Ok- I read the post on the swap. I put in a 350 out of a 1991 Chevy van into a 1991 Camaro. Will the 305 ecm not let the motor start? Will the 727 ecm out of the van work? The motor will start with some popping and will only run at 3/4 throttle. Thanks

 

Need more details on the engine swap - I'm sure the 350 from the van is a TBI. Was the Camaro also a TBI unit?
If you did no tuning to the computer, the fuel injectors are not being pulsed for long enough to supply enough fuel to a 350 (since the ECM thinks it's only a 305).
The 727 ECM harness from the Van would definitely work (if it did before pulling the engine), but the Camaro harness would need to be changed - lots of re-pinning to do.

 

Both were indeed TBI. I did get it running, but it didn't run well.
When I swapped motors, I kept the 350 knock sensor and the injectors. All the other sensors I transferred from the 305 to the 350.
I decided to take a chance and plug in the 727 ECM, and it definitely ran better- much better. Has a high idle, but it runs smoother and has some power.
Where is this "chip" in the ECM and how does one remove it. Could I use the chip out of the 727 and put it in the 746? I can't seem to find any info on swapping chips, but the thread on 305/350 swaps said I would have to do it.
Thanks

 

Frankly, I'm a bit confused - how were you able to plug in the 727 from the van into the 1991 Camaro so quickly? Aren't the ECM harness plugs significantly different? Are you sure the Van ECM was a 727?

As for swapping the chips, see:

 

The harnesses were identical. The number on the ecm ended in 727, maybe it's 747, it is from a 1991 van. It has more "*****" with the van ecm, but overall it doesn't run as well. Tomorrow I may get to the U-Pull-It they had several Caprices there.
I also need to check the codes and check the sensors, as well as address the oil leak.
We are getting into harvest so I don't get a lot of time .
PS- thanks for the info on the chip- I may be doing that soon!

 

Its not going to run as well in the Camaro as it did in the van unless you do something about the Camaro's horrendously horrible exhaust manifolds, y-pipe and restrictive exhaust system.

The Caprice ECM is not really going to help you unless you can find a cop car with the larger injectors and matching 8746 chip.

You can however advance the timing to 4-6*BTDC and bring some torque to the 350. Might also check the fuel pressure. Many stock regulators are in the 9-10.5 psi range and even a stock engine will want 12-13 psi.

You should also have grabbed the ESC module under the seat next to the ECM for the 350 van.

The 91 van should have a 1227747 ECM if it had a 700r4 transmission. Some really late 91s might have had the 92 only 299 ecm.

 

Fast 355- I can still grab the ESC, the van is still in my yard where will it plug into the Camaro?
I do have the base timing set at 6* BTDC.
Where do I check fuel pressure, at the TB?
Yes, the van has the 7747 ECM.
Thanks for the help!

 

I forget where it is year to year and vehicle to vehicle, but IIRC on a TBI F-car it is near the MAP sensor on the firewall. The other F-car I looked at recently was a 87 LG4 car and it was on the firewall, behind the strut tower on the driverside very near the baro sensor.

TBI does not have a shrader valve in stock form, I use an Actron kit I bought at Autozone and it connects at the back of the TBI.

 

OK I have the Autozone tester, I will get it on.
I will also pull the ESC and find the plug- can't be rocket science
Thanks again!

 

Ok- swaped the ESC (hidden behind the drivers captain chair of the van lol) , swapped the TPS- the other one was reading 4.52 at rest, new one is in spec., swapped the IAC- the one on the 350 was yucky, the other one looked good. Now it starts and idles, fairly smooth, too. Has a sort of lope after it gets to operating temp, but all together is sounding much better.
Thanks a bunch- it might live
Oh- and no CEL have a MAT sensor code but it doesn't kick the light, I can live wit that!!