At present my 94 SC400 is completely stock, but I am looking to increase output to 300-400 hp. What are the most affordable, and least harmful engine mods that can help me achieve this?

 

The least expensive way to get to 300whp on a 400 will probably be to supercharge it. A few people around here are running eaton m90's and are making pretty good numbers. With some headers and a good tune you can probably achieve your goal.

 

lots of ways to make power, how much you planning on spending?....dont need much boost to make good power with the V8 motor, or maybe a little happy juice

 

2000-3000 dollars

I'm a little strapped on cash as of right now...

I've come across, some options, such as BFI, ecu, magnaflow exhaust and headers.

Anything else?

Positive and negatives of supercharging vs. turbo?

 

A BFI, headers and full exhaust will probably only get you ~200 to the wheels. I think stock, the non vvti 1uz puts down around 180whp.

 

i kinda just bought another 72mm turbo... want one?

 

cheapest way custom cold air intake to the fenderwell, long tube headers out to 3inch, LSD rear end, w58/r154/t-5 5-speed transmission. runs more efficient 5-speed anyways. supercharged correctly your looking around 2-3k if you know what your doing if not 5-6k. 5speed swap 2k-3.5k