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FE Power Forums => Non-FE Discussion Forum => Topic started by: Joey120373 on April 08, 2022, 12:26:46 PM

Title: 347 build for my 64.5 mustang
Post by: Joey120373 on April 08, 2022, 12:26:46 PM
With my FE Power headed 520 on hold for who knows how long.....
Jay's been fighting the covid 2 week " shut down" a full 2 and a half years later.
My block and rotating assembly have been at the machine shop since last june, and it hasn't yet been touched.

I've decided to start on another project for the summer.

Target is 500-530 ish HP, and a high rpm redline.
mustang will be a spirited pump gas daily driver, T56 manual 6 speed, 4.11 rear gears, manual steering and manual brakes.
Weekend cruiser, not a drag car.

So far I have tentatively planned the following group of parts :

Stock roller block, .030 overbore
-I decided against an aftermarket block for now, i would rather put that $$$ else where and save some weight. with the aftermarket block, not sure the extra 16 cubes is worth the extra weight and expense. I know the bigger bore helps with valve shrouding and thicker cylinder walls are always good, but for my power goals I think the extra ~$3000 would be better spent elsewhere.-

Scat rotating assembly ( forged or cast crank ?)
Mahle Flat top pistons (4032 alloy )

AFR 195 or 205cc heads ( 10.5 to 11.0 CR, maybe more, i live at 5400 feet )

Jesel shaft mount rockers

Solid roller cam ( or a hydraulic roller..... )

Intake manifold yet to be decided on.

I want the ability to rev this thing to 7000-7500 rpm, maybe higher.

I know the heads might be on the large side, and the shaft mount rockers are probably overkill, but i want the option to play around with it, rev it higher if i get a wild hair.

Wondering what the experts think of this selection of parts ?
Any advice is appreciated. I have not ordered any parts yet.


Joe
 
Title: Re: 347 build for my 64.5 mustang
Post by: pbf777 on April 08, 2022, 01:45:45 PM
     Lets' see,

"Target is 500-530 ish HP, and a high rpm redline. ............will be a spirited pump gas .............Stock roller block, .030 overbore - I decided against an aftermarket block........... for my power goals I think the extra ~$3000 would be better spent elsewhere.................Solid roller cam...............I want the ability to rev this thing to 7000-7500 rpm, maybe higher............... i want the option to play around with it, rev it higher if i get a wild hair."    :o

     Just don't cry when it breaks!   

"Wondering what the experts think of this selection of parts ?"  ::)

"Any advice is appreciated."  :)

     And I know that I often seem to come across as a 'dick', but I'm really just trying to be honest and accurate; but, I also find that few really appreciate that fact  :( ; but you did ask!   :)   

     Scott.

     


Title: Re: 347 build for my 64.5 mustang
Post by: shady on April 08, 2022, 02:32:39 PM
It's ok to be a dick.  After FElony got banned, it left a lot of room for us amateur dicks.
Title: Re: 347 build for my 64.5 mustang
Post by: shady on April 08, 2022, 02:43:18 PM
worth a look


https://bangshift.com/bangshift1320/the-reasons-that-ford-small-blocks-split-in-half/
Title: Re: 347 build for my 64.5 mustang
Post by: Joe-JDC on April 08, 2022, 03:18:48 PM
For your build, go with Scat forged stroker kit, AFR 165 Renegade heads, Hydraulic roller with short travel lifters, Victor Jr or Super Victor ported, and 1 5/8 to 1 3/4" step headers to fit your chassis, 750 Holley/QF/or similar, Deep sump oil pan with canton windage screen.  Those AFR 165 heads will support 550hp, so don't worry about them being too small.  Joe-JDC
Title: Re: 347 build for my 64.5 mustang
Post by: Tommy-T on April 08, 2022, 03:45:16 PM
Please help me with my perpetual ignorance.

Why not install a 351W instead of a 302 stroker.

If the answer is that the engine is slightly wider and you don't want to "notch" anything for the install into your 64.5...that's silly.

Anything near an actual 500hp motor is going to twist that 1965 Mustang like the proverbial pretzel. I'm ass-u-me there's going to be subframe connectors, a 9" install with all the goodies to hook 500hp and so on.

Sooo...I say cut away...and make that a 393 or 408W stroker.
Title: Re: 347 build for my 64.5 mustang
Post by: frnkeore on April 08, 2022, 04:10:29 PM
While the 351W block, is stronger, I've always liked the 8.206 deck. If you don't already have the block, I'd stay away from the HO blocks and go with the earliest 302 block, that you can find. The blocks I use are C8, C9 & D4, they are stronger. The jury is out on how much strength a girdle adds but, they are cheap and I would add one.
Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 08, 2022, 05:03:10 PM
I've got a couple of 347 recipes based on stock blocks.  One particular 347 made 540 hp here and has been in a bracket car for the past 12 years.  He raced it for 8 years straight until he puked a power valve and wasn't paying attention to it.  Washed the cylinders down, then needed a freshen up.   It was a good thing he brought it back in, the cast Scat crank had cracked. 

So...I would probably do a steel crank, even though the crank would  be rated for a lot more hp than the factory block will take. 

That little engine runs some AFR 185 heads, a fairly mild solid roller, 11:1 compression, and a Super Victor intake.  It makes 540 hp @ 7000.

I also built a nice little 347 with CHI 3V 185cc heads that made about 530 hp @ 6200 with a hydraulic roller and 10:1 compression. 
Title: Re: 347 build for my 64.5 mustang
Post by: Rory428 on April 08, 2022, 06:54:53 PM
I have had both a stock block 331 SBF, and currently have a "big bore" 347, both pump gas usable, flat top pistons, with AFR 185 heads. The 331 made 487 HP, and ran mid to low 10s in the 1/4 mile, for a couple of years before it split the main bearing area of the factory 5.0 roller block. It had a solid flat tappet cam, and never went over 7000 RPM.  My current 347,made 528 HP, has a 4.125" bore Dart block. Both engines used 3.25" stroke cranks, the 331 was a cast Eagle, with 28 oz imbalance, the 347 has an internal balanced steel crank, and a hyd. roller cam, that I shift at 7000 RPM, and hits 7200 across the finish line. Considering the use of a stock block limits you to a 4.03" bore , that means you will be using a 3.4" stroke. With the longer stroke causing more cylinder side loading, and wanting to turn 7500 RPM, makes me doubtful that a stock block will be very long lived, if you actually plan to twist it that high very often.
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 08, 2022, 07:51:14 PM
 @pbf777

“     Just don't cry when it breaks! ”

Won’t cry a bit as long as the heads are ok  8)

On my list of criteria, a 200,000 mile motor is way, way down on the list. If the block breaks, just gives me an excuse to step up to a good block.

Title: Re: 347 build for my 64.5 mustang
Post by: pbf777 on April 08, 2022, 08:41:55 PM
Won’t cry a bit as long as the heads are ok  8)
On my list of criteria, a 200,000 mile motor is way, way down on the list.

     But, it's actually often just called the "luck of the draw"!   ???   As we seem to always hear about so-and-so, who spent ten dollars on a bunch of junk (plus a can of Kylon  ::) ), made a gazillion horsepower, and it ran forever, if you believe it ::), but it does happen, ...............sometimes, but most of the time it shytz the bed in short order and we, Joe Public, aren't made so aware of so-and-so who tried to "skin the cat", but rather the cat got the best of him!   :o

     For example, we had a customer with a brand new "Sportsman" block in a 10 sec. door car get just four 1/4 mile passes before it broke!   :'(  And yes, have also witnessed 'some' others go an amazing distance, though generally on tear-down one finds that they might as well just toss the hole thing in the junk-pile, if one looks close enough,............but it hadn't failed,......... yet.    ::)

     And as for the video of why the S.B.F. cracks in half..............well, that may have been one experience, and that may very well be one theory, but it alone isn't the 'real' issue based on my many observations of failures.   ;)

     Scott.
Title: Re: 347 build for my 64.5 mustang
Post by: WConley on April 08, 2022, 11:31:05 PM
In my book the 530 HP in a stock 5.0 block is not the big problem.  It's spinning a stroker rotating assembly to 7,000 rpm in a stock block.  At those speeds the "inertia load" from the piston/ rod assy on the main bearings vastly exceeds the "combustion load" that makes the horsepower.

If it was me I'd get the aftermarket block for plenty of revs without puckers.
Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 09, 2022, 05:43:51 AM
It is the luck of the draw I think.  The one 347 I mentioned is a 4.040 x 3.400 combo that has been going for years.  He leaves with a clutch dump at 5500 and shifts it at 7000.  It will run in the 6's or the 10's depending on which track he's at.  It uses a mid-80's 302 block.

If you're not willing to buy an aftermarket block right off the bat, see if you can find yourself a real early 302 block, or Mexican 302, etc.  I sold a fully machined Mexican 302 block to Joe Craine a few years ago that he was going to use in an EMC.  He may let it go. 

To add to Bill's point, I would also opt for lightweight rotating assembly components.   Most guys want to reach for the heaviest H-beam rod they can find.  A lot of the I-beam rods will be lighter and still take the punishment, or you can go with a Molnar/K1 rod.  Mahle and CP make some pretty light pistons as well and use the 1mm or 1.5mm rings, which are a ton lighter than some of other offerings out there. 
Title: Re: 347 build for my 64.5 mustang
Post by: frnkeore on April 09, 2022, 12:48:55 PM
Regarding the Mexican block, most all get almost as much as the 271 HP, K code blocks But, if your willing to do the searching, you can find some, in the early '70's PU trucks. I found one in a '71 or '72 PU.
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 09, 2022, 02:39:41 PM
For your build, go with Scat forged stroker kit, AFR 165 Renegade heads, Hydraulic roller with short travel lifters, Victor Jr or Super Victor ported, and 1 5/8 to 1 3/4" step headers to fit your chassis, 750 Holley/QF/or similar, Deep sump oil pan with canton windage screen.  Those AFR 165 heads will support 550hp, so don't worry about them being too small.  Joe-JDC

That’s kinda funny, the combo you suggest is pretty much exactly what I had in mind when I first started thinking about a motor for the mustang. I have since probably watched too many YouTube videos. I quickly decided the 180cc heads offered some room to grow, then I finally settled on the 195 heads. I know the 195cc heads are probably overkill, but they seem to not give up much ( at least at WOT on the dyno ) when compaired to the smaller heads.

I will keep those in mind, I was extremely impressed with those heads when the engine masters crew bolted them up to a 408, expecting them to be “ way to small “ and they kinda stole the show.
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 09, 2022, 02:53:11 PM
In my book the 530 HP in a stock 5.0 block is not the big problem.  It's spinning a stroker rotating assembly to 7,000 rpm in a stock block.  At those speeds the "inertia load" from the piston/ rod assy on the main bearings vastly exceeds the "combustion load" that makes the horsepower.

If it was me I'd get the aftermarket block for plenty of revs without puckers.

Thanks for the input, and I agree, I have always thought that RPM is harder on a motor then how hard the piston happens to be pushing down on the rod.

I also think that a lot of the blocks that are splitting are being used in drag race cars. I think it’s also one of those deals where, if the engine just works, nobody notices it, but when the block splits in two, well then everybody notices it.

I guess I should have pointed this out in my first post, but I know full well I’m flipping a coin using a factory block. No shortage of people who have cracked a block, yet there are also lots of people who run and rev the snot out of a stock block for years and no issues.

Part of the reason I went big on the heads and valve-train is a bit of pre planning if the block does fail .If that happens, or even if it doesn’t and I just wanna play with it, I can take all those parts that are overkill on a 347 and swap them over to a 363 where they aren’t so overkill anymore.

Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 09, 2022, 03:03:44 PM
Please help me with my perpetual ignorance.

Why not install a 351W instead of a 302 stroker.

If the answer is that the engine is slightly wider and you don't want to "notch" anything for the install into your 64.5...that's silly.

Anything near an actual 500hp motor is going to twist that 1965 Mustang like the proverbial pretzel. I'm ass-u-me there's going to be subframe connectors, a 9" install with all the goodies to hook 500hp and so on.

Sooo...I say cut away...and make that a 393 or 408W stroker.

Tommy, your my kinda guy! I have thought about a 351 block a lot, and every time I do, I end up at a 427 or 460 stroker in an aftermarket block, the biggest heads and “Katy bar the doors” .
To me it seems really silly to spend $3000 on an aftermarket 302 block, when the 351 version essentially costs the same and offers another 100 cubes .

But I want to keep it a small engine, I want it to look “right” in the engine bay.

Making 500 hp with a factory 351 based 408 stroker is pretty easy and cheap, and would last forever.
That is the smart way to do it, but I want light weight and high revs. Longevity is not a concern for me.
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 09, 2022, 03:07:05 PM
While the 351W block, is stronger, I've always liked the 8.206 deck. If you don't already have the block, I'd stay away from the HO blocks and go with the earliest 302 block, that you can find. The blocks I use are C8, C9 & D4, they are stronger. The jury is out on how much strength a girdle adds but, they are cheap and I would add one.

I’ve already got the block, and I was going to ask about the girdle. I kinda feel the same way, a girdle may not help, but unless it could hurt in some way, I don’t see a down side to having it.
Title: Re: 347 build for my 64.5 mustang
Post by: Joe-JDC on April 09, 2022, 09:43:02 PM
If you do add a girdle to the mains, make sure it is steel, not aluminum.  Around here the ONLY failures of the blocks were with the aluminum girdles that were supposed to absorb vibrations, but actually grew with the heat and helped split the blocks.  I put a 351W in my 1966 Mustang back in 1972 with 4 speed, and that was one of the best driving cars I have owned.  Plenty of torque, light weight, and would run with the big block crowd all day with ease.  I put a 351W in one of my '66 Fairlanes with 4 speed also, and that was a great daily driver.  Raced a 351W in my '69 Mach I for several years before going to 427, and have a 383W in my '86GT now.  I have a 427 Dart Windsor ready, a 410W ready, and if you ask me what my favorite engine is after all this, then you weren't paying attention.  Joe-JDC
Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 10, 2022, 05:13:39 AM
If you do add a girdle to the mains, make sure it is steel, not aluminum.  Around here the ONLY failures of the blocks were with the aluminum girdles that were supposed to absorb vibrations, but actually grew with the heat and helped split the blocks. 

That's why I say girdles don't do anything.  The 347 that I have mentioned several times in this thread has a DSS aluminum girdle on it.  When I first built the engine, the owner brought the block in with the girdle on it, so I just used it.   It's had 100's and 100's of passes on it. 

I think it's up to the block on whether or not it's going to take a dump.   Just the luck of the draw and a girdle (or lack of) isn't going to change things.
Title: Re: 347 build for my 64.5 mustang
Post by: fekbmax on April 10, 2022, 09:35:24 AM

My block and rotating assembly have been at the machine shop since last june, and it hasn't yet been touched.


Joe


WoW, 10 months in the machine shop and hasn't been touched ? You got way more patience than me.  I thought 6 weeks was to long to leave stuff just setting. 
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 10, 2022, 12:01:11 PM

My block and rotating assembly have been at the machine shop since last june, and it hasn't yet been touched.


Joe

Not casting a bad light on the machine shop, I told him when I dropped it off that I was NOT in a hurry for the motor, as I had a feeling it was going to be a while before I had the heads in hand. So while I was hoping to see some progress after 10 months, I can’t hold it against him. When I checked in a few weeks ago, he said he was waiting for a weekend where he had nothing else going on and no distractions, I am hoping that is the case.
WoW, 10 months in the machine shop and hasn't been touched ? You got way more patience than me.  I thought 6 weeks was to long to leave stuff just setting.
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 10, 2022, 12:42:55 PM
Brent, I am following your new dyno mule build, I do t know how fast you intent to spin that sucker, but the aluminum rods and JE rockers lead me to believe you will be spinning it up there a bit.
I’m guessing you will be using every bit of flow those 180cc heads have to offer.

I may hit you up for a roller cam and lifters for the 347. And I might talk to Joe about working on an intake for me as well.

Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 10, 2022, 01:30:10 PM
Brent, I am following your new dyno mule build, I do t know how fast you intent to spin that sucker, but the aluminum rods and JE rockers lead me to believe you will be spinning it up there a bit.
I’m guessing you will be using every bit of flow those 180cc heads have to offer.

I may hit you up for a roller cam and lifters for the 347. And I might talk to Joe about working on an intake for me as well.

I'm trying some new lobes that I've never tried before, so I'm not 100% convinced on how high it will turn, but the goal is pretty high...

I've done a poop load of SBF/AFR head combos.  I can help on the camshaft for sure.   
Title: Re: 347 build for my 64.5 mustang
Post by: Rory428 on April 10, 2022, 05:37:35 PM
@pbf777

“     Just don't cry when it breaks! ”

Won’t cry a bit as long as the heads are ok  8)

On my list of criteria, a 200,000 mile motor is way, way down on the list. If the block breaks, just gives me an excuse to step up to a good block.
Unfortunately, if the block breaks, there is a real possibility that your reciprocating assembly, as well as the heads, won`t "be OK".
Title: Re: 347 build for my 64.5 mustang
Post by: machoneman on April 11, 2022, 06:57:50 AM
I agree with Rory as if the block splits, it's worse than 50/50 that the heads will take a hit. Agree with Brent on the DSS alum. girdle as I well knew the owners from long ago and had my block work done by them. DSS has sold a ton of those girdles btw.

Still, I never used one in my 351s as I didn't think it was helpful AND early vintage 351W's like mine rarely had main saddles let go. Later 302W's (5.0's) with thinner metal often did have saddle cracks and owners may have found any girdle somewhat helpful but I still doubt their effectiveness over time with hard running of these blocks. 
Title: Re: 347 build for my 64.5 mustang
Post by: pbf777 on April 12, 2022, 10:59:20 AM
Unfortunately, if the block breaks, there is a real possibility that your reciprocating assembly, as well as the heads, won`t "be OK".

     I would not dispute this statement; but generally in the instances of the block splitting in half thru the valley, one has notice prior to the catastrophic separation as generally the cracking begins in the main saddle(s) area, propagates upward into the camshaft tunnel bulkhead, and at that point often the cam bearing retention crush is lost, the bearing shuffles out of position and/or spins and there is a notable loss in oil pressure!   :o

     Of course that is if anyone is paying attention!  ::)  But partly this blame can be at times be laid at the feet of the O.E., as the oil pressure "gauge" mounted in the dash of a Fox Mustang will read "NORMAL" until the oil pressure drops below the switching threshold of something like 5 P.S.I.!    :o

     Scott.
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 28, 2022, 08:56:13 PM
Ok, after thinking on it for a few weeks and taking in all the comments, here is where I am leaning today...... ::) ::)

Stock roller block bored .030 and a 347 stroker kit, Scat crank ( forged or cast, probably forged ) Scat I beam rods, Mahle flat top pistons ( 4032 alloy ) .
AFR 185 or 195cc heads, still waffling on that, I know the 185s are plenty good enough. But I don't think the 195s would be " too big", and the added headroom might come in handy down the road.
 Shooting for 11-1 CR. ( I live at 4500 feet )
Hydraulic Roller cam that peaks power in the 6300-6500 range.
May still do the Jesel shaft mount rockers, mainly because I want to use stock type valve covers, I want the engine to look relatively " stock " .

This combo should easily put me in the ~ 450/450 (tq/hp) range I suspect, depending on what intake I use. 

Brent, I will take you up on the cam offer, I will be in touch.

Title: Re: 347 build for my 64.5 mustang
Post by: Falcon67 on April 29, 2022, 05:01:05 PM
>I think it's up to the block on whether or not it's going to take a dump.

This. Same with an 8" rear - they'll do X until they won't.  Put nearly 1K passes on an 8" until it ate its self.  Replaced with 9" 31 spline parts - no more problems in 20 years.

I've seen stock 302 blocks go year, two in a "small tire" type car with hella spray before they failed.  And I've seen a N/A 347 make 4 passes at low 7s 1/8 mile and fall apart.

I've split many cylinders in 351C blocks.  Won't buy or machine another unless it's for a putt-putt show car.  My spare 302 makes about 300 and is shifted at 5800, no more.  My last stock block 351C makes about 480, limited to 6200.  The new 427 motor - Dart.  Not going to blow $1500+ on machine work for a stock block that may last 20 years or 20 minutes.
Title: Re: 347 build for my 64.5 mustang
Post by: Joey120373 on April 29, 2022, 09:31:16 PM
I keep going back and forth on the aftermarket block issue. I don’t know what the actual weight penalty is on the block, I’ve heard about 60 pounds ? Has anyone actually weighed the two? I have a stock block I could weigh.
Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 30, 2022, 04:25:39 AM
Depends on which block it is.  The Man O' War block is really heavy.  FRPP block is probably the lightest between what's offered now.  I just did a 363 with one but didn't weigh it.  That's another good reason to go with an aftermarket block....free cubes.   A 363 with AFR 185cc heads, Performer RPM Air Gap and a little 220-ish @ .050" hydraulic roller cam will make 500 hp.
Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 30, 2022, 07:26:59 AM
FRPP 8.200" block:

(https://live.staticflickr.com/65535/51566039336_9266ca47f3_z.jpg)

World 8.200" block:

(https://live.staticflickr.com/65535/51738698132_b568808ea2_z.jpg)
Title: Re: 347 build for my 64.5 mustang
Post by: 70tp on April 30, 2022, 11:18:53 AM
Brent: when using the FRPP block with a 3.4” stroke , do you see any problems with the bottom of the cylinders being shorter than some of the other aftermarket blocks?  I’ve been told that the frpp blocks have too short of a cylinder skirt to be reliable long term or can have accelerated piston skirt wear. 
Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 30, 2022, 11:42:22 AM
Brent: when using the FRPP block with a 3.4” stroke , do you see any problems with the bottom of the cylinders being shorter than some of the other aftermarket blocks?  I’ve been told that the frpp blocks have too short of a cylinder skirt to be reliable long term or can have accelerated piston skirt wear.

No sir, haven't seen that.
Title: Re: 347 build for my 64.5 mustang
Post by: Stangman on April 30, 2022, 02:15:24 PM
Looks like more clamping force for heads in the world block and more cooling for the FRPP. Do you have a preference.
Title: Re: 347 build for my 64.5 mustang
Post by: blykins on April 30, 2022, 02:22:26 PM
There's only one head that will bolt up using all the bolt holes on the World block and it's not a head to write home about. 

Cooling has never been an issue, so I can't really say that the bigger holes are a plus. 

One thing I don't like about the FRPP block is that the caps aren't billet and the bolts are just regular bolts (not like ARP).   Now granted, I've made 800 hp with the 9.200" deck BOSS block, so it must not be an issue, but it just doesn't look as professional as the Dart and World blocks. 

FWIW, I haven't seen a Dart block in so long, I've forgotten what they look like.  They haven't been available in about 2 years.
Title: Re: 347 build for my 64.5 mustang
Post by: Heo on May 14, 2022, 04:59:43 PM
There's only one head that will bolt up using all the bolt holes on the World block and it's not a head to write home about. 

Cooling has never been an issue, so I can't really say that the bigger holes are a plus. 

One thing I don't like about the FRPP block is that the caps aren't billet and the bolts are just regular bolts (not like ARP).   Now granted, I've made 800 hp with the 9.200" deck BOSS block, so it must not be an issue, but it just doesn't look as professional as the Dart and World blocks. 

FWIW, I haven't seen a Dart block in so long, I've forgotten what they look like.  They haven't been available in about 2 years.

On my way home now and i stopped over in Stockholm at may friend Ollie. He had just recieved a new Dart block out of the new castings
it was a beauty with realy thick cyl walls.But he have waited one and a half year. Got pics i can download tomorrow
Title: Re: 347 build for my 64.5 mustang
Post by: Rory428 on May 14, 2022, 11:15:23 PM
I weighed both my SBF 331, which used a 1973 production block, and my Dart blocked 347, and the 347 was 35 pounds heavier. Be aware, that these were complete carb to pan engines, and in addition to the differences between the 2 blocks, there were some other pieces that were different between the 2 engines. The 331 had a cast crank, stock timing cover and water pump (aluminum 5.0 Mustang pump), Victor Jr. intake and Comp steel roller rockers, where the 347 has a steel crank, a Jesel timing belt drive and Meziere electric water pump, and a Parker Funnel Web intake and Crower aluminum shaft rockers. Not sure how much lighter the production 5.0 hyd roller blocks were than the early 70s 302 blocks, after the roller block broke, I went with a 73 block, I never compared the weights of the roller block to the 73 block.
Title: Re: 347 build for my 64.5 mustang
Post by: Heo on May 15, 2022, 12:53:45 AM
Darts new "302" block

(https://i.postimg.cc/3NQqjKLp/thumbnail-IMG-3315.jpg) (https://postimages.org/)
Title: Re: 347 build for my 64.5 mustang
Post by: machoneman on May 16, 2022, 07:15:53 AM
I weighed both my SBF 331, which used a 1973 production block, and my Dart blocked 347, and the 347 was 35 pounds heavier. Be aware, that these were complete carb to pan engines, and in addition to the differences between the 2 blocks, there were some other pieces that were different between the 2 engines. The 331 had a cast crank, stock timing cover and water pump (aluminum 5.0 Mustang pump), Victor Jr. intake and Comp steel roller rockers, where the 347 has a steel crank, a Jesel timing belt drive and Meziere electric water pump, and a Parker Funnel Web intake and Crower aluminum shaft rockers. Not sure how much lighter the production 5.0 hyd roller blocks were than the early 70s 302 blocks, after the roller block broke, I went with a 73 block, I never compared the weights of the roller block to the 73 block.

I went back to look at the old 'Net 54 site for block weights. Our own Falcon67 stated (way back in 2006!) that a D2 1974 W block weighed 165 lbs. with caps, cam bearings and freeze plugs.
Title: Re: 347 build for my 64.5 mustang
Post by: Rory428 on May 16, 2022, 09:13:08 PM
Pretty sure the extra deck height of a 351W block would make it a fair bit heavier than a 302 block.