302 BOSS BLOCK VS MAN O WAR

[mikethebike]

Because my machine shop has had a rash of them since they came out. And they said it starts to get a little thin for street driving at .060. Not that it can't go farther. You can do a 347 also, but the pistons are deadly close to being out of the bottom. That shop won't even assemble a 342 in the new blocks because the skirts are so short.They have another over there right now. i'll see if I can steal some bore thickness measurements from them

Why not intall a silicon impregnated nickel sleeve?

 

[mikethebike]

I have a original 302 Boss block in the basement but I dont want to use that block. I didnt know that Dart also made a 302 block so I done some research and found out that Ford crate motors call there Block a sportsman and is used on three of there lower HP engines but on ther High HP 347 engine they use the new Boss Block, SO is what Ford calls the sportsman Block one of Fords blocks or a Dart Block,,, HMMmmmm,

Is your block an early 69 or a late 69/70? If it has been sleeved it should be the 69 motor. They warrentied so many of them Ford finally started using th real T/A blocks.....then they broke pistons.

 

[TOM B]

Is your block an early 69 or a late 69/70? If it has been sleeved it should be the 69 motor. They warrentied so many of them Ford finally started using th real T/A blocks.....then they broke pistons.

I DONT UNDERSTAND YOUR COMMENT. If my block was sleeved its a 69 block?
What does having the block sleeved have to do with the year.
No my original block has no sleeves put in.
If Ford is building there 347 Hi horse power crate engine with there new Boss 302 block then I must say that the sleeves are NOT to short and that 1 thick headed machine shop owner is not Judge and Jury.

 

[wicked93gs]

well, he did say the skirts were visibly thinner...so its not solely the machine shop owner's opinion here, but I would google it to research it further if I were you

 

[Dark Knight]

One thing that bothers me with the world and dart blocks is the lack of screw in freeze plugs. For that much $$$ you would think they would do it. Thats one good thing about the new boss block, the freeze plugs are screw in as well as the oil galley plugs. O-ringed too.

Why would you add N20 and a blower instead of upping the boost. Yes, a vac. pump will help alot. And I sure hope you're running a forged crank and some really god pistons.

 

[mikethebike]

I DONT UNDERSTAND YOUR COMMENT. If my block was sleeved its a 69 block?
What does having the block sleeved have to do with the year.
No my original block has no sleeves put in.
If Ford is building there 347 Hi horse power crate engine with there new Boss 302 block then I must say that the sleeves are NOT to short and that 1 thick headed machine shop owner is not Judge and Jury.

I said that it PROBABLY was a 69 and here is why:

I owned a 1970 BOSS-302 when it was a current production car. I bought a used1969 motor to get the double-cross-drilled crank and it was sleeved in the #7 hole. Jack Roush, Jake King and Dan Perrin all said (and this was supported by a FoMoCo service rep) that the early stock motor was replaced with the Tran-Am blocks around mid-year 69 because they had replaced all but 50 or 60 under warrenty due to cracked cylinder walls. After this when you would disconnect the rev-limiter and let the engine rev to where it made the power the heads were capable of supporting you would break the piston about 1 to 1.25" up from the bottom of the tang (This point is right where the bottom of the cylinder wall aligns with the piston at BDC) on the non-thrust side.

As far as the new blocks are concerned, I wouldn't have a clue as to how good or bad they may be seeing as I have not and most likely will never own one.

And where pray tell did you get the idea some "thick headed machine shop woner" said anything?

 

[mikethebike]

At this point, why even go the BOSS block route? Why not just go with the known quantity you are getting with a Dart Sportsman block?

You post here and don't believe Ford is the God of autombiledom and can do not wrong? Now that is a change of pace.

BTW...I agree 100% with you.

 

[mikethebike]

One thing that bothers me with the world and dart blocks is the lack of screw in freeze plugs. For that much $$$ you would think they would do it. Thats one good thing about the new boss block, the freeze plugs are screw in as well as the oil galley plugs. O-ringed too.

Why would you add N20 and a blower instead of upping the boost. Yes, a vac. pump will help alot. And I sure hope you're running a forged crank and some really god pistons.

Good point, but you could thread them yourself.

 

[10secgoal]

I DONT UNDERSTAND YOUR COMMENT.
If Ford is building there 347 Hi horse power crate engine with there new Boss 302 block then I must say that the sleeves are NOT to short and that 1 thick headed machine shop owner is not Judge and Jury.

Found this on another forum.

I would not recomend going to a 3.400 stroke crank I would stay with somthing like 3.250, due to the shallow bore of the boss block. We tried that and noticed that our piston skirts (arias) came out of the bore almost to the oil ring. Maybe someone who has more experience with these blocks could chime in here. A plus though is the revised cooling/water jacket design, apparently is great on the street.

And this if you can look at it. Third post down http://www.theturboforums.com/smf/index.php?topic=100489.0;topicseen

So now I've said it, and this guys said. So I don't think the machine shop is thick headed, seeing as they do it for a living, and you've only read what ford tells you. FWIW, the thick headed guy has owned and worked on top fuel dragsters and raced head to head against the likes of Force and Pedragon.
You asked about the Boss block and got truthful answers. If you still wanna buy one be my guest.

 

[Hack]

Dynacorn built a new Boss 347 and it's in their fastback show car.

There is just no way...

I get the feeling someone has an axe to grind against Ford. If anyone reading this thread is considering the Boss block, don't let these people discourage you from at least contacting Ford to be certain everything is fine.

 

[blown65]

The motor that we just are about done with is a Dart 302 4.165 bored setup. (370 cuin I think) One thing about the block, they said it was the dirties filled block they had ever got. Lots and Lots of cleaning to get it clean. I don't remember that being such an issue with my Ford R302 block.

 

[10secgoal]

Dynacorn built a new Boss 347 and it's in their fastback show car.

There is just no way...

I get the feeling someone has an axe to grind against Ford. If anyone reading this thread is considering the Boss block, don't let these people discourage you from at least contacting Ford to be certain everything is fine.

Yeah, dynacorn didn't build the motor. And neither did the actual comapny that built the car (not dynacorn). Alot of shops don't care, just get the motor out. And reliability won't be and issue with a car that will never see more than 200 miles, ever. The last car they built finally fired,and only two years after being built. I guess because one company did it, it must be OK. At least get some facts or see the thing for yourself before saying there is just no way.
As for an axe to grind...? It's a conspiracy. I went over to the other board and asked him to post that for me so I could come back here. ( I run an aftermarket block, made by Ford, no grinding here.)

 

[TOM B]

Well, ok, alot of views about the boss block, Thanks to you all. I built my 347 and my skirts did NOT come out that far as said in 10 second post, There are a few different ways to make a 347 stroke, different piston pin hight, different rod lenths,,, maybe they used a setup that pulled the piston down farther. I have forged PROBE pistons.
I will call Ford on this issue and I will call again to get a different reps opinion on the skirts. Thanks again.

 

[10secgoal]

Got any pics ?
Or what you used that was so different ?

 

[10secgoal]

http://www.theturboforums.com/smf/index.php?topic=100489.0;topicseen

Same thread, 15th post down now, different guy, same problem.

For one the cylinders on the Boss seem to be about ¾ inch shorter than the Dart.

Pease show some pics. I'm just curious how yours is so different than everyone else's block. Pin hieght and all that other junk doesn't matter. The stroke remains the same. Which is 3.4, and will still cause the piston to come down the far, reguardless of the rod length. Even if, you can't make up that kinda difference.

 

[67topless]

Just to make sure I understand

I've read the entire thread and just want to make sure I understand: Most are saying the 302 Boss Crate engine is a bad design (stroked to a 347)? It's out of my budget, but I have been looking at it the last couple of days as I am in the market for a crate engine my self. Not trying to stoke the fire any more than it appears to be all ready. Just wanted to make sure I am reading correctly.

Thanks,

Scott

 

[C0V3R]

67 you are reading correctly.

Its probably fine for a 302.

 

[Hack]

I've read the entire thread and just want to make sure I understand: Most are saying the 302 Boss Crate engine is a bad design (stroked to a 347)? It's out of my budget, but I have been looking at it the last couple of days as I am in the market for a crate engine my self. Not trying to stoke the fire any more than it appears to be all ready. Just wanted to make sure I am reading correctly.

Thanks,

Scott

The Boss 302 block is designed specifically to be stroked to 347. You can also bore to 4.125 to unshroud the valves and get more than 347 cubes if you want.

Yes the bores are shorter than regular 302 blocks. The reason the bores are shorter is so that you can build a 347 stroker without having to notch the bottom of the bores for clearance for the rotating assembly. That is why I stated above that the block is designed specifically for the 347 stroker. Ford shortened the bores on purpose to make the 347 stroker rotating assembly drop right in without any modifications to the block.

 

[shelbe67]

ford mite be building a "big bore stroker" and not using a longer stroke crank on their 347 stroker crate engine. I did read though that the bottom of the cylinders are shorter but I think it was for clearance for the crank but I am not sure. the skirts of the piston would hang lower I am guessing this mite cause some instability of the piston but I would assume that it wouldnt make that much of a difference but could be wrong

 

[TOM B]

It looks like 10secgoal was right after all the bores are shorter, but just because Ford disigned it that way so you dont have to notch it, I would have left the bores longer for more piston skirt support, even with a notch in the bore it would have added more support.
But, the question is still out there. I am running a paxton supercharger with around 15 psi and NOS. Ported 202 Edelbrock rpm heads Nos is set at ony 150 horse shot but can go up to 400. Victor jr intake with a holley commander 950 fuel injection, set up to flow up to 960 CFM
I have a Mexican 302 which is stronger than a regular 302 with stronger caps and it has a main stud girdle and ARP bolts through out. never had it on a dino. dont know the horse power
WILL IT HOLD UP!