I pulled my primary fuel injectors today and found out both had cracks on the nipples (not sure of the exact name). I think they do need to be replaced but I want to be sure before I spend any money. So do they need to be replaced and how much do they cost?

 

I know this has been up for only three hours but I would to know ASAP so I could order the parts tomorrow.

Thanks

 

Sounds like the pintle caps are cracked. I would not install them as is because the caps can crack further and the pieces can fall into the motor causing harm. I have a bunch of 550s that were freshly rebuilt. Shoot me a pm.

 

Yup, sounds like the pintle caps. You can also send them out to witchhunter or rcengineering to have them cleaned. They also replace the o-rings and pintle caps and it's a really reasonable price. Just takes a few days.

 

You dont even need to caps, they are only there to protect the injector.

The injectors are fine. Have them serviced, shouldnt run you more than $80.

 

The caps help the injector seat in the rail and protect the pintle when they are inserted into the rail. You could run them without the cap, but I wouldn't say they aren't needed.

 

I ordered a rebuilt set from Rotary Experiment Seven. I think I'll have these cleaned and have the pintle caps replaced and then sell them. Can I have these bored out to flow 850cc?

 

Bored out injectors have failed many times on other people and that was 1300 from 850. Email Ray Crowe on 850's you might be surprised on price.

 

Specer328- You purchased 550s from me. While it is possible to enlarge them, you will most likely have idle issues because it will be hard to tune the idle. People generally have the 2ndary 850s enlarged.

The reason why many enlarged injectors fail is because people take an old injector, modify it, and expect it to perform as new. Personally I would rather go with top feed injectors instead of enlarging the stock side feeds. I don't sell enlarged injectors normally nor recommend them.

 

I guess I won't be enlarging them then. I was going to enlarge the old primary injectors (not the new ones since I really just want to fix my car right now) for the future when I would need more fuel but I'll just get 850s and a modified primary rail. Thanks for the advice and help (especially Rotary Experiment Seven).