RAPIDFIRE

My nephew and I are just starting a 454 84 Camaro build.me and another guy just towed the car to my house a couple days ago.I have seen several 454's for sale but one thing I am unsure of is are there some motors to stay away from ???one guy has one that is seized up, kinda makes me a little nervous.another guy has one out of a (96-up cast number 10141279) school bus.
the intended use is the build it to 496,and make it streetable. nothing to wild but nothing to mild either.Jason (my nephew) wants a nice car to be able to take to car show and I am sure he would like to show of its power a bit lol.this motor would be carbed and 100% natural aspirated,no power adders.just something very fun and reliable.Jason is over in Iraq right now so I am kind of his gopher.


so what castings should I steer clear of?? thanks in advance for any input you guys may have.

AlkyIROC

Depends on what you consider junk. Personally, I think all the GenV engines are junk. They were only used from 91 to around 96 before GM switched to the Mark VI engines.

There are no real junk Mark IV engines but there's about 100 different head castings to go with them and those can make or break a rebuild.

The Mark VI engines are a completely new design and don't share many, if any, parts with the older Mark IV engines which is what the majority of aftermarket parts are made for.

Air_Adam

Be careful with engines from busses and trucks larger than 1-ton... lots of those are 366T and 427T engines, which are tall deck BBC engines. A 396/427/454 is a short deck BBC, which is what you want.

The best core you could likely find would be a '70-75 454, because they came with the 049 or 781 casting cylinder heads. Those are the large oval port heads, which are probably the best all around 'hot street engine' head of all the production BBC heads. The later engines up to '89 or so had basically the same shortblock as the '70-75 engines, but had the lesser cylinder heads, commonly refered to as 'peanut port heads'. They had small 200cc intake ports (large oval 049 or 781 heads were in the 270cc range).

AlkyIROC

Only the Mark IV engines had tall decks and only the 366 and 427. There were no 454 tall deck production engines. By the time the Gen V engine was introduced, GM stopped producing tall decks for the larger trucks and the engines were only available as a 454.

ericjon262

If I was going to do the swap, I would look for an L18 or an L21/L29, they are vortec headed 496's or 454's, swap a cam and intake, and I'd bet you could be at 500 hp no prob!

http://en.wikipedia.org/wiki/Vortec#7400

just a thought-

Eric

jstoltz

iTrader: (16)

the 496's don't use a distributor I believe. (correct me if I am wrong) so you would need a cam driven distributor setup which is kind of pricey. I am looking for a 1996-2000 vortec 454 which supposedly they have really good heads on them and just going carb'd on mine also. the L21 is the one I am looking for because of the forged internals. Quick pocket port on the heads and headers and maybe small cam change along with the quick fuel 750 dbl pumper I got and I am done with the engine. (or am I? First thing bigger carb)

ericjon262

I imagine that even if the 496 didn't use a distributor, when you swap intake you would have the ability to run one, remeber, the oil pump is drivin by the cam, so the stock cam(which I would swap out) should have a gear for the distributor, and a new intake will have the hole for it to slide into.

RAPIDFIRE

hi
I can use ?
Potential problems ?

head -336781

block -10237297...454.......96-up...4-bolt, Vortec 7400", "L-29" Gen.VI

thank you

five7kid

iTrader: (14)

It's fine. 1-piece rear main seal.