Well guys, i need some assistance :) BBC info,PICS ADDED

[4xcrazy]

I recently picked up two BBC blocks for a pretty decent price, especially since the guy threw in a Weiand single plane manifold, and a crank.

Here's the deal, i have always owned and worked on SBC 262/305/350,,,

these BBC things are new to me and would like some assistance in building one for the dually.

I ran the numbers on Mortec.com, and was alittle dissapointed at what i found out.

1st block has numbers of 3999290, the second block is numbered with 3999289.

the 3999289 block has a cracked cylinder, (was free with the deal and was told about it)

the 3999290 i was told was a 454, and according to the list on Mortec, it says it's either a 402 or a 396.

Main question,,,,396/402,,,is this the numbering from certain cranks that are installed in this block? can it be setup/built as a 454 engine?

I wanted this engine to be a reliable "towrig" engine, not too worried about fuel mileage, as that's part of the trade off of towing heavy things. Since it needs a complete conditioning and rebuild, i am looking for certain things (not race spec'd) but more for items to get some decent power and reliability out of this engine once built.

any info on this would be greatly appreciated. thanks

 

[4xcrazy]

Well, just starting the searching for information on these things, and went outside to measure the bore sizes, they are definately a 402 and a 454, what sucks is the one with the cracked cylinder wall is the 454, and looks to have already been bored out about .020.

Kinda bumming me out here, as yet again, i was burned on a deal from somebody here in Phoenix. the guy had the 402 advertised as a 454, and ensured me it was good. I guess i am also partly yo blame, for not asking for the numbers over the phone and running them prior to purchasing....

OH well, will see what i can do

 

[4X4HIGH]

You can always have the cracked 454 blocked sleeved then bore it to the next oversize. The 402 cannot be bored to make it a 454.

 

[dangerzone]

The 402/396 cannot be made into a 454. The 427/454 have a 4.25 bore and the 396/402 have ~4.00 bore. You can probably have that 454 sleeve though. I have sleeved a few motors and its not to bad so it shouldn't cost an arm and a leg.

 

[4xcrazy]

You can always have the cracked 454 blocked sleeved then bore it to the next oversize. The 402 cannot be bored to make it a 454.

yeah, i forgot to put that in the last post, i realize it can't be punched out to 454 size, kinda sucks...

Any ideas as to what it costs to have a block resleaved? i keep getting different numbers from people, and they are WAAAY different from each other....Haven't called around to machine shops yet, but that type of stuff is soon to come.

 

[4X4HIGH]

At my shop i charge $125.00 to sleeve a cylinder.

 

[4xcrazy]

Cool, i guess that's not too bad then, going to call around next week and see what they do it for here, may just go ahead and have this done, drop it off, have all the work done to it that it needs.

Basically it needs a complete cleaning, measurements and whatever else goes into "prepping" a block for assembly. They were sitting outside for awhile, and have a pretty good amount of surface rust.

Any ideas as to the differences in HP/TQ between the two motors?

 

[Russell]

402 probally blows the 454 outta the water in horsepower and torque...

Those were very powerful engines, and worth a whole lot more than a 454 to the right guy

 

[4X4HIGH]

402 probally blows the 454 outta the water in horsepower and torque...

Those were very powerful engines, and worth a whole lot more than a 454 to the right guy

How totally wrong that statement is. The 454 will put down more torque and HP than ANY 402 any day of the week.

 

[b454rat]

I had a 468 that had a sleeve in it. When the motor took a cump, and noticed the crack, I thought the motor was hosed. But machine shop said it was no biggy, and that he had a motor with 8 sleeves in it. I remember reading somewhere that CERTAIN 396/402 blocks could be bored to 454 size (can't remember what the bore size is) Maybe it was putting the 454 crank in the 396/402, some needed clearancing some didn't. Could always get a 502 block from GM.....

 

[79k20350]

Theres nothing wrong with a 402. I definetly would not overlook it for a build, especialyl if its a good block. They can put out more than respectable numbers

 

[4X4HIGH]

A 396 has a 4.094" bore, 402 = 4.124" bore, 454 = 4.250" bore. There is no way a 396/402 block will accept an .125" overbore. Also a 454 crank will physically fit in a 396/402/427 block but the block will need to be clearanced if you want that crank to actually rotate within the block.

 

[Russell]

How totally wrong that statement is. The 454 will put down more torque and HP than ANY 402 any day of the week.

Well yeah, if you build em up!

Stock engine compared to stock engine, a 402 from the late 60s will kick the living crap outta a mid 80s smogger 454!

 

[nvrenuf]

Well yeah, if you build em up!

Stock engine compared to stock engine, a 402 from the late 60s will kick the living crap outta a mid 80s smogger 454!

You're comparing apples to oranges... Try comparing the same era engines with similar performance packages and the 454 is hotter.

 

[4xcrazy]

Let's try to keep this civilized please, i do appreciated the debate of power differences on the two motors, as this is what i was looking for, and what my options would/could be with these engines.

As mentioned in previous post, this will be installed in a truck that is going to be used as a daily driver, and will be asked to do some decent towing at times.
When i say decent towing, i am referring to something of the size of a 25-30 some odd ft travel trailer, and possibly a trailer behind that for towing the trail rig,,,yes, again, i know it will be a struggle at times, this is why i am asking what i could do with either of these motors to add some decent power to assist in this towing task, and which motor would be the better builder.

I personally would have assumed that the 454 would be the better HP/TQ motor, but again, i honestly know nothing of the BBC engines, and how they can be built for power increases without going overboard and into the full on racing type setups.

Looking to keep the build to around $250 or so,,,


















































yeah right

 

[rjfguitar]

If they can sleeve your 454 without costing a bunch, and can do it reliably than I would build a 454. If the block is junk, then I wouldn't look away from the 402 block. If 4x4high says a 454 crank will fit with some clearancing, that wouldn't be a bad option. You'd have a stroker 402 that would be 420-430ci's?? and would still be mighty strong with a nice torquey cam and head setup.

 

[Russell]

yep, its true that if you build both engines similarly, the 454 will have more power and torque, just cause it has more cubes, but if you are comparing a bone stock engine with another bone stock engine, the 402 will win hands down. Heck, a late 60s 307 could take the mid 80's 454 on a good run for it's money... Most of those engines were over 300 horse, and the 454s were like 200 - 210ish...

 

[4X4HIGH]

yep, its true that if you build both engines similarly, the 454 will have more power and torque, just cause it has more cubes, but if you are comparing a bone stock engine with another bone stock engine, the 402 will win hands down. Heck, a late 60s 307 could take the mid 80's 454 on a good run for it's money... Most of those engines were over 300 horse, and the 454s were like 200 - 210ish...

You are losing sight on what is being said. You can't compare apples to oranges. Pick any year 402 and compare it to the same year 454 and the 454 will win hands down. The reason engine numbers started to dip in the mid 70's into the 80's was due to the smog requirements.

 

[rjfguitar]

yep, its true that if you build both engines similarly, the 454 will have more power and torque, just cause it has more cubes, but if you are comparing a bone stock engine with another bone stock engine, the 402 will win hands down. Heck, a late 60s 307 could take the mid 80's 454 on a good run for it's money... Most of those engines were over 300 horse, and the 454s were like 200 - 210ish...

I tend to disagree with this. A 60's 307 may outrun an 80's 454 in a Camaro, but not in a big heavy truck. My K30 crew cab service truck weighs almost 8K and it scoots pretty good for the stock 210HP 454. From my experience with small blocks, a HP happy 307 still wouldn't be able to move my big heavy rig around like my 210HP 454 does.

 

[Russell]

Thats very true, the 454s did make a lot of torque, regardless of how low horsepower numbers were. I suppose its tough to compare apples to bananas