Anybody here ever build one of those 451" strokers?

[wLc]

If so what is your opinion of them? Are they streetable? I have a 400 block and I'm thinking about building one.

[morepower]

yes thier streetabe..think of them as a 440 in a 383 clothes..and cam choice, stall converter and gears, cyl. head flow...decide if a car is streetable or not...i would deffinately build one.

[Chryco Psycho]

they are a nice package

[Deano]

wLc,
I had one built for my 69 Charger this spring and love it.
74 400 block bored to 4.375
Had the 440 crank mains cut to the 400 specs and had counterweights cut to 7.200
Used Mopar 509 cam
Had stock 902 heads bowls cut, pocketed and ported w/ stock valves.
Eddy performer rpm intake
750 Carter competition carb
arp rods
Ross pistons
Windage tray
Accell electronic ignition system.
1 7/8 hooker comp headers
Thats the majority of the major parts. 2800 stall with 4.10s
Currently the compression is 9:1 due to the large chambers on the heads 92cc. I would have them cut down, but by the time i got dun with cutting the heads and bigger valves, I could have bought a set of Eddy's.
I have no complaints as far as streetability

Two things I would do differently:
1) I am going to afford (somehow) a set of Eddy heads.
2) Comp cams high energy cams. I heard about them too late in my build. Some say the car will idle better than the 509 with the same or better power? It's here say for me, Chryco will be able to answer this better than I can.
As far os lope, it lopes like a 440 with a MP 484 cam if that helps.
Other than that it's awesome no problems, winds up very fast, hard to believe it's a big block!
Hope this helps,
                          Deano

[Runner]

i love mine,  its a .040 over 400. true 10.1 compresion 750 dp STOCK 906 heads and a xe282s solid lifter cam, the heads have a good valve job, and good double springs.        it idles nicer than my 383 with a 484 cam did and makes a but load more power.   ive ran a best of 11.80 @ 113.5 mph.  it has 11 inches of vacuum.    i havent done any tuning on it yet and i havent got to race it in good air yet either.  id like to put som e-heads on it and see if i can get it down to the 11.50  range so its right at the nhra-ihra bar rule.   

   great combos!

[wLc]

Hey thanks guys. That sounds like the way to go. If anybody else has any experience with them good or bad feel free to chime in I'd like to hear as many pros and cons as possible.

[Runner]

the only 2 cons you will hear are,  the intake selection is for the lowdeck and becasue the runners ar shorter they dont tend to be qite as good as an rb.  and the added cost of the crank work.  other than that its all positives, better engine fitment, more room for headers,  suposedly a more stable block ( becasue of the shorter deck height).

 

[471_Magnum]

451 is a good combo. I ran one for a while.

What is the intended use? What's your budget? What's your performance goal? What parts do you have to work with already?

Lots of options for building strokers. The 451 is pretty much the most basic.

If you're planning to upgrade to aftermarket rods, you may as well offset grind the crank for a few more inches (~470 cu inches).

Or you can go hog wild and buy a stroker crank.

If you are planning to use factory cast iron heads, you need to watch your compression ratio. The additional stroke can put you over the limit for pump gas real quick.

[wLc]

I'm just planning on running on the street with an occasional trip down the track and I want to be able to take out an LS-1 or two. I have a very limited budget but I'm not in a big hurry to build. I pretty much just want the basic stroker nothing fancy, and nothing too exotic. I have an old block that has been sitting in my barn for years I had thought about building a stroker out of it a few days ago. Here's what I have.

[IBsmokin]

My friend wrote about the 451

the mini-stroker 451 is a gem

You have a shorter, lighter, block.  Now you machine the 440 crank main journals to work in the 400.  The cranks are about the same weight....  You then choose whether you want a torque monster or a higher revving engine -  400 rod = more torque.  440 rod = more hp at higher RPM (negligable difference though, you might not even notice)...  I usuallly recommend the 400 rods as these babies are usually grandma cars and have not been beat on.... Less stress.  The neat part is when you purchase your pistons.....  THEY ARE WAY SHORTER THAN THE 440 or stock 400's BECAUSE YOU HAVE LENGTHENED THE STROKE IN A LOWER DECK - THEY ARE 3/4 INCH SHORTER - AND THEY WEIGH ABOUT 12 oz apiece LESS....  That's where the power comes from....  Take a 12 oz tack hammer and swing it back and forth - drive a nail, but count the hits - or just hit a block....  NOW TAKE A TWO POUND HAND MAUL AND HAMMER AS QUICKLY AS YOU CAN THE SAME NUMBER OF STROKES...  Bet you get the picture then...  These things rev like a 302 Chevy Z-28 when properly balanced and all, and make nearly twice the horsepower with decent (notice I didn't say great) heads....

It's a question of releasing potential energy....  Remember physics 101?
I would use a circa 1973 - 76 400 two barrel engine as they would be the ones with little use and very little hard use....  Stay away from police units or HP engines as you know what they were used for....  The blocks, rods, etc. are the same, only the cams and valve springs, intake, and exhaust manifolds are different and you're not gonna use any of that stuff.

The head castings to look for end in "452" or "1213"....  These are great heads - a competent machine shop can do a great three angle valve job, takin the third angle as far as the fixture will go (free porting).  Install 2.14 intake valves (Back cut units since you have to purchase them) and 1.81 (back cut again, but DON'T LET ANYONE TALK YOU INTO 1.88's////) exhaust valves.  Get springs that match the cam you choose - I would choose the Mopar Performance .509 purple shaft (race version) with292 duration, and put it in 4 degrees advanced with a double roller timing set.

Depending on hood clearance and willingness to use a scoop, the M-1 it the best, but quite tall, often requiring mods in the hood or the addition of a scoop.  At least an 850 CFM carb.  The 870 Street Avenger from Holley is a vacuum unit and great for street strip action....

YOU WILL HAVE TO RUN AN AUXILIARY ELECTRIC FUEL PUMP when you plan to play as the fuel demand of that engine is such that it will deplete your supply and over tax a manual fuel pump.  With it off on our car, we ran .60 slower in the quarter....  That's a ton....  The car felt flat above about 4700 RPM....  Turn the Holley red pump on and BANG - you were good to the redline and beyond....

EXAMPLE ENGINE:  400 Block, 440 craml cut to 400 main journal size, 400 rods (you can use 440 rods and come up with a better rod ratio, but unless you buy new, the 400 is a better way to go - it also makes more torque), .040 over bore, KB Hypereutectic pistons, (be sure to gap the top ring at  .032 to .034 - sounds big, but it is necessary), do not use second ring.  MP .509 cam with 292 duration, 452 casting heads with 2.14/1.81 valve combo, a good intake, an 800 CFM or larger double pumper carb

[471_Magnum]

With the 471, you get all of the above listed benefits of the 451, plus more displacement and even lower reciprocating mass.

Cost is the only real disadvantage. The 471 requires aftermarket rods and works best with aftermarket aluminum heads (due to resulting 10.6:1 compression ratio).

If you are building your 451 with aftermarket rods and heads though, the additional cost of the 471 is minimal. The BBC rods are less expensive than the Mopar rods and this offsets much of the cost of the offset grind on the crank.

With regards to rods, the advent of lower cost H-beam forgings (Cat, Scat, Eagle) in the last few years has made using reconditioned 30 year old stock forgings less appealing. $200 buys BBC H-beams. You’ll be hard pressed to properly recondition stock rods for much less.

It’s pretty much the same story with the heads. The out-of-box performance of the $1300 Edelbrock heads makes investing much into stock castings seem foolish.

For these reasons, I think the 451 set-up is no longer the engine builders’ favorite that it was just a few years ago. Furthermore, monster displacement stroker motors have become so common these days, “451-inch stroker” just doesn’t sound quite as impressive as it once did… not unless you’re talking about a small block.

[wLc]

Is the 471 as streetable as the 451? That is my highest priority streetability.

[Lostsheep]

wLc, those pics are all grainy like the Blair Witch Project.

[471_Magnum]

Is the 471 as streetable as the 451? That is my highest priority streetability.

Just don't build it like listed by IBsmokin. That's a race motor. See the other stroker motor thread in this forum for my recipe. It is plenty streetable. Mine was built as a killer street motor from the get-go.

[wLc]

wLc, those pics are all grainy like the Blair Witch Project.

Cameraphone.

[Ghoste]

We may need to get the old "proven engine combo" forum up and running again as this site grows.  As mentioned in the other stroker thread going on, I've ridden in 471's car and it is a very streetable, very strong combo.  It is definitely a worthwhile recipe to consider for a street sweeper.

[wLc]

I have about decided on the 471.

[Lostsheep]

I have about decided on the 471.