Which injectors?
Thread Starter
|
Road Warrior
Joined: May 2010
Posts: 1,718
Likes: 15
From: Bay area, CA
The 5.3's (HPI-LMINJ-1) is the only injector that is a straight fit on their website. They are a bit longer and have the EV-6 plug that you bike has stock. To use the yellow band 6.2's you will need a different fuel rail or extensions and EV1 to EV6 adaptors. If Jimmy doesn't have what you are looking for. I would suggest some 5.7's matched from five-O.
There is a tolerance with injectors. Matching them means you flow a bunch and match up two that flow close to the same. It's nice to have because they have been flowed and will do what they say, but we can tune both cylinders separately so.....
A bigger injector isn't going to make anymore power than a smaller injector if the smaller injector can supply enough fuel. It's really about what an injector can support. So much HP is going to need a certain amount of air and fuel. Bigger injectors can support more HP because they can pass more fuel for the time aloud. Basically you have 20ms to spray fuel at 6000rpm. So the injector doesn't stay on full time and to obey the law of 80%. That gives us 18ms to spray fuel. A bigger injector will spray more fuel in this allotted time over a smaller injector. Pretty simple.
There is a tolerance with injectors. Matching them means you flow a bunch and match up two that flow close to the same. It's nice to have because they have been flowed and will do what they say, but we can tune both cylinders separately so.....
A bigger injector isn't going to make anymore power than a smaller injector if the smaller injector can supply enough fuel. It's really about what an injector can support. So much HP is going to need a certain amount of air and fuel. Bigger injectors can support more HP because they can pass more fuel for the time aloud. Basically you have 20ms to spray fuel at 6000rpm. So the injector doesn't stay on full time and to obey the law of 80%. That gives us 18ms to spray fuel. A bigger injector will spray more fuel in this allotted time over a smaller injector. Pretty simple.
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
Likes: 132
From: SoCal
Making 135hp with 5.3's on my 107" For a street driven bagger that is close to the edge. Close to the edge with fuel availability and heat issues. Can more hp be made, of course it can! But I feel things will start being less fun once I try to make more. Think the 5.3's will be fine.
Thread Starter
|
Road Warrior
Joined: May 2010
Posts: 1,718
Likes: 15
From: Bay area, CA
Making 135hp with 5.3's on my 107" For a street driven bagger that is close to the edge. Close to the edge with fuel availability and heat issues. Can more hp be made, of course it can! But I feel things will start being less fun once I try to make more. Think the 5.3's will be fine.
Sponsor
Joined: Dec 2007
Posts: 12,084
Likes: 829
Would going to a bigger injector increase the hp at all or just leave you room to make more power.. Does that make sense? I'm waiting on HPI to call me back and see what they recommend, their website says 6.2s recommended for 120hp+ But it seems 5.3 will fit the bill. I dunno if rather go with the bigger injectors if im buying them anyway, just don't want to use the wrong one if it can't be adjusted at the tune
He did tell me that it was unsafe at wot and recommended using bigger injectors. I've kept that in my mind while riding and don't stay at wot for long because of that. What size would you recommend Scott?
He did tell me that it was unsafe at wot and recommended using bigger injectors. I've kept that in my mind while riding and don't stay at wot for long because of that. What size would you recommend Scott?
Scott
Thread Starter
|
Road Warrior
Joined: May 2010
Posts: 1,718
Likes: 15
From: Bay area, CA
As far as my current injectors compared to the bigger ones? No there won't be, I'm going to a bigger injector because my current ones are at 95% duty cycle at wot. If the new pipe makes more power, the current injectors might not be able to keep up and cause a lean condition at high rpms. So I'm not doing it for more power I'm doing it to keep the motor safe. I should have used 5.3s from the get go but I got the 4.9s really cheap
Thread
Thread Starter
Forum
Replies
Last Post
