aklim

I'm more worried about whether it can hold up to ethanol or not. As to why you would get new, well, it depends on whether you are willing to spend more to be sure it is 100% new or not. If you tell me it is a junkyard one, I agree. OTOH, if it is tested and cleaned, I have no issue. I'd ask Jon about this since he plays with it all day long for a living and see what he recommends. At that point, someone might chime in and explain why it is or is not a good option.

RedHot85Vette

I've learned that Jon is the injector guy to speak to. I'm going to eventually seek his wisdom as recomended. But I' like hearing what users have to say..The experiences of the drivers of these things. That's why I Like this place. It's a Treasure Chest of knowledge and experiences regarding the C4's and Corvettes in general. I'm going to ask sellers about ethanol resistance of their products, and some other questions that I have. Simple stuff.I'm not trying to be over analytical. I'm just very curious and these things are so very important to the performance of these vehicles, regardless of how the cars are driven. You don't want to be stuck on the side of the road, whether your going to the supermarket, or the track.

aklim

I think the original issue was the fuel cools the coils on the Multecs They were fine with no ethanol or additives that could eat away at the insulation Ethanol came along and changed the game.

RedHot85Vette

I like everything you said especially "Ethanol came along and changed the game"... Not only is it right and smart... it sounds cool too! It all triggered something in my head. For curiosity, I'm going to ask some sellers what experiences they're having with the ethanol problem and see what responses I get.

aklim

I believe Bosch 2 and up did not have the issue since it was designed around ethanol but forward their answers here, please.

Dreckerlin

KyleF

Wow...
1st, the fuel pressure has been discussed and an adjustable fuel pressure regulator to set pressure where the injectors are rated has been discussed.
2nd, I understand NOS parts as a purist. Some cars I have owned were treated this way but not for performance related reasons. I don't mean that in regards to maximum hp, I mean that in regards to how it ran/operated. It was a decision to keep it factory correct for value, not for how it drove.
3rd, the second part of that statement is ridiculous. "No other injector will give you the proper factory results as what GM put in it from the factory" After 32 years, you really believe injectors, spark plugs, and other parts today are not better than 30 years ago. I work as an engineer in the automotive world and have worked for OEMs. I understand the production methods, tolerances that were used then and now , and design criteria. As mention, the Multecs don't even support 10% ethanol gas, nor does the old fuel rail o-rings. Non ethanol gas is not always readily available, trust or not.
4th, as seen above in the thread I pointed out the OP needed to do some research and see what all this swap entailed. Others have chimed in as well and you can see everyone agrees one one thing. Once set up properly the new injectors work great.

In the words of president Trump, you are "Wrong". Factory parts are always the result of compromise. Keeping it all stock only provides the driving experience of 30 years ago, not the best experience.

The

aklim

Sure. GM spared no expense in making you the best possible vehicle. That is why they are also called Government Motors. Because the quality was so good. I also have a bridge for sale.

And same was, is and always will be the best? Time stands still? Bridge still for sale.

"You're" not necessarily good to go. It's often inconvenient and/or more expensive.

aklim

Factory parts are the result of the max profit for the company and if you benefit so be it.

BlowerWorks

KyleF

I think we both agree about the original factory part not being the greatest part to use. Though, I disagree about profit. Bad parts have caused warranty claims and recalls... all which hurt the bottom line. Why they use a sub-par parts is because of a series of compromises. One of those is always focused on cost no doubt, but availability, preferred vendors, contracts, geographical location, raw material availability all factor in as well. It is with a target to maximizes profit given a set of constraints.

aklim

Sure. If I have a 3 year warranty, I would get the cheapest part that lasts at least 3 years. If the 5 year warranty one costs more, you can get it yourself. That is my point. Maximum profit.

tdereggi

Redhot85vette, For your car to run well, its incredibly important that your Fuel injectors work consistently, and that your Fuel Air ratio is proper. One of the things I overlooked when I first got my 85 Vette, which added ongoing frustration, was how much it could matter swapping out a fuel component such as to a aftermarket MAF, Generic performance ECM CHIP, or Injector, with out consideration of whether it considered specs of the other components that had changed as well. I can give an example of when I installed a Grenatelli adjustable MAF and a hypertech chip togeather, which was a huge mistake, although individually they performed as represented. Worked great once I put back the stock MAF. (PS. I got to give credit and thanks to Blowerworks for solving that one for me, after about 2 minutes of his help over the phone. He sure knows his stuff). Detecting a Fuel injector with compromised flow and replacing it can be a timely process, considering all the upper intakes, runners, fuel lines and rails, need to be removed first, to swap them. Some represent they c an do it in 3 hours, but It usually takes me a full weekend, atleast 3hrs cussing and swearing just to get the fuel lines connected back on. For that reason, I highly recommend putting in quality parts from a trusted quality vendor, the first time. Dont risk unknown. Going remanufactured is fine, as long as its a reputable vendor that will do it properly. I believe FIC (Fuel Injector Connection) to be one good place, and where I got mine. Personally I beleive seeing is believing. There is a video on FIC's website, that shows the various injectors flowing at various pressure levels. Its amazing to watch the Bosch3 injectors outlast all the others, to much higher pressure levels, and with its perfect spray pattern. That alone is a good testimonial why the Bosch3 is a good choice, and is likely going to perform consistantly longer. The proper 24lb injector (new or used) is usually available from FIC. Yes, they need the double Orings mod, which he provides.

My 85 car ran much better, after I installed the Bosch3 injectors. I suspected two of the previous multi-tec injectors werent flowing properly. I cant tell you for sure if it ran better because, there were no longer bad injectors in car after replacing them, or if it was the Bosch3 performing better than Multi-tech. But the Bosch3 did work well. When you have intake/fuel rails off, its usually also a good time to install an adjustable Fuel Pressure reg, replace fuel line seals, intake gaskets, and clean out the EGR ports.

One note.... a common test is to pressurize the fuel system to spec (36-40 psi) , turn off car, and see how long the pressure holds. Whats supposed to happen is the pressure is supposed to hold for a very long time or very slowly progressively drop down, Atleast several minutes long at significant pressure. (Its reasonable to expect it to hold much longer, the Multi-tecs did). After I installed my Bosch3s, the Fuel system wouldn't hold the pressure long, after turned off, maybe 20-30 seconds tops before it was at half pressure. No visual leaks anywhere. Fuel Pressure meter showed correct pressure while car running. Originally I was concerned about whether the quick pressure drop down test results loss were normal, and if it might be possibly that one of the new injectors was leaking internally. I was insured that it was fine, and wouldnt cause any performance issues. Sure enough car continued to run great.

aklim

Don't forget to do the TB. Take it out, take out the IAC valve and remove the IAC housing and the top plate. Clean all the passages.

Where would it leak to? Either it goes into the intake manifold or back into the tank. Did you crimp off the lines at the pump area to test where it was leaking to?

tdereggi

Good question, but I don't have a good answer. I was performing the work outside in the middle of snow season, so I decided to just accept the repair as it was and call it done, since I couldn't see any negative impact to car's performance. It ran better than ever . I plan to revisit the issue, when I swap up to 30-42lb injectors, needed for my SuperCharger upgrade, occurring shortly.

But... yes, I did attempt to block off the line at the Fuel pump. I did so with a clamp. And I agree, the only two places it could leak hidden would be, into the intake or back to tank through Fuel reg (which I had replaced at same time). Its possible that I didn't fully clamp the line. (I thought I might add a physical valve inline at some point, to make testing more reliable). But I was thinking it was more likely leaking slightly through injector into the intake. Some people were telling me that some injectors will do that, and not to worry about it, as it holds enough pressure long enough that it wont effect car's running performance. My only concern was verifying there wasn't a visual fuel leak that would be a safety issue, but there was not.

gerardvg

Hi
i have bosch 111 24lb injectors in my 85,
the std fuel pressure was around 33psi.

When i replaced the fuel pressure regulator its up to 43psi, however no ill effects she starts quickly and have not noticed the gas mileage change.

Cheers

aklim

Not sure how much more changes it causes but I'd be curious to see how much adjustment the ECM is making to compensate for the increase in pressure and volume