I have posted in here before getting advise on a dry set up that i just couldnt get it to work I gave up and went to wet well we are back at it again, I am helping a friend with his car Jeremy formato is tunning it.

Old set up was 346 cam only with bolt ons and a 125 dry shot that worked great untill rod bearing failure,

New set up is 383 small bore, 5.3 heads and a big cam, 90mm fast everything else the same as before,

The dry kit is as it was when it worked fine on the 346 but now on the 383 it is too lean its like the maf doesnt see the n20, afr was 12.5 untill the dry came on it spiked 14.8 then falls to 13.9 but doesnt drop any lower
If anyone has any input please chim in

 

Sure its not in need of more fuel supply since the larger cubes? Is the MAF dirty?

 

We are sure it has 42's and the fuel system is up to par the maf was clean

 

I just did some looking at the tune and i'm thinking something is up here

The VE tables are exactly what they where with the old 346 tune this doesnt sound right to me but anyway looking at the PE table the cammanded afr is13.7 at 4800 rmp and 14.06 at 6000 and above shouldnt the PE been set closer to 12.8-13.1 the the VE tables adjusted to get the desired AFR? Would this affect the fueling for the dry shot? On the dry shot AFR was very close to the cammanded AFR of 13.7 at that rmp

 

Has the tuner (or have you) adjusted the physical size of the engine in the tuning parameters, under general you can change from 346 to xxxx by liter per cyl caculations, which once set should alter the VE and other tables. Then yes, get into your PE table and make the necessary adjustments to reach target AFR.