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Bigger injectors=new tune?

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Old Sep 23, 2016 | 12:38 PM
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Default Bigger injectors=new tune?

I believe I'm at the max or over the amount my 5.3 injectors can handle, and I'm bored.

So I have a new set of SE 6.2 injectors on the shelf, just wondering if I can slap them in and the target tune module will auto tune to compensate for the bigger flow or if I need to request a new tune from Fuel Moto?

I'm thinking of going to a 124 upgrade kit this winter and want to get into the 140 range, so the bigger injectors are just in preparation of things to come.

New tune or just install and run them?
 
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Old Sep 23, 2016 | 01:14 PM
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Unless you are running full throttle 100% of the time through all the gears, it is very unlikely you are maxing out the 5.3 injectors.

You will need a new map if you change the injectors due to the difference in flow rates.
 
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Old Sep 23, 2016 | 01:28 PM
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I am also not sure you are near the limit of what the 5.3's can do.
 
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Old Sep 23, 2016 | 01:30 PM
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Running 5.3's in mine. Work just fine.
 
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Old Sep 23, 2016 | 02:03 PM
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I put in 160hp desired at 85% duty and 55lb fuel pressure and it comes up 42lb which is 5.3grams/sec. So I think the 5.3's will be fine
 
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Old Sep 23, 2016 | 02:23 PM
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Same for me, I was running the stock 120R injectors in my Procharged setup with 218hp to the tire.


I only had to upgrade my injectors and fuel pump for my current setup @242hp.
 
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Old Sep 23, 2016 | 02:41 PM
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Originally Posted by ramx50
Same for me, I was running the stock 120R injectors in my Procharged setup with 218hp to the tire.


I only had to upgrade my injectors and fuel pump for my current setup @242hp.

What are the 120R stock injector size?
 
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Old Sep 23, 2016 | 03:05 PM
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Originally Posted by hrdtail78
What are the 120R stock injector size?

5.3
grams/second in a 58mm throttle body.
 
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Old Sep 23, 2016 | 03:22 PM
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Originally Posted by hrdtail78
What are the 120R stock injector size?
The 120R doesn't include injectors or throttle body, so when you buy the engine you also have to pick up those items.

I've always read the 5.3 were only good for the 120 hp range, and after that you were over working them.

Like I said I was bored and ordering stuff anyways and just added these to the cart as well, maybe I'll install them at the same time I do the 124 upgrade and only have to worry about getting one new map.

Thanks for the replies.
 
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Old Sep 23, 2016 | 03:26 PM
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Originally Posted by hd_rolling
The 120R doesn't include injectors or throttle body, so when you buy the engine you also have to pick up those items.

I've always read the 5.3 were only good for the 120 hp range, and after that you were over working them.

Like I said I was bored and ordering stuff anyways and just added these to the cart as well, maybe I'll install them at the same time I do the 124 upgrade and only have to worry about getting one new map.

Thanks for the replies.
Whom ever wrote that 5.3's were only good for 120hp was incorrect for whatever reason. I'm using 5.3's and I'm way past 120hp. 5.3's are good to at least 160hp@55psi and at 85% duty cycle.
 
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