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Old 07-02-2008, 12:09 PM   #1 (permalink)
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351W built for max torque @ low RPM

I remember seeing an article somewhere about tricks for using longer con rods& shorter pistons or something that generates more TQ.

Anyone ever heard of this?

Also I remember seeing a book at Borders about Mustang 5.0 dyno pulls that mentioned a home made intake manifold where they lengthened the intake runners to increase TQ.

I seem to remember they made the runners 11 inches longer and it added 40 ft lbs below 3500 R's & subtracted 40 HP at 6000.

Since the efi 5.0 from a 90 Stang, thats in my Bronco hardly ever sees more than 3500, the extra 40 ft lbs would be handy.
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Old 07-02-2008, 12:27 PM   #2 (permalink)
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should have put a 400 in that 78 then over the weezer.
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Old 07-02-2008, 06:53 PM   #3 (permalink)
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Wait, so are you wanting to build a 351w for max low end torque (as the title states), or are you trying to get more torque out of a 5.0 (good luck, lol).

Either way, here's my take.

What you are referring to with the longer rods (assuming you are still talking about the 351w), is known as a 351 long rod. It uses a 6.125" rod with the stock 3.5" stroke and a ~1.6 compression height piston to achieve a better rod ratio. This provides more dwell at the top of the stroke which, in theory, will make more power. In reality the amount of torque gained is minuscule, I think its about 2%. Don't waste your money.

So, if you want brute low end torque windsor, ditch the 5.0 altogether and go straight for a 351w. If you can afford it stroke it out to 393, 408, or even 427. If you can't afford to go that big you can still get decent numbers on a stock 351" motor.

I'm running a mildly built 351w in my '79 and it provides amazing low end torque, and roughly 300hp/400lb-ft. Here's what I'm running:

-D4AE-DA block, .060" over
-stock crank and rods
-9.25:1 CR speedpro hypereutectic pistons
-All ARP fasteners
-E7TE heads, ported, polished, bowl blended
-Crane roller rockers
-Comp extreme 4x4 cam, 206/214 duration @ .050, .477/.493 lift
-Edelbrock performer intake
-Shorty headers, HEI, Q-jet

Excellent torque curve for wheeling:


I haven't messed with any EFI 5.8L's yet, but for brute low end torque the stock intake setup doesn't look too bad. I think edelbrock also makes one that especially geared towards more low end, with quite long runners. Installing a spacer between the upper and lower intake is another option.

What ever you do don't let anyone talk you into a 347 stroker. They are the biggest waste of engine building money I can think of. Just go straight for a 351w.
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Old 07-03-2008, 05:57 AM   #4 (permalink)
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Do a search for "393 stroker" or "408 stroker".

If your crank needs turning, you can buy a new 3.85" crank for just a few dollars more, then throw some 302 pistons into your 351 block, use your stock rods and presto: 393 stroker. It's what I'm building for my EB.
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Old 07-03-2008, 05:45 PM   #5 (permalink)
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I just dropped a built 351w to a 408 into my early bronco havent driven it much yet but just up the road to the exhaust shop and the torque is somewhat retarded. I would highly recommend it with stock heads and high compression a mild cam, roller tip rockers and such i have an estimated 350-450 hp and 450+ ft/lbs. it hauls ass to be honest. the cheap route that i have heard of is taking a ford 400 crank putting it into a 351w with stock 351w rods and then 302 pistons gives you a makeshift stroker kit and higher compression, I dont know the exact specs and i havent seen it done but it would be worth looking into.
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Old 07-03-2008, 06:42 PM   #6 (permalink)
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Originally Posted by 4xBronco View Post
I just dropped a built 351w to a 408 into my early bronco havent driven it much yet but just up the road to the exhaust shop and the torque is somewhat retarded. I would highly recommend it with stock heads and high compression a mild cam, roller tip rockers and such i have an estimated 350-450 hp and 450+ ft/lbs. it hauls ass to be honest. the cheap route that i have heard of is taking a ford 400 crank putting it into a 351w with stock 351w rods and then 302 pistons gives you a makeshift stroker kit and higher compression, I dont know the exact specs and i havent seen it done but it would be worth looking into.
I'm going off my memory here, but the 'cheap' stroker kit you speak of is done by running a 400M crank, Chrysler 360 rods, although I don't recall which pistons are used.

You have to turn the end of the crank down so the timing set sits flush, and turn the rod journals down to 2.124" to fit the Chrysler rods. When you do this you can also offset grind it by as much as .125" which with a .060 overbore nets 427cu. in. You can offset grind it less, and get less displacement and compression.
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Old 07-03-2008, 07:51 PM   #7 (permalink)
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im sure there is many rotating assembly combinations that can be used for multiple specs but i am almost positive a 400m crank with stock rods and 302 pistons can be used. As for the modification to the crank you mentioned i would not be surprised as no customizing goes smoothly but like i said i have heard of this never experienced or known anyone that has tried it. Personally i would not consider these "budget" builds as the cost of having it properly built is fairly decent now days.
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Old 07-05-2008, 06:43 PM   #8 (permalink)
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I'm going off my memory here, but the 'cheap' stroker kit you speak of is done by running a 400M crank, Chrysler 360 rods, although I don't recall which pistons are used.

You have to turn the end of the crank down so the timing set sits flush, and turn the rod journals down to 2.124" to fit the Chrysler rods. When you do this you can also offset grind it by as much as .125" which with a .060 overbore nets 427cu. in. You can offset grind it less, and get less displacement and compression.
Cheaper yet would be an Eagle crank, stock rods, and 302 pistons. I build my 393W on a pretty tight budget. Spent $1k and had to buy a new intake and distributor. I wouldn't hesitate to build another similar for another project.
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Old 07-05-2008, 08:10 PM   #9 (permalink)
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I'm going off my memory here, but the 'cheap' stroker kit you speak of is done by running a 400M crank, Chrysler 360 rods, although I don't recall which pistons are used.

You have to turn the end of the crank down so the timing set sits flush, and turn the rod journals down to 2.124" to fit the Chrysler rods. When you do this you can also offset grind it by as much as .125" which with a .060 overbore nets 427cu. in. You can offset grind it less, and get less displacement and compression.
I think I remember that write up in one of the car mags and IIRC, they used SBC pistons(?) Also, I think they had to add weight (mallory metal....they called it) to the journals to get it to balance right. After all the extra machining to make it work, you'd probably be better off just buying the stroker crank. Scat made them and Summit also sold them.......they were cast, by the way and reasonably priced. However I built the 351W for my EB for next to nothing. Car Craft did a series of articles called "Junkyard Wars" and I used it as a "somewhat" blueprint for mine ...I paid $350 for a motor, trans (C6) and t/c, sold the the trans and t/c for $300 and freshened up the lower end and topped it off with some '68 small chamber 302 heads that I had some light port work done to and '69 351W sized valves installed, an Edelbrock performer intake and carb (gotta get rid of that thing) and it runs real strong and is so much torquier (sp?) than the 302 I used to have! --------Hans
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Old 07-05-2008, 08:48 PM   #10 (permalink)
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Cheaper yet would be an Eagle crank, stock rods, and 302 pistons. I build my 393W on a pretty tight budget. Spent $1k and had to buy a new intake and distributor. I wouldn't hesitate to build another similar for another project.
I never said it was going to be cheap, just quoting the other guys description. Basically what I described was the way it was done before the multitude of companies became interested in the windsors and began making stroker cranks, rotating assemblies, etc. The only way it would still be cheap nowadays would be if you had in-house machining abilities. However, with as much a 427" kit cost I best going the old-school route may not be that expensive in comparison. For 393" buying a cast 3.85" crank is definitely the cheapest way to go.
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Old 07-06-2008, 09:18 PM   #11 (permalink)
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My origional post was confusing.

Ive had a 351W in an EB before, was a stock 351 2 bbl from a Econoline van.
Loads of torque.

I dont know why anyone would bother with stroking a 302, when a 351 bolts right in.

Currently have a 90 efi 5.0, but its got a burnt valve.
t-case needs rebuilt, back axle needs rebuilt.

Basically a drivetrain transplant.
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74Bronco EFI 5spd
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Old 07-07-2008, 10:34 AM   #12 (permalink)
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The 351w long rod motor you were probably looking at is the one were they used modified 400m rods, theyre 6.580" long, and then a stock 351w crank. I have an old car craft article were they ran this setup, and supposedly were able to run 11:1 compression ratio on 87 octane fuel.

SpeedoMotive sells a kit if you really are interested.
http://www.speedomotive.com/ps-105-1...roker-kit.aspx

If i could find my magazine id try to get some more facts from it.
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Old 12-28-2008, 10:42 AM   #13 (permalink)
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The 351w long rod motor you were probably looking at is the one were they used modified 400m rods, theyre 6.580" long, and then a stock 351w crank. I have an old car craft article were they ran this setup, and supposedly were able to run 11:1 compression ratio on 87 octane fuel.

SpeedoMotive sells a kit if you really are interested.
http://www.speedomotive.com/ps-105-1...roker-kit.aspx

If i could find my magazine id try to get some more facts from it.
While it is generally agreed long rod kits help a restricted engine flow more air, I would opt for a larger cubic inch stroker to increase torque. The longer rod increases dwell time at TDC an BDC resulting in quicker piston speed mid-stroke improving cylinder filling. However, the larger cid strokers almost always produce more torque.

This particular kit is a carry-over form the old days before the availabilty of inexpensive imported cranks and rods made the extra labor cost of machining OE parts uncompetitive. However, we cater to custom engine builders willing to try combinations out of the ordinary.

Let me know if you have any suggestions.
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Old 12-28-2008, 01:32 PM   #14 (permalink)
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Hello and welcome to July 2008. FYI today is December 28th.
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Old 12-28-2008, 02:39 PM   #15 (permalink)
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Hello and welcome to July 2008. FYI today is December 28th.
They probably googled there named and this thread came up. Dont be a douche to a good vendor just trying to provide some feedback on one of there products.
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Old 12-28-2008, 03:44 PM   #16 (permalink)
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They probably googled there named and this thread came up. Dont be a douche to a good vendor just trying to provide some feedback on one of there products.
NO yellow star as far as I can see
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