Gary M

Anyone have opinions or experience with this combo on a 455 cutlass? In my case 4 speed. W-30 cam and intake, ported and blended big valve E heads and WZ exhaust manifolds.
Will the tic toc tachometer work with it?

Issues other than needing an adapter for the throttle for smooth operation?

thanks

matt69olds

The factory tach works fine in my car with the Holley stuff. I'm using a MSD-6AL ignition box to trigger the ignition.

maddoctor

The master is the550-516K4. Includes the dist, fuel pump, fittings. Do yourself a favour and go online and print off the long version of the instructions.

maddoctor

the tech will be fine, I have an original tic toc set in mine. I left mine wired as it was, no connection to the efi.

theboz001

I just completed the installation of both the Sniper and Dual-Sync on my 72 Cutlass.

Aside from a few issues with the built in regulator and the latest firmware update causing it to dump fuel but those were the only major issues. Way more responsive than the 750 Holley I had on before. Overall, very happy with the performance. Just a few hiccups along the way.

Definitely get the throttle extension and save time by getting a fitting with a port for a pressure gauge. If you have to call Holley with any issue the first thing they will ask is what is the fuel pressure. Also if you use the external fuel pump you will want to pick up some rubber isolators to put between the fuel pump and whatever you are mounting it to. Otherwise its extremely noisy.

Throttle extension = Demon part number 1952
6AN fitting with port for pressure gauge = Earls Plumbing AT100199ERL
Rubber isolator mounts = https://www.ebay.com/itm/4pcs-M6-M8-...72.m2749.l2649

You will also need the special adapter that goes from the dual-sync to the Sniper harness. PN:558-493
If you plan to tune with your laptop be sure to order the CAN-USB cable. PN:558-443
The coil driver is also no longer included in the kit. PN: 556-150
The master kit no longer comes with the throttle cable adapters, so if you need them you have to order separately.
Throttle ball adapter kit = PN: 20-2
1/4" throttle stud kit = PN: 20-38
7/32" throttle stud kit = PN: 20-37

I cannot comprehend why Holley wouldn't include these items as part of the "master kit" or even list them on the Sniper page as recommended components. It was extremely frustrating to order the kit only to find out that I still needed to order more stuff to complete the installation.

I found an extension cable that goes between the Sniper and handheld/canbus cable. Using this I can swap between the handheld and laptop without opening the hood. Available here --> https://www.efisystempro.com/sniper/...harness-4-feet

The extension cable Holley sells has the same connector on both ends. This was the only place that had a true extension cable.

High 11s

matt69olds

mmbuffny

Thanks for all the valuable information. Was the conversion worth the money? How is the drivability of the car now? Start up easier and more responsive? Thanks

Olds64

Matt, was dealing with Holley customer service a problem. I was considering the Holley Sniper as well because everything I've heard about the FiTech is that their customer service is non existent.

Too bad there are so many additional parts needed in addition to the master kit. I guess the master kit isn't "master" at all.

Mr Nick

I have the Sniper as well, had FAST EZ-EFI before it. The Sniper is far superior.

I prefer an in-tank pump, so I got the regular kit and a new EFI tank from Tanks Inc and drop in pump assembly. http://www.tanksinc.com/index.cfm/pa...cat/cat153.htm

Gary M

Mine was used once on the dyno then put back in the boxes. Sold as used once. Buyer found distributor was defective from the ride, oxygen sensor was shot from being dry for a few months in the box and the carb unit computer would not keep the program. Had to refund the money and take a loss. The buyer also lost alot of money trying to make it work. Dont think I would buy another one unless I plan to use right away. The distributor that I got was discontinued because alot of buyers had issues.

cutlassefi

Someone has this backwards. Moisture in the tip causes failure, not dryness. That’s why they recommend installing it so that the tip isn’t sideways or facing up at all.

Gary M

I went by what the buyer said customer service told him. It was in the box after running fine on the dyno so who knows what or who caused the stuff to fail. Dyno, shipping, install....? It seems a little delicate to me if the ride and storage killed it. I was told Holley service said the units have a shelf life of a few months. If that's the case it seems they would go bad on the cars in storage over the winter. Other people seem happy with theirs but my experience was not good regardless of why it happened. If no other reviewers tell same story as me then it's probably a good system. Sometimes bad things happen that you cant determine how or who caused them. As a seller of the used unit I did the right thing for the buyer.