Will this hose work for both coolant and boost applications?

Yes. Silicone handles coolant temps and turbo boost pressure equally well. Just confirm your specific application matches the 4.00" diameter before ordering — this is the hose only, no adapters or fittings included.

Do I need clamps, and what size should I use?

Clamps are not included. You'll need hose clamps sized for a 4.00" OD hose — most builders use band clamps or T-bolt clamps in the 4.5–5.0" range. Test-fit your setup before tightening.

Can I use this as a direct OEM replacement, or does it need modification?

This is a universal silicone elbow — it's not a plug-and-play swap for any specific vehicle. Measure your existing hose routing and port locations to confirm the 4.00" diameter and 90-degree angle work for your setup.