Sniper EFI conversion

[LC2NLS6]

You should be able to run the factory GM dist without having to get the hyperspark setup, but I wanted all new stuff, so.

 

[Erik the Awful]

Has anyone made any progress on these builds? I bought the cheaper Summit Racing EFI system, and so far, it is identical to the FiTech system. I am curious how you guys plan on doing your factory cruise control, throttle cable, and TV cables?

Mine runs and drives. I used Summit's Holley bracket. After I opened it I discovered the instructions say it shouldn't work, but it does. I don't have cruise control yet, but I'll work on that after I finish rebuilding the original 700R4 - I have a junkyard 700R4 in it now.

 

[AG2320]

So I got mine broke-in over the weekend, but I had a few minor issues and one ground issue. It seems that the ground strap to the block isn't getting a good enough connection because it was grounding out through the oil dipstick tube resting on the master cylinder. Ran great though! Haha.

 

[ccreddell]

Im still putting it together. I have to replace my whole fuel system (because I wanted to), and Im doing it in the driveway. Heat in the PNW has been 102-105 for a couple weeks now, so that has slowed me down. But hopefully soon....

 

[Wheeler]

I had NOTHING BUT TROUBLE with the sniper EFI & Hyperspark dizzy. I wired everything 110% & always had hard start issues as well as other issues. I had it dyno tuned at 2 different shops. The second made it a lot better, but still issues.. I gave up, swapped out to a carb, & been happy ever since! NO electronics to deal with!!! So I’m not sure what was the deal with my set up, but I hated it. Nothing but issues. The shop I deal with now installs fast, sniper ect all the time… they encounter that though all the time… some work amazing, others nothing BUT issues…

 

[alignman88]

I had NOTHING BUT TROUBLE with the sniper EFI & Hyperspark dizzy. I wired everything 110% & always had hard start issues as well as other issues. I had it dyno tuned at 2 different shops. The second made it a lot better, but still issues.. I gave up, swapped out to a carb, & been happy ever since! NO electronics to deal with!!! So I’m not sure what was the deal with my set up, but I hated it. Nothing but issues. The shop I deal with now installs fast, sniper ect all the time… they encounter that though all the time… some work amazing, others nothing BUT issues…

Unless it’s a bad ECU or component out of the box, and EFI system will work well as long as ZERO preexisting conditions are present. Minor exhaust leaks, vacuum leaks, not enough GOOD grounds can’t hide from the EFI like it can be tolerated by a carb. Granted it feels like picking fly **** out of pepper but in this case you’ll taste it no matter how small it is

 

[Wheeler]

Everything on my set up was 110% verified. I had one made in a Friday late afternoon….

 

[Erik the Awful]

90% of the problems I read about on the Sniper are vacuum and exhaust leaks. I had a header gasket leak at first, tightened it up, and mine runs like a top.

 

[smurfcivic]

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I literally just installed mine last week. Truck was already carbed so install was easy. Just trying to figure out the wiring for the ac and fans now.

 

[alignman88]

If you have a 700r4 transmission how is converter lockup controlled after carb swap?

My 88 ECM uses TPS, RPM and VSS as inputs to trigger lockup. I haven’t found mention of MAP sensor usage. Even tho they all say don’t do it WHY can’t you use TPS breakout adapter and attach ECM wire to Sniper TPS signal? The idea of remote TPS I don’t care for. Also you would have ability to use cruise control, maybe that would use a MAP sensor which is easy to use stock one and it’s wires. I’ve saved the wires to this point. Would be great to hear if anyone has managed converter lockup with Sniper and factory ECM, or knows better and will talk me out of it