Big Block Questions

[crucial118]

What's up fam? I am thinking of going bbc. I have seen several bbc's on CL and most, that have been seen, have been truck blocks. I have been reading that the truck blocks are a little wider and taller. Will this pose an issue for swapping into our cars? Is one more preferred(truck or passenger) and why? Head choice also. Which is a better choice? I have read that the ovals are better. Also, reasonable price header choice. Any other info would be appreciated. Thanks.

 

[454cutlass]

There are tall deck and normal BBC. Just different part fitment. For heads stay away from peanut port heads. 049 and 781 heads are probably the best stock oval heads.

 

[crucial118]

So both tall deck and passenger deck will fit in a gbody?

 

[-83MONTESS-]

Tall decks are harder to find and werent from all trucks. I got my 454 out of a 78 dump truck and its a standard 9.8" deck block. The oval port 049 and 781's are the best factory casting head you can find and both react well with a 2.19-1.88 valve upgrade. You can use small block engine mounts for a gbody. Headers for a gbody big block swap are over $400 for painted ones. I have heard of people using 68-72 Abody Chevelle headers and 67-69 Fbody headers which are alot cheaper. I am going this route on my 496.

 

[tk76]

Just make sure it's not a tall deck. Mounts right up to sbc engine mounts. Even the distributor and possibly starter are the same.

 

[crucial118]

Thanks for the input. Not sure what I want to do yet. Just weighing options. Caught between the cheaper route(400 small block and everything off my 350 bolts to it) or 454 and all new parts.

 

[565bbchevy]

If you decide to go the BBC route stick with a standard 9.80" block the extra .400 for a tall deck will cause fitment issues with engine swap headers and you will need a tall deck intake manifold.
On standard deck BBC the only parts that interchange with SBC are the starter and distributor( tall deck also with the right intake)
As stated the best stock oval ports are 049 and 781 castings and with larger valves and pocket porting they flow pretty well for a stock head.
SBC engine mounts work and stay in the same location.
Regardless of AC or non AC there will be interferance with the case if you use anything other than a stock (very short) valve cover and if you plan on a performance build with a stud girdle you will have to make room and depending on the size of your brake booster there could be an issue removing driver's side valve cover.
Also the big block is longer and the length is added to the front of the engine which limts your clearance depending on your fan choice set up.
If it is anyway affordable I would go with an aluminum heads the weight of an all iron big block even with upgraded front springs will be noticable when driving and cornering and if not maybe try to lighten it with a glass hood and loss the AC if so equipped.
I will tell you few things are more impressive when you go to a car show and open your hood and there is a Big Block Chevy in there.

 

[454cutlass]

400 are a nice engine. Do you just have the block or is it complete. They have different cranks and require steam holes drilled in the heads also needs a 400 specific oil pan. Not to sure if you have to use a small base Cam with a 400.

As stated above nothing beats the look of a bbc

 

[crucial118]

400 are a nice engine. Do you just have the block or is it complete. They have different cranks and require steam holes drilled in the heads also needs a 400 specific oil pan. Not to sure if you have to use a small base Cam with a 400.

As stated above nothing beats the look of a bbc

I just bought the short block today. I will post pics later in a slow build thread. Yeah, I read about the steam holes and oil pan. Will send the heads to get holes drilled when the block checks out ok from the machine shop. If all is ok with the block I'll get a driver's side dipstick oil pan. But, what is a small base cam? Haven't read about that yet.

And yes the look of a bbc is a beast, but I can compete with my HSR setup

 

[565bbchevy]

If you are staying with the stock bottom end (same stroke and rod length) then a small base circle cam is not required it is usually only needed in a 383 with 6" rods then the clearance gets tight around the cam depending on which rods are used.
Assuming you will be buying an aftermarket extra capacity oil pan pretty much anything out there clears your stock 3.75 stroke.