ok i have switched everything needed to go from tbi to carb. but im having some issues here they are maybe someone could help

1.its been almost imposible to time the engine i try to go by the tab and when i think its running the best im at really low RPMs on the tach. i have heard that i deling is suppost to be at arround 8k mine is arround 5k

* im running a accel dizzy by the way it came on my 80 305 sbc

2. motor shakes alot and feels like it strugles to go at first, i have a fuel pressure gauge on the line and they needle just bounces non stop.

i have heard that on 87 and up wit center bolt heads if you witch to carb you must fun hi octane gas like 92 oct is this right? i usually out 87 oct could the gas be causing this problem?

and if i want to change the heads to older style non center bolt what do i have to replace other than the heads them selfs


thanks in advance

 

well i just did the same swap on my 83. did you swap to a non computer controlled carb and leave the ecm plugged in?

 

i put a edelbrock 600cfm manual choke

 

'87 TBI? Are you sure about that? TBI wasn't introduced until 1988.

No, you don't need to change to 92 octane because you put a carb on an EFI engine. Pure poppycock.

What fuel pressure are you observing? Did you put in a return-style regulator?

8k and 5k what while setting the timing? Are you disconnecting the vacuum advance when you set the timing?

 

its tpi, there is no regulator the line come straight out the pump to the carb on the carb line there is a fuel pressure gauge, and i tryed timming it wit the vac adc disconected and wit it connected, ive also heard that it could be the distribuitor?

 

If you are running the stock electric in-tank fuel pump, you need a return-style regulator to drop the pressure going to the carb.

If you are not running the stock electric in-tank fuel pump, you need to remove it. There is a sticky in the top section of this forum detailing how to turn an in-tank electric pump pick-up into a mechanical style pick-up.

Does the Accel distributor have vacuum and centrifugal advance?

 

i know it has a vacumm advance but im not sure about centrifugal advance, how can you tell?

 

If it has vacuum advance, it has centrifugal advance (also know as "mechanical" advance). The advance weights & springs are (usually) under the rotor.

 

so yes it thoes, so wat should i do?

 

Set the timing at idle with the vacuum advance disconnected and plugged to about 12 degrees BTDC.

Still waiting to hear about the fuel pump.

 

the fuel pump is a mechanical one and im running a fuel cell in the trunk

 

bump