302 Stroker to 347

[RobotMan 264]

Hey guys. I know this is a 69-70 forum but you guys have been a wealth of knowledge while I’ve been building both my sons 69 Mach’s. I am starting restoration of a 68 Fastback Hyland Green car with a 302. I was thinking of building a 347 stroker for it. I have general motor knowledge but am not educated on detail specs and matching of components. A couple of questions:

1. Thoughts on a 347 stroker? Pros and cons?

2. What would be some decent combination for a mild cam engine with nice daily driver performance. Have a blank canvas but not looking for a hot rod. Somewhere between stock and hot rod. 

Thanks in advance for your input,

Rick

[smh00n 87]

I'm no expert on the subject, but I am building one right now.

I had to buy pistons so the 347 versions were no dearer than 302. And the crank and rods were also not a lot more, especially if the rods come with ARP bolts.

Everything else is the same as a 302 build.

For me, Pro's:

• No replacement for cubic displacement
• A bigger cam will be less lumpy with bigger cubes
• More torque
• Virtually the same cost as a 302 rebuild, just the crank and rod cost
• Set the compression at your will, lots of choices out there for pin height on stoker rods. Mine will hit 10.5 easy
• 8.2" deck means no issues with fitting, different extractors, etc compared to a 9.2" 351
• If I leave the 302 badges on it who's to know? 

Cons;

• Extra $$$ for machining to clearance the block and buy the crank and rods
• My Scat crank has a lot of variation in journal size. Not enough to worry a street motor but too much for decent power. That could have meant more $$$ for grinding and bearings (I bought std bearings with the crank)
• Oil consumption remains to be seen. I am told with oil ring lands the oil is not a problem (the gudgeon pin sits through the oil ring land on a 347).

My combo is a HO roller block, fitted with main studs, windage tray and HP oil pump. In there are Scat cast crank and H beam steel rods with a .927 pin, pistons are Sportsman forged with -4cc bowl. Dart Pro 1 alloy heads - 2.02. 1.60 and 195cc runners, an old Edlebrock Torker single plane manifold (I have an RPM airgap but with Holley Sniper they seem to run lean in the end cylinders) and a shorty set of headers. Cam currently is a Lunati Voodoo @ 223/224 with .550" lift, but today I spoke with the engine guy who said it could use another 15 degree duration and .050" lift so I'll probably go that way; but I want a lopey idle and I'm not worried about spinning it to 6,000rpm most gears. The current cam would be just fine if I wanted to keep it. MSD 6AL & pro billet distributor means it boots up instantly, especially with a hi torque starter. I'm using ARP head studs just because I can and all critical bolts are ARP too.

I'm not chasing power and would be happy with 400 at the flywheel. Depending on what expert you talk to it will make 450-500-550. The biggest issue with the Ford block is at decent power - say 500 or more - they fail and split. I don't want nor can afford that so what ever it makes, it makes (but I did spend another $500 on cleaning the ports up). The Sniper is a big ticket item but I am a convert. It starts everytime hot or cold, no hesitation when cold, timing is integrated with the MSD stuff, gas consumption seems to be good and I can set the idle and when the fans come on from my seat. For what it is, at the price it is, I think it's great. Plus when I install the new motor I change the cubes, the cam type and it will adjust fuel to suit. No going to the dyno for me!

Dollar terms this will owe me somewhere around $5,000 US when done but the only part that is used is the block - everything else is new.

One thing - beware of crate engines. A certain blue coloured brand has been making waves down here for some real dud assemblies. My engine guy has done a lot of value-added stuff; bearing checks on the crank, decking the block to suit compression, checked valve springs, skimmed the heads for flatness, balanced it, and generally taking pride in his work, I doubt a crate engine would see all that effort. Plus, I know exactly what's in it as I bought it and I will screw it all together.

[barnett468 418]

On 12/7/2020 at 11:50 AM, RobotMan said:

1. Thoughts on a 347 stroker? Pros and cons?

2. What would be some decent combination for a mild cam engine with nice daily driver performance. Have a blank canvas but not looking for a hot rod. Somewhere between stock and hot rod. 

Thanks in advance for your input,

Rick

It depends on several factors like what trans and gears you have and if you will be doing a lot of high speed freeway driving vs around town driving etc.

Pros - more power

Cons - bad gas mileage

Mahle pistons, lunati/morel or johnson hydraulic roller lifters, lunati https://www.lunatipower.com/voodoo-hydraulic-roller-cam-ford-351w-302-h-o-262-270.html

or similar howards hydraulic roller cam, howards push rods, 3.25 - 3:43 gears if you have a 3 speed auto, posi if you plan to hammer it hard from a stop, edelbrock big valve heads, hedman elite headers of any length with remflex gaskets, around 9.5 compression, 0 deck the block, felpro "s" intake gaskets, budget eagle rods and crank, arp oil pump drive, blueprinted mellings high volume oil pump, have the block machined for an oil seal, performer rpm intake (air gap if you have hood clearance) or similar in another brand, rollmaster timing chain, scorpion lifters (you need the endurance ones if you use stock steel valve covers, and with that cam you could use a higher ratio arm to get more valve lift. i would break it in with joe gibbs break in oil then switch to a group IV synthetic oil most likely 5/40 or 10/40.

[JET 445 43]

Are you going to start a build thread for it, you could put it in the Garage section.

[RPM 1,190]

Am I the only one who's aware of the state law that requires a 390fe be used for power in a 68 fastback in Highland green?

[Midlife 814]

9 hours ago, RPM said:

Am I the only one who's aware of the state law that requires a 390fe be used for power in a 68 fastback in Highland green?

Yes indeed.  Prosecutors will be violated!

[RobotMan 264]

On 12/10/2020 at 8:23 PM, barnett468 said:

It depends on several factors like what trans and gears you have and if you will be doing a lot of high speed freeway driving vs around town driving etc.

Pros - more power

Cons - bad gas mileage

Mahle pistons, lunati/morel or johnson hydraulic roller lifters, lunati https://www.lunatipower.com/voodoo-hydraulic-roller-cam-ford-351w-302-h-o-262-270.html

or similar howards hydraulic roller cam, howards push rods, 3.25 - 3:43 gears if you have a 3 speed auto, posi if you plan to hammer it hard from a stop, edelbrock big valve heads, hedman elite headers of any length with remflex gaskets, around 9.5 compression, 0 deck the block, felpro "s" intake gaskets, budget eagle rods and crank, arp oil pump drive, blueprinted mellings high volume oil pump, have the block machined for an oil seal, performer rpm intake (air gap if you have hood clearance) or similar in another brand, rollmaster timing chain, scorpion lifters (you need the endurance ones if you use stock steel valve covers, and with that cam you could use a higher ratio arm to get more valve lift. i would break it in with joe gibbs break in oil then switch to a group IV synthetic oil most likely 5/40 or 10/40.

Thanks for the detailed info!

Rick

 

[RobotMan 264]

On 12/12/2020 at 5:31 PM, JET 445 said:

Are you going to start a build thread for it, you could put it in the Garage section.

As suggested, I started a build thread in the garage section of the forum. Thanks for the idea!

[barnett468 418]

On 12/13/2020 at 12:14 PM, RobotMan said:

Thanks for the detailed info!

Rick

 

no problem, hope it helps. lots of people here will have good suggestions.