Rembrant Posted July 11, 2021 Author Share Posted July 11, 2021 Where the sniper gets its following is its all self contained. The ECM and sensors are with in the unit itself and all you have to hook up is a key hot, battery hot, battery ground, and a rpm signal and you are running. Everything else is optional and adds to the ability of the sniper. Holley also makes the Terminator that has an externally mounted ECM that you can mount anywhere you choose but it involves bundles of wires and large connectors. The OE system you can run and Holley makes a Terminator wiring harness/ECM to hook up to the OE EFI system making it more like the sniper/terminator when it comes to tuning and data logging. If I had a OE EFI system I would go the Terminator ECM/harness route. You can now data log and make changes via a hand hell or through a laptop. But if I did not have EFI nor the EFI components I would go with the Sniper/Terminator as its more cost effective compared to sourcing OE EFI parts and then paying for the Terminator harness on top of it. I personally picked the 4150 Sniper, it looks like a Holley 4150 double pumper but that wasnt the reason why I picked it, I picked it as it was the only Sniper Holley had with the Ford kick down hook up for a C6 transmission. The plain Sniper doesnt have a Ford kick down but does have a TH250/350 / 700R4 attachment points. Same with the Edelbrock Proflow 4 which is true fuel injection, it does not have a Ford kick down attachment and you will have to run a universal throttle cable as the intake on the ProFlow 4 is a high rise air gap like style. FiTech I installed 4 of those units some 4/5 years ago now and had nothing but problems with them. Every one of them had failed injectors, every one of them required sitting on hold for 2 to 4 hours to get a walk through of tuning the FiTech as the system on FiTech is a bit more complicated than compared to the sniper. The Sniper complaints online are typically user installation error as Ive installed some 5 or 7 Snipers after we stopped selling FiTechs and havent had one come back with an actual issue. Had one come back but the guy swears up and down the FiTech is running lean causing his engine to over heat. Problem is the Sniper is idling at 12.8:1 which is a little rich so there is no way it is the Sniper causing that issue and the guy refused to let us pull the engine and do a tear down and find out why its over heating. I have heard FiTechs are better now but I havent installed any as the sniper is just such a better system in my eyes. FiTech is what I thought of years ago for my truck but after 4 installs all had injector failures I said nope. The main reason the FiTech system catches my eye is that it's smaller (they have the #30003 EFI kit, which is max 400HP). I will probably go with the Holley kit if I do anything at all, but it just bugs me that they don't have a small 4bbl version...they're all 200-650HP, or larger. My 302 (now 304, I guess) just barely made 300HP on the dyno, and 99% of my driving will likely only use half of that...or between 100-200HP. I am never going to be at 5500 RPM in this truck, ever. I spend most of my time in the 1500-2500 RPM range, and once in a while hit 3000 RPM. Maybe one of the Holley Sniper EFI 2300 kits would work better for me...just need the 2V to 4V adapter plate. I was reading about adding the progressive linkage to the 4bbl Sniper, and it seems like a great idea, but then I found out that the ported vacuum for the distributor advance is at the back of the unit. So, the progressive linkage is an excellent option, as long as you're not using traditional vacuum advance like I plan to. Hmmm....more reading is in order, I guess. Link to comment Share on other sites More sharing options...
85lebaront2 Posted July 11, 2021 Share Posted July 11, 2021 The main reason the FiTech system catches my eye is that it's smaller (they have the #30003 EFI kit, which is max 400HP). I will probably go with the Holley kit if I do anything at all, but it just bugs me that they don't have a small 4bbl version...they're all 200-650HP, or larger. My 302 (now 304, I guess) just barely made 300HP on the dyno, and 99% of my driving will likely only use half of that...or between 100-200HP. I am never going to be at 5500 RPM in this truck, ever. I spend most of my time in the 1500-2500 RPM range, and once in a while hit 3000 RPM. Maybe one of the Holley Sniper EFI 2300 kits would work better for me...just need the 2V to 4V adapter plate. I was reading about adding the progressive linkage to the 4bbl Sniper, and it seems like a great idea, but then I found out that the ported vacuum for the distributor advance is at the back of the unit. So, the progressive linkage is an excellent option, as long as you're not using traditional vacuum advance like I plan to. Hmmm....more reading is in order, I guess. Obviously like most aftermarket stuff it is aimed at brand C engines, the ones with the distributor on the wrong end. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 11, 2021 Share Posted July 11, 2021 The main reason the FiTech system catches my eye is that it's smaller (they have the #30003 EFI kit, which is max 400HP). I will probably go with the Holley kit if I do anything at all, but it just bugs me that they don't have a small 4bbl version...they're all 200-650HP, or larger. My 302 (now 304, I guess) just barely made 300HP on the dyno, and 99% of my driving will likely only use half of that...or between 100-200HP. I am never going to be at 5500 RPM in this truck, ever. I spend most of my time in the 1500-2500 RPM range, and once in a while hit 3000 RPM. Maybe one of the Holley Sniper EFI 2300 kits would work better for me...just need the 2V to 4V adapter plate. I was reading about adding the progressive linkage to the 4bbl Sniper, and it seems like a great idea, but then I found out that the ported vacuum for the distributor advance is at the back of the unit. So, the progressive linkage is an excellent option, as long as you're not using traditional vacuum advance like I plan to. Hmmm....more reading is in order, I guess. You dont need progressive linkage. Holley in facts stresses to not do progressive linkage as the sniper is designed to work on all four barrels at the same time. The fix Holley came up with for correcting the stiff pedal and the sharp break away when trying to lightly apply throttle to leave a red light where it goes from 0% TPS to 50% TPS is the throttle extension lever which is what I bought. I've installed these in all vehicles with a stiff pedal and it fixed the problem to the point where it feels like you almost dont even have a return spring in most cases due to the extra mechanical advantage it gives you. On the power output, long as you are over 200hp the sniper will work great. Look at it like this, the less fuel you need the shorter pulse width the injectors will operate at which means less heat in the injectors and more longevity. Like wise you are correct, the timed spark port or ported vacuum operates on the back two throttle bores and the use of a progressive linkage will delay vacuum advance. I believe the Sniper Stealth is the same way as ported vacuum is still on the back of the throttle body. How ever where the Sniper Stealth is better is the manifold vacuum port for PCV/brake booster is situated on the rear bores just like the standard Sniper but the IAC is relocated from the rear bores to the front bores. This actually removes the risk of gumming up from the pcv fumes being sucked past and through the IAC. This is why I will be using the rear manifold vacuum port for PCV and be using the OE vacuum tree in cylinder 4 intake runner for my brake booster. I may run a Tee and run my brake booster to the PCV line but I dont want to be using multiple tees as that increases the risk of vacuum leaks over time. For my build, most of my driving will be 1,400/1,500 rpm to 2,750 rpm which is street driving and highway driving up to 75 mph. The cam I am running makes power 1,400 - 5,400 rpm and we all know the C6 transmisison out of the factory shifts out at wide open throttle at 4,500 rpm. I will be having broader performance here in Texas custom build me a C6 with a E40D planetary gear set along with him tweaking the governor to get me a 5,000 to 5,500 rpm wide open throttle shift point. My cam with recommended valve springs will float the valves at 6,000. The springs I got from AFR are like 10 lbs heavier than recommended so I should be good there and my roller lifters are the 302H rollers that are supposed to be stable to 6,500 rpm. I feel the sniper will be a great addition to my build and my goal was always 300hp but realistically if everything works right I could very well see 375hp or like the engine builder I know he says I might even hit 400hp if I am lucky. I dont want that much power though cause this is a truck that will be driven empty 80% of the time. The FiTech does have a smaller system for the 4V setups, Holley goes to a 2V setup for lower power engines which does suck for people with a 4V intake. Both FiTech and Holley uses GM components, for example FiTech uses LS6 injectors last I heard. Holley uses GM injectors but I dont know what they are for. Holley wont really give us the correct part number for the injectors but we know they are GM though. The TPS and IAC are both GM as well so sourcing parts for many things is actually quite easy as you just pick up a GM part from the local part store. The Injectors on the holley is a bit harder cause they swear the injectors are special built for them but FiTech told us the same thing but then told us that they are basically LS6 injectors another time. So I dont think Holley has special injectors either they just dont want us taking the units apart and servicing them ourselves vs mailing them back in for repair. But I think the sniper would work great for you regardless of how much power your engine is making. I doubt that 327 sbc I threw the sniper on was making much over 300hp if it was even making 300hp and it ran great. Was very throttle responsive more so than the OE 4V carb. It also idled so much smoother with the IAC taking over to maintain idle speed vs the mechanical idle speed stop. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 11, 2021 Share Posted July 11, 2021 Obviously like most aftermarket stuff it is aimed at brand C engines, the ones with the distributor on the wrong end. The standard sniper is as it doesnt have a ford kickdown linkage for Ford automatics. The Sniper Stealth actually has the Ford kick down linkage so I feel the Sniper Stealth 4150 is more of a universal setup designed to also work with Ford automatic transmissions why the standard sniper is more geared towards just chevrolet setups. You could still make the standard sniper work with switching the ford kick down to a cable and attaching the cable to one of the holes for the TH250/350 or 700R4 throttle cable hook ups. Link to comment Share on other sites More sharing options...
Rembrant Posted July 16, 2021 Author Share Posted July 16, 2021 The fix Holley came up with for correcting the stiff pedal and the sharp break away when trying to lightly apply throttle to leave a red light where it goes from 0% TPS to 50% TPS is the throttle extension lever which is what I bought. I've installed these in all vehicles with a stiff pedal and it fixed the problem to the point where it feels like you almost dont even have a return spring in most cases due to the extra mechanical advantage it gives you. Is this the throttle extension that you're talking about? https://www.holley.com/products/fuel_systems/carburetor_components/brackets_and_linkage/parts/1952 Link to comment Share on other sites More sharing options...
Rembrant Posted July 16, 2021 Author Share Posted July 16, 2021 Guys, I'm still reading and researching stuff here, and I see that Rusty plans to use a 1985-1986 sending unit, and Jacob used a 1995 fuel tank and sending unit. Does the 1995 EFI tank sending unit have the same inlet and outlet connection sizes? 3/8 and 5/16? Link to comment Share on other sites More sharing options...
Gary Lewis Posted July 16, 2021 Share Posted July 16, 2021 Guys, I'm still reading and researching stuff here, and I see that Rusty plans to use a 1985-1986 sending unit, and Jacob used a 1995 fuel tank and sending unit. Does the 1995 EFI tank sending unit have the same inlet and outlet connection sizes? 3/8 and 5/16? Yes, the later tanks use 3/8” and 5/16” fittings. But they are the quick-disconnect style. And, Dorman sells the connectors for both that use 3/8” nylon tubing, so I bought a 20’ roll and did everything with it. Link to comment Share on other sites More sharing options...
Rembrant Posted July 16, 2021 Author Share Posted July 16, 2021 Yes, the later tanks use 3/8” and 5/16” fittings. But they are the quick-disconnect style. And, Dorman sells the connectors for both that use 3/8” nylon tubing, so I bought a 20’ roll and did everything with it. Oh...I was looking at the Earl's fittings and vapor guard hose...I didn't know you could buy fittings to do it with the nylon hose...hmmmm...very interesting, thanks Gary. I'm off to go search for Dorman fittings I guess...haha. Link to comment Share on other sites More sharing options...
Gary Lewis Posted July 16, 2021 Share Posted July 16, 2021 Oh...I was looking at the Earl's fittings and vapor guard hose...I didn't know you could buy fittings to do it with the nylon hose...hmmmm...very interesting, thanks Gary. I'm off to go search for Dorman fittings I guess...haha. Search in Big Blue’s Transformation thread for Dorman. There’re are part numbers, etc. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 16, 2021 Share Posted July 16, 2021 The fix Holley came up with for correcting the stiff pedal and the sharp break away when trying to lightly apply throttle to leave a red light where it goes from 0% TPS to 50% TPS is the throttle extension lever which is what I bought. I've installed these in all vehicles with a stiff pedal and it fixed the problem to the point where it feels like you almost dont even have a return spring in most cases due to the extra mechanical advantage it gives you. Is this the throttle extension that you're talking about? https://www.holley.com/products/fuel_systems/carburetor_components/brackets_and_linkage/parts/1952 Nope this is it here. https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/sniper_efi_service_components/parts/20-16 Link to comment Share on other sites More sharing options...
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