Fuel injector hoses 50psi vs 255psi

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camplo
Posts: 125
Joined: Dec 02, 2016 6:38 PM
Location: Bay Area

Fuel injector hoses 50psi vs 255psi

Post by camplo »

I am in the process of replacing my injectors. At the same time I wanted to replace all the old fuel hoses and any vacuum hoses. Do I need to get the more expensive 255psi fuel hoses? I have read the m30 runs around 2.5-3 bar ~43psi. I guess I wouldnt want the hose to run at/near its max rating but I just wanted to ask to be sure.
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Fuel injector hoses 50psi vs 255psi

Post by Mike W. »

Doesn't have to be 255, but 50 is not enough. 50 is not FI rated hose. A bad FPR or blocked return hose can send it over 100PSI. Now you can use it on the return since that's just a couple of PSI at most, but not on the supply. I'd probably want 90-100 minimum.
Blue Shadow
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Joined: Feb 12, 2006 12:00 PM
Location: SE PA

Re: Fuel injector hoses 50psi vs 255psi

Post by Blue Shadow »

30R9 with about 200psi is fuel injection hose.
turbodan
Posts: 9207
Joined: Jan 09, 2007 10:19 PM

Re: Fuel injector hoses 50psi vs 255psi

Post by turbodan »

I just had a fuel line burst a few weeks back. The previous owner had installed some of that 50 psi stuff. It worked for a while, which is why I wasn't in a hurry to replace it. It was on my to do list with numerous other repairs this car needs. One day the car stalled out after I dropped the kids off at the bus stop. The feed line had split about two inches upstream from the fuel rail. It was an inconvenience but at least the car didn't catch on fire. Gasoline is really good at catching on fire, you don't want to dick around with that.

Spend a little more and get the right stuff. It's $10 a foot, you can afford it.

https://www.oreillyauto.com/detail/c/ba ... gaty/27340
camplo
Posts: 125
Joined: Dec 02, 2016 6:38 PM
Location: Bay Area

Re: Fuel injector hoses 50psi vs 255psi

Post by camplo »

I ended up getting the 255 psi rated hose. It was 7.49/ foot from napa and I found a 20% coupon. Ended up getting new injector hose clamps as well. After doing the injectors, replacing the hoses and getting it all back in and installed the car did not start. I triple checked everything and couldnt figure it out. Ended up being I reversed the feed and return lines :laugh:
Mike W.
Posts: 27180
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Fuel injector hoses 50psi vs 255psi

Post by Mike W. »

camplo wrote: Apr 29, 2023 2:41 PM I triple checked everything and couldnt figure it out. Ended up being I reversed the feed and return lines :laugh:
Trust me, you're not the first to have done that.
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