I can cruise fine and the car is smooth. If I hold the car steady at say 65, if I roll the throttle to 70 I get a slight hesitation (almost feels like a misfire) then once at 70 it smooths out again.

Idle and Cruise smooth.

This happens when I roll on the throttle at any speed.

Under WOT, no knocks recorded.

This is a newly built 383 assembled at JMS Racing Engines. The programmer found a few anomalies with the previous program such as Injector #1 values set to a 0.0 multiplier off idle. That has been corrected.

He is currently using TTS Datamaster software. Is there any place in particular he should be looking to correct the misfire when I roll on the throttle.

Also, my BLMs are 114 at idle LT and 127 on ST.
However, at 2000 and 3000 I'm running lean with 138 LTs and the ST at 130.

These are Delphi #36 injectors which he has programmed to #34.

 

It always helps to know as much as possible about the engine. In this case, we know its a 383 witrh 36# injectors, and the fact you are using DataMaster tells us you are running an OBD-I PCM. Beyond that, we don't really know much. In this case, the cam specs become important, including the I/E durations and lobe separation angle.

Why not add a "Signature" with basic info about your car - year, model, engine, tranny and any major mods. Makes it a lot easier to help you.

 

http://www.cardomain.com/ride/2644517

95 Z28 / 1LE - T56

Induction - SLP CAI, K&N dual air filters, 58mm Edelbrock TB, TB Bypass

Valvetrain - Ported & Polished Trick Flow Heads by JMS Racing Engines, Manley Undercut Valves, Comp Cams Custom Grind, 1.6 RRs Pro Magnum, Manley Pushrods, Forged Stroker Crank, 5.85" H-Beam Rods, Beehive Valve Springs

Cam Specs - Lift 0.528 In / 0.576 Ex, Duration 270 In / 280 Ex, LSA 112.

Exhaust - Edelbrock Ceramic Coated TES Headers, Off Road Pipe, Ex. Insert Cone, Edelbrock Cat Back Exhaust

Ignition - Jacob's Ultra Pack Ignition, Coil, Trigger, MSD 8.5mm Plug Wires, NGK TR55 Iridium Plugs

Drivetrain - Hurst Short Throw Shifter, SLP Alum Driveshaft, LG Torque Arm, GM 4.10s with Eaton Posi, SLP Lightened Flywheel and Centerforce Dual-Friction Clutch Package

Thanks, hope this helps. I would add it to the Signature but it is a lot of data.

 

Just put the basics in the "signature". Look at what I did with mine... you know its not a basic setup... 381, TH400, shot of juice, and if you need more details you click on the link. Hard to believe you've been here for 8 years without a signature......

Do you have the duration at 0.050" lift?

 

Well, I'm somewhat of an old timer in that I don't know how to set up my own web page, but I can link them to Car Domain I suppose.

The Duration a 0.050 is: 218/230 LSA 112

Thanks for your help.

Also, is there a procedure to setting the MAF Calibration Tables? I've done a slight search but I'm only finding topical data, not procedural steps. Since it is a 383 from a 350, the flow rate has changed.

 

Going from 350 to 383 will not impact the MAF. However, your bigger cam will as will any head work, etc.

Shoot me an email/PM and I will send over a spreadsheet I developed to calibrate the MAF. However, I warn you, it was set up by me for me. This means it was not written for others to understand