351W short block combo...

[V-8]

Hi guys;
I decide to use:
Late model 351w standard block,Ross special order forged pistons 1/16 1/16 3/16-wrist pin-11.0:1 comp ratio,Lunati 6.200 lenght H-beam rods,Scat 4340 series forged steel crank (3.50 stroke),main girdle with ARP bolts,Lunati piston rings,Clevite bearings.
Others: Holley 750hp series carb,TFS tw heads,Victor jr intake,Hedman headers,Comp Cams mech roller 0.050>242-248/608-614lift/110lsa...
Q:which hp can this short block combination handle?
Q:Can stock 351w block work fine with that combo?

[blykins]

Can I ask a quick question? Why did you use such a long rod with such a short stroke?

Let me run this through Desktop Dyno and see how much hp it will make...

And yes, I would trust a stock block only if you're using 4 bolt mains or the main cap girdle which you specified.

[blykins]

I'm showing about 525hp @ 6000 and 501 lb-ft of torque @ 5000.

[RACER X #99]

I think the CR is too high at 11-1 unless you are running 100 Octane. Best to stay below 10-1 on the street.
Everbody I know who races and has a 10-1 or higher is running race gas.

Is Cam 2 available in Turkey?

Good luck

[blykins]

I'm running 10.5 with aluminum heads on 93 octane....no problems here.....But I agree...11:1 on the street is kinda high.

[brainsboy]

Eleanore,

<<Buy different rods until you check out that they will fit>>

6.2rods on a 350stroke comes out to a 1.77 ratio

As said before anything over 1.54 or so is considered good, going far beyond this standard is really pointless and no major gains will even be seen. but without getting into all of that, and starting a major theory debate.
I dont even know if a 6.2 rod will physicaly fit. It certainly is too long for a 9.2 deck height 351w

As anouther person suggested go with a 6.125 and 302 pistons then you still have a rod ratio of 1.74

[scottj]

Originally posted by brainsboy


Eleanore,

I dont even know if a 6.2 rod will physicaly fit. It certainly is too long for a 9.2 deck height 351w

Brainsboy- What would the compression height need to be for this piston?

[brainsboy]

on a 9.2 deck height you need a 1.25 piston ch


you button is going to be in the ring lands, causing oil consumption.

[scottj]

Well...still say it doesn't fit?

Actually it's a shelf item piston and a 1.250 CH allows .010 for 0 decking The pin is not in the oil ring (not that it would be a problem if it was).

You know how I know?

[brainsboy]

.

[brainsboy]

Scott J,

Maybe this helps,

MY wife wears a size 14 bongo pants. She came to me one day and said she bought a size 8 bongo pants because they were on sale, last pair. Of course she buys at them at 10% off and puts them on a 15% credit card, but I didnt want to start an argument.
I said to her its too small!!!, it wont fit. She said no no no trust me it will fit. Trying to keep a happy marriage I didnt want to argue with her, and said great, hope you like them.
She then ask me to go outside with her, which I did because Im a good husband. She then asked me to hold open her new bongo size 8 pants, which I also did. Then she proceeded to climb up a ladder to the top of our house. The next thing I knew she jumped off roof and dove into the size 8 pants. Now that she actualy had the pants on, I looked at her and saw that the butt was now ripped wide open and all the stiches were 1/2 busted. It reminded me of the HULK, because he to could go from 110lbs to 320lbs and still wear the same pants. Anyhow my wife zipped up her pants and with a pissed off look in her face because she knew I was wrong and she was right said

Well...still say it doesn't fit?

[scottj]

Originally posted by brainsboy


... but without getting into all of that, and starting a major theory debate...

WOW! I think we know why you don't want to debate.

[brainsboy]

scott J,

First of all you didnt win, you have no idea what your talking about saying the button being in the ring land doesnt matter. It causes oil consumption.

Second the top ring needs to be .4 down from the top in race motor or if your using a power adder. with a 1.23 ch piston minus 1/2 you button size .458 leaves .762 for all three rings. then lets but the top ring .4 down from the top for safety, that leaves about .304" inches for the second ring and oil ring, assuming your top ring is only .001 thick, which it is not its 1/16..
So I would suggest you redo your math..

The only way this works is by using a super think oil ring, and running the top ring so close to the top of the pistons you run into others problems. Now why of gods earth would you do this scott?? The answer is for the guy who wants to impress his buddies he has a 433 or 427. At least this excuse has a reason for using this type of a piston. but I cant think of one reason to do it on a 351 with no stroke. Unless you like having oil consumption, or pinched top rings, or many other problems with haveing all the rings with in .762

scott sometimes it better to let people think your a fool then open your mouth and prove it.

[scottj]

V-8- you ask how much power is safe with a stock standard 351W block. Not knowing your application I would say for street\strip with that stroke and compression you will be fine. You obviously know a 6.2 rod will "fit" in a 9.5 deck height block. RacerX has a valid point about compression ratio. What octane do you have in Turkey?

Blykins- Re: "such a long rod with such a short stroke". It is the result of "technology trickle-down". For a high-perf/racing application it wouldn't be considered a long rod. A rod/stroke ratio of 1.8:1 or thereabouts is pretty much the standard today.

A quick look at JE Pistons calalog will reveal that the only piston JE stocks for the 3.5 stroke is for a 6.2 rod. Also, that rod/stroke combination uses a 9.2 deck height to keep from having to use a tall, heavy piston. You will also notice that all the standard shelf pistons for the 9.5 deck stroker combinations use a 6.2 rod as well except for one that uses stock rod length. Note that none of them have the pin in the oil ring land.

http://www.jepistons.com/pdf/2002-je20-23.pdf


Brainsboy- I gain nothing by winning against you.

Originally posted by brainsboy
Now why of gods earth would you do this scott?? The answer is for the guy who wants to impress his buddies he has a 433 or 427. At least this excuse has a reason for using this type of a piston. but I cant think of one reason to do it on a 351 with no stroke.

You brought up racing engines. I refer you to a link you can follow to Robert Yates Racing where you will find 178 sets of rods used in Cup racing. They range in length from 6.2" to 6.4". You will also find 67 crankshafts with strokes ranging from 3.24-3.45". They do not use the pistons you say are required for racing engines. You wouldn't belive me so ask them why they use the piston/ring/rod/stroke combinations that they do. Unless you don't consider these racing engines.

http://www.racepartsdistribution.com/index.htm

[RACER X #99]

Scottj,
Nice comeback without resorting to a putdown.

Cranky

[Jack21]

A few comments and suggtestions on your build:

Unless you can buy 98 - 101 octane gas at the pump, keep the compression around 10:1 aluminum heads, 9.5:1 iron heads.

For a few dollars more at this stage of the build, you can get the 393W stroker kit crank, rods, and pistons. You'll be happier with the extra bottom end tq for a street motor.

Consider a hydraulic roller cam, rather than solids for a potent, yet maintenance free valve train. I'm using the CompCams 224/224-.533/.533 retrofit grind and am quite happy with it. Revs quite eaily to 6200. The trick to valve train stability is to use the valve springs that came with the cam, and send the springs that came on the heads back for credit. And don't forget to swap the distributor gear off for a steel roller cam gear.

Roller cam springs generate a lot of heat. I polymer coated mine with an oil retentive coating to assist with cooling. Would do likewise on piston skirts with an new build. Would also install Total Seal gapless rings with a new build.

Think you'll be way happier with a Demon 750 DP rather than the Holley. If you go stock displacement, use the Demon 650 DP instead.

You should get headers specific for your car/engine combo with the car. Have them ceramic coated inside and out for corrosion protection, and heat reduction.

Good luck.

[brainsboy]

Eleanore,

Talk to some machine shops first, get some second opinions before making your choice. Sometimes we get some people here who want to try and prove a point in rediculous situations.

Anyone with common sence will agree that 6.2rod is going over board in a 3.50 stroke and you will expience other problems that strokers have.

You really should stay away from a 6.2 rod on a stock 351, there is no reason to have the same problems that people have in the stroker motors. Just for your reference, the piston that scott is talking about is a specific piston and rod combo which is used for the Yates head, which are a complete different ball game. Those are inverted pistons.

Infact last time I checked it had the button in the ring lands anyhow.

Better luck next time scotty boy

[V-8]

Hey guys;
What are you thinking about building a 393 stroker?The TFS tw heads feed a 393 stroker?They can get enough for a stroker?

[V-8]

Originally posted by scottj


[b]V-8- you ask how much power is safe with a stock standard 351W block. Not knowing your application I would say for street\strip with that stroke and compression you will be fine. You obviously know a 6.2 rod will "fit" in a 9.5 deck height block. RacerX has a valid point about compression ratio. What octane do you have in Turkey?

Unleaded 92 octane.But i will run with a octane booster, it increase 6 points.

[Jack21]

Can you get Muscle Mustangs & Fast Fords
agazine where you are? They just dyno tested a 393W stroker with about a dozen sets of heads. Look it over.

Standard TFS-TW heads (2.02/1.60) plenty for a 393W. AFR 185 (2.02/1.60) and AFR 205 (2.08/1.60) very competitive with TFS.

The guys are right about the rod length though. For a stock 3.50 stroke street motor, it's a waste of money screwing around with a longer than stock rod. Look at it this way. Every SBF with a 5.7" rod would give its' #1 piston for enough deck height to use a 6" rod that we 351W's get stock.

If you go with the stroker, use whatever rod comes with the kit. Actually, for a warm street stroker motor on a budget, get the Scat cast steel crank, and KB hypereutectic pistons #364 which are specific for the 393. Give the stock forgings a street motor workover (magnaflux, sides ground, big ends ground round, ARP rod bolts, magnafluxed again) rebalanced, and bolted back into the motor. For a 6200 RPM every once in awhile motor, this is plenty. For a 6500 RPM every weekend motor, use the aftermarket rods, and forged pistons.