circuit to be connected anywhere - just carry an extra fuel pump relay with you just in case.

There will be a fuse tucked behind the battery at the fender, in a small weatherpack. Remove that fuse, so that there's never a risk of those OPSU wires ever shorting out anywhere and causing a fire (removing the fuse will kill that circuit).

OR - if you want to keep that backup circuit intact, then extend all 3 wires from your factory OPSU up to that china wall location, and use the right brass fittings/elbows to get your factory 3-wire OPSU connected at that china wall location.