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69 Mustang- 302,351w, roller block,efi?

2K views 15 replies 8 participants last post by  ScoTFrenzel 
#1 ·
So here's my current situation. This is my first project. I just bought a 1969 mustang coupe body. It's a straight body and it has just been repainted. I shouldn't have to do any body work to it. It has a mild suspension, and drum brakes but not much else.
So now, i plan on building up a motor, the problem is, there are just too many options and i don't know where to start. This is my first engine rebuild and i'm just getting into the hobby so i haven't built up much of an opinion yet; i'm clay waiting to be molded.


So now, i'm going to ramble a little bit to give some idea of where i'm at, maybe you guys can pick something out of what i say and give me any advice you have.

I want a motor set on power and torque. I realize gas mileage is gonna be awful either way so i'm not going to worry about that. So the other factor is price right? Well, i don't want to spend an absurd amount, but i want to get a good motor that will bring good resale value to my car.
I read a lot of articles on the 5.0L 302 from newer mustangs, and that seemed like a good option, maybe get 400 hp. But then the 351w came into the picture. A stronger block, more torque, more potential?

So, i would like to make 450 hp +- 20 hp.

My options for blocks/engines are pretty endless. There are all kinds of 302 roller blocks available in my area, and i also found a 351w roller block for $400. For 400-450 hp, do i need/want a roller block?

---So lets say i get 351w. If i get a shortblock somewhere, should i be concerned with what it came out of, or just whether or not it's a roller block? How much of a difference is there?

Originally i thought i would be able to put some twisted wedge heads, an RPM performer intake, and a 650 carb and get some good performance. Then maybe step it up to 400 hp with cam. Is that likely?


I'll stop rambling now, hopefully that's enough information to get started. I'm sorry it's so jargled, that's just where i'm at right now, my mind isn't working too well, i've just picked all of this up in the last 2 weeks.

Thanks
Travis
 

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#2 ·
First, I'd dump the drum brakes. Beyond that either engine will be a drop in. I think you would be better off with a roller block, but that's not a requirement. You will need to change pistons if you want twisted wedge heads...that's just part of their design and flow. If you want the amount of HP you state, the bigger engine will give more cushion as far as reliabilty/driveability. An EFI off a donor car will be easy to adapt. By the way, did I mention..get rid of the drum brakes. I repeat that because too many times the engine is all that's focused on and if you want an enjoyable,safe ride the whole car needs to be addressed. 400HP in an early Mustang with no suspension/brake upgrades, will get old quick.
 
#4 ·
Personally, I'd go with a late model EFI setup including the overdrive transmission. But if you want to get 400 HP, are you ready to tackle upgrading an EFI system? It's going to require a larger fuel pump, injectors, fuel rail, injectors, fuel lines, etc. not to mention an aftermaket computer or an add on hacker module.

I just finished a 70 coupe and regret not going with EFI and overdrive, but that's just me.

http://www.hotrodders.com/forum/journal.php?action=view&journalid=20616&page=11&perpage=5&reverse=1
 
#6 ·
As mentioned,put some thought towards an OD tranny.Proper gearing selection will make a huge difference and will help with gas mileage.Most AOD's today use a low 1st gear,so you can use a mid range rear end gear,3.3-3.9:1,for example,and have lots of bottom end,but reduced RPM's on the highway.
Guy
 
#7 ·
start over and re-think what do you actually want to do with the car when done???

if this car will be 90% strip/10% street then do key in on a HP goal to hit a ET/MPH versus car weight goal...

if it's a cruiser key in on MAX possible low rpms TQ which is the acceleration force you feel pushing you back in the seat and makes a really fun to drive on the streets car....

HP=torque measured over "distance" and "time", aka a drag strip
TQ=brute force! multiplied by the gears twisting the hides!!!...

ex: 69' 428 cube "Super Cobra Jet" was only 335HP....but made about 500ft-lbs of TQ WOT at only 2k rpms and came stock with 3.89(?) gears....a absolute beast on the street!!!
 
#8 ·
It's definitely 90% street and 10% strip, so i want to go with low end torque.
I want a manual transmission, and i really don't think i want to do EFI. Like Arrowhead said, i don't think i'm up to installing new fuel rails, injectors and a different computer module.

I'm thinking now, that i want a 351w roller block with a 5 spd from a 5.0 mustang. If I want low end torque what are your suggestions for going carbureted?
650CFM carb? Performer, or Performer RPM setup? I think i want twisted wedge heads and an edelbrock intake. I read that the edelbrock power package with roller cam puts out 480 hp for the 351w. If i put on twisted wedge heads, i could expect more than that right?

My other question is, how bad of an idea is it to take an older block and convert it to a roller block?
 
#9 ·
If it was me,I would use a good dual plane intake,Weiand Stealth or Edelbrock RPM Performer and a double pumper mechanical secondary 750 Mighty Demon carb.As for useing a roller block or converting,if you are going with aftermarket parts it wont make much difference.If you use a performance cam in a roller block,I would replace the stock roller lifters.
Guy
 
#10 ·
351-flat top hyper pistons,reworked rods with arp bolts,fms 303 cam, rpm intake ,600 carb with any set of heads other than tw. more options down the road. small carb for the seat of the pants feel, better port velocity.shoot for 9.5 compression. most any ign will work well.
 
#11 ·
If you are thinking 450 hp and 450 torque from a 351 W,
then any T-5 transmission from a Mustang GT is out of the question.
It won't be very long that ANY T-5 will blow apart.
Tremec 3550 will be a minimum. A Pro 5.0 or Steeda shifter is a minimum on either transmission.

More moderate power (350) and street tires, a heavy duty T-5 will live.

Roller cams will eliminate any concern over bad lobes on flat tappet cams..
 
#12 ·
ScoTFrenzel said:
If you are thinking 450 hp and 450 torque from a 351 W,
then any T-5 transmission from a Mustang GT is out of the question.
It won't be very long that ANY T-5 will blow apart.
Tremec 3550 will be a minimum. A Pro 5.0 or Steeda shifter is a minimum on either transmission.

More moderate power (350) and street tires, a heavy duty T-5 will live.

Roller cams will eliminate any concern over bad lobes on flat tappet cams..
Anything can break at anytime. My good friend has a 85 mercury capri, with a fuel injected 351 with rpm heads and 351 ho flat tappet cam. It runs mid to low 12's on slicks through a t5-z. Nothing has broke yet and this car doesn't get driven nicely.
 
#13 ·
RippinRon said:
Anything can break at anytime. My good friend has a 85 mercury capri, with a fuel injected 351 with rpm heads and 351 ho flat tappet cam. It runs mid to low 12's on slicks through a t5-z. Nothing has broke yet and this car doesn't get driven nicely.
A "Z" never came in any Mustang GT, and it is 10% stronger than any World Class HD rated T-5. Still borderline for a W, IMO.
 
#15 ·
pyro,
don't be misled by 6,000rpms mega HP numbers....
(you don't drive a car at WOT 6,000rpms on the street!!!)
you want your parts combo to make best/most/max power in the rpms range you do "actually use" and make the best power possible at part throttle!

what you do want to study is dyno results for parts combo's that do show the whole rpm's range
(from idle on up is best)

to illustrate just the rudimentary basic principles, click on each cam chart on this comp cam's dyno results link to study the actual TQ and HP power chart results at the same rpms (like 2500) versus the $$$$ parts needed/dictated by that cam profile at the same cubes and CR....

http://www.compcams.com/Technical/DynoSheets/

you can also compare roller (lower charts) versus flat tappet results with the same parts at the same CR on that link

two favorite, ever so true Max Keith (a member) sayings:

"ALOT more gooder isn't necessarily more gooder" (in the real world) and "motor HP increase = $$$$ spent x cubed" (on the whole car for tranny/suspension/etc).....

just as important for building a really WOW neck snapping street combo is the gears selection...(tranny and rear gears)....
it's simple math:
flywheel TQ x tranny ratio x rear gears = total force twisting the hides!!!
vehicle weight/total force = motor wind up rate

a bone stock 250HP 2V 351W crate motor with (ridiculous for the street) 5.11 circle track rear gears will truly snap your neck off....
350ft-lbs x 2.46 first gear x 5.11 rear gears =4399 ft-lbs of force on the tires patch!!!!
3400lbs car weight/4399=.77lbs of weight per 1 ft-lb of force
(LOL, correction, with those gears there is no force on your neck, it would just sit there and burn the hides down to the cords with that much force!)
450HP/420ft-lbs(?) 351W x 2.46 first gear x street friendly typical 3.55 gears= 3667 ft-lbs on the tires...700 less ft-lbs with 200HP more

because there are so darn many very good, very general motor choices and drive train possibilities, it is darn hard to offer even general suggestions for your particular car....
 
#16 · (Edited)
pyr0
I guess my point is to not spend money on a trans that might go boom. Spending more money one time is a lot more efficient than having to throw away a blow up and start over from scratch.

There are quite a few 351W cars with T-5 trans out there, but an old used trans with 75,000 hard shifted miles on it is NOT the place to start your project. Even a trans HD rebuild costs upwards of a thousand.
Consider that Pro5.0 or Steeda shifters mandatory for any T-5, or it will frag.

Also the Ford factory type fuel injection intake manifold is a horrible design for airflow, a massive compromise for low speed efficiency and smog control. A study in 5.0 Mustang hop ups will prove that to you. In almost any case installation of a 4 bbl increases upper rpm hp significantly.... like 35-75+ depending on what the engine is.
Remember all those fancy aftermarket fuelie manifolds exist because they had to maintain smog compliance, not because they made more power than carbed intakes.

and ya, one of my personal cruiser rods is a 5.0 HO fuelie T-5 and I love it. It is wonderful to drive, gets 25+ mpg with the ac on, and runs 9.2 in the eighth, stock engine. 50 times I have considered dropping on a carb and instantly picking up 50 hp and losing 5 mpg.
 
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