Hey all Im just wondering if anyone can tell me what the stock chip fuel and timing limit is on a 7747 ecm?? I dont have my ebl yet but it would seem that everything is done by about 4000 to 4500 rpm. Would this be a safe assumption??? My current 350 set up is a standard bore 350 with 8.75 compresion 461 heads/ultimate tbi mods/AFPR/Edelbrock RPM air-gap manifold and a comp 260h cam. Spec are 440 lift int@exh with 212 Int/exh duration on 110lsa. Ive got it running fairly well on a stock tune. Im a little high on fuel pressure and have to have it advanced to 8 degrees BTDC. It Has just a slight of idle hesitation and pulls decent until about 4200rpm. Just wondering if the stock tune is all done by then??? Any Help on this subject would be very appreciated. I cant wait for the EBL!!!

 

Unfortunatly it's not that easy of a question to answer. A certain tune won't just be "done" by a particular rpm. You can have a tune that won't run for crap under 3000 rpm but run fine up top or vise versa.

To put it midly your combo should run like absolute poo. Just a guess but I bet you are way rich down low with the cam and added fuel pressure, then about right in the mid range and then going quickly lean in the top end. Just a guess. This is just the fuel side of things, timing is totally different animal and as you found your motor requires a LOT more timing to idle properly, the problem is that now you probably have way too much timing up top and are getting into knock retard. I don't suggest ANY wide open throttle runs untill you can properly tune the car.

Keep in mind you don't have to have the EBL to tune, you are still going to need a burned with the EBL so I would go ahead and get the Burn1 for 85$ and get busy properly tuning your ECM. Once you have the money you can step up to the EBL system.

 

Hey thanks for the reply BMmonte!! I know that its way out of tune just by the loss of power I have compared to when I broke it in on a carb. And I would tend to agree with you about my timing and fuel curves. But it is totally drivable right now, but like you say I do have to stay out of it. Its drives decent at part throttle so that will have to do for now. If I have to spend about $200 for a burn1 and the rest of the equipment/zif socket/chip socket/chips/ etc. I figure why not spend the $230 for the EBL and just order the burn1 and some chips to go with it and then I should be done right??? Any advice on where to start tuning or what to tune first would also be Greatly appreciated. Thanks