ok so heres my set up. '86 F-150 4x4 with a manual 4 speed with the granny gear and 31x10.50x15's mud kings. this summer i pulled the 6 and had it bored .30 over and got a master rebuild kit for it and threw in a comp 268-H cam (idling it sounds like a beast ) along with a new clutch and other things. so far im happy with the results but still am looking for more (like everyone else haha). i am noticing it to have a narrow powerband and im about 95% sure that its my advance in my distributor. i would also like to go to a 2 or 4 barrel carb and intake along with throwing on a header to get the most out of my cam. i cringe at the thought of pulling the head again for more mods but for the sake of the build i would do it. in the near future i see a 4 in. lift and 34 in. tires heading my way and considering some axle work. now my questions:

what is a good aftermarket distributor and igniton set up or would i just be better off switching it to a ds2 igniton?
will the 2 or 4 barrel carb be better along with a dual plane or regular intake?
is it difficult to swap in a solid front axle? (i have acces to a danna 44 front and i believe dana 60 rear out of a '79 150 but im no pro at axles and gear ratios so dont hammer me to hard there.)

Im a 19 year old college student so i could say im on a budget but heck i just spent around 2 grand giving an old farm truck a complete makeover so money aint stoppin me!

 

DS2 is very good.

DS2 + gm module is better.

DUI distributors can get you an HEI dizzy (billet shaft, nice, little better than the homemade DS2+ gm module setup but also 3X the price) with custom ignition curve for your cam or a DS2 with custom ignition curve

offenhauser DP with a 390 4bbl should make you happier.

summit still has long tube headers for 140 or so, cant beat that.

that should give you more rpm and a noticable better street performance.

the comp 268 does sound nice at idle.

your typical street port job to the head would help, as would a higher compression ratio but those things are more involved.

 

The bottle neck in the 300 is the head. Gotta get it ported plus a port match to the manifolds. Probably best to do that when you get your new intake, carb, and header set up. I think an Edelbrock 500 would be a good match for that cam. Right now your power band is limited by the stock induction/exhaust and ignition system. Best wait on the DUI or dizzy recurve so it can be matched to the total build.

 

ok thanks i think i'll try to do the ds2 with the gm module. what are the specifics that i need to look for when i head to the salvage yard? will i have to change anything up on the wiring harness?
also how extreme of a port and polish job should be done to get what im after?

 

Dirt cheap Ignition Info on the HEI/DS2 set up. The 4-pin HEI module can probably be had new for $20 at a parts house. Since they get quite warm they should be installed on a heat sink. Same info here: http://www.gofastforless.com/ignition/tfi.htm

Fordsix Performance :: Log in The diagrams are for a SB6 but the principle is the same.

Fordsix Performance :: Log in

Info on porting and a 3 Angle Valve job at those two links.

http://www.google.com/search?q=Cylin...ient=firefox-a More info on porting there.

You want a port match (not gasket match) between the head and manifolds. Polish of the combustion chamber and exhaust side only. Leave intake side rough. Removal of casting flash, de-shrouding of intake valve, etc., is what is needed to improve flow characteristics. "Hogging" out or extreme material removal will usually make performance go backwards.

 

I don't know if I am tracking this question correctly or not. You mentioned a low power band in you're original post. I think that's the nature of the 300. Of course torque, hp can be improved, but won't they peak at about the same rpm? Torque about 2000, hp about 3000? Please correct me if I'm wrong (I'm stupid). I'd like to know.

 

BTW if you are going to have the head work with the valve job done it might be worth it to up-size to the 1.94/1.60 Chevy valves...not an uncommon modification.

 

He said a narrow power band...that cam has an advertised operating range of 1200-5200 rpm BUT, how well it operates within that range or even if the otherwise stock engine can see 5200 rpm is dependent on induction, exhaust, and ignition system to match. The stock head, intake, and exhaust is still the major bottleneck in these engines. When the numbers on my engine were run on Desktop Dyno the projected peak torque is at 3000 rpm and the HP at 4500 rpm. That is with an advertised 1000/5000 rpm cam.

 

ok so heres what i have so far:
edelbrock 500cfm 4 barrel with offy dp intake
long tube headers
port and polish exhaust and chev valves
ds2/hei ignition
any idea what i would expect for hp and tq when its all said and done?

 

Estimated projections can be made on a computer program called DeskTop Dyno. The only definitive way to come up with the numbers is on a dyno.

Look through this thread...quite a few combos run on DD with projected flywheel output: http://fordsix.com/forum/viewtopic.p...hlight=figures

 

Thanks for the numbers Harte3. I'm still learning about hopping up a 300 and you explained a lot. Good stuff.

 

The easiest and cheapest thing to do right now is the HEI module, and use EFI spark plugs gaped to 50 and you should notice an improvement in running as long as the wires, dizzy cap and rotor are good...basic tune up items.

 

i looked thru that link harte3 and i see alot about chev rockers. with my cam would they make any difference?

 

The Chevy rocker mod is usually a cheap and slightly effective upgrade on a stock cammed engine...not recommended on the bigger cams...they already have additional lift ground in. It has been done but there is increased and unnecessary pressure/wear on the valve train and clearance issues with the valve cover and little if anything to be gained.

http://fordsix.com/forum/ That site is THE information resource on modifying Ford I6's. Time well spent reading everything there.

 

ok i have a old 300 out of a '78 f100 that i have laying in the shed. will the head off of that engine match the head on my '86? i drive my truck alot so the quicker i can get the work done the better