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V-8 12-19-2003 01:52 PM

351w hp capacity
 
Hi guys;
What is the hp capacity of standard 351w block,crank and rod? Thanks...

turnpike boy 12-19-2003 02:06 PM

...just about the same capacity of your bankbook.

:)

V-8 12-19-2003 02:22 PM

I know budget is so important, but im talking about standard parts.

DAVID GAGNARD 12-19-2003 02:38 PM

V-8;

I don't know,but I have a buddy running a 377 stroker putting out approx. 435hp.... Using a stock offset ground crank and an early 70's block.... Motor has about 20,000 miles on it and I'd guess at least half were put a quarter mile at a time on NHRA tracks.... He shifts at 6,000 rpms and has a 6200 rpm chip in his MSD box,it still together and actually never been apart....

The 351 block is pretty tough as are the crank and rods.... I would use the crank,but for anything over 400 hp I'd feel better with aftermarket rods....My guess is the block could safely support 500hp all day as I've seen a lot of 392 strokers putting out that number and some are raced pretty hard....

David

brainsboy 01-06-2004 01:54 PM

I had a 71 datsun I built with a 1969 351w block, a 6-71 blower running 10lbs boost, with stock crank and rods, I was running around 565 horsepower, shifting at 7K rpms. 10.71 @ 127mph in the quarter mile. I never had a problem with the bottom end. However most of the people I had spoke to said dont run more then 550hp on the stock parts. I was a little bit in the grey area, but never had a problem with it none the less. I ran it that way for about 6 years. If your under 500hp the stock rods are more then enough, just have them magnafluxed and stress relieved.

V-8 01-07-2004 03:34 AM

Quote:

Originally posted by brainsboy


I had a 71 datsun I built with a 1969 351w block, a 6-71 blower running 10lbs boost, with stock crank and rods, I was running around 565 horsepower, shifting at 7K rpms. 10.71 @ 127mph in the quarter mile. I never had a problem with the bottom end. However most of the people I had spoke to said dont run more then 550hp on the stock parts. I was a little bit in the grey area, but never had a problem with it none the less. I ran it that way for about 6 years. If your under 500hp the stock rods are more then enough, just have them magnafluxed and stress relieved.
Main girdle is good for strength the bottom end?

brainsboy 01-07-2004 11:46 AM

Eleanor,

That motors short block was on a budget since all the money was thrown into the blower setup. I didnt use a girdle or anything special on the short block other then ARP rod bolts and main bolts, my goal was only for a 500 to 525hp motor and I ended up with about 565hp.

I saw your posts about the 6.2 rods, just curious how much HP are you looking for. In order for us to help you more, give us some more details about what your trying to do, budget, hp, street, strip, weekend driver, ect.

V-8 01-07-2004 01:58 PM

http://www.otospor.com/cowboys/67mustang.htm
http://vipspeed.com/cars.htm
I had changed some parts with:3.55 richmond,TH-350 trans with TCI swap kit,bore 0.030,750hp series carb holley,car weight 3222 with me,x-pipe,Comp Cams xtreme mech roller #35-771-8 .Lift 608-614,lsa 110,0.050 242-248.XR280R.
Max shift point 6500rpm,redline 6800rpm
It is a street/strip car.Now my car at the work shop.Im planing to do in my new project:TFS heads port polish and o-ring groove,stud and main girdle,lunati h beam rods 6.200 lenght,lunati special order piston 1/16 1/16 3/16 ,11.0:1 comp ratio,msd 6al,msd retard kit,shot 150 plate nos with alcohol,all ARP studs,lunati rings,windage tray.I wish 450-470hp flywheel and 150hp nos.But i don't know can stock 351w crank and block tolerate 600hp~???Please give me ideas.Thanks,ATAY.

Mr.Fixit 01-07-2004 02:01 PM

We (shop i used to work for, but no longer) used to warantee 351W (strokers) that made over 500lb/ft 500 hp and they all had stock 2 bolt blocks, no girdles, factory main caps.

V-8 01-07-2004 02:27 PM

stock 351w crank tolerate 600hp~?

Mr.Fixit 01-07-2004 03:16 PM

I wouldn't trust it to. Some people may be lucky and get away with it, historically, I am never that lucky.

brainsboy 01-07-2004 03:30 PM

Eleanor,

When I built my motor It was a different situation, I had 3, 351 short blocks sitting around, so I did cheap bottom rebuild, slapped on some nice heads, and 6-71 dyers blower, so if the bottom end crapped out, I really wasnt out much money. To be honest ,with as hard as I ran it, Im a little suprised it kept together at 565hp.

I wouldnt chance pushing 600hp. Sounds to me like your building a nice motor, and investing a few bucks in some nice parts, I would buy a good aftermarket crank. Then you can always build for more power later.

V-8 01-07-2004 03:43 PM

Can you give address or web sites.Which crank is the best?

MidOHasp 01-08-2004 07:10 PM

Scat and Eagle make good cranks. Once you pick a good 4340 forged crank, the price differentials will be based on the finish work on the counterweights. I've heard reports that with a good forged bottom end, you can knock these guys up over 600HP no problem. Girdle the mains and make sure your machine work is done well, you can probably go upwards of 700+hp.

We're running 508 flywheel HP at 6,000 RPM and are going to put in the 6500 chip because 6K just doesn't sound sweet enough. If our valve springs could hold up, it'd probably be safe to 7K+ RPM.

From reading the success stories and the failure stories, I wouldn't go much over 500HP with pretty much stock parts. Get a good Eagle or Scat forged crank and even some H-Beam forged rods and pistons and you can do whatever you want.

JP

V-8 01-08-2004 07:50 PM

What are you thinking about stock 351w block?What is the hp capacity of it?

MidOHasp 01-08-2004 08:19 PM

2 bolt mains, stock block, probably right around 600 HP depending on revs. I don't think you can go too wrong w/ a stock block at 600HP, 6K RPM. That's easy. You can probably up one of those to a 7, maybe even both, but then you probably need to start thinking about girdling the mains.

Earlier you mentioned standard/stock parts, and I wouldn't say you can go that high. But with aftermarket rotating assembly, the block is tough and can hold up pretty well.

Reading what you're talking about - 6800RPM, NOS, etc...You'd be smart to go with the forged crank. Block will probably hold up fine. I'm not an engine builder, but I've talked to a lot of them, and a for a stock 2-bolt 351W, these guys say my 508HP is "pretty mild and pretty much bulletproof".

Ultimately, an extra grand in "solidification" can be a cheap insurance policy.

Perf. Eng. Eric 01-08-2004 10:01 PM

We build stock stroke Windsors that dyno out at 480 HP. We use ARP studs on the mains. We also build a 418 stroker Windsor that develops 550 to 580 HP ( depending on cam chioce) . On the stroker we have been using a main cap girdle. As far as the stock stroke Windsor crankshafts, the Scat cast- steel works great for us with no problems. I would go with the the H- beam rods and forged pistons. Hope this helps.


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