'75 351w in 91 GT

bergenn22

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Nov 30, 2009
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are their any complications with switching the 351 to efi??? what will i have to do for the ecu??? will 75 be a good yr for the 351??? i know everyone says 69-74 but i can get my hands on a 75 real cheap. do they have forged internals or am i going to have to buy a crank and rods?
 
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Depends what all your getting with the motor? If you use the stock cam you will need to repin the harness so the ECM fireing order matches the fireing order of the old cam.Or buy a new cam and have it ground to the new fireing order witch will match your ECM.As far as a good block or not? I beleive a 75 and up block will still hold like 6 or 700 horse?If your not gonna boost the crap out of it or spray the crap out of it i think a stock 75 block is good enough. Heres my link to my swap http://www.stangnet.com/mustang-forums/751223-my-351-build-pics.html peace






john:p
 
The newer 351s might have the same firing order, but the older 75's and maybe clear to 93 351's have a diffrent fireing order, but yes the older 351's have the same firing order as the OLDER 302's.And i beleive the 94 and up 351's have the same firing order as the 85 (or whatever year) the 302's went to a HO fireing order.All i know is my 74 351 IF USED with the stock 74 firing order cam would of required to either repin my 93 ECM harness or get a newer firing order cam.Depends how crazy you get?If you stick with 24# injectors you can "trick" the ECM with the proper calibrated MAF but this isnt suggested! I would get a chip burned for your stock ECM even if you use 24's or not!Or if you could get a 93 cobra ECM and run 24's cause the cobras came with 24's stock and the ECM is programed to them.Also i noticed in your 1st post if you go from a carbed 351 you will need a fuel pump block off plate and a EFI 351spacific dizzy.peace








john:p
 
did u ever get ur numbers to turn out any better??? my original intention was to put a full trick flow top end kit on my 302 and then twin turbo it next yr but the turbo kits are so dang expensive... i wanted to end up around 500-600 hp...
 
Not yet i havent.My problem is small cam and low compression.Once the funds are back i'm building my own turbo set up,and plan to convert to roller and get a custom grind cam.I figure doing and fabing everything myself will be a touch more them putting a big cam and high compression pistons in. peace








john:p
 
The newer 351s might have the same firing order, but the older 75's and maybe clear to 93 351's have a diffrent fireing order, but yes the older 351's have the same firing order as the OLDER 302's.And i beleive the 94 and up 351's have the same firing order as the 85 (or whatever year) the 302's went to a HO fireing order.

This is not true. All 351w's have the 1-3-7-2-6-5-4-8 firing order regardless of the year model. 302's before 85 and all non- H.O. 302's have the 1-5-4-2-6-3-7-8 firing order. 85 and up H.O.'s have the same firing order as all 351w's. Look this up, it is in many books and all over the internet.
 
i am pretty sure i am going to have to stroke it to get 500+ hp do you know how much? am i going to have to have it bored as well? what do u guys think about the tfs twisted wedge heads?
 
This is not true. All 351w's have the 1-3-7-2-6-5-4-8 firing order regardless of the year model. 302's before 85 and all non- H.O. 302's have the 1-5-4-2-6-3-7-8 firing order. 85 and up H.O.'s have the same firing order as all 351w's. Look this up, it is in many books and all over the internet.

Thanks for correcting me! I only said this cause when i was building mine this shop (obviously dont know what they are talking about) told me the fireing order was diffrent on my 74 351w then my 93's 302 fireing order. peace

john:p
 
i am pretty sure i am going to have to stroke it to get 500+ hp do you know how much? am i going to have to have it bored as well? what do u guys think about the tfs twisted wedge heads?

What kind of funds do you have to work with?If you stroke it i would go with a 427.I'm making just under 400 HP at the motor and close to 400 TQ at the motor,if i had more compression and a bigger cam or atleast a bigger cam i'd be well over 400/400 at the motor. Heads i think depends on preference.But i was told that AFR heads will pull top end over a set of identical trick flows,and trick flows will pull harder low end? So i have no clue?I have the AFR's and love them! But havent had any trick flows to compare them to. I do the the trick flow r intake tho.I could be wrong here but arent the twisted wedge heads valves bigger and just offset so you dont have to notch the pistons? peace














john:p
 
my ceiling at the moment is 5k and don't really want to go over that otherwise i can't do the complete build this yr... i just got laid off for the winter and don't go back to work till may
 
Sounds like you need to buy some books and do some reading. 500-600 NA on a 5K budget is some serious pipe dreams. Build a stock crank/rods Windsor and be happy with mid 400s at the flywheel, and that would be with a well-matched combo and properly tuned EFI setup without revving through the roof. A stroker like a 393 or a 408 could do it, but you'll be running through that 5K budget quick.
 
I agree with NikwoaC but an easy 400/400 is possible with $5000.Look at my build i posted.I'm close if not a touch over the 400/400 at the block with mine.BUT with a wiser choice of cam i would definitly be over the 400/400 at the block.Here is my list of parts from my build with prices,i think i mentioned what was used and new:

between friday and today the motor and trans is in! i need the swap headers (going tomorrow to get them) and new 4" rubber for the CAI.I said i would post prices of the stuff i have had to buy and what i used off the 302. well heres the list and some pics afterwards!
purchase of the 351w complete carb to pan $300
sold the old 302 $750
march under drive pullies off the 302 $ reused
reused stock fuel lines $0
reused stock valve covers $0
SCT chip bought used w/shipping $100
base tune burn on the chip $50 NOT A DYNO TUNE THO!
pig tail adapter for lightning maf to fox maf new $48.95 w/shipping
throttle body used 90mm in 75MM out accufab $150 w/shipping
fel pro headgaskets $83.12
this is all from summit so shipping is included and all this is new:
trick flow 351w EFI intake $663.95
AFR 185 58cc heads CNC $1411.95
trick flow push rod lenth checker $11.95
crane ultra gold rollor rocker $269.95
fel pro intake gasket set $20.95
crane hardened push rods $105.95
ARP intake bolt set $35.95
fel pro header gaskets $21.95
energy suspension poly motor and trans mounts $157.95
oil primer tool for 351 $12.95
summit alt bracket kit $69.95
FRPP billet steel flywheel $229.95
FRPP bolt and dowl kit for clutch $13.95
FRPP harmonic balancer 266.95
ARP cam bolt $2.95
ARP head studs $111.95
FRPP 9MM black wires $41.95
FRPP spark plug boot protecters $49.95
FRPP double roller adjustable timming chain set $62.95
luati cam and lifter set $221.65
MSD dizzy gear iron $13.30
MSD dizzy cap $19.30
MSD rotor button $4.70
FRPP for 351w swap oil pan conversion kit $135.88
FRPP 1 piece oil pan gasket $18.88
milodon water pump $96.95
used parts:
MSD efi billet dizzy w/10 hours run time $125 no shipping
90MM lightning maf and 42# FRPP injectors $280 w/shipping
all new hoses hose clamps 10quarts of oil 2galons of antifreeze 1mobil one oil filter 1 ford oil filter 8 spark plugs $165.00
2' of fuel line to connect fuel rails $18.00
new belt $12.99
misc bolts (about) $35.00
used 351w swap headers $150.00
new vacume line $2.00
breakin lube comp $10.00 to better see this list i beleive it's on page 6 of my build thread i posted a link to on here?peace












john:p
 
well i had the 5k limit on it if i was gonna get it done by spring but if that isn't realistic than i am going to have to make some changes... i found this sweet stroker build on trick flows site but i am sure that will put me way over my budget Strokers Wild: Part 2
 
Well unless your in a big hurry (like most of us and myself) i would build a stroker!AND if and when i do another motor it's gonna be a 427!I see it this way why do a 393 408 415 (or whatever it is) and not be happy with it BUT you did it cause of wanting it in a hurry or the funds?I feel (and i'm 100% guilty or this) build the biggest stroker that you can even if you have to wait!There really isnt much price diffence in a 408 393 or a 427 in the stroker kit it's self so why not just do the 427!If you do say a 408,well theres the cost for the kit and supporting mods heads,intake so forth.THEN you want to do a 427 well then your out the money for the 408 kit,heads,intake and whatever else wont go good with the 427,PLUS you will then need to rebuy alot or some of the stuff to have a nice 427 and you'll be out even more money!peace









john:p
 
Well unless your in a big hurry (like most of us and myself) i would build a stroker!AND if and when i do another motor it's gonna be a 427!I see it this way why do a 393 408 415 (or whatever it is) and not be happy with it BUT you did it cause of wanting it in a hurry or the funds?I feel (and i'm 100% guilty or this) build the biggest stroker that you can even if you have to wait!There really isnt much price diffence in a 408 393 or a 427 in the stroker kit it's self so why not just do the 427!If you do say a 408,well theres the cost for the kit and supporting mods heads,intake so forth.THEN you want to do a 427 well then your out the money for the 408 kit,heads,intake and whatever else wont go good with the 427,PLUS you will then need to rebuy alot or some of the stuff to have a nice 427 and you'll be out even more money!peace









john:p

When you start to go bigger than standard-bore 408, you start to get into extreme rod angularity and short compression height pistons, which is the reason most people don't go higher than 408.
 
When you start to go bigger than standard-bore 408, you start to get into extreme rod angularity and short compression height pistons, which is the reason most people don't go higher than 408.

This is good to know! I surely didnt! So maybe i'll stop at a 408 or a 418 when i do my next motor.So by what you described about the 427 is that the same thing you run into when going to a 347 out of a 302? peace




john:p