400 hp would be a LOT of kick. That's BOSS 351 territory. Increasing bore for power is a waste of time and money. Use flat-top pistons, hypereutectic, or forged. Stock rods would be fine for your intended use.

 

Thanks for the input. You don't think it's worth upgrading the rods while I'm at it?

As for 400 HP, I was going by Eddlebrock's site. Though I'm sure they bump the numbers a bit for marketing purposes.

http://www.edelbrock.com/automotive_new/mc/power_package/images/2092graph.jpg

 

Hmmm… The 289HP used the same rod forging as the 260 2V, except a slight buildup for bigger bolts. Later, the BOSS 302 used that same rod. The 351W rod was essentially identical, except for the length. Use premium bolts, call it good. A shop near here used to offer (probably still does) stock rods, magnafluxed, shot peened, and deburred, and certified them to 7000 rpm. So, what kind of racing were you planning? High speed runs to Dairy Queen, perhaps?

 

The 351W rotating assembly is pretty stout. Factory parts will serve you just fine.

The factory low compression comes from large combustion chambers in the heads. Since you're installing aftermarket heads, the factory heads are not an issue. I'm not familiar with your specific heads. But most people shoot for 11:1 static compression with aluminum heads and run just fine on premium pump gas. Of course, your camshaft profile has a lot do to with this as well. A more aggressive cam will create lower compression at lower RPMs and higher compression at higher RPMs. (This is "dynamic compression".)

As a data point for you, I'll say I ordered my 351C camshaft from Bullet. They machined a custom, solid lifter cam for me. What's nice about Bullet is the guy who answered the phone is the guy who machined my cam. If I have any questions, I can just give him a call. As for pistons, I went with Speed Pro hypereutectic. Based on my research, I would recommend staying away from the Keith Black pistons.

As 22GT said, flattop pistons would probably be best. If it's in your budget, go with forged pistons. But hypereutectic pistons should be fine for your purposes. If you need to increase static compression, you can deck the block. That's probably better than running domed pistons.

BTW, that carb it probably a little bigger than you need. Unless you're going to spinning your 351 at 7,000 RPM, a 650 CFM carb is more than adequate.

 

Thanks guys! Very helpful information here.

Klutch, would something like these do the trick?
http://www.summitracing.com/parts/slp-h336cp/overview/make/ford

 

Thanks guys! Very helpful information here.

Klutch, would something like these do the trick?
http://www.summitracing.com/parts/slp-h336cp/overview/make/ford

Those are good pistons. But I don't think you'll need those gigantic valve reliefs. Again, I'm not familiar with your cylinder heads, so I don't really know. I built a '69 351W years ago. I used the factory, closed chambered heads with cast flattop pistons. Those pistons had very small valve reliefs and had no problems with interference.

 

Thanks Klutch!

Maybe something like these would be better.
http://www.summitracing.com/parts/slp-h146cl/overview/make/ford

I'll reach out to the company I purchased the heads from to see what they think.

 

I would be very careful buying ebay heads..No doubt they are very poor quality..As for the rods the stock truck rods are fairly good pieces but again watch your price of having them reconditioned vs an eagle or scat I beam rod..The last pistons you listed were for a stroker combination and won't work with a stock stroke..I would look for pistons that will give you at least 9.5:1 compression with whatever heads you decide on...I would get the heads first and then buy the pistons that you need afterwards..

 

Looks like both sets of pistons I posted were actually for strokers now that I look closer.

I already have the heads. I did some research and they ebay store got really good reviews. We'll find out soon enough...

 

jaystang, are you going to have your block machined? It's a good idea to talk to your machinist before ordering pistons. I would recommend you at least have the block and crankshaft checked out by a good, local machine shop. They may have to bore the cylinders to make sure they are true. You'll need to know what size bore is required to get the correct sized pistons. And most machinists won't bore the block until they can mic the pistons.

Your machine shop will also likely have to install your new pistons on your connecting rods. While it's possible to do this without a press, it's not easy. And having a machine shop install the pistons on the rods is not very expensive.

 

Yep, I'm going to bring the block in soon for hot tanking and I will have them check everything out. I'll hold off on purchasing anything until I speak with them.

 

FYI, most shops no longer hot tank. Too many EPA hassles with all the caustic chemicals. Most shops now "bake" an engine block in a very hot oven. I don't think it's quite as effective as a hot tank, but it works. You may get lucky and find your local shop still has a hot tank.

 

I'd go with ARP fasteners on your stock rods and KB-151-020 or 030, depending on how much clean-up is needed to the cylinder bores. You'll also want your rods reconditioned to make sure the big end is truly round. Have the crank checked and if it doesn't need to be ground then just have the journals polished.

 

Thanks bartl.

Klutch, you mentioned staying away from Keith Black pistons. Any specific reason? Bartl, is there a reason you prefer them?

 

Thanks bartl.

Klutch, you mentioned staying away from Keith Black pistons. Any specific reason? Bartl, is there a reason you prefer them?

My research indicated the KB pistons are made in Asia. I also saw multiple comments online from people who used them and were not happy. So, while I don't have any first hand experience, the information I saw about them was not positive. Sure, you'll find negative comments about any product. But you tend to find trends about such things. And the trends for KB pistons were mostly negative.

If bartl has used KB pistons and found them to be good hardware, you should probably put more stock into his opinion than mine.

 

Have you already purchased those parts or is that what you're PLANNING to purchase?

You really need to find out your head specs (minimum - combustion chamber volume, hopefully flow #'s) and then match the pistons to achieve the desired static compression and the cam to the desired dynamic compression ratio - build an engine with about 7.5-8:1 dynamic for cheap pump gas and 8.5-9:1 with good premium pump gas and keep the cam on the milder side you'll be real happy with the street performance as it's the torque off the line that most people feel when they say an engine has "kick" - if you can build 400 Ft-lb torque at 1200 RPM you'll have an engine that is more fun than say one that makes 500 hp at 7800 RPM and only 120 ft-lb at 1200...

Haven't looked in a while but from what I remember most of the Edelbrock cams are a pretty old lobe design that aren't as agressive as a newer profile that will maximize lift/flow/power for a specific duration

 

I have most of the parts (heads included). I started this project 5 or 6 years ago and it's all been sitting for a while and I'm just starting to pick it up again now.

I'll reach out to the seller of the heads to try to get more specifications.

 

If I were you I'd take those heads to a reputable shop and have them checked out as well as have a proper valve job done on them. Those Chinese heads are notorious for having poor valve jobs and bad valve guides as well as seats that fall out of the head. I'd replace the rocker arm studs with ARP studs and swap the valve springs/retainers/locks for a set to match your camshaft you run. Better yet, I think that you would be money ahead to sell those heads and pick up a quality set of heads. You will need a fairly stout camshaft to reach 400hp with your current heads.

I've got a lightly used set of Probe forged pistons and Eagle SIR rods for sale from my old engine I'm parting out. I'll pm you with the details. They would work well with what you are trying to accomplish and are high quality.

 

The KB hyper pistons have a bad rap because people do not follow the instructions for the proper ring gap.If you run a "normal" ring gap it will likely break the top edge of the piston...They are just fine if you use the correct gap. .I am running KB forged pistons in my 408 with no problems so far...