IS 350 TBI compatible with E10?

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mibars

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Hi,
In Poland in upcoming year we can expect that gas stations will switch from E5 to E10 regular gasoline (95 RON octanes), with E5 most likely available only as premium gas (RON 98 octanes) as gas stations will be mandated to sell E10 gasoline.

Is a small block 350 TBI fine with running on E10? I'm checking our government page for checking compatibility, they do not have Suburban/Blazer/C5/K5, but they have a 1989 Camaro with a 5.7 listed as not compatible with E10.

In fuel prices thread I see that several people mentioned E10 prices. So shall I worry about E10? As my hobby car Burb is not making many miles so it sits a lot.
 

dusterdude

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E10 will not hurt your engine,however you may have to richen the jetting a bit and all of the rubber bits in your fuel system will not like it at all.
 

mibars

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I guess that TBI equivalent of jetting the carb is playing with fuel pressure. Anyway that sounds like making the MPG worse :/
 

Redfish

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I have been running E10 in my 1987 TBI with no apparent issues. It probably has some effect on the rubber components of the fuel system but I have not seen that yet. I switch from E10 to pure gasoline depending on availability and honestly cannot tell any difference in performance or fuel mileage.
 

mibars

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Okay, that's good news for me. E10 gas is currently a big topic in Poland and everyone, including me is probably overreacting :) I recall same commotion when they first introduced gas with biocomponents, now known as E5.
However an official page saying that similar engine should not run on E10 was concerning.
 

fast 99

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TBI systems have adjustability built into them but there are limits. They are approx. 20% adjustable for wear, altitude, fuel pressure, or other changes such as fuel type. Provided the ECM is not at any limit drivability should not be affected. The O2 sensor provides data to ECM that is used to adjust fuel trim.

That being said given a choice I would not use it. Ethanol fuel is short lived really horrible stuff. A stabilizer is mandatory. Ethanol will attack rubber parts not designed for it. Be sure tank is full before storage to help slow water absorption and possible corrosion.
 

Hunter79764

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Agreed, ethanol is not great but won't kill it immediately or anything. It will age rubber components quicker, but there isn't a ton of rubber lines on TBI trucks so that helps. E10 and even E15 is very common here, and I have run it in my TBI vehicles consistently for years.
TBI has adjustability in it, but that adjustability is intended to make up for typical worn components like dirty fuel filters, clogged injectors, weak fuel pump, etc. I'd recommend keeping on top of your fuel filter changes, and running some good fuel system cleaner occasionally. I like SeaFoam, others like Techron or Lucas etc., not sure what is available over there. And you might look at your fuel pressure, see if it's weak etc. If you have issues, the 30 year old pump might be due for a planned replacement, especially the submerged piece of fuel line in the tank. It can start seeping, and your first indication is low fuel pressure. Being submerged, it is the first one to degrade most likely, as it has fuel inside AND outside.
 

bucket

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Most Ohio stations have been peddling E10 for 20 years. It sucks for a few reasons, but it's just the way of life now.
 

Catbox

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Our 1995 Sub and its TBI have ingested 1,000's of gallons of the E10.

Seafoam is a good thing for them every once in a while and it will let you know when you need it too.
 

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