I went with a DSS kit for my 331.  Mine uses 28 oz balance. 

It all depends on what you want it to do.  I seem to remember previous threads about wanting 350HP, which isn't going to be hard at all with a 331.  You can stick with a cast crank.  Regular rods will be okay too so long as they have ARP bolts or capscrews.  I would always opt for forged pistons, just because they are more forgiving if the tune up is off.  The one thing I look for in a stroker kit is to keep the rods as long as possible.  Engines with a better rod/stroke ratio accelerate better.  Ideally you want 1:6 or above, which is tough given the deck height on a 5.0. 

Keep in mind that strokers are going to require clearancing too.  Minimally you'll have to clearance the oil pan rails, but the cheaper kits may also require things like a reduced base circle cam to avoid running the cam lobes into the tops of the rod bolts (capscrew rods don't have this issue).  Most machine shops will be able to clearance the block based on past experience.  Other clearances you should check during assembly. 
 

I bought a pretty basic Scat kit with cast steel crank, I-beam cap screw rods and forged pistons. All quality USA parts, bearings, etc. including ARP rod bolts. The Scat kits are a good value I think.

TKOPerformance wrote:

I would not run a stock GT cam.  Its a series of too many compromises.  A new cam will probably find you more low end and mid range with no loss in idle quality and still make better power up top.  I wouldn't go to the trouble to build a stroker then saddle it with 30 year old cam technology.  Especially if you are going to run a carb instead of EFI (tighten up the LSA). 

what Cam do you recommend  .....its gonna be mostly a driver and some long distance trips.
The base engine is a 98 explorer engine with the GT40p heads, Performer intake and 570 avenger Holley carb, it has Hi-Po exhaust mainifolds
. It has a 3:00 rear gear at the moment and I will change it eventually maybe to a 3;25 or 3;55
 

Last edited by BILLY WALTON from GEORGIA (7/03/2022 11:39 PM)

Bread used to be 25 cents a loaf, every thing has gone up in price.

When I had my 331 balanced they wanted the damper, flexplate, all rods, cap screws, pistons and rings.
The torque converter was balanced by the guy that built it, engine runs very smoothly.
My cam is a Comp 35-440-8
Performer RPM intake
Holly 670 Street Avenger carb
Edelbrock heads #60379

Last edited by Rudi (7/04/2022 2:23 PM)

BILLY WALTON from GEORGIA wrote:

anybody seen a basic 331 kit  at a good price....I use to see them under 1000 like 850 to 1000 . I dont need the balancer or fly wheel/flexplate

With the import situation with China, the port situation nationwide, and the cost of all metals having gone up my guess is that engine parts are also being affected.  This would be my suggestion:

https://shop.dssracing.com/331_SX_rotating_kit_p/ra331sxu.htm

Cam recommendation (from 6sally6!)
Duration  230-236@050
       Lift    480-500
       LSA   108*
Get a custom ground cam (the same money or less!)....
instead of a shelf grind that was more than likely designed for a Chevy!
Get NEW roller lifters....make sure the springs are in great shape too.

The idle will be lumpy (NOT snotty) and power will come on 1200RPM (or just above idle)
Power band will start  around 1200RPM and be maxed out by 6000rpm.
(I doubt you will ever take it above 6000 RPM anyway)
It will work right in the range you will drive it.
That extra 30 cu. in. will calm down a snotty idling cam
6s6

I've been eyeing this 347 kit up.  Im going to run the explorer engine that I have with a cam and heads upgrade and see how it runs first.  If Im not happy with it then I might do the stroker kit down the road.

Scat Mustang Stroker Series 9000 347 Cubic Inch Street-Strip Rotating Assembly 1-94165 (79-95 5.0L Mustang) - Free Shipping (americanmuscle.com)

Steve69

Speaking of Scat, the company not the droppings, I was able to get this unused and never removed from the box, Scat forged crank for my brother off FB Marketplace in LA for $400 a couple weeks ago.

Steve69 wrote:

I've been eyeing this 347 kit up.  Im going to run the explorer engine that I have with a cam and heads upgrade and see how it runs first.  If Im not happy with it then I might do the stroker kit down the road.

Scat Mustang Stroker Series 9000 347 Cubic Inch Street-Strip Rotating Assembly 1-94165 (79-95 5.0L Mustang) - Free Shipping (americanmuscle.com)

Steve69

I dont see the 331 kit like that.
 

McStang wrote:

Scat’s kit p/n 1-94055 is what I picked up, all top-quality parts for very reasonable $.

https://lmr.com/item/SCA-194055/Scat-Mustang-331-Stroker-Kit-82-95-Flat-Top-Piston-I-Beam-Ro

https://www.summitracing.com/parts/sca-1-94055

https://www.scatcrankshafts.com/rotating-assemblies/

Thanks so the flat top pistons will work good with the Explorer GT40p heads right?
 

Bearing Bob wrote:

Why trust someone else's word on your time and money. Clay the piston and check for yourself.

Thought you might know.
 

McStang wrote:

The flat tops with this kit have valve reliefs and should be fine butt you really have to check clearances at assembly to make sure all is good.

Thank you I had to get my 11 to 1 pistons fly cut on my old 289 about 30 years ago