I've wanted to do this, but don't have enough cells for that yet. Yes would need high current LiFePo4 cells, and some form of busbar internal wiring.
When selecting cells the CCA rating of the original becomes the 10s rating of the new lithium Ion cells.
For example, to replace 400CCA car battery, you could use A123 26650 cells* that do 50A normally and 120A for 10 seconds. 4 in series to get 440CCA, 4 in parallel to get 12V, 16 cells total. Downside is you only have 10Ah, so perhaps add more parallel cells till it's the same size as the original battery.
I've seen dedicated LiFePO4 replacements for lead acid batteries, that have inbuilt electronics. Those were done as ~8Ah SLA replacements, I'm sure somewhere is a proper car battery version.
* these cells are floating around ebay.com in packs of 90 or 100.