Jetting question for 780 cfm before dyno run

[aj]

Need suggestions for jet sizes for an upcoming dyno run using a 780 vac secondary with single power valve on pretty tame 465 CJ

The dyno session will be brief (mostly to break in motor and leak check) so limited opportunity to dial in jetting....maybe just 1 swap.

The motor is fairly tame 465 CJ with mild Lykins hyd. roller, mild ported CJ heads, stock CJ intake.  Will dyno with headers but eventually running stock CJ manifolds in the car.

Elevation <1000 feet.

Stock jetting for  735 on a 428CJ is 66/79.
Stock jetting for 780 (in B302) is    71/82.

Since I'm cross pollinating the 780 onto the CJ...not sure which jets to use.  My gut says leave the 71/82 in the 780 but purely a guess.

I wouldn't be splitting hairs but unfortunately I wont have time to fiddle around much with the jets so am trying to get as close as possible on the first swing.

Hoping guys with dyno experience might have good ballpark numbers.

Thanks all
Adrian




 

[427LX]

I would try the stock jetting 71/82

[My427stang]

Use 780 jetting or add 2 numbers to secondaries to give a little insurance at WOT on the first pull don’t go smaller