New to Holley Sniper, Anyone With Experience?
 

I finally got my Sniper installed, starting & idling well with parameters within range according to the startup guide. Timing is 11° BTDC, IAC +/- 5%, Hot Idle bounces around 850 RPM +/- 30. I went for a test drive today and it seemed to be running well until the engine reached about 175°. After the engine got hot it started cutting out/sputtering/lurching under acceleration. If I kicked in into neutral it seemed to smooth out, but I would have to rev the engine much higher than normal and ease the clutch real slow to take off again. Even then it would cut out/sputter/lurch to get going again; it even died a couple of times. On restart, it would crank but it would not fire up right away like it did cold, and I would have to depress the gas pedal slightly to get it to fire (to my understanding I should not have to do that with EFI). I let it sit and cool off, then repeated the process a couple more times. I have a datalog of my last drive, but I don't know how to read the data (I know how to access the data, but I don't know what any of it means). Every time I try to upload the datalog here I get an "invalid file" error message.

Any Ideas what could be causing my acceleration issue and hard hot start?

Re: New to Holley Sniper, Anyone With Experience?
 

Can you describe the fuel system? Where's the pump, where's the regulator, where does the return branch off back to the tank, all of that?

I'm wondering if perhaps you're having a fueling issue once things warm up.

Re: New to Holley Sniper, Anyone With Experience?
 

Your engine control module is switching from closed loop , to open loop {self learn} when the engine reaches that temperature , I would talk to holley's tech line , are you sure you have the engine size right in the setup

Re: New to Holley Sniper, Anyone With Experience?
 

I'm sure my engine size is right in the setup, at least it was when I set it. Is the switch from open to closed loop common; is it part of the learning process? If not, how do I alleviate the problem?

Re: New to Holley Sniper, Anyone With Experience?
 

In case anyone else has this issue, I called Holley and talked to a rep there. I gave him the rundown on my symptoms and he suggested I increase fuel enrichment from 49 lb/hr to 53 lb/hr. I drove around a while and haven't had any problems with acceleration or hot since.

Re: New to Holley Sniper, Anyone With Experience?
 

Glad to see you got it resolved. If you don't mind I would like to ask you what tank you are running and which pump ? I am planning to run the sniper system also :chevy:

Re: New to Holley Sniper, Anyone With Experience?
 

I'm running a RCI 15 gallon aluminum fuel cell in the bed (http://www.jegs.com/i/RCI/821/2161A/10002/-1). I went with that because it comes fitted with sending, return, and vent ports. It sits between my driver's wheel well and front of the bed so I really haven't lost any bed space. If you go with something like that you'll need to make sure you order fuel line adapter fittings. I bought the Sniper Master Kit, which came with its own inline fuel pump (https://www.holley.com/products/fuel...s/parts/12-920).

I ordered all my stuff from Chris at efisystempro.com; he's got great customer service and will know what you need regardless of the setup you go with.