hmx

I need to replace my fuel injectors and was wondering if anyone had good or bad experiences with some of the sellers out there. In particular, I'm looking at getting my injectors as remanufactured parts (with warranty) from:

www.injectorwhse.com

If anyone has experience with them, I'd be interested to hear it. I'm also assuming that remanufactured injectors are fine and that I don't need to break my wallet on new ones.

Thanks!

hmx

Another question: Is it a big deal to have 'matched' TBI fuel injectors? I.e., the exact same flow rate? Or are the tolerances on those off the shelf so close that it doesn't matter? I'm asking because I've seen some stuff advertised as if it's a big deal to have the fuel injectors matched.

last_

not to in the know.. but enough to know without a shadow of a doubt that you want the flow rates of both exactly, or as close to exact, as possible.

Ronny

iTrader: (1)

look at Ficht Fuel Injectors

Johnny Blaze

iTrader: (15)

Any suggestions where to look for these.

Goggled and came up with a bunch of tech about boats.

dimented24x7

iTrader: (2)

The injectors are still in production by GM/Delphi if you want to get the original units. They're more than the reman. units you may get, but they're likely of better quality. I have used the new BWD units, and had no issues. They're not too expensive and are available thru a lot of the autoparts stores if you want new units for less.

Just out of curiosity, whats wrong with the current ones? TBI injectors are very robust, and seldom fail, and almost never clog. They're not like some MPFI injectors with micrometer sized orifaces that plug up real easy.

Ronny

iTrader: (1)

FIC fuel Injectors. I am a boat guy and was confused. www.fuelinjectorclinic.com

hmx

Nothing's wrong with my current injectors, except they are the wrong size. I swapped out my 305 for my 350, and retained my original fuel injectors. Now I have a bit of a power sag before I go into closed loop, and pinging on the highway at higher speeds. I had originally thought I needed different injectors, but for the '89 Caprice, GM did not list it with a 5.7L V8 in it, and thus I had no part #s to compare. I left the stock 305 injectors in there, and, after discussing my datalogs (in the DIY PROM boards) it looks like the injectors I have are too small. Thus, I will likely have a nice set of 350 injectors sitting around after I'm done.

MiScHiEf

http://www.turbocity.com/default.php?cPath=16_30

Here ya go, not the cheapest but has some information as well on the page.

dctrumpet

iTrader: (10)

depending on your horsepower goals your 305 (5235279) injectors are sufficient if you increase your fuel pressure. Remember in 1994-1995 GM put 45lb injectors in their 7.4L TBI GM trucks, but ran them at 30psi.

Everyone tends to focus so heavily on having a certain casting number instead of focusing on matching fuel pressure/flow with their current/projected horsepower.

First, you need to have a set of injectors that have been flow-tested and matched. For example, once you know that your injectors flow at "750cc/min" at 1bar (14.7psi) then you can figure out that your injectors will flow "x" amount at "X" amount of pressure thus, being able to support a certain amount of horsepower.

This is where you need to be good at tuning your chip or having someone like Brian Harris assist you.

If you have a basic 350 with basic mods then the fuel requirements are not major so a "basic" set of 55lb 5.7L (5235206) injectors can be sufficient, but..... You never know what the flow rates are unless someone sells you a set with a detailed flow sheet.

For example: I have 18 sets of matched 5235206 55lb injectors. Their flow rates are SO DIFFERENT between each matched set. The lowest flowing set i have is 650cc/min @ 14.7psi and the highest flowing set is 800cc/min @ 14.7psi. Yes, that's GM for you and Yes they are the same casting number. Makes no sense so Yes it is important to have matched sets. So, the 650cc/min can only support a much lower hp motor compared to the 800cc/min set. A hundred hp difference in their capabilities. VAST difference.

DO NOT BUY INJECTORS WITHOUT A FLOW SHEET PROVING THEIR FLOW RATES.

I hope this helps. I have had over 200 sets of injectors cleaned/flow-tested and have a great understanding of them. GM TBI injectors are the most inconsistent in flow-rates. It can literally take 30 injectors (15sets) of the same casting number to get 8-10 matched or close to being matched sets. It's frustrating to say the least.

Matched sets will ease your tuning nightmares, LOL!!!!

Good luck!

dctrumpet

iTrader: (10)

ALL my injectors are sent to Gordon at WitchHunter or Injector-Rehab. More recently all go to Gordon.

Injectors4u, Injectorwhse, Turbo-City, etc etc etc are all EXCELLENT businesses with great reputations and great guys to work with. PLEASE if you purchase through them or anyone else MAKE them give you a flow sheet on the EXACT injectors you are buying from them. Make sure the injectors are engraved/marked and the reports/sheets are marked with the exact numbers as on the injectors.

hmx

This is EXACTLY what I was looking for and a great help! Thanks so much!

dctrumpet

iTrader: (10)

To be completely honest with you this is how everyone should be with regards to TBI injectors. Unless someone is planning on supporting 375-400hp then focusing on casting numbers is NOT as crucial if you have the capability of tuning your chip and adjusting fuel pressure.

Again, 90lb 5235231 injectors can flow from 820cc/min to 990cc/min (yes, i said 820-990 lol). Another vast difference in ranges. So, YOU CAN'T assume that all 5235231 TBI injectors will support a certain hp range. That is why it is so VITAL to know exactly what your injectors are flowing at a given psi. 1bar (14.7psi) is the best way to get a base reading of flow-rate. For serious performance minded people I recommend that they have their injectors tested at 1bar and 2bar (29psi). This will then give you more confidence in knowing what a certain pair of injectors are capable of handling.

Does this information help? My 5235231 injectors are flow-tested at 14.7 and 29psi.

Good luck and please know what you are buying!!!!!!!!

dctrumpet

iTrader: (10)

I helped a friend with his project. He has a 370hp 5.7L TBI. He is running 17084327 (Cop Car) injectors at 26psi. We knew what the flow rates were at 14.7 and 29psi and this set happened to flow closer to 80lb 17084304 injectors.

Got to love GM!!!! No rhyme or reason to the TBI injector, lol!!!!

hmx

Just wanted to update everyone: I replaced the fuel injectors on my car with some I bought from dctrumpet, and the car runs like it's new. My original 305 injectors were just not cutting it for the 350 at the pressure that I'm running, and there is no problem at idle now, and no power sag on the road. Everything is smooth and quiet. Thanks to ronnie, dctrumpet, and everyone else on the boards who helped out. My next step is going to be playing around with the chip to see what I can get out of the engine.

dctrumpet

iTrader: (10)

Hey! I am glad things worked out for you. It helps to have flow-matched injectors doesn't it? Keep in touch. If you need anything else please let me know.

Sean

hmx

Will do! Thanks again!