BWilcox

Hi Guys,

I have finally completed enough tasks with the car to start the ECM tuning phase.

Here is a short set-up summary:

420 CID.
TPIS MiniRam II.
TPIS ZZ-X Cam.
AFR Heads.
Aeromotive Stealth 340 Fuel Pump.
Bosch III 42 Lb/Hr Injectors
4" Intake.
3" True Dual Exhaust with X-Pipe (after dual RT High FLow Cat-Cons).

When the engine is off and the fuel pump is running continuously, I can set the fuel pressure to 48 PSIG. A very steady reading. Although, the fuel flow makes a fair amount of noise in the hard line.

I made hard line from the back of the MiniRam II to the front of the drivers side cylinder head. A bracket with -6AN bulkhead conenctors is utilized to support the connection from the custom hard-line to the PTFE braided steel line.

When the engine is at idle, the fuel pressure bounces around from roughly low 40's PSIG to high forty's PSIG.

Removing the AFPR vacuum port does not help.

The idle MAP ranges from 66 kPa to 70 kPa at 800 RPM. Roughly 19.5 " hg to 20.7 " hg. Where I live, the atmospheric pressure is around 29.5" hg. So my idle vacuum range is ~9" hg to ~10" hg.

The ECM that I am running is the 7730.

The idle PW is aorund 2 mS.

Is it normal for larger injectors / large motor to create this pulsing effect?

Is my home-made hard line (source - 3/8", return - 5/16") the issue?

The car seems to drive well based on the dyno tune. Based on the WBO2 and the BLM, I need to tune the VE tables to account for the Intake and Exhaust restriction when compared to the Dyno.

Best Regards,

Bruce