Hi all. So this past summer I have accomplished a lot with my car. I pulled the engine and trans out, fixed a lot of wiring and grounds, replaced all gaskets and seals, new sensors including a heated o2 sensor (car didnt come with an o2 for some reason wire was cut so welded bung in collector pipe below header), msd, brass freeze plugs, oil pump, screen and brace, bigger radiator and fans, adjustable holley fuel regulator, centerforce clutch, there's more but i can't remember. Anyways, I bought the car last year, when I bought it it came with headers, motorvation computer chip, a crane cam that lopes pretty good, and yellow top accel injectors. Car runs fine.... but would like to replace the injectors. They looked fairly bad when I took them out. My issues are this.... I don't know what size injectors they are, I don't know the size cam. What size injectors do I replace these with? How do I find out what accel ones I have? Its a 86 trans am, with a 350 TPI that was swapped in a long time ago from the looks of everything when I took it all apart and put together. I'm looking into getting injectors like bosch 3s or something better as I heard a lot of bad about accels. Thank you.

 

Reach out to SouthBay Fuel Injectiors (They sponsor this part of the forum). I'm sure they can steer you in the right direction.

 

There should be a part number embossed on the Accel injectors. But I wouldn't let their appearance dictate whether they're believed to be good or not. If you're saying the car runs fine, I wouldn't suspect your injectors are bad.

As for new injectors, be careful. Bosch-III's have a reputation for needing tuning in order to run right. Seems to be mixed bag of folks who put them on... some say it ran just fine. Others (me being one of them) find it runs like crap until you tune for them. However, once tuned for they're awesome (I love mine). There are some threads discussing the subject.

From what I understand though, there seems to be a consensus that Delphi's are a true factory replacement such that they don't need tuning, though they're evidently a little more expensive.

Based on your description of the engine, my suspicion is somewhere around 24lb/hr would work fine.

 

Delphi's. The Bosch III's will require tuning and they are very loud.

GD

 

I do get some clicking on mine, yeah.

 

Thank you for the replies. I messaged southbay on their site yesterday, still waiting for response. I'll have to check out the accels that I have again and check for numbers or something. If the bosch llls are like that then I'll find another brand like mentioned above. I'm just curious about what I have already because I don't know if they threw in 21lbs, 22lbs, 24lbs, 26lbs, etc.

 

When I switched to the FIRST manifold I had it machined for LS injectors. Best idea ever.

The IROC I just did a Blueprint engine in got 36lb Holley's. Also work well and quiet. Very similar to stock and came with all necessary data.

I honestly wouldn't do another Bosch III set. No data on them and they are nasty loud things. There's so much better out there with data that it's not worth scraping the bottom of the barrel on pricing to deal with them.

GD

 

Well, i guess you just have to be judicious in which ones you select. If you don't do your homework ahead of time you can definitely get yourself in trouble. Some have data and some don't. On mine, I looked for which ones had Bosch factory data first and then went out to find those exact part numbers.

Like I've said before, I've been on the screwed side of Bosch-III injectors with no data before I learned about the issues. Ran like $h!t and was literally un-tunable. After getting injectors with factory Bosch data and putting it all in, I knew immediately upon startup and letting it idle that it was correct (didn't even have to drive it before coming to that conclusion). But driving it only confirmed that belief.

That said, what I'm seeing happen here a lot of times is people go out and buy injectors and car doesn't run right... Then they post up here only to find out after the fact that their injectors are likely the culprit; and to top it off there's no data on what they bought (which is essentially what happened to me!)

So if there's no intent to tune, then I totally agree its worth the added cost to go for some more expensive ones that are true drop in replacements. The original poster here is doing it correctly... getting the info before making his decision.

Hmmm... there must also be differences on noise. While I do hear some minor amount of clicking, it's not anywhere near what you're describing. I certainly don't hear it with the hood closed.

 

I could hear it in drive-through's with the hood down. Bouncing off the wall of the building. I don't have the insulating mat on my hood either though.....

The problem I see with the whole data thing is that you can certainly find some data for Bosch III's of certain part numbers. And I took the time to derive some data on the one's I had - but most don't have this capability or our level of persistence. The problem I see is that you don't really know how accurate the data is, and then you are getting data off the internet that wasn't supplied IN THE BOX with the injectors. So there's no expectation on the part of the seller that you need this and that it needs to be accurate. Thus if it's not - you are SOL because you received what you paid for as far as the seller is concerned. Now I know that SouthBay would definitely exchange them as they are really good people and their customer service is awesome..... but it would still be a huge waste of time.

Also the data used for the Bosch III's - particularly in the low PW non-linear area - does not lend itself to absolutely correct use on the stock ECM's of this era. The stock ECM doesn't have the capability to accurately compensate for their non-linear nature at really low PW's. Usually not a problem in practice though.

GD

 

Yep. You've certainly delved into it further than I have.