Fuel Injectors

[dustpusher]

Has anyone here purchased the bocsh injectors from fiveomotorsports?They claim that a 19lb injector from a 96to03 4.6 ford is the correct injector for our cars.They claim that ford runs a different pressure and when you put them into our cars they are 22lb injectors.Has anyone run these and were you happy with the results?I just dont want to get the wrong injector.Thanks for any and all of your replys. Dave

 

[Hib Halverson]

One problem with this thread is that you don't state what year Corvette you have.

In a general sense, the Bosch injectors sold by Ford Motorsports, compared to the OE Delcos, are an obsolete design. Ford has very-effectively marketed these injectors as being something special, but they are not.

Lastly, there is no need for anything other than a "stock sized" injector on any port fuel injected Corvette engine that is stock or even one with modest modifications.

The only time you need "bigger" injectors is when the level of modification is such that the engine's required fuel flow exceeds the rating of the existing injector.

 

[dustpusher]

I have a 88.It says I need 22lb injectors.I dont get how a 19lb injector becomes a 22lb.

 

[Hib Halverson]

I have a 88.It says I need 22lb injectors.I dont get how a 19lb injector becomes a 22lb.

What says you need 22 lb injectors?

 

[dustpusher]

I thought that was the stock injector for a l98.

 

[TedC]

Dustpusher, 22 lb fuel injectors are the correct size for the L98. You might want to spend the extra money and have them flow tested to validate balanced flow across all eight injectors. I would stick with the stock rated injectors.

 

[KANE]

Has anyone here purchased the bocsh injectors from fiveomotorsports?They claim that a 19lb injector from a 96to03 4.6 ford is the correct injector for our cars.They claim that ford runs a different pressure and when you put them into our cars they are 22lb injectors.Has anyone run these and were you happy with the results?I just dont want to get the wrong injector.Thanks for any and all of your replys. Dave

$250 for eight NEW Venom injectors from Jeg's. They come in 19, 22, and 24lb varieties.

I've been happy with them and they've been in my TPI for about 4 months.

 

[topless82vette]

My friend took his 1990 to a mechanic and the guy stuck 19lb bosch replacements in the car. Car surges like hell when to low in RPM and under a load .... His 90 calls for 24lb injectors so we'll see if that gets rid of the problem, but don't stick the 19lb'ers in your car or you'll be sorry ....

 

[Hib Halverson]

90s do not call for "24lb" injectors. The OE injector for MY90 w the L98 engine is PN 17112285 which should be stamped 17086544. That is a 22.4 lb/hr injector.

 

[topless82vette]

17086544 .......... 23.9lb @ 45psi 89 350 TPI ...... I've heard L-98's in f-bodies got 22lb per hr. but only have heard vettes got 24lb

 

[TedC]

Well, let me confuse matters a little more. It was my understanding all L98s use 22 lb injectors (corvette, impala, f-bodies) which came right out of a Bosch replacement guide. According to Richard Newton's 101 projects for C4s, "The 5.7 liter injector is sized to deliver 4.83 milligrams of fuel with a 2.5 millisecond pulse, or 23.92 pounds per hour at 43.5 psi".

 

[Hib Halverson]

All I can say is that the data I have says PN 17086544 is a 22.45 lb/hr injector at 43.5 psi. Obviously, at a higher pressure it will flow more and at a lower pressure it will flow less.

Bottom line: unless the engine is significantly modified, put stock injectors in it.

Use of an injector of less flow capacity (ie: 19s instead of 22s) will have the motor lean at WOT. Use of an inector of more flow capacity (ie 24s instead of 22s0 will have the motor rich at WOT. Additionally, during closed loop, an improperly size injector will cause the ECM to skew injector duty cycle or pusle width to compensate. If the injector's sizing is improper enough, the ECM can run out of the ability to skew the mixture and, once the ECM runs like that for a while, it will turn on the check engine light.

Now, to a certain extent this lean or rich issue can be mitigated by recalibration but...there are limits to how much you can compensate for improperly-size injectors with calibration.

 

[-=Jeff=-]

injector sizes vs years:

85 L98= 24lb
86-91 L98= 22lb
92-93 LT1= 22lb
94-96 LT1= 24lb
96 LT4= 26lb

90-95 LT5 I believe are 22lb as well

 

[pkincy]

All I can say is that the data I have says PN 17086544 is a 22.45 lb/hr injector at 43.5 psi. Obviously, at a higher pressure it will flow more and at a lower pressure it will flow less.

And the Ford injectors are normally rated at less than 3 bar. I don't have the individual rating specs in this computer but Ford tends to run their older fuel rails at 33-39 psi. Hence a 19 lb/hr Ford rated injector will flow more than 19 lb/hr in our 3 bar fuel rails. Who knows it may even be 22 lbs/hr.

The early SVOs were rated at 30 lb/hr of flow at 39 psi and I have used an injector constant of 32 or a bit above in my PCMs (93 Y and F bods) using these injectors.

I would expect that the Ford replacements might work but unless I knew the pressure for the flow rating or had them tested at 3 bar I wouldn't vary from the stockers. It is not worth the tuning hassle unless you have the equipment, wide band sensor and knowledge to make certain you are doing the right thing.

Try this if you want to wade through it:

http://users.erols.com/srweiss/tableifc.htm


Perry