LSA injectors and spark plugs

[joeko23]

Hey guys, looking for recommendations on what size fuel injectors I would need and spark plugs for my LSA. Also do the spark plugs need to be gapped? It’s a 15’ ZL1 pullout, only upgrade from stock is a 2.38” griptec pulley. Which according to other people’s experience should increase power from stock by about 100hp. I also put in a solid isolator and I have a much larger intercooler than stock to handle the extra heat. I also will be using a cts-v pump and vaporworx controller. I believe that’s all the info you guys need.

[andrewb70]

I would use the stock spark plugs and the stock gap. Did you ask Carl about injector size?

Andrew

[joeko23]

I did not, I’ll ask him next I guess. Thanks Andrew!

[andrewb70]

I did not, I’ll ask him next I guess. Thanks Andrew!

My guess is that 65 pounders should be sufficient.

Andrew

[joeko23]

I also was thinking 65lbs but the guys from camaro5 forum are suggesting 85lb. I’m not planning more mods in the future. The engine will probably make around 700hp at the crank.

[csouth]

I would have the factory ones resized to 95lbs by Fuel Injector Connection. They will send the test in information and the injector data. Lots of guys on the LSA group do that instead of spending the money on aftermarket injectors. I think its like $320 for a set to resize.

The reason I say 95lbs is because if you decide to change cam later you'll be set. I usually read where most people's fuel deficiency is the injector in not the pump.

https://fuelinjectorconnection.com/

[joeko23]

Maybe this is a stupid question, but would fuel economy suffer going from say 65lb to 85lb? For normal driving/highway cruising? My thought is obviously it would suffer but then again maybe the computer only injects the amount of fuel the engine needs for every given second so under normal driving fuel economy wouldn’t suffer?

[joeko23]

Also the local shop that will be doing the tuning said they prefers new Bosch FIC injectors. According to my research all injectors that are not stock size are drilled out. Does Bosch make injectors that are 85lb+?

[csouth]

Maybe this is a stupid question, but would fuel economy suffer going from say 65lb to 85lb? For normal driving/highway cruising? My thought is obviously it would suffer but then again maybe the computer only injects the amount of fuel the engine needs for every given second so under normal driving fuel economy wouldn’t suffer?

You're tuner will read set the fuel map so the motor will add fuel as needed likely based on MAP and engine RPM. of course when you go into boost that will change.


Also the local shop that will be doing the tuning said they prefers new Bosch FIC injectors. According to my research all injectors that are not stock size are drilled out. Does Bosch make injectors that are 85lb+?

I do not think they have an off the shelf injector that runs at 85lb.

[pannetron]

Need to know at what pressure (43 or 58 PSI) those injectors are rated and what fuel pressure you'll be running. IMHO, the 65 lb injectors will be enough if they're rated at 43 PSI and you'll be running more pressure... unless you plan on running E85. Some huge injectors have trouble squirting the tiny amounts of fuel needed for a stable idle. My LS9-clone engine likes TR7IX plugs, they come pre-gapped to 1.0 mm, about 0.040".