Questions about ignition and ECU

[1988Stang]

hey there I have a 1988 GT hatch with a rebuilt 302 stroked to a 347 with GT-40 aluminum heads 64cc combustion chamber, comp. cam .55/.55 lift 270/270 duration, flat top KB hypertechnic pistons with a floating wrist pin, eagle forged steel crank, eagle H-beam rods, ARP rod bolts, ARP heads studs, Gt-40 intake, all stainless steel custom headers straight piped to Bassaini Mufflers, rebuilt AOD with bigger valve bodies, pump, tranny cooler, TCI aggressive shift kit, and a heavy duty OD band. About 9.5/1 compression.

My question is I cant run the timing above 10 BTDC and wondering if a new ignition will help and which one would best fit my application, also do you think it needs to be switched over to mass air, and if so will my 19# injectors handle the load.

any help with this would be grateful

Thanks
Justin

 

[jrichker]

The 19 Lb injecxtors are too small for a 347 stroker. You need 24 Lb injectors and a minimum of a 112 LPH fuel pump. On the fuel pump, you can use up to a 255 LPH pump with no problems.

The stock ignition is OK for engines without NO2 or pressurized induction up to 400 HP.

What happens when you run more than 10 degrees advance?

 

[1988Stang]

When i go above 10 degrees it seems like its start to ping and miss. do you think its the injectors? Also would a Mass Air Conversion help.

 

[JBeezy53]

Seems like you have a lot invested in that engine, why didn't you put a little more in and get forged pistons?

 

[jrichker]

When i go above 10 degrees it seems like its start to ping and miss. do you think its the injectors? Also would a Mass Air Conversion help.

With all you have done to increase the airflow through the engine, the stock computer tune isn't going to work. You will need either a custom chip or a Mass Air conversion.

With a custom chip, everytime you change the engine's airflow by a different cam, heads or intake, you need to get the chip re-burned to re-calibrate the computer's Air/Fuel tables & ignition advance curve.

Mass Air with 24 LB injectors & matching 24 LB calibrated MAF is the best choice. Right now you are probably running on the lean side, which will increase the tendency to ping and miss. Don't forget to upgrade the fuel pump to at least 112 LPH for match the injectors. You can go larger than 112 LPH on the fuel pump and the fuel pressure regulator will compensate for the extra fuel.

 

[1988Stang]

Well thank you guys for the help. i dont know that much when it comes to the computer end of it. I planned on a mass air conversion but just didnt how badly it needed it.

also the resason i put hypertechnic pistons in it is because i dont plan on putting on a power adder any time soon and didnt want to be tempted. later though im going to bulid a 302 with vortech supercharger when i do that i want a block, pistons, crank etc... that i know will take the abuse.