About 3 weeks ago I started putting together a DIY stage 4 fuel system. My goal was for this to be the last fuel system upgrade my car will ever need, and capable of flowing 900 whp worth of E85. Conceptually, this is the same idea as a Fuel-It stage 4, except the bypass lines are all in the tank and it won't hurt your wallet nearly as bad.
- Bucketless design with twin hydramats. Bucket is only to hold the pumps and float.
- Walbro 450 primary EKP-controlled pump. Feeds driver's side venturi to deliver fuel over the driveshaft hump. In-tank filter bypass.
- Walbro 525 secondary hobbs controlled pump. Full bypass of all in-tank restrictions.
- DIY wiring harness for secondary pump with 40A relay, hobbs switch, and inline fuses
- 6AN steel reinforced feed line with Fuelab 10-micron inline filter
- All fittings through top hat tapped, sealant applied, and loctited. I hated the fact my old DIY stage 3 would occasionally leak through the top hat
- Port injection with 750cc injectors, Precision Raceworks FPR and 6AN return line.
Whole system minus the feed line and inline filter:
Fuel pump bucket:
Lines underneath the car (am I a certified zip tie master tech yet?):
This build sponsored by Home Depot