I'm in the process of building a 402 for a mostly street application and have been debating what intake to use and what injector size I'll need. I'm leaning towards the Fast with stock 90mm TB and am probably looking at a near 500 RWHP car. Will 37lb injectors support this much power? Is there much difference in the different manufactures injectors? Thanks,Hal

 

Run through the injector equations, you can find them on the RC Engineering web site. As for the injector type, I found that switching from the pintle to the disc type (to Lucas that RC Engineering flow matched and put their name on) the engine was much crisper and the hot start issues went away. Note this was an L-98.

For my C5, I am considering new injectors when I install heads in the spring, I am looking at the Racetronix since they are disc injectors.

 

I have 36lb FAST injectors in my 427. I also have a NIB set of Accel 36lb injectors that I paid over $400.00 for. I will ship to your door for $300.00. They should be cool! Let me know.

 

FAST do not make injectors???
They are probably Bosch or Delphi.
Do your homework on the Accel injectors first before you consider buying them.

Heads up... Delphi had a price increase on their Multec 1 / RP injectors recently. According to Delphi their disc injectors will have a small price increase in Feb '06. Jan would be a good time to buy to save a few $.

 

Just what kind of injectors do you recommend, or should I ask???

 

Delphi, Bosch and Siemens all make good injectors.
Give Thunder Racing a call and they will be able to make an injector recommendation based on your build of motor.

http://www.thunderracing.com/

 

I do not profess to know all.... However, I am somewhat intelligent on many things mechanically oriented. I will be first to admit that injector type (Disc, pintle, etc.), are not my strength when it comes to all things cars. That said, I DO find it hard to believe that a company such as Accel, and the very good reputation they enjoy (Albeit, in ignition components), is suddenly dumping junk on the car guy world. I believe that Holley now owns them, along with Mr. Gasket, NOS, and others. If there is any problem with their product, I am sure they would be most receptive to making things right with anyone who purchased their merchandise. The company for which I have worked for as a Journeyman tool and die maker for the last 30 years is a large customer of Siemens, so I am familiar with their products, and the wholesale prices that I am priveleged to enjoy. I chose Accels for numerous reasons, and price was at the bottom of the list, as the wholesale price of Siemens was/is more than competitive with anything Accel has to offer. Perhaps you could enlighten us all with any/all reasons that we should avoid any Accel injector products. I am front and center when you deem it timely to discuss all things negative about their injectors. This is stated without any sarcasm meant or implied. I have also heard this "rumor" from other automotive experts, so you are obviously not alone when you are, shall we say, reserved, in your endorsement of their injectors. Truthfully, I am running the FAST injectors (You are correct in your belief that VERY FEW injector manufacturers are in existence, and I cannot say with any certainty WHO manufactures them for FAST) because I was "convinced" by a well known sponsor on this forum that they were, in their words, "rebuilt injectors, and not re-manufactured to very good standards/tolerances. At that point in time, we could not get your vehicle to idle at a consistant and/or smooth idle, and after replacing with the FAST injectors, the "problem" disappeared"! Does anyone have any idea why a company with such a good rep. would, astonishingly, throw their hard earned reputation out the window, and assume we all were idiots and sell us a bunch of junk? I think there is a lot more to this story than most of us know, or want to know. I would NEVER knowingly sell any forum member, or non member for that matter, any product which I knew for a fact was not good or up to my standards. And I have no reputation on the scale of Accel's to protect/uphold, other than my self pride/esteem. Please advise, as I am sure I am not the only guy on this forum that is interested. I fully intend to use these injectors on my original motor that came out of my C5, as I pulled it and kept it when I put the 427 in. It was/is a totally stock LS1 that ran a best of 12.50@114mph with no more than a set of shorty headers and Flowmasters and a few bolt ons, and there was no underdrive pulleys on the motor. This was on a convertible with an A4 and a 3.15 gear out back, albeit with a LS1 Edit tune. I am planning on finding a nice used F-body or older Vette to drop it in and it won't stay stock either, so these injectors are part of the plan, unless sold. I remain

 

I put Ford "greentop" injectors on my 427. Don't remember the rating of the greentops, but they are more than I had 37# injectors for 485 RWHP on the SC LS6 I took out, and they were right at maxed out according to my tuner's diagnostics at 485 RWHP.

the greentops are now nearly maxed out with the 427 SC'd, running up at 600+, but they took it anywhere into the 500s.

 

Harold,

Here is an easy to use formula for calculating the size of injector you should use:

Crankshaft Horspower divided by Number of Cylinders divided by 2 divided by .80.

In your case, if you have 500 RWHP and a manual transmission, you have approximately 589 Crankshaft Horsepower (500 divided by .85).

So for you the formula would be:

589 divided by 8 divided by 2 divided by .8 = 46 lbs

I don' t know anyone who makes a 46 lb injector, so I would recommend that you purchase and install a set of 48 lb injectors.

.

 

Thanks Jim, that looks like what I'm looking for-nice and simple. I'll keep my eyes out for something in that range.
Hal

 

42's will put you where you want to be and give you a littel room to grow should you need it.

 

42's will work fine...

 

Accel does not manufacture their injectors. They contract a company to make injectors for them. Early on Accel injectors did have some problems which some of our customers experienced first hand. There is a lot riding on the vintage of an Accel injector. According to Accel these problems have been solved. It would appear that Accel has recently changed the body style and design of their injectors. Mr. Gasket / Accel do make excellent products and that is why Racetronix chose to be an Accel EMIC dealer.

Used injectors should be checked regardless of the type, use or miles on them. There is no way to tell if the injector has been contaminated, dropped or stored without being properly flushed, lubricated, capped and bagged to prevent corrosion. Even the simplest oversight by an honest seller could mean problems for the buyer ranging from bad idle to engine damage. Racetronix supports a steady stream of e-mail from people who have spend much time, money and effort trying to isolate problems caused by faulty used injectors.

No matter which way you slice it used injectors are a crapshoot without being tested. It is no different buying and assembling a used block assuming all the clearances are OK because the owner said it had low miles and was not abused. Most HP car owners are passionate about their cars, take care of their parts and would never intentionally sell bad injectors. For the buyer it would be best to factor the cost of servicing the injectors into the purchase price. This means ultrasonically cleaning, back-flushing and flowing the injectors to check for proper flow, spray-patterns, leakdown and coil impedance / waveforms. In some cases new filters, pintle caps and o-rings should be installed. Some service shops use the term 'rebuilt injectors' which is somewhat of a misnomer as most top-fed injectors can not be taken apart to service their internal components. If the injector has a high cycle-life its internal spring will weaken, moving parts and sealing surfaces will wear which obviously impact its performance.

 

Delphi 42's and Bosch/SVO 42's are the most common injectors you may want to consider. Going with a known injector can sometimes save you time tuning your motor. This is why we recommend contacting a dealer such as Thunder Racing who uses these injectors on regular basis and can provide support tuning them for your build of motor.

 

I am aware that Accel doesn't make their own injectors, as I said there are VERY few manufacturers. My point, though, is that their name IS ON the product, and with THEIR reputation at stake, they should be good, and I felt, and said, that they would take care of their customers. We agree on that. My injectors are less than 90 days old (when purchased), but could be NOS. They have less than 30 minutes running time. I have a hard time believing they are damaged/clogged/worn, etc. You COULD be correct in saying they may be early manufacture dated, or numbered. This, I don't know. Seeing as how you are a dealer, perhaps you could enlighten us of how to decode the manufacture date, serial numbers, etc, if possible. If my injectors are of the later released/manufactured series, they are a hell of a deal for someone at the price I am asking. Would you care to enlighten us of your knowledge on "tracing" the numbers, dates, if any, if possible? All help would be appreciated by me and, I am sure, my potential customer/s. Thank you.