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Discussion Starter · #1 ·
Does anyone have any links on extensive right-up on "The ultimate naturally aspirated 347"?

After speaking to some local racers and people in different message boards, I finally made up my mind to go all out and build a strong (pump gas) motor.

I need to know your opinion on THE BEST!
One note that I want to make is not to get too crazy. I have no intension on purchasing sodium filled or titanium valves. I also want to be able to idle at a light where I'm not jumping right into 4000 rpm from a dead stop.

I already have the crank and rods that are supposed to be rated to 600+HP. I would also like to eventually spray it with a 400HP kit.

As for heads, is bigger always better in my case?

This motor is going into a 68 Fairlane: 3250lbs/C4/9"-4:11
 

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Figure atleast 2000 for a block right off the bat. There is no ultimate per se'. Far too many variables here.
 

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From what I understand, stock 302 or 5.0 blocks have a tendency to split down the lifter valley as you approach high HP levels (+400RWHP). So as the previous poster suggested, you'll need the stronger block for your foundation. Ex Dart - $2200.
 

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Start out with a tall deck wide/big bore block. These can be found at a wrecking yard and are good for 700+ HP.

Grab a stroker kit with a super long stroke, say 4.5".

Get a set of heads, about 2,000 bucks will get you out of the box heads that will support over 700 HP.

Oh yeah, this will turn your engine into a 545/557 if I forgot to mention it!

Greg
 

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Sell the stuff you have and build a 427+ windsor or better yet "the Big Block Solution"............what Gregp said !!

_________________
1991 LX Mustang 347 C4 combo 11's with the AC on.
1984 Mustang GT 460, Powerglide "Its alive !!!" Mid 10's out of the box, high 9's on the way !!
1929 T-Altered "In the works" 8's are on the horizon

<font size=-1>[ This Message was edited by: dfree383 on 8/31/06 10:59pm ]</font>
 

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Ultimate for what? Street? Strip? Brackets?

I get concerned when I hear that you don't want to pop for the valves and other HD stuff, but you have a 600 hp recip assembly and 410s.

Guys do take production blocks and stroke them but you really need a good sonic report before you get too crazy with a 400 hp shot (!) and gears, which mean it will be winding high a lot of the time.

Ford would have done it themselves and skipped the 351W tall deck bloc if they thought a stroker crank would not pound hell out of the thrust side and egg shape the bore.

The best bet is to get a quality HD block -- the Ford equivalent of the Chevy "Bowtie" and build from there. It will last a lot longer, seal better and make more power.

Most important thing of all is to do it as a complete package -- match headers to intake to carb to cam to compression to recip to trans, axle and convertor.

My experience has been to go less expensive and less radical with the engine and spend the money on the chassis, trans, convertor, gears, etc and make the thing hook. With a good foundation engine, you can amp up the cam, carb and intake without a lot of trouble as you sort out the rest of the car.

There are a lot of guys here who have built 347's so they can give you all the part numbers, LSA's, compression ratios, carbs, gears, yadda yadda. They've lived them and troubleshot them for years.

IMHO, though, a 347 is a little small for a Torino/Fairlane. If I was building another '66-69 Fairlane/Cyclone/Comet/Falcon, I would do a 406" stroker in a minute over a 347. Cost would be about the same and the torque would be substantially more, weight penalty would be only 50-60lb, if that. Wouldn't need as much cam to make the same power, street manners would be better. Probably ET pretty well if it would hook, too.

Good luck!
 

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Discussion Starter · #8 ·
WOW! This response is great. Thanks for the feedback that I’ve received so far.
Here are a little more details of this project:
I plan to retro this car and go through the suspension around tax time. I met one of the custom painters from “Overhauln” and he plans to help me out with a tricked out paint job, a 4-link suspension, and some type of reinforced roll bar so I can be legal on the strip since it’s a convertible.
As for going with the bigger cubic inch, I’ve always been partial to the smaller mouse motors. I find it more challenging and some what funny when I sit next to a 454 rat motor and actually stand a chance. When people ask for the size, it’s funny to see their expression.

I have already massaged the block. Cylinders bored .030 with a torque plate, the mains line bored and the block is studded.

This car is going to be used for shows and once in a while, taken to the strip or pounced on at the light. It may see 3000 miles/ year when it’s done. Actually, in the past 5 years, it may have collectively seen 4500 miles with the 302ci.

As for my finances, I plan to spend what ever it takes to get the high HP in the heads, intake, carb, and exhaust. I actually just purchased a 750cfm DP.
As for the Nitrous, I actually typed (400) what I was thinking and not what I would probably actually use. Realistically, I would probably use a 250HP shot. I currently have a sniper that will hit 125HP. When I get this new motor together, I plan to start small (around 75), and work my way up after the motor has been properly broken in.
One experiment I really want to do is build this motor with a solid mechanical cam and then next year, upgrade to a roller. I’ve never ventured into these cams and would like to see what HP I could squeeze out.
I may go with a better block next year but I want to see what I can do with this one.

My goal would be to at least see 550HP at the wheels and land in the 1/4mi in mid to low 11’s. I’ve mentioned this before in another post but this is my main drive.
My very good friend that used to own this car has a 2003 Vette. We have been talking for the past year about racing. Since we were in High school (in the 80’s), we’ve always been VERY competitive. As of last weekend, I discovered that he just went out and installed a small Paxton blower, new exhaust system, reprogrammed computer, and he is thinking of replacing his gearing. He told me last week: “I don’t care what you do, you don’t stand a chance, I’ll even give you 5 car lengths”. I told him we’re going to be fair about it and do it straight up.
All he knows is that I’m rebuilding his old 302 and that I’m putting a cam in it.
Now my buddy has very little experience in drag racing. In fact, when he first took his vette to the track, his fastest time was 14.05. Although, he has returned to the track at least 5 times. As for myself, I’ve been drag racing for many years on bike and car. I also poses the mechanical experience where he goes out and tells people to “bolt this on”.

“Now you know, the rest of the story”
 

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Forget the stock block......go Dart.

Custom solid roller cam, AFR 205/225 heads, Pro Systems Carb.

That's what my direction would be for the application & goals you've outlined.

Others may differ though.
 

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Oh.....and since I would be getting an aftermarket block, I'd also go with the bigger cubes. That means a 351W stroker in the 427 cid neighborhood.
 

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with your plans all your gonna do is trash the rotating assembly when the block splits down the lifter valley, thats a guarantee. The only time you build a smaller motor is when you want less power, less torque, cant fit a big block or run a class that has cubic inch rules. Your setting yourself up for disaster, I wish you luck
 

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first...get your goals clear.

You started off asking for 347 info. There are several articles in the Tech Dept covering building 331 - 347 stroker motors, matter of fact, there is a forum on-site that covers stroker motors and another that covers Dyno results.

A little "lite" reading goes a long way in helping you make some realistic decisions about what direction you need to take.

The best reason to build a stroker motor, especially a 302 based engine is either the "stealth factor", class restrictions or packaging (meaning the size of engine bay is too limited to accept a larger block - 351 or BBF), other wise, its money in the bank to go for more cubic inches or stronger foundation at the start, rather than go into the project knowing that your first job is to spend money to "catch-up" to the size of bigger motor - before you even start the hot rodding performance upgrades.

The biggest mistake most guys make when going for big power at the lowest cost, is to close their eyes to obvious alternatives and common sense. Believe the old wisdom...there is no substitute for cubic inches - except, maybe Cubic Money!
 

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Discussion Starter · #16 ·
The "Stealth Look" is defiantly an avenue that I'm heading down.
As for the belief of more cubes, I fully agree with the old sayings.
Although, I’ve seen a lot of small motors put a big block to shame. I had a good friend that built his 55 chevy with a 331ci that did mid 9’s and the car was steetable. I know he invested around $10k into the motor but the point is, that you can make a small motor very powerful. Don’t take this last statement wrong. I know from basic physics that you simply go with more ci if you want more HP.
I'm not out to build a drag car. The car is mostly a show car that simply goes fast and has an incentive to beat a vette.
It was stated to get my goals straight, they are straight. I want to continue building what I currently have. I'm not changing what I've invested in.

As for spending time searching the web and reading other articles, I’ve spent many many days reading forums, posts, “official documentation”…
I opened this post asking for the location of any documentation. I’m a new subscriber to fordmuscle.com and haven’t actually learned my way around yet.

It's been a suggestion to replace my block. Well, I might but not now. If there's a limitation then please tell me what that limitation is.
I came to the readers to help me out. I like to hear the details and stories of what everyone has done and hopefully hear from some professionals with experience that I could learn from.

How far can I push what I’ve already invested in?
 

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Where do you plan to get the crank and rods from? If you want to make 550rwhp with 347 cubes, it's gonna take some RPM to do it... and with the long stroke the 347 already has, you're going to need a very strong crank, rods and pistions. 550rwhp means at least 675fwhp, which is putting you right at 2hp per cubic inch... which is not unheard of naturally aspirated, but takes a lot of RPM to get there (plan on peak power at 7000-7500rpm). Also since it sounds like you're using a stock block, I'd look into doing 4-bolt mains. I don't know if people do this on 302 blocks or if that's a bad idea, but at least get a beefy main girdle to help the bottom end out, and the best bolts (ARP) you can buy throughout. You also might want to o-ring the deck and heads if you're going to really spray the N2O at the 250+hp level, as that will be pushing you well over 800 crank HP (given the 550rwhp you states was all motor), and that's a LOT of cylinder pressure.

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'85 Ranger, 350hp 289, T5, [email protected] (1.96 60') on street tires



<font size=-1>[ This Message was edited by: Motorhead on 9/1/06 4:12am ]</font>
 

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The STOCK BLOCK is going to SPLIT like firewood. 4 bolt mains only weaken the weakest area of the blocks, the main webbing. All a girdle does is hold the block together when it splits. Your dreaming about running a 400 shot. All your gonna do with a stock block at your desired HP levels is cry when its all junk. The only chance you have is to use a HI-PO 289 or Mexican 302 block. The stock blocks break at all different hp levels, sometimes, 350 at the tire, sometimes 400 at the tire. There is one guarantee, it will split right down the lifter valley. You need a block, period.
 

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Discussion Starter · #19 ·
So Woody, you're saying that you wouldn't recommend going over 400whp with my setup?
By the way, I corrected myself in the N2O. I was writting what I was wishing to push, not actually what I'd like to spray.
From your recommendation, I should probably stay with the 150HP sniper system that I have and not upgrade until I replace the block, correct?
 

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Discussion Starter · #20 ·
To answer Motorhead,
I already have a Scat crank and Eagle rods.

Woody,
If I'm only going to spray with 150HP tops, and keep my HP below 400HP at the wheels (which is very weak) I should be good with hyper pistons, correct?
Man, if this is true, this really sucks!!! This would really blow my idea of having that motor.
Maybe I should just give up on this incredible HP idea and focus on that next year. I could use that as my winter project. All in all, I want to get this on the street before the season is over. Stick with everything that I currently have, add a good set of aluminum heads, a custom ground cam, a good exhaust and have fun with that.
 
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