It’s in all caps and in a big black box in the instructions.
Kinda like a sticky at the top of the forum. It must be invisible.
Holley Sniper EFI : Tips / Tricks / Modifications
- Thread starter knuckle47
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Kinda like a sticky at the top of the forum. It must be invisible.
MOTOV8R
SILVER Star
This is what my instructions looked like. At the time I just wanted it to stop being at the 2500 rpm it started at out of the box. So found the idle adjustment screw and dialed it in to 650 rpm after it was above 165 F. I never looked at the IAC display until yesterday.
Since this is a FAQ style thread, just to be clear. That is not the idle screw. The idle is set by the computer, whatever you decided you wanted it to be during the Wizard.
From experience I’ve been doing 750-800 depending on the patient. Some like to fight when warming up by dying at stoplights pre-165 and those usually get a higher base RPM
What you adjusted was the IAC screw. You just happened to nail it without knowing it.
For those that are doing a first start.
1) Run Wizard
2) Crank
3) check for vacuum leaks (high idle)
4) Pinch off vacuum advance from dissy and set timing. I think the DUI/Sniper likes 10-12 degree advance on average. I’ve had one go as high as 16*
5) once at 165 degrees adjust your IAC. If the TPS starts to creep up. Turn it off and restart it. That should reset to zero.
- Thread starter
- #24
After trying the technique told to me by Holley Tech Support…it seems to have worked…took a few up and down adjustment of the RPM and pumping the throttle here and there but this has been a pretty steady read out for about 6 minutes….never had that before. Now I can put the radio back and tidy up the rest of the wires behind it
When you shut it off and back on see if the TPS goes to zero.
- Thread starter
- #26
@wngrog … you may find this funny… I mentioned I have a LINKS page in the computer to reference all of the Sniper installs and adjustments on videos etc. I was just on your install of Texas Red…page 3 post number 59 where you explain how the IAC was out of whack due to a previous vacuum leak and what to do to fix it….word for word from Holley in the phone conversation I had with them on Thursday…
Anyhow, the TPS did zero out on restart. I also bought a new timing light where you can set your advance and follow the bead in the observation window. I believed it was set to 8-9 degrees BTDC..,it was at 5. Brought it up to 10. Running nicely. I might try 12 but I’ll let it run a few days before I do that. With this new timing light, you can drop a degree or 2 and see the BB drop behind the pointer and then bring it back up and over for more advance. I’m sure you have one. I hadn’t bought a timing light since the mid 1970’s
Regardless, thanks again for pointing me in the right direction
Anyhow, the TPS did zero out on restart. I also bought a new timing light where you can set your advance and follow the bead in the observation window. I believed it was set to 8-9 degrees BTDC..,it was at 5. Brought it up to 10. Running nicely. I might try 12 but I’ll let it run a few days before I do that. With this new timing light, you can drop a degree or 2 and see the BB drop behind the pointer and then bring it back up and over for more advance. I’m sure you have one. I hadn’t bought a timing light since the mid 1970’s
Regardless, thanks again for pointing me in the right direction
Can you give an idea of how much you spent to convert to the Holley Sniper, and how difficult you thought it was to install?
- Thread starter
- #28
Absolutely…. I bought the entire package from Mosley Motors. It included everything from the in-tank pump, hoses, EFI unit, Bosch O2 sensor and weld-in OR bolt in fittings…, wiring, AN fuel fittings, clamps, fuel pump block-off plate and the Lokar throttle linkage assembly. I added a few things like Earl’s fuel pressure gauge from Holley or Amazon. I bought this about 18 months ago and I think it was all around $2400.
I also used about 12’ of 3/8 copper-nickel hard fuel line along the chassis rails.
As for difficulty…not a challenge as it is mostly screw this here and bolt that onto this type stuff. You need to use good judgement regarding wiring And the connection you make and they show you what NOT TO DO. For me…the biggest issue was to understand that the “carb idle screw” IS NOT A CARB IDLE SCREW!
The computer controls the throttle idle speed….that screw needs a new name. But you can down load and read the manual and quick start manual from the Holley web site. It will truly clue you in. Also watch this post and the embedded videos from @wngrog …. Made me think differently …finally
Builds - Texas Reds - The Tale of Two Red 40’s - https://forum.ih8mud.com/threads/texas-reds-the-tale-of-two-red-40s.1193989/page-2#post-12925703
I also used about 12’ of 3/8 copper-nickel hard fuel line along the chassis rails.
As for difficulty…not a challenge as it is mostly screw this here and bolt that onto this type stuff. You need to use good judgement regarding wiring And the connection you make and they show you what NOT TO DO. For me…the biggest issue was to understand that the “carb idle screw” IS NOT A CARB IDLE SCREW!
The computer controls the throttle idle speed….that screw needs a new name. But you can down load and read the manual and quick start manual from the Holley web site. It will truly clue you in. Also watch this post and the embedded videos from @wngrog …. Made me think differently …finally
Builds - Texas Reds - The Tale of Two Red 40’s - https://forum.ih8mud.com/threads/texas-reds-the-tale-of-two-red-40s.1193989/page-2#post-12925703
Thanks for the info! This is at the top of my list for mods I want to do.
I found the addition of the Holley Hyperspark to the Sniper to be useful. The ability to adjust spark advance as part of the fuel mapping process has made for a motor that runs as smoothly as my 2019 Toyota. Starts immediately whether it is 20F outside or heat soaked on a 100F day. See the posts from zerotreedelta on how to modify a Hyperspark distributor to fit into a F/2F motor or you can buy one already modified from Moseley.
- Thread starter
- #32
I had thought about the hyper spark and would enjoy the timing being controlled by the EFI…not too clear on what I’d need to undo with wiring. My 2F is running very well on the other hand, I said that same thing when it was running the Weber carb.
I have seen that YouTube video from Lone Wolf. Looks interesting and that erroneous timing gauge on the hand held would actually mean something
I have seen that YouTube video from Lone Wolf. Looks interesting and that erroneous timing gauge on the hand held would actually mean something
Wiring was pretty straightforward. Just follow the instructions that came with the Sniper. (Ground, +12V switched, timing wire from Sniper - wiring to coil is a plug-in connector.) The Sniper will take over control of the timing. Minor fabrication of mounts needed to hold the Hyperspark box and coil in place. I used rivnuts to mount them to the firewall. You will also need new spark plug cables since the connectors Holley used on the distributor are different than the connectors on the OEM distributor. I just bought these from Moseley, they are pretty standard. I would guess even NAPA sells a set that could be cut to length. The most difficult part of the install is the distributor. You have to use the Hyperspark distributor and Holley doesn't sell one with the correct diameter shaft and gear. Onetreedelta has a video showing how to make your own or, again, you can buy one that is modified from Moseley. If you make your own, it is a simple turning operation on the lathe and a gear change on the bottom - just use the gear off your old distributor.
On setting the timing, you simply use the menu on the Sniper to lock timing to a fixed advance then rotate the distributor until the BB lines up with the marker. That sets your base timing. The Sniper software takes over after that. You only need a simple timing strobe light.
It's just the terminals on the top of the Hyperspark distributor are male (not sure the proper term) and the original Toyota distributor had the other kind. So, you would likely need to get a new set of end connections to crimp on. See photo below of Hyperspark distributor. Sorry for not knowing the proper term for this type of connector.
Livewires work with Hyperspark setup. You will need a longer coil wire to connect them
- Thread starter
- #38
After reading and re-reading about the Holley Hyperspark, I checked with Mosley yesterday…they sent me an invoice for the masterkit and I decided to do it. This might prove to be fruitless based on the DUI currently installed ( it runs great) but I do enjoy working on the truck and 95% of the other stuff has been done.
Steering knuckles are next but not super critical and I really want to replace the ambulance door window rubbers and front windshield. Hopefully the Hyperspark may be here in a few days and we can all get started. No one here in my locale has any interests in this stuff ( they’re all a different type of retirement crowd) besides a hot rod friend who loves any kinds of modifications…so…you guys are it.
Not the cheapest add-on mod but I am 71 and waiting does little for me..so consider the time line, and let’s go for it
Steering knuckles are next but not super critical and I really want to replace the ambulance door window rubbers and front windshield. Hopefully the Hyperspark may be here in a few days and we can all get started. No one here in my locale has any interests in this stuff ( they’re all a different type of retirement crowd) besides a hot rod friend who loves any kinds of modifications…so…you guys are it.
Not the cheapest add-on mod but I am 71 and waiting does little for me..so consider the time line, and let’s go for it
cstav86
SILVER Star
Will be following along and interested to see how it goes.
That’s great news. I’m waiting to see just what improvements you can get out of it. I just picked up a DUI unit so let us know.
