Cadillac CTS-V - cam install

What's the is the groups opinion of doing a cam swap but still retainer cast manifolds, is it a waste of time or would if be alright. It would be catless with magnaflow xpipe and exhaust

It can be done, but you do end up with less power for the money. I did this on an LS6 with a custom cam from PatrickG, which is designed to work with stock exahust manifolds. I use Randotn Tech cats and had my stock exhaust manifolds Extrude Honed. I later added Trick Flow Heads and a FASt 102 intake w/LS2 throttlebody.

As general matter, the abence of headers (but with no cats or high-flow cats) will cost you 10-15 horsepower on a stock motor and 15-25 horsepower on a cammed motor depending on how much cam you would have run with headers as opposed to stock manifolds.

Its not too bad, it will cost you in the end, but you will still pick up a lot everywhere if you pick the right grind. FYI - the Thunder Racing CheaTR V.3 was made specifically for retaining the manifolds, but will still make more power if you get a free flowing exhaust.

Just make sure that the cam you pick has a pretty decent exhaust bias, in the neighborhood of 20* duration over the intake to account for expelling the exhaust gasses through a more restrictive system.

Cams installs are not too bad on our cars.