Hello all,
This is my first post, and I am in search of information regarding ignition/exhaust upgrades for the 4.9L. More specifficaly the engine is in a 1977 F 150 with a Dura Spark ingnition. The truck has retained it's origional engine. I checked out the DUI and upgraded Dura Spark ingnition systems. Do either of the above listed ignition compnents really provide a noticeable differance? Is there any other options? I also read an article about igniton upgrades on the cheap, but I would rather purchase a complete and reputable system.

I am currently finishing up an overhall on my truck, including .30 over pistons, new crank and rod bearings, ground crankshaft, RV1 cam (which did not include lift and duration specs), Offenhauser intake, Edelbrock 500cfm carb, 8mm plug wires, and an Edelbrock 14" air cleaner. I have decided to use the stock exhaust for now, since I have not found anyhting I like. I do not want my truck to sound like a rice grinder. Any suggestions on the exhaust would be apperciated. I know the intake and exhaust manifolds bolt together, and I am not sure how well that would work with headers or EFI manifolds.

The truck itself was purchased by my grandfather, and has been in our family ever since. My goal is to make a fuctional and reliable combination. The truck has received a six inch suspension lift, 35" tires, all new steering componets and many new interior parts. The truck is far from being complete, but really, what project is ever complete? This is a nice truck and I hope to keep it in the family, hopefully passing it on to my children to enjoy as much as I do.

Thank you for taking the time to read this post, I look forward to your responses. I have read many posts and am suprised by the assistance and adivce people take the time to post. Thanks to all for the great reading and sharing a great hobby.

Sincerely,


Ford Couple99

 

I ended up using a stock DSII (blue) module on mine. From what I understand, the aftermarket ones only really gain you performance at upper rpms. I also have a Blaster 2 coil and accel wires. My timing is set at 7-8 btdc. It starts pretty well cold, and when warm, it fires immediately.

As far as exhaust, I have some unknown headers with dual 2.5" pipes with turbo mufflers. It sounds good, but ricey at 4K.

One thing you didn't mention is gears. From my experience, don't gear too low. The 300 is a chugger, not a revver, so stick on the high side of gearing. I used to have 3.73s w/33s, and now have 4.10s w/36s. I would say run 3.50s (most likely stock) with your tires, or 3.73s. Much lower, and the engine seems to not perform as good.

Good luck! and post some pics up when you can.

 

Stock exhaust manifold works with an Offy Intake Manifold. EFI manifolds or headers work too. If you go with EFI manifolds or headers it is best to have some heat going to the base of the OFFY intake or use a water heated carb spacer from a 60's something Ford.

When it comes to ignition the combinations are many...usually a matter of preference but performance gains are noticeable.

 

Thanks for the suggestions, I will post pics soon.

 

I am running a Hedman header on my 84, I am very happy with the performance. I am going to redo the exhaust (among many other things, the truck getting a frame off) The Hedman has dual collectors, I am going to Y them into a single 3" with some kind of muffler to cancel out the raspiness.