[pat123]

I can get a 1986 454 for $500 but i would like to have the old look (68-72). Are they the same? If thair not what are the differences?

 

[hotrod69nova]

they look the same on the outside.

 

[taz3]

they look the same on the outside.

X2 the only external difference is the balancer other then that most can't tell.:no:

 

[WILMASBOYL78]

454..

If you drive fast enough...no one can see the engine :yes:

wilma:devil:

 

[The Big Al]

Nothing "ORANGE ENGINE PAINT" can't fix!

Al

 

[pat123]

I dont want to run the computer would i need to?

 

[taz3]

Replace the intake & throttle body with a carb unit, as well as the distributor. The only thing I don't know is if the BB all take distributors, I know the new SB don't use a distributor the have a crank sensor. This should be a problem with an 86 BB though.

 

[rustysrustyduc]

Ha! I'm putting a Gen VI in my 71 right now.

The big hassles are:

1) Oil pan. You basically have to buy a new GM, Milodon, Moroso oil pan. As there are no factory "cars" with this engine only trucks. And their oil pans don't work.

2) Also, the flywheel is different somehow. I happened to have an extra one, but they aren't the same as a MkIV. I'm not sure about the flexplates.

There are some other differences.. if you are getting one from a truck, make sure it has a mechanical fuel pump pad, and a drilled and tapped spot over the oil filter for the clutch pivot if you are going to use a stick trans.

You can use normal intake manifolds, so you can use whatever you want. Same for headers.

There are other internal differences, like the cam and stuff. That's the big advantage. Factory roller cams. Cheap. In fact, heres my ad for my old setup. (sorry for the selfish advertisement, but it drives home the point)

http://sacramento.craigslist.org/pts/1241364941.html

I mean, where else can you get a full roller valvetrain for $165?

That's where a Gen IV shines over a MKIV.

 

[taz3]

Ha! I'm putting a Gen VI in my 71 right now.

The big hassles are:

1) Oil pan. You basically have to buy a new GM, Milodon, Moroso oil pan. As there are no factory "cars" with this engine only trucks. And their oil pans don't work.

I would think a 396 pan would work, wouldn't it, or is it because of the main seals? I've always played with the lV's.

 

[rustysrustyduc]

I would think a 396 pan would work, wouldn't it, or is it because of the main seals? I've always played with the lV's.

Hi Taz,

No that's one of the big diffs between Gen V and MKIV blocks. They are a one piece oil seal. So the pans are different. Even the oil pan gasket is one piece too!

I imagine if you were a super competent welder, you could weld a MKIV bottom to a GEN V upper, you could have something.. but I'm not that good!

 

[pat123]

I think if i get this nova i will put either a 396,427, or 454. I would like to keep it around the same year but i guess if theirs no difference it should be fine. Is it hard to find one of these around a 69? If so how much can they fetch?

Thanks

 

[taz3]

Hi Taz,

No that's one of the big diffs between Gen V and MKIV blocks. They are a one piece oil seal. So the pans are different. Even the oil pan gasket is one piece too!

I imagine if you were a super competent welder, you could weld a MKIV bottom to a GEN V upper, you could have something.. but I'm not that good!

Yep, I remember going through this when wanted to build a new style 427.

 

[taz3]

I think if i get this nova i will put either a 396,427, or 454. I would like to keep it around the same year but i guess if theirs no difference it should be fine. Is it hard to find one of these around a 69? If so how much can they fetch?

Thanks

I have 3 of them!

The older style BB's, running fetch $2000 & up, up here, L78's start around $5000 for a long block.

 

[pat123]

Is that rebiult or in need of a biuld?

 

[71SS454]

If the newer engine dosen't have the hole for the clutch pivot ball and you want to run a stick, Scroggin Dickey sells an adapter peice that bolts onto the bellhousing mounting bolts, so there is no problem there. Just get the new oil pan and you're ready to go.

 

[pat123]

Doesnt that year have a carb? I also heard the compression ratio was lower, so are the heads a lower cc head or are the pistons dished?

 

[taz3]

Is that rebiult or in need of a biuld?

That's rebuilt or running condition.

I think 86 might be FI not sure though, the heads have small ports. If you want to wake one up, change the heads to an older head, so they can breathe better.

 

[pat123]

Would i be better of searching for an older style BBC?

 

[taz3]

Would i be better of searching for an older style BBC?

I don't think it really matters, it's more of a personal preference, I prefer the older stuff, it will also always have more demand if you want to sell it. You may find the older BB's, are harder to find out your way though, because you can drive you cars more and they break, out here we have more engines and less bodies because of the short summers.

 

[pat123]

Is their a difference between car BBC and trucks?