Blueprint 302 (365 HP) vs 347 (415 HP) vs 408 (450 HP)

[Broncobowsher]

I would say at a very minimum start with an '84 block, that will get you a 1-piece rear main seal.
My choice would be the '94-97 blocks because they accept stock style roller cams

In the old days I would look for the early blocks because of shorter deck height (more power), allegedly beefier castings. But now I am older and wiser I will take a newer block that had more accurate cores placed inside during casting, one piece rear main that are generally leak free, and easy roller cams since todays oils don't work that great with flat tappets. The later EFI engine also tend to have minimal cylinder wall wear and a better chance of not already being rebuilt and bored too much. If you are looking at a stroker kit, the taller deck to keep compression ratios in a happy place are better.

 

[duffymahoney]

I would caution that with a reality that most people dont post when they have great experiences. I have had really good luck with them, their service and response was stellar and even went beoynd warranty to reslove issues for me. I am sure there are exceptions but internet complaints far outweigh the masses of happy customers that you never hear from.

Between here and facebook, it's a fair bit of people. I was just warning.

 

[73azbronco]

yes.

Any 351 good as next, other than make sure you have it magnometered to check for cracks and bore checked for size. By the time you finish that, I say a new Dart block for $2,500 is cheap insurance.

 

[hsach]

yes.

Any 351 good as next, other than make sure you have it magnometered to check for cracks and bore checked for size. By the time you finish that, I say a new Dart block for $2,500 is cheap insurance.

Besides money, is there any reason NOT to get a Dart block if you are building an engine from scratch? I am still planning on a 351W, and saw a post a while ago that possibly had to modify the Dart block for stock engine mounts. I can't find it now, but I didn't know if there were any "gotchas" if you went with a new block from Dart or another manufacturer. I haven't been looking hard, but there aren't many 351 blocks in my area as all of the junk yards dumped their older vehicles in the last few years. I can't find anything earlier than late 90's.

 

[73azbronco]

my stock 96 5.0 had to have the supposedly stock engine mounts ground down on the edges to fit. The extreme mounts needed way to much grinding for my liking. I would expect to grind a dart block mounts.

Some machine shops may sell you one of their "finds" a pretty good way to get a 351 core, but other than that, I know of no reason to avoid a dart. I'd get a 9.5 deck (stock) anyway to avoid intake issues.

 

[1969]

I appreciate threads like this. I aspire to put a 408w in my Bronco one day.

 

[73azbronco]

Aspire? I'm down right threatening a 427. Nvrstuk? Any reason to not go 427 with a dart block vs 408?

 

[1969]

Aspire? I'm down right threatening a 427. Nvrstuk? Any reason to not go 427 with a dart block vs 408?

Yeah one day I’ll do it. I have other priorities right now with it so it’s actually drivable. So I appreciate threads like this.

 

[nvrstuk]

Careful when looking at 351W blocks which are roller blocks from '94-6. They have been known to crack at the back of the block between the valley and the #2 cam bearing. ANY used block needs to have this area scrutinized for a crack after that cam brg is removed. Usually hard to get someone to agree to this b4 a sale but you need to have this done.

Otherwise purchase an earlier block, make sure you use a retro roller cam kit as the roller cam profiles can be much more aggressive in the lower rpm ranges and this is what brings torque curves and hp curves down in the rpm range.

Good luck finding a good 351W block that only needs .030" and I wouldn't recommend going .060" for a stroker. They are out there but it might take a while.

'69-71 are the "best" years but the deck ht is different than the later years. '71-73 are supposed to have similar block weights and higher nickel content but you can find stuff all over the web to support either claim.

I can type all this out but you might ask your builder what he is willing to work with, what brands of components he wants to use, etc so you can dial in things like deck ht, compr ratio, quench, head cc chamber all before you purchase a block or buy the components and then are stuck with too high or low a compression due to a block with a taller deck, quench #'s that aren't working for ya, etc. This is the part I enjoy but there are at least a dozen important varables as to which direction the build will take.

Can you find a new blank 351W block? That could be a good inexpensive way to go.

 

[nvrstuk]

Aspire? I'm down right threatening a 427. Nvrstuk? Any reason to not go 427 with a dart block vs 408?

None what-so-ever. The # 427 has such a good "ring" to it. What little differences there are isn't worth any worry.

 

[Wrightracing]

I am on the same boat with deciding on a 408w or 427w. I have a bone stock 1989 351w out of a Bronco. If I do a 408, I can have the Block I already have clearanced for the 408 stroker.

The 427 would be nice, but that would require an aftermarket block. I would get a Dart or Ford Motorsports R race block. I missed out on a deal for a Dart block, Eagle 427w stroker kit and AFR 205CC Renegade heads. It was all brand new, but a basket case and I have never put one together from the block up. With spending that much I don't trust my skills on that. I also plan to run a Holley Terminator X MPFI system with Edlebrock Super Victor MPFI intake and Edlebrock 1000cfm throttle body. I already have most of the Holley stuff, I just need some fuel injectors and a ignition box. I probably will do a MSD Digital Off-Road 6 ignition box.

I am shooting for 550hp and close to the same in torque around 3000 rpm, but not sure on that. I want to keep it able to run Pump gas, so the compression will need to stay around 10 to 1.

I definitely want to get it Dyno tuned by a professional. I don't want to be messing with it all the time, want it done right the first time.

I do want to keep the horse power under 600hp to save the drive train and axles from breaking.

David

 

[nvrstuk]

Gotta ask why you can't put the 427 crank in a stock block?? It fits fine.

Sounds like you missed a good combo... you can always have someone assembly all the parts for you if you want if you come across another deal like that.

Can I toss out a couple things? SeimansDeka injectors and if you go MSD, by two of them- or go EDIS.

I'm swapping over to TermX in the near future too. I think I've got a handle on the altitude tune issues.

 

[Wrightracing]

As for the injectors, my plan is Bosch. From what I have been seeing on most of the Holley Terminator X online forums, the Bosch injectors are fairly reliable and they have a good history of quality control.

We put the new MSD Off-Road digital 6 box in a friend's F150 with a 408w and it worked really well. No issues in the last year and a half. I have heard of some quality control issues, but we will see.

What is EDIS? I'm not familiar with it.

As for the 427 in a stock block, yes you can put the crank in, but you run into clearance issues with piston skirts and thin cylinder walls. It is not a recommended combo for a long life of the motor. If I am spending $8k on parts and use a sub par stock block, it is not a wise move.

In Baja, the motor needs to be reliable when you are stuck 500 miles from the closest auto parts store. Not fun being pulled on a strap for a couple hundred miles. It was bad enough being pulled 80 miles in Baja, back to the border when I blew the transmission. Thank God for the CEO of KC High Lites giving me a pull in the middle of the night during the Baja 1000.

As for the deal I missed out on, because I am inexperienced at building motors, I did not want to end up spending that much money on something unknown, sold as is and not have a warranty.

I've done that on a transmission and lost a $1k in the end.

David

 

[duffymahoney]

As for the injectors, my plan is Bosch. From what I have been seeing on most of the Holley Terminator X online forums, the Bosch injectors are fairly reliable and they have a good history of quality control.

We put the new MSD Off-Road digital 6 box in a friend's F150 with a 408w and it worked really well. No issues in the last year and a half. I have heard of some quality control issues, but we will see.

What is EDIS? I'm not familiar with it.

As for the 427 in a stock block, yes you can put the crank in, but you run into clearance issues with piston skirts and thin cylinder walls. It is not a recommended combo for a long life of the motor. If I am spending $8k on parts and use a sub par stock block, it is not a wise move.

In Baja, the motor needs to be reliable when you are stuck 500 miles from the closest auto parts store. Not fun being pulled on a strap for a couple hundred miles. It was bad enough being pulled 80 miles in Baja, back to the border when I blew the transmission. Thank God for the CEO of KC High Lites giving me a pull in the middle of the night during the Baja 1000.

As for the deal I missed out on, because I am inexperienced at building motors, I did not want to end up spending that much money on something unknown, sold as is and not have a warranty.

I've done that on a transmission and lost a $1k in the end.

David

Be extremely careful with injectors, the chinese fake bosch are very hard to tell apart from OEM.

The Ford EDIS or Electronic Distributorless Ignition System is a computer-controlled ignition system developed by Ford that uses an ignition coil for each pair of cylinders (wasted spark). All the coils are placed in a single module called a coilpack.

 

[73azbronco]

Ford EDIS, stock on explorer 5.0 late 90's

 

[rguest3]

94-97 351W Roller Cam Block - F4TE is the engine code if I remember correctly.
Balanced Rotating Assembly, +.030 if needed, 1-Piece Rear Main Seal
H-Tech Pistons, Moly Rings - 9.5 to 1 or so.
AFR 185CC Heads - Roller Rockers and Hardened Push Rods.
Comp Cam XE264HR Cam, (or similar) lifters and Timing set
Edelbrock Performer Intake
Sniper EFI with Hyperspark Ignition.
Explorer Front Dress.

I have done 3 Bronco motors like this build or very similar. One with a smaller Comp Cam (XE258HR-12) and 165 Heads and it ran Very strong. Lots of torque and just a little lope at idle. Less expensive than a 347 and the same cubes.

 

[nvrstuk]

Trying to word this properly...

Not sure why a .030" over bore on a slightly used block with 4.170" stroke is overboring to acheive a 427cu sbf stroker. Very little grinding for the oil pump, and block clearancing needs to be done. I have done a few of these and when purchasing the correct parts it's not an issue.

So there's no thin cylinder walls and therefore no dependability issues. If you can buy a new block then work with a 4.00" bore, but otherwise the extra stroke is a benefit. 408 is great, bit more square if you're looking for 200K miles.

I understand being isolated. Where we used to fish up in the Yukon and Northern BC for 4 weeks-3 months a trip, we would also be 300+ miles from any town with anything more than a gas station or a Hudsons Bay Post (not exaggerating). Dependability is/was the key and is to this day. Driving me nuts when I had some rear end dependability issues for a few years building a "forever" rear end and it was driving me nuts but I think that's solved now. Otherwise I'd drive it anywhere.

Like previously mentioned, EDIS is OE Ford. Super dependable, good to 8K plus. Just trying to help ya. Seems like every year I yank out a few more buddy's with MySparkDisappeared ignition systems.

Wish ya the best...

 

[lars]

(snipped)

Like previously mentioned, EDIS is OE Ford. Super dependable, good to 8K plus. Just trying to help ya. Seems like every year I yank out a few more buddy's with MySparkDisappeared ignition systems.

Wish ya the best...

Or My Spark Never Appeared In The First Place. Lol...

 

[nvrstuk]

Decades of being here on CB, working on local rigs, and now with social media blasting us from all angles I've never read a post on EDIS failing, unlike the multiple failures of MSD. Once again, just trying to help ya with dependability and off the shelf parts.

 

[lars]

Decades of being here on CB, working on local rigs, and now with social media blasting us from all angles I've never read a post on EDIS failing, unlike the multiple failures of MSD. Once again, just trying to help ya with dependability and off the shelf parts.

I know of a couple of guys who adapted the ignition part of it to run 4 cylinder Lycomings on their airplanes, using Ford EEC-IV EDIS modules. Precisely because of the legendary reliability. Kinda don't want the spark to stop when yer wheels are several thousand feet above the dirt...