Ok you need to know that you are working with gasoline engine must be cold and lots of rags and fire ext to put out the fire.
A stock fuel presure regulator for an L98 should read 40 psi at idle with the vacum line disconected,
a stock LT1 is around 43.5 psi at idle and vac line disconected.
With your allen wrench and open end wrench 1/2 inch or 9/16 you will need to losen your allen head nut to adjust fuel pressure.
Vacum disconected and engine running at idle the higher fuel presure will increase the fuel to the engine sortof what it realy doe's is atomize the fuel more and in doing so the extra fuel is needed.
To much information to realy understand but the highest I have seen on a stock motor is 46 psi.
If you are using an aeromotive regulator and it does not adjust then where the vac nipple is you will have to grind it down, if using an accel regulator bye bye motor within 12 hours .
The motor will fill with fuel and the engine will lock up.
If you are building your own check the rubber to make sure there are no holes in it.

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