Injectors too small
Thread Starter
Staging Lane
Joined: Mar 2019
Posts: 51
Likes: 10
Injectors too small I have a daily driver silverado with an lq9 in it. I put 243 heads, stage III high lift cam, and TBSS intake. It has the stock injectors that are maxed out. What is a good injector to get for my application, I know very little about it. Thankyou
TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
WHOSE Stage III high lift cam? Everybody's spec is different.
The 243 heads have the same ports as the 317's that came out. So the cam is the main difference
How do you know the present injectors are maxed out?
The 243 heads have the same ports as the 317's that came out. So the cam is the main difference
How do you know the present injectors are maxed out?
TECH Enthusiast
Joined: Mar 2005
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From: South Carolina
Thread Starter
Staging Lane
Joined: Mar 2019
Posts: 51
Likes: 10
TECH Fanatic
Joined: Jan 2022
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From: Seattle
Use this to find out what size injectors (lb/hr) you need, then work backwards to figure out what frame size, and what connector that works with your application.
https://documents.holley.com/techlib...l_injector.pdf
here’s a good link to learn about injector frame (dimension) differences
https://www.ictbillet.com/swap-guide...e.html#cat-567
https://documents.holley.com/techlib...l_injector.pdf
here’s a good link to learn about injector frame (dimension) differences
https://www.ictbillet.com/swap-guide...e.html#cat-567
I use the GEN4 50lb/hr truck injectors (12613412) in my LQ9 with heads, cam and TBSS intake. They fit perfect and are only around $100 a set. You'll need the Multec to EV6 harness adapters. There is good injector data that has been converted from Gen4 to Gen3 in the injector sticky thread HERE on the forums. I attached the tune file below.
Another option would be LS2, they are 33 lb/hr.
