3" downpipe will fit both ko3 and ko3s. As for your other mods it really depends on the kind of power you're aiming for.
Before you do anything make sure the engine is running well, as a minimum I'd do an oil/filter change and check for split boost pipes. When were the cambelt/waterpump last done? Waterpumps are renowned for failing. Oil pickup pipes also get blocked so is worth replacing if there is no record of it being done.
Once the car is running ok then look at mods, either forge d/v will be fine, TIP is a must, personally I'd get a full hose set as well, forge and ths intercoolers fit well, alternatively search for 'wellycooler' and take a look. I'd also think about air intake, again there's a comprehensive thread about if already if you search.
What power are you aiming for?
Thanks for that info dom. I will be changing cambelt waterpump and full service the car. What tip should i get?
im aiming for 300 horses. Thinking k03s hybrid??
Will be getting silicone hoses with a sprinter fmic.
I was reading about the s2000 filter (its on my watch list) lols
Thanks to other who are helpint me out with sound advise
I'd ditch the idea of a sprinter fmic, the cores are rubbish, especially if you're going for 300bhp. I'd also be looking at a Badger5 TIP, S2000 filter is a good setup but as far as I know it hasn't been tested on big power cars. I'd look into the R-tech induction kits that they sell.
If you're going for 300bhp it won't be cheap, you'll need fuel pump, injectors and a full exhaust/decat, you're also around the power/torque that will bend rods
