I want to build up a custom engine for my 95 Camaro. Its a 3.4L. I don't want a LT-1 stock swap. I was considering a 454 conventional block. I know the LT-1's are reversed cooled. But why? Block design or just flow direction? Could I take a Merlin 400 small block and put all the LT-1 accesories and intake on it? Or are reversed cooled blocks exclusive to LT-1's???

 

As part of the "reverse cooled" design, the LT1/4 block (Gen 2)and heads have unique coolant passages. It is possible to weld up LT1 heads and redrill the coolant holes to allow them to be used on a "conventional" (Gen 1) smallblock. You can also go the other way, and put "conventional" heads on an LT1/4 block, with rework of the coolant passages.

If you were thinking of a 454 based on a Merlin SBC, it wouldn't make any sense to use the LT1/4 heads and intake, they wouldn't support a 454. You would need top quality Gen 1 SBC aftermarket heads to support a 454. So, you buy a Merlin block, some aftermarket Gen 1 SBC heads, then find a fuel injection system to fit on it, and that will fit under the hood.... a problem..... you may need a cowl hood. It will be even more difficult with a tall deck block.

Then you need to address the distributor issue, using a "pancake" style distributor, or adapting a distributorless ignition. Otherwise, fitting the distributor under the cowl of a 4th Gen presents a smalll problem. Cutting the cowl out is another solution.

Then you need to address the issue of the K-member.... I doubt a stock 4th Gen K-member will allow a Merlin block and enlarged oil pan to fit.... time for a BMR or PA tubular setup. About $1,000 with the a-arms.

Then there's headers..... with a taller deck height.... and with the non-siamesed port design on some better flowing aftermarket SBC heads you will need custom 2" headers...... about $2,000.

Hope you have a healthy $$$$$ budget......