Noisy Injectors

[Mopud]

Hi all,

It's been a while since i've posted here. The stroker has been a mixed bag but largely running well - managed to get 175rwhp out of it with the unichip lately so sure beats the initial output i was getting after it was first built (144hp).

Thought i'd been suffering from noisy lifters but after running a stethoscope over it I've found the injectors are insanely noisy. I believe I could benefit with dropping them anyway as I opted initially for 27# bosch injectors (I really don't know why, I think I was overzealous with my HP estimates). I would really like to now get rid of the highly annoying tapping injector scream and return the engine sound to some level of normality.

Any experiences with this from anyone else? And could I expect more success do you think with the 24# injectors as far as fueling/tuning is concerned? I have almost always had some level of detonation especially at freeway speeds and the unichip tuner shop just couldn't get on top of it, try as they might. I know this is largely timing based and they couldn't see any issues with injectors or fuel but I am just curious.

It's a 2001 40 thou overbore stroker running Comp cams 68-231-4 camshaft.

Regards,

Anthony

[SilverXJ]

Busch 0-280-155-784 or Jeep 53032704AB. Both work out to about ~24psi on the rail. However, if you have a tune for those huge 27 lb injector it will need to be changed for the 24 lb injectors. Also, keep in mind that the 231-4 cam is a bit on the noisy side.

[Mopud]

Great, thanks Chris. I'll find a set - unless I was looking in the wrong area I couldn't find any reference to injectors in the sticky parts and build posts.

Yes I'm aware the cam is a bit noisy. Are there any aftermarket ones now that use the thrust plate design and not the bolt pin and Spring retainer?

[Russ Pottenger]

Jones is grinding Cams based off the late cam utilizing the thrust plate. The downside is nobody makes a double roller for it.

[Cheromaniac]

Jones is grinding Cams based off the late cam utilizing the thrust plate. The downside is nobody makes a double roller for it.

The stock '94+ "silent link" timing chain is pretty robust and the sprockets are beefy so I wouldn't worry about it.

[Mopud]

Yes just checked my injectors, part number 0280155849. I can see they appear to be 24lb/hr on the Fords however I think with the Jeep fuel rail pressure at 49psi they're pumping closer to 27lb/hr. I've just ordered a set of 0280155784.

Thanks a lot

[SilverXJ]

however I think with the Jeep fuel rail pressure at 49psi they're pumping closer to 27lb/hr.

You are correct.