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Discussion Starter #1
Ok, picked up a 5.0 EFI engine for $75...it's greasy but it's clean inside. Due to my circle track racing i have a sponsor who will do all my machine work for free so machine work isn't an issue (to a certain extent, i can't ask too much of him.)

Heres my plan:
Swap the EFI for carb.
.040 bored out
shaved heads (only shaving as much as i can without swapping lifters)
Shaved crank? (can it handle the power)

ok, so heres my questions,
  • COULD i hypothetically speaking, bore it out .040 without any modifications to the crank or heads?
  • How much could i shave off the heads using all stock internals on the head?
  • I've heard the 5.0 cranks have bad reps on strength, so could i shave the stock crank and still have it be able to hold up to whats being thrown at it?
It's not a crazy build...just a little bit right now to at least get some power and get the engine in the car...later there will be more work done on the heads and cams, but as it sits that's my plan. Please help me with these questions and give me some feedback and tips on what you think.
 

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well in my opinion you dont need to shave the crank and as far as stock ones not holdin i beg to differ my buddie has a 93 fox with stock rotating assembly with 150 shot of nos and has been running it for 3 years now all u need is some good heads if your goin carbed go with 289 hi po cast iron heads (closed chambered) if u can find them or go with 351w heads the bigger the valves the better the hp and responce you will be looking for in my 91 fox i have 289 hi-po heads with 2.02 intake and 165 exhaust valves its a beast with 11.1 compresion on 89 octane, and get u a e303 cam or fireball crane cam if you would like somthing a little better than a rv cam. but if anyone else has a suggestion let us know.:bigthumbsup
 

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let the machine shop tell you what bore you need, 40 over is the limit of a 302, if the walls and crank are in good shape a standard 10 over may get it back to spec on bore and crank turn.
 

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The stock crank is strong enough to split the block so don't worry. Let the machine shop check the block out and see what it needs maybe just a hone job cause you never know.

As far as heads well if you are playing the budget card then a set of GT40's will be your best best as you can find them relatively cheap. If not start searching for some used aluminum heads.
 

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Discussion Starter #8
Thanks for the info guys,
I've heard 40 is not always bad, but i do take into consideration it should be checked out. So maybe to play it safe let's say i go with .030 over.

Is it even worth it to shave the heads? even a little? it's probably going to be temporary for a few months until i can get new heads but i figure i got the heads, the machinist willing to do it, might as well?

thansk for the info guys, hopefully have some work getting started soon
 

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It is not worth dumping money into stock heads. If you look around you can find GT40 heads for the money that you will be putting into the stock heads. Mind you that the GT40 heads will need at least to be checked out and have the springs swapped out for something a little stiffer.
 

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Discussion Starter #10
But if the machining is free? i could shave a bit, use em while i get a new set of heads and build those ones up off the car and then swap em out at a later time. Or would i HAVE to put $$$ into the stock heads if i shaved em?
 

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let the machine shop measure and let them handle their business. Its what they do best.

i may also add that the word "shaved" somehow doesnt sit well with me. Can we just say flycut or mill..grind..anything but shave?..idk my petpeeve :kooky:
 

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Yeah you will increase compression but it will also mess with valvetrain geometry, quench area, intake fitment and a whole bunch of things if done incorrectly.

Stock heads do not flow well at all and that is where the problem lies. If you think that you can get an extra point of compression from milling the heads well you might just pick up 5 hp then.
 

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Discussion Starter #15
So maybe a port and polish would be a better option for the stock heads while i await some better ones...would that be a better option?

Thanks for clearing that up about shaving the heads, i didn't take into account all the problems it would cause, my racecar is 2.3L so you don't have to worry as much about the intake fitment and stuff when shaving the heads.:winks
 

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switching to carb? well to each his own, and just to put my 02 in about the stock crank, iv run a 100 shot in my stang for a year with no problems. iv meet others on other fourms that have sprayed up to a 150 shot with never even opening up their valve covers. shaving them would bump up your compresion a tad but i would def run into problems later if u decided to upgrade to a bigger cam:bigthumbsup
 

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a guy i use to work with ran a coupe car that was all stock...all he done to the car was zero the block...shaved or milled the heads like .010 or 0.150 (dont exactly remember, but it wasnt enough to mess with geometry) and shaved the intake to match...and it was pretty quick....he dropped an automatic and put 4.10 gears in it and it was a mean red light warrior...he just did that so he could get the satisfaction from when people asked him "man what all have you done to that car?" of popping the hood and having a stock motor in it...if you plan on leaving all the smog on...id leave it EFI...mine runs pretty good with all the smog stuff off and not hooked up...but I just like getting in it during the winter and not worryin about the thing giving me trouble starting
 

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Discussion Starter #18
Yeah, but if i were to bore it out, shave the crank, then go to put the EFI on would i have to do much tuning to get it to run right? With the EFI i'd have to get it tuned and i figure at ;east carbbed i can do it all relatively easy without messing with the computer. I guess i don't know enough abou the EFI setup to feel comfortable with it
 

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Yeah, but if i were to bore it out, shave the crank, then go to put the EFI on would i have to do much tuning to get it to run right? With the EFI i'd have to get it tuned and i figure at ;east carbbed i can do it all relatively easy without messing with the computer. I guess i don't know enough abou the EFI setup to feel comfortable with it
unless you know alot about carbs, really efi is easier to tune and safer. make sure your maf matches your fuel injector size, check your timing and sparkplugs, if it runs like ****, then take it to the dyno and pay like a hundred bucks for them to check it out and burn you a chip, i dont despise carbs, they are great on 500hp cars, but you never seen carbed cars back in the 70s era that got 200k on a motor,
 

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i love carbs. i just converted mine. but to set the record straight, rebuilding the engine with boring the cylinders and turning the crank will not effect the EFI!
 
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