I recently swapped in a 350tpi, its broken in and then took it for a few WOT runs. It pulled decent, then threw a code 42, after that it would hit a brick wall around 2500-3000 rpm. I let it cool down, took it out again, great power, then throws the code and it falls on its face. driving it normal, letting it shift around 2k it has great low end

I still have the stock 305 7165 computer, I have the 350 knock sensor and module, 24lb injectors. A mild cam .459lift 270 duration 112*lobe 46*over lap. 1500-5500rpm



As for the timing, if i set it to 6*btdc the engine loves it, i can even take it up to 20 initial and it loves it. as soon as i connect the ESC wire it will start to surge nasty. at 6* it will surge, so what i did was throw it in drive, and retarded the timing till the engine didnt pull as much. so its probably running around 0*


The overview is:

1)What can i do to stop the surging?(with the correct timing)
2)what can i do about hitting a wall at 3k?

 

well....are you getting a code 42 with 20 degrees of timing.....that's too much timing. your are setting it according to factory specs...unplugging single wire connector on passenger side engine bay?? I bet the knock sensor is picking up a ping from too much timing.....OR how did you install the knock sensor??? they are supposed to be put into block at something very light, like 18 foot pounds of torque....if you put it on there too tight it might and probably will affect it as well.....either way your not going over 3K because of computer retarding timing to 'save' motor.
The other thing....wrong computer...you need to have it burned or geta a 350 computer of same year, or something. You have bigger injectors, more cubes, and a bigger cam.....that's something that needs to be taken care of too....one of the computer guys should be able to help you better with that....I send mine off to PCMforLESS.com but a lot of guys in here do their own and would know what to do for sure.....but it is an issue.
hhope that helped some....

 

Thanks! when i set the timing it is with the connector unplugged. no pinging occurs till about 25*. at 20* the engine roars when revved. the stock timing is 6* which even though its set at that, once i plug the connector back the idle surges. 1200rpm-500 and sometimes it will die. the surging goes away if i back off the timing. the only way i can drive it is when the timing is retarded alot


as for the computer, i know a great tune will work wonders but the thing is Im broke, the reason i built this engine was to have a DD to college. about a 50min drive one way. i just want to see if there is anyway to make it drivable till i have money to get a chip burned

 

the knock sensor is fine, with it connected or unplugged it does the same thing. im sure there is no pinging, especially with the timing retarded so much for the car to not surge.

when set to 6* the car is not drivable due to the surging, so i backed it off (retarded) till its drivable

 

bump. any computer tuners around the riverside area?

 

also my car has no vacuum (Due to the cam) would that have a role in the computer not being able to run the car?

I reset the computer overnight, set the base timing at 6* plug the EST connector in and it ran. sounded smooth but had no power. i noticed that when the EST plugged in, the computer removes(retards) the timing. is this supposed to happen? I set it to 25* idle with the EST connected... then i slowly revved it and about 2000rpm the timing had dropped to about 10*total is that normal?

 

I would suspect your problem lies with the computer ....aftermarket stuff on a computer designed for a stock 305......I used pcmforless.com and have had great success with them.....look up their website and give them a call....it takes a day or two to get back to ya with quesitons....call him up and ask what he thinks about it......email them at Alvin@pcmforless.com or call
number is (704)-307-4227

 

Thanks! Though it states off road use only, and knowing california smog laws thats not much of a good thing. Ill give it a shot though and see what he says