I was wondering if anyone has put a tall deck 10.200 big block into a 4th gen F-body. I know a standard deck fits, but I came across a tall deck cheap and want to know if it fits before I buy it. Right now I have a carbed 355 small block and want to step it up.

 

No evidence, but if I were to guess id say no. If you figure an LT1 intake has about 4" between top of intake and cowl, so just a big block with a low rise intake has to be within 4", you figure a tall deck BB, and you arent gonna have no puny dual plane on it.... thats just my .02

 

Yes you can but you have to cut all the way to the cowl. I have 5" hood to so that helps, header wise you have to do some fabbing.

 

Yeah, "fits" is a relative term. To be honest, since you can make a very nice 572" motor from a short deck block (4.500x4.500"), I wouldn't think it worth the extra trouble. But there is nothing wrong with a 672 (4.625x5.000") either!

Rich

 

The tall deck blocks have a .400" higher deck. This is because the truck engines have an extra compression ring on the piston.

Tall deck blocks only really make a better rod/stroke ratio when converted to automotive style pistons. Bore is still bore and stroke is done by the crank. Adding an extra .400 deck height doesn't mean you get to use a .200 longer stroke crank. You use .400 longer con rods and pushrods. You also need a talldeck intake or spacer plates to use a short deck intake on a tall deck block. You also need a tall deck distributor or an aftermarket one with an adjustable slip coller. Because the exhaust ports are higher, custom headers need to be fabricated since any short deck headers that would normally work, will likely not fit under the floor.

There are no factory production 454 tall deck blocks. They're either 366T (6L) or 427T (7L). The 427T block will have the same bore as a 454 and has the most potential. The 366T bore is too small to make it a worth while performance engine. The upside is that the 427T block can easily be bored out 0.125" over. Add a simple 4.250" stroke crank and you get 511 CID with a good rod/stroke ratio.

 

Well, I don't really agree with Stephen's post. Yes, it does describe the history of the tall deck block well. But the way the blacks are cast they will definitely accomodate a longer stroke than the short deck. Take a look at http://www.nescaracing.com/BBCinfo.html and you will some common short and tall deck combos. The chart implies that a 4.375" stroke is the upper limit for a short deck, but there are 4.500" short deck 572's out there. Bowtie or aftermarket tall decks accomodate longer strokes. 4.75" is common and longer strokes are possible with the tall deck but not the short.

Rich

 

To clarify further, the aftermarket blocks are cast for extra clearance, but the stock GM tall decks are not. They have the same configuration as a 427-454 bottom end. Nothing extra. The pan rail may still need some clearancing (depending on rods) if you plan to add a longer stroke. Been there done that.

The GM Bowtie & other performance replacement style blocks are more generous.

True most will go .125 over, but many are better suited at .100 over. They are basically dinosaurs now since you can get a 502 block cheap & get extra cubes without all the boring. I still have a few laying around, but lean towards the aftermarket now for strength & better bore selection. The big bore helps cylinder head flow anyway, so if possible go big.