3800 injector swap ?

Schendel76 · 06-05-2014, 12:16 AM

Heard through the grapevine that 3800 injectors can be used on 3400 and 3100 engines to improve performance and increase gas mileage? Is this true or even possible? Would it make much of a difference on a stock setup? Haven't looked into it too much yet. Figured I would ask on here first.

All input is greatly appreciated, Thanks

Schendel76 · 06-05-2014, 12:26 AM

So right after posting this I got really curious and started researching if the injectors would even fit...so I went on rock auto and looked at ac delco part numbers and pictures for a 3400 injector a 3800 injector and a 3800 supercharged injector...they all basically look the same but have different part numbers...super curious to see what you guys have to say..was out at the local salvage yard today pulling grand am gt mirrors and ran across a supercharged 3800 that looks to be unmolested...

Shiwnath · 06-05-2014, 12:41 AM

Don't even bother. The stock 3400s aren't even close to maxing out the stock injectors. You'd need to tune for them and get the right harness if your car is a 2000+ model. Upgrading injectors wont increase performance or fuel economy. You should only upgrade injectors when you increase airflow of your engine to point that the stock injectors can't keep up.

sleepyalero · 06-05-2014, 12:43 AM

On the money ^

Schendel76 · 06-05-2014, 01:05 AM

Makes sense....some guy swore up and down that it improved performance and gas mileage on his 3100. Had me skeptical..that's why I asked before I started throwing injectors at something that didn't need it. Thank you!

sleepyalero · 06-05-2014, 01:33 AM

Its called a placebo mod. (Atleast I think thats the word)

Basically, the guy went at it most likely not knowing much on performance. Installed injectors. Test drove the car and he THINKS he got more power out of it. When really he didnt. If he wanted to really see if it did, he would have to dyno it.

But yeah. Dont worry about injectors until you do some major modding. Im still running stock injectors with a good tune, and basically full bolt ons. Still arent maxing out yet.

Schendel76 · 06-05-2014, 01:49 AM

Haha. Sounds about right...he probably installed a cold air intake on it at the same time and it made that "wooshing" noise when he floored it..so then he thought he was making major gains and hauling a$$ lol. I was thinking that even if they did fit that it would throw fuel trims off and cause more problems.

aleros_eat_rice · 06-05-2014, 03:36 AM

Higher flowing injectors (36lb/hr for instance) on a stock 3400 will last longer. Because they are rated for more fuel, they run at a lower duty cycle. But like the others say, you don't NEED to upgrade the injectors until you start increasing air flow to the point the injectors can't keep up.

Shiwnath · 06-06-2014, 10:22 AM

Quote:

Originally Posted by Schendel76

Haha. Sounds about right...he probably installed a cold air intake on it at the same time and it made that "wooshing" noise when he floored it..so then he thought he was making major gains and hauling a$$ lol. I was thinking that even if they did fit that it would throw fuel trims off and cause more problems.

So did this guy tune for bigger injectors or did he just put them in? Sounds like he has no idea what he's doing.

MMGT1 · 06-11-2014, 01:31 PM

Also it's quite possible his stock injectors needed a good cleaning. Replacing dirty injectors would certainly increase performance and mileage, but an expensive way to fix something that just needed a service done!