I have a recently rebuilt 351m on my 79 f150. I am looking into performance upgrades and my search has lead me to Edelbrock. They make a 4bbl 600cfm carb with a performer intake that they match with a performance cam. They also reccomend new valve springs and timing set in order to guarantee a warranty. I am going to purchase a set of ceramic coated headers whether or not I do the intake upgrade. Does anyone have any experience with horse power gains on this upgrade? Let me know good or bad if you think it is something to do. I will do all the work myself so the parts will only cost me $800 after gaskets and bolts. Any opinions?

 

I have that exact set up in my 351M. Its no race motor, but it will pull my trailers like a champ. Ive had to tinker with that carb alot to get it right, though. Also, I had headers when I first built the motor. When they rotted off, I replaced with stock manifolds. NO DIFFERENCE IN PERFORMANCE!! Save your $ on the headers, or spend it on an MSD Ignition. Headers look cool, but are troublesome, and noisy. My .02

Nathan

 

nathan, I am not going to be hauling anything. It is my daily driver and I am of the philosophy: "Drive it like you stole it" Did your upgrades help you with hp off the line, or just torque?

 

Well slug, lets put it this way, it will smoke any stock 351M. If you are doing a rebuild, learn from one of my mistakes. Make it a 400 with 4" crank and 400 pistons. It wont cost any more, and is the BEST power upgrade for a 351M. I wish I had done it, but at the time I didnt know that that was all it took to get 400 ci. Oh well, next time (unless I put in a 460)

Nathan

 

Slug, i would also say learn from my mistake... but its too late, i did the same exact thing on my 79 with a 400. youre telling me the story of my life here =) i was power hungry and ignorantly thought that rebuilding the motor would really liven it up. wrong! i spent money on a complete rebuild kit consisting of stock replacement everything....if only i had known. it was a great learning experience and i had some fun, but it didnt really help. well after seeing close to no improvement at all on the tire squealing scale (hah) six months later i figured, oh, well ill turn it into a tire roasting beast by slapping on an edelbrock intake and a 600 cfm 4 barrel (lol) ...payed more money for a carb and intake and put it on there... (keep in mind the engine is still all stock minus some tiny cheap "bolt-ons" that made no noticeable differece either) well you guessed it, not the gains i was looking for, dont get me wrong it helped some...SOME, but it wasnt all that it was cracked up to be. although one thing i will say about it...while it didnt help off the line worth a squat, i could feel it open up when staying on it all the way to 4500 or so. it did widen up the power band a bit. if you dont mind the cash and labor, go with it, but if youre wallet is tight or you arent looking forward to a day of wrenching... its probably not worth it. now for what i wish i wouldve done: used flat top pistons for higher compression, a good dual pattern cam with decent lift in the 260-270ish duration range, and a quality "straight-up" timing set, rather than all the stock replacement stuff that came in the kit. i think with those mods it would really be pumping out right now, especially with the intake and carb. i really think that with the stock compression and cam, the effective modifications that can be done are very limited. but hey, you live and learn right? =) anyway, its all personal preference really do what you think would work best for you.

 

by the way, nathan...it sounds like you stand behind the msd stuff? ive been looking into performance ingition upgrades for both my 79 400 and now my 73 429 in an 83 250. do you have exerience with hi-perf. ignition systems? worth it/not worth it?

 

I havent used any MSD equipment, but have heard others say it is a good upgrade. I did put a Jacobs Pro Street ignition on my 95 460EFI. Threw my money away on that one! No improvements whatsoever, and it barely runs after I wash it. Now running on the stock EECIV ignition.

Still living and learning,
Nathan

 

Wow nathan, that really bites...i feel for ya on that one. do you suppose that maybe since the 95 is electronic everything and pretty technologically advanced as is, that that kind of upgrade would shine more on an older model? also...did the jacobs guys give you a quote on "benefits" for your specific application or did you use a universal kit? if they quoted you on hp and mpg gains and you saw nothing...it makes me wonder about the older stuff too...

 

The salesman said it would be more noticable on my 79 351M, but they advertise 15% gains in fuel economy and added HP and TQ. If anything, mileage went down, and any power increases (not noticable) probably came from opening up the plug gaps (gaps are still opened up with running the EECIV) I had even read a magazine article where they installed one one nearly the same truck as mine and they claimed to get better mileage, smoother idle, and "seat of the pants" power gains. I figured how could I go wrong! Oh well.

Nathan

 

KEEP YOUR STOCK IGNITION MAN. IF YOU AINT GONNA BE TURNING MORE THAN 6 GRAND MALLORY,MSD ACCEL ,NOTHING IS GONNA BE BETTER THAN STOCK.

 

I tend to agree now that I lhave had the aftermarket ignition experience.

Nathan