This is why I hate buying Pre-modded cars

[4n_eatr]

Ok so you can look at my sig and see some work has been done to my car. Unfortunately I didn't do any if it except some minor things. Right now I'm just doing damage control. I've been having an issue with a rattle at 2000-3000 RPM under part throttle, not really noticeable at full. So I start checking all the exterior crap, find the BBK CAI is rattling on the valve cover, didnt fix it... Found the pass radiator mount loose, didnt fix it. Then I noticed the Fuel injectors are yellow, which means they're 19#! Found a calculator online that says I need at least 30#. How much damage am I doing by driving it?

[Mista Bone]

Have you pulled the plugs to see if it is running lean? How is the car/MAF tuned?

125 shot ZEX dry kit, I went to Ford Red Tops on a 93 cube Honda which came with 240cc/min stock.

That might be a death rattle, compression/leak down check is needed.

http://i107.photobucket.com/albums/m307/bonespec/Honda/D16Z6/N2O%20tuneup/ford30_4.jpg

[4n_eatr]

I'm really hoping its not piston slap. Every other car I've heard of that has the pistons/rods go bad have rattled All the time, not just under load. I'm pulling the plugs tomorrow and replacing them anyway. I don't know how it's tuned exactly. I'm planning on taking it to Dayton 5.0 after I get my injectors to have it re-tuned.

[facemelter71]

Has it been tuned? If so,who was the tuner.

And 19 pound injectors. Take those out.

[4n_eatr]

It was tuned in Columbus by some import shop (judging by the name). I think they just reflashed the computer. I have 34# on the way anyway so hopefully that will take care of it after I get a tune.

[cstreu1026]

I ran out of injector around 300 RWHP. I would guess you are in that same ballpark NA.

[4n_eatr]

That's where I am exactly, lol. 299.8 rwhp to be exact.

[cstreu1026]

It shouldn't be all that lean that low in the RPM range then but a bigger set of injectors would certainly a good investment. Just keep in mind that you are going to need to have the car retuned for the bigger injectors.

[4n_eatr]

Yeah I have that planned already. That's what was curious about this. It's only user part throttle. When I give it hell it's barely noticeable if at all. I'm going to haw someone look at it at Dayton 5.0 and maybe they'll have a better understanding after they hear it in person.

[cstreu1026]

Does it matter if the car is cold or at operating temp?

[4n_eatr]

It's a little worse if its cold, the warmer it gets the more it moves up the RPM range and the quieter it gets. Which made me think at first it might be oil related, (ie pump, tensioners) but it should be making the noise all time.

[cstreu1026]

I have heard piston slap can be much more noticable with aftermarket rebuilds but I think that was more noticable with strokers than standard stroke engines.

[4n_eatr]

But shouldn't piston slap occur all the time, wether you rev up the engine in neutral or in gear?

[cstreu1026]

My understanding is that with after-market forged pistons it occurs with the engine cold because the metal hasn't expanded yet. Its made worse with a stroker because it pulls the pistons further out of the bore allowing them to move around more.

[4n_eatr]

Ahh gotcha. Thanks for the info. Ill have to dig a little deeper and see if there's something I can do to quiet it down for a while.

[Mista Bone]

Hondas with OEM pistons will slap when it is cold out. Forged are even louder until they warm up and expand.

Was the shop Slowmo?

[Mista Bone]

Hondas with OEM pistons will slap when it is cold out. Forged are even louder until they warm up and expand.

Was the shop Slowmo?

[4n_eatr]

Advanced Imports / RX7 Store

[2007ShelbyCobra]

Timing chain tensioner? Mine had a rattle, much more noticeable cold, around 2-2500 rpm. It scared me it was so loud, after I had the cams put in my car it went away. It hit me that it was the tensioners, thats the only part that was changed during the instal and it hasnt done it since. May be something completely different, probably is, but the description is the same as my problem.

[4n_eatr]

Timing chain tensioner? Mine had a rattle, much more noticeable cold, around 2-2500 rpm. It scared me it was so loud, after I had the cams put in my car it went away. It hit me that it was the tensioners, thats the only part that was changed during the instal and it hasnt done it since. May be something completely different, probably is, but the description is the same as my problem.

That was my first thought, but did it happen just under load? I'm pretty good at diagnosing noises, but that's the part that is throwing me for a loop. Anything I can think of that would make this noise, should be always making this noise. I might just have to drive it until I can have Dayton Performance look at it. Or maybe someone at the cruise on Sunday can listen to it and have a better idea. Might be a good excuse to get some bigger cams! Lol

[2007ShelbyCobra]

That was my first thought, but did it happen just under load? I'm pretty good at diagnosing noises, but that's the part that is throwing me for a loop. Anything I can think of that would make this noise, should be always making this noise. I might just have to drive it until I can have Dayton Performance look at it. Or maybe someone at the cruise on Sunday can listen to it and have a better idea. Might be a good excuse to get some bigger cams! Lol

1/4 throttle cold, not really noticeable warm. Id drive it around 2500 or higher rpm where it stopped, until it warmed up. Im talking like first 5 minutes of driving

[4n_eatr]

Ill try that tomorrow, neighborhood might get a little mad at me, lol. It starts at 2100-3000 when it's cold, then slowly moves up the RPM range until its gone. Also, if it is piston slap, could this be because I use synthetic? I think it's used to conventional.

[2007ShelbyCobra]

Ill try that tomorrow, neighborhood might get a little mad at me, lol. It starts at 2100-3000 when it's cold, then slowly moves up the RPM range until its gone. Also, if it is piston slap, could this be because I use synthetic? I think it's used to conventional.

Okay, if its moving up in the rpm range that changes things. Id let Mike take a lot at it, its his job lol