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Holley EFI, Sniper or Stealth sniper

Thx threewood

I've seen your thread about your installation.
I went with a OEM style pick-up with in-tank pump.
This kit has a build in regulator so i only needed to run a single 3/8" fuel line with filter assembly to the engine bay which was very easy compared to any external regulator or return line.
Starting i guess will be something i will need to spend quite some time on to get it right, my engine only produces around 7-8" hg vacuum so even for the EFI it is not easy to keep that going when cold.
When the engine is at normal operating temperature it runs fine, but that was the same with the carb.
 
Thx threewood

I've seen your thread about your installation.
I went with a OEM style pick-up with in-tank pump.
This kit has a build in regulator so i only needed to run a single 3/8" fuel line with filter assembly to the engine bay which was very easy compared to any external regulator or return line.
Starting i guess will be something i will need to spend quite some time on to get it right, my engine only produces around 7-8" hg vacuum so even for the EFI it is not easy to keep that going when cold.
When the engine is at normal operating temperature it runs fine, but that was the same with the carb.

EFI should be easy to tune for cold starts. If it is a Holley EFI system then you just need to adjust the cold start tables. Turn the data log on before you crank the engine when it is cold. Data log the entire cold start and then carefully review the data log. Look at all of the temp enrichments, look at the CL comp, pay attention to the target AFR vs. the actual AFR. You'll figure it out.
 
Thx Andy,

I will indeed look into the cold starts.
I did notice the IAC was showing really high values in the beginning to allow sufficient air in to let it idle at "high idle" speed but it could not manage as it run out of adjustment.
Guess i can play a bit with the adjustable Wagner PCV to let some more air in, when time and weather allows i will go play around with it.
 
Glad it worked out!! Probably a bit more enjoyable to start and drive.

The enjoyable for drive is 100% for sure, no stumble, bog or whatsoever and power from idle to WOT, spend some time today driving after being away for work for 8 weeks.
Only thing is the starting remains drama, it really struggles.
I upped the pump shot prior to start from 150% to 200%, even then need to cycle the ignition 3x to get sufficient fuel down hole to get it to fire.
Idle is a big struggle, it's not able to bring up the high idle rpm for some reason, i set it to 1250 rpm to idle until the coolant starts to warm up, then it will ramp down to 780 rpm.
But the idle remains low and in the end will run very poor.
Warm idle is also hunting, it struggles to maintain the set rpm, i can see the IAC is coming down to 2-5%, then the idle rpm comes down so it opens up again to 20%.
Maybe this has to do with the IAC response time and it needs to act a little slower.
Idle AFR target is set for 13.0, i will have to try again and see if it helps if i enrich it a bit more.

Still lots to read and play, hopefully i will be able to improve things a bit more.
Driving is a different story, once at operating temperature it drives like a rocket!
 
my vote is for the MSD (Holley) Atomic EFI 2. i’m biased since my Atomic EFI has been running well since it got installed (maybe about 7-8 years now)

forget my recommendation above. looks like you are up and running. glad to be of assistance.

:thumbsup:






watermelon
 
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