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Discussion Starter #1
Hey guys I have what should be a simple quetion. I have a 90 somethingn 351 F4te rolller motor that I want to build. (never built a motor before. Its going to be stroked to 408. I a piecing everything together. I have a Scot crank already and am looking at getting these pistons. (1969-1976 ford 351W 5.8 sealed power piston set 416P.060) yes the block is 60 over. my concern as a first time builder. is the listing says 69-76 as the years. Can I use this on my motor?
 

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First, the block before it is machined is one of the cheapest parts of a 351w stroker build. Find a good standard bore block to get started. As far as the rotating assembly, nothing will be stock 351w. To figure things out, 351w's have a deck height of roughly 9.5 inches except for blocks from 69-71 or 72 they have 9.480. To get to that deck height take the stroke of your crank, divide by 2, add the length of the rod, center to center, add the compression height of the piston and that should be close to the deck height. The machine shop can make the final adjustments to get the deck clearance needed.
 

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Because the 408 crank has a longer stroke than stock (4" vs the 351w's 3.50") stock 351w pin height pistons will not work.

The rod lengths (and rod bearings) needed will be different too. The most common rod length used is 6.200" and it will have "chevy" sized rod bearings (which is what the 408 crank will be set up for already.) Once the rod length is known THEN you need to select the pistons based upon pin height and the compression desired.

I suggest that before you spend another dime that you study what is commonly used in the available aftermarket kits to become more familiar with what it takes in order to install that crank. Maybe get someone who is more experienced to help make a selection. Don't go into this blindly. Once all the parts are gathered up they will need to be taken to the machine shop so that they can be "balanced" to work properly together.
 

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Why not sell your current crank and buy a complete kit- crank, rods, pistons, etc- that way you know for sure it'll work. Don't forget you'll need to notch the bores for rod clearance....
 

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Discussion Starter #6 (Edited)
Wow,,,,, I was simply expecting a yea that will work or no that wont work, but you all have given me some great advice I have done a lot of research gt350, that isnt a bad idea. Dennis appreciate the insight. I have had the block machined already and I was aware that the rods needed to be 6.2. Howeer I never really understood about the pin height. Mutang I already have the block it is 60 over but i was told a 351w can handle a 60 over bore.
Additionally I hve been looking, a year ago a 351 block was easy to find now they are becoming more scarce. I already have one block taking up space in my garage i dont want 2
I think mutang recommended a std bore,,,, but doesnt the overbore give a few extra cubes,, at 60 over i believe the math works out to a 410 instead of 408
 

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- Contrary to what people say, there are many, many blocks bored .060 over running just fine. My 351 Cleveland is bored .060 and, oh my gosh, it's a thin wall casting! But guess what, it runs too cold. (I need to swap the 180 thermostat for a 190. Cleveland thermostats are hard to find and a 180 is what I found.) My personal theory is whenever someone rebuilds an engine bored more than .030 over, and they experience overheating issues, they immediately think, "It's bored to big!" without considering the myriad of other things which could be causing it; primarily an old, clogged radiator.

- While I've never built a stroker engine myself, I do know that parts matching is critical. This is one of those situations where a complete kit is almost essential. Hopefully, you won't have to sell your crank. I would suggest talking to a local machine shop and asking them to order the parts for you. In my experience, machine shops are happy to spec out and order parts for you. Unlike machining, ordering parts makes them money with very little work. :) Likely, the shop can help you order a set of rods and pistons that will work for your crank and block. When the parts come in, you can have the shop balance the entire rotating assembly; more incentive for them to help you.

- If you haven't purchased a cam, I would strongly suggest going custom. FWIW, I ordered my custom cam from Bullet cams and I highly recommend them. Those guys know cams!

Have fun!
 

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Why not sell your current crank and buy a complete kit- crank, rods, pistons, etc- that way you know for sure it'll work. Don't forget you'll need to notch the bores for rod clearance....
I bought a complete kit for my 347 build--took a lot of guess workout of it. Took it all the shop and had it balanced. The notching is not a big deal at all--I did it in about an hour with the hand die grinder.
 

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Discussion Starter #9
Alright guys I have taken all of the information given here, an trie to make the best decision possible. Instea of selling m crank. I looked at the scat components for the stroker motor. I just bought this.
SB Ford 351W/408/427 Scat Pro I-Beam Connecting Rods 6.200 Length 7/16 ARP Bolts.

They come notched for stroker motors. I also realized that Scat doesnt sell pistons so I am looking at these.

DSS Piston Set 8763-4060; E-Series 4.060" Bore -18cc Dish for Ford 351W Stroker
Prices work out and i dont have to buy the pistons today i can wait a few weeks.
Now i have to research -18cc pistons ebay says it is 10.54CR with 61cc cylinder heads. my heads are 58cc.
They also have flat top pistons too so I have to figure out what is best. If I remember correctly with my AFR 185 heads I want to stay below 11CR.
 

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Wait! Are you saying that the cylinders are ALREADY bored to 4.060" without first obtaining and fitting the pistons??? Or are you saying the cylinders are such that it will NEED to be bored oversize to be serviceable?
 

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Discussion Starter #11
I am saying i bought the block with a 60 over bore, I went to the machine shop and had them magnaflux and check the block and make sure that everything was ok with the block. They measured the block and confirmed that it was 60 over
 

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I know you have already purchased some of the parts, but I just wanted to toss this in. I purchased the Eagle Street and Strip Rotating Assemblies 16525060 for my motor and then had to send it out for balancing. With my 69 block, I did not need to notch the block. The 351w stroked to 408ci @ .060 over, comes up to 414ci.

 

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Discussion Starter #13
69 thanks that helps allot. Not that it matters but how much hp are you getting. Also this kit comes with 6.5c piston head volume, how would that change with my -18 dish. I hae the F4te block
 

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You always buy the pistons, then bore and hone the block to the correct wall clearance for those pistons. If you're already .060 over, you may end up not being able to attain a proper wall clearance with a .060 over piston. If it was .030 over it wouldn't be a problem, you'd just get a .040 over piston and machine for that. But there is nowhere to go after .060.
 

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Doc67, if your block was bored BEFORE you bought the pistons, whomever sold you the block did you a disservice. One is supposed to have the pistons in your hands, measure them, THEN bore and hone. Not everybodys 060 piston is the same outside size. Yes, they'll all be close, but if you find the fit is too tight, you can hone the block some more. If however, the fit is too loose, you have more of a problem. If you buy the pistons and the fit is looser than ideal, let us know and I'll tell you what your options are. At the shop I retired from, the block operator WILL NOT bore your block until she has the pistons in her fingers. She wants to measure the pistons with the same gauge used to setup the boring bar and the hone. We HAVE fixed a 'too loose' problem created by other shops before. Let us know how it measures out. LSG
 

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i think the is a over reaction to the piston bore issue. pistons are commonly replaced on a regular basis in race motors without any hone work done. so anytime a guy has a piston damaged from nitrous or boost you think they tear the whole block down and rehone it ? hell no they dont. people replace pistons seasonally or sooner. is it a smart practice, sure. but it is not the end of a engine build lol.
 

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how i see it, this guy is just trying to throw a engine together, as long as the pistons are the correct overbore he will be just fine
 

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Discussion Starter #18
Once again this site does not dissappoint. JDUB had me nervous last night but then i realized i should be ok. The actual parts that I have bought should be universal. Like I said I took the block to the machine shop and they measured and said i was ok. However i bought the crank which doesnt depend on bore, and I bought the matchingn connecting rods whch doesnt depend on overbore. When I get the pistons I will take them to the shop an its a win win. if they fit ( which they should) then i am Golden.If they dont fit I can send the pistons back and get 30 oer and find another block.
As you guys can see im optimistic and I always try to find the good in a situation.
This will be a street car, i will "never race" ;););)
 

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The pistons will fit but what I think others are referring to is the piston clearance could be to great. Was the block already finished honed? Was the block used and driven with the .060 bore? If the clearance is to great you could have a slight piston slap until the engine warms up.
 

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Hey guys I have what should be a simple quetion. I have a 90 somethingn 351 F4te rolller motor that I want to build. (never built a motor before. Its going to be stroked to 408. I a piecing everything together. I have a Scot crank already and am looking at getting these pistons. (1969-1976 ford 351W 5.8 sealed power piston set 416P.060) yes the block is 60 over. my concern as a first time builder. is the listing says 69-76 as the years. Can I use this on my motor?
If you’re doing the work yourself, start a Build Thread in the Build Forum, I’d like to follow!
 
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