I finally got my IROC!!!!!!! . Drove it home last Saturday. It's a black 350 hardtop. Wicked nice. Unfortunately though I only got to drive it twice, once on the test drive and then home before leaving to visit family, so I'm dying to get back and drive it, wash it, wax it, everything. Needs a couple things (headlight is out, new hood struts, plug an exhaust leak) but nothing major. I can't wait til she's all shined up. Hearing that 350 light off, man its beautiful. I'll post pics once I've got her all shined up, but damn is she nice-looking. Anyway, just sharing my excitement . Peace.

I love that new car feeling.

speaking of new cars, I'm trying to figure out something, my car knocks when I take it over 3000 rpms, and I think this is because of the 87 octane in it right now (dealer filled it up). Would this be the problem, and switching to a higher octane fuel take care of it, or would it be something else? On that note, what octane are you 350 TPI guys running? I'm going to try a quarter tank of midgrade and see if it stops, if not I'll try Premium. Can anyone help me out here?

TPI is 9.3 compression so it shouldn't need 92 octane, and TPI also had knock sensor so it shouldn't knock there either. The only thing I can think of is the electric dist may be a little broke and the dealer mechanic adjusted it so it would idle and drive under light throttle. That's being optomistic. It could always be something mechanical, but you hope not and intermitent noise doesn't point to mechanical. I'd say it's time to invest in a timing light. You can always try better octane. It won't hurt anything but your wallet.

yeah I thought it might be timing, but I'm going to try this first anyway. I've only heard it on full acceleration, and then the revs kick down, so that may be the sensor doing its job. I guess I really won't know for a day or two anyway, but I hope it isn't anything too serious.

Not to be the bearer of bad news, but a knocking sound coming from the block is very bad. A light pinging under load is somewhat normal, but a heavy consistent knock usually means a rebuild is in order. The fact that your sound comes and goes maybe something spark related though.

If it only knocks under full throttle then it sounds like the timings off

I just had my 305 rebuilt and man was it tore!!! 116k miles on it and heres a list of the problems

1) Harmonic balancer shifter - grinding into timing cover
2) 2 spun rod bearings
3) 1 bad rod
4) worn crank
5) 2 exhaust leaks
6) leaking oil pan
7) leaking radiator

Yeah the rod knock was the worst.. got the knock at high RPM too.. check your engine thoroughly

oh yah just to add.. with all of those problems, i still beat imports :sillylol:

I have always run 91 octane gas in my 350. Its never pinged or anything to I recomend going with that.

Yeah, that's next thanks man, if it doesn't go away then I'm going to borrow a timing light. Thanks for all the help guys, nice to get advice from people who've been there. Red arrow, you mentioned a light pinging under load, that is almost what it sounded like. It wasn't the heavy-scary type of knocking, it was just a noticeable pinging on full throttle. I may just be a dumbass who hasn't learned all the sounds of my car yet, because I didn't hear it when I took it out tonight, so I'm really confused, although I still want to put higher octane in it before I run it up to the redline again. Again thanks for all the help, I'm sure I'll have more questions as time goes on.

Sounds more like your manifolds (exhaust) are leaking like everyone else's thirdgen..

I doub't your "pinging", Unless they raised your initital timing to about 20 degrees. And if they did, your idle would be at like 2k, and you'd be running hotter than a stripper on friday night.

Good luck with your new car!

-- Joe

yeah, I got it inspected, and there's an exhaust leak somewhere. No worries, I'm still glad its mine! . I got another stupid question for you though guys, my key to the car isn't original, it looks like a hardware-cut key. I thought the originals had Pass-Key2 chips or something (that black square on the key) would not having that screw anything up?

What year is your car? I believe pass key started in 89. My 87 didn't have it but my 89 did. If your car doesn't have the chip and you are still able to start it, someone has bypassed the system.

If its an 89 theres a chance the computer could be in "limp home" mode, which will stink when you disconnect the battery and it won't start again..

Vats was spotty in 87, 88, but in most cars by 89..

-- Joe

Yeah, mines an 88, so it probably doesn't have it, the thought had just occured to me, thanks for the info. I just took it out, and I think I may have pegged down the fuel problem. I hit it leaving a light, and the revs went up to about 3500, and stayed there, no knocking/pinging/anything, and it didn't seem to want to rev beyond that. Then, the service engine light came on, so I took it slow going home, shut the car off, and turned it back on a couple of seconds later, drove it around the block, and the light stayed off. Would this mean my car is trying to tell me it wants higher octane gas? That's my amateur guess.

Take it to your local Autozone and they will scan your car for free and tell you what code your car is throwing. Its ok if the SES light isnt on, its stored in the computer. When you find out the code, you can attack the problem instead of just guessing at things. Good luck

Thanks man. I am 99 percent sure I need to reset the timing, and then I'm going to pull the codes off the engine, I'm also hopefully going to get everything I need this weekend to do a full tune-up, which should help. Again, thanks for the advice guys, I'll let you know how it works out.

I am not sure about the other year models, but the owners manual for my 90 305 tpi says to use at least a 91 octane.
Rudy

my GTA has NEVER seen less than 93 octane, especially now with the new engine...i would NEVER put 87 octane in that car(when i had the L98)

i got my timing advanced so i use 93 but thats all any of my cars have seen (88 SC, 90 IROC-Z). and that sound could very well be ur exhaust manifold.

Yeah I was a little angry that the dealership stuck me with a full tank of 87, but I've been keeping the revs down for the most part, and the tank is about empty, so I'll see how it responds to premium. My friends 97 Z-28 takes premium, so that was my guess too, but there was no owners manual when I bought the car, so thanks for confirming it Rudy, I'll see how it runs after I gas it up with 93 tomorrow.