Holley Sniper

Green411 · #1 (**permalink**) 30-07-24, 05:07 PM

I forgot to say in the last post that the fuel pump is a bit noisy, too. I used a Holley 12-131 returnless drop-in fuel module, which has a 255 lph in-tank pump. I added a Hydra-Mat, too, in lieu of a reservoir/swirlpot. All seems to work very well.

David C · #2 (**permalink**) 30-07-24, 09:29 PM

Do you think it would be a good plan to put some neoprene or similar under the fuel tank and also between the straps and the tank?
Perhaps a bit of Dynamat on top of the tank to damp any ringing.

Green411 · #3 (**permalink**) 01-08-24, 05:42 PM

Hmmm......I must say I hadn't considered anything between straps and tank, or below tank, but I have put as much sound deadening as will fit between the tank front and seat back, and above tank.

David C · #4 (**permalink**) 01-08-24, 06:50 PM

Next time you have access I suggest you place a hand on the top of the tank with the pump running. If you notice any lowering of noise level then one or two pieces of Dynamat or similar about 6" squareish may well help. If you can feel the pump vibration then decoupling the tank from the bodywork with something resilient is worth a go.

Green411 · #5 (**permalink**) 17-08-24, 08:35 PM

Sorry David C, for some reason (ineptitude?) have only just seen this.
Sounds like sound advice.

David C · #6 (**permalink**) 04-06-25, 08:19 PM

I'm pleased to report that my 410 is now sporting a Sniper 2 fuel injection unit with hyperspark distributor. First impressions very good other than fairly loud injector tick. A returnless pump went in the tank without too much trouble. I re-jigged the wiring loom to tidy it up and moved the pump relay to the fuse board. The throttle linkage required a fair bit of measuring and a bit of fabrication but otherwise it was surprisingly straightforward.

Green411 · #7 (**permalink**) 05-06-25, 11:10 AM

David, thanks the update.
I hope it works out for you as well as it has done for me. Mine isn't perfect, I occasionally get a stall when pulling away from stop during warm-up if I open the throttle quickly, but that's about it. I've left the programming completely alone ie it's all self-learnt. Maybe a few goes at more throttle from standstill while it warms up will nudge it to learn more in that particular TPS/MAP/CTS/oxygen sensor combination? Or maybe I've got an air or exhaust leak somewhere? Must admit I've never bothered with any data-logging with it.
Also my (Holley in-tank) fuel pump is noisy, even with a full tank. But at least I know it's working!