The "Other" IROC-Z Thread

[68bowtie]

So first of all, I don't know much about anything other than 67-72 GM pickups. But my oldest son is close to 14, and we have been talking about what he wants to drive when he turns 16. Long story short, he's narrowed it down to an 82-92 3rd gen camaro. Preferably an IROC, auto, in red.

I figure a couple years is just right to take our time and find the perfect car, and get it ready to drive. Ideally not a major project (no paint/body, no drive train swaps). Something that the paint looks decent, has everything there, and not something super nice or it would be out of our budget. And I'm always looking for a good deal.

Well what do you know, not a week into daily searching, this car pops up on cl about 6.5 hours away. Checks all the boxes, can't pass it up, only 66k miles, and a fantastic price.

It posted Tuesday, we made the deal Wed, and we drove up Thursday to pick it up. Made a family trip out of it with my wife and all 3 kids.

The gentleman we bought it from was the second owner. He bought it 3 years old in 1990. Painted it red in 1993 (it was originally white). He parked it in the garage in 2005 when he bought a second car, and didn't fire it up since. He cried when we made deal. He assured me it needed to go to someone who would use it, but I could understand his emotions.

Here's a little scenery of the trip. The ride back was late at night, pouring icy rain, in the mountains, not the kind of towing I like but we made it back safely.



Here's the car and my son. And my "patina" trailer...





The options... 305/auto, t-tops, white, IROC, limited slip, tinted windows, and I think the rest is mostly boring stuff. I didn't look closely yet though...

[Warrens69GMC]

cool!

[68bowtie]

Before coming home, I took it by a friends shop (very thankful for his generosity). Due to sitting for so long, it needed a few things to be gone through before firing it up.

First we did a general inspection. Rear end and trans were pretty clean (no apparent leaks). Everything appears to be intact. Sway bar bushings are junk.





Changed the oil and filter (my son's first run at this).



Installed a new battery.

Popped the distributor and used a priming tool to get everything lubed up. Pressure gauge confirmed everything was priming, and we spun by hand a couple times by the flywheel to make sure everything felt right.



The coolant needs to go, as does the radiator and hoses, but that's for another day.

[68bowtie]

For the fuel tank, I wanted to see if there was gas, but I didn't want to hook the battery up in case the pump turned on with the ignition and sent garbage into the system. So I sent a hand pump siphon into the tank first. I felt the bottom (or so I thought) and nothing came out. The end was dry.

So we proceeded to dump 7 gallons in with some fuel system cleaner. Well, at about 6.5 gallons, it started flowing out the top of the filler.

WOOPS

Apparently there was some gas in there. I'm still not sure if I was hitting a baffle or something in there.

So now we have been trying to drain the tank. First we tried disconnecting the supply line just past the fuel filter, and ran a hose to a bucket. Hooked up the battery, turned on the ignition. Nothing...

Then we hooked up a rag and compressor blower (lightly) in the fuel filler to put a couple pounds of air on it. Nothing came out the supply line into the bucket. Although some gas and air came back out the filler a bit, and a bit dripped out of a valve that appears to be a check valve on a vent line (not sure what this does). We disconnected that valve and plumbed that tube into the bucket and tried again. Still nothing...

Went back to the hand siphon and got it past the baffle. Retrieved about 2.5 gallons, but it's still not at the bottom because that's all we got.

So I'm thinking now to plumb my hose and bucket back onto the supply line and jumper the fuel tank harness to see if that will pump the tank down.

Open to any thoughts or suggestions...

[68bowtie]

The next steps are to change the trans filter and fluid, get this fuel tank drained and inspected, replace the sender/pump, and fire it up. Then I can get it home into the driveway.

[Warrens69GMC]

I have a 1992 "purple haze" 305 TBI Camaro

[68bowtie]

I’ve never heard of that. Got any pictures?

[Warrens69GMC]

Not mine

[68bowtie]

Sounds rare...

[CAMAROBOY68SS]

Originally Posted by Warrens69GMC

Not mine

Somewhat rare for Z28, lots of RS cars in the purple (at least around me growing up when they were everywhere) Probably the second rarest color in a Z/28 next to the Teal. Mad a zillion Teal RS cars, but no many Z's.

[CAMAROBOY68SS]

third gen is a perfect first car nowadays, looks flashy but not overpowered. Luckily these cars have gotten old enough that restoration companies are now making parts for them. Last time I had a 3rd gen it was when your were picking bones for parts. That one is super nice, getting harder to find clean IROCs and Z28s

Once you get it running would not be a bad idea to check the t-top seals and actually pour some water over the top with them in and check for leaks, doesnt take much for them to start making a mess inside, and you know he is gonna have them out all the time once weather is good, lol. I know I had mine out all the time with my t-top 4th gen in high school.

[68bowtie]

Thanks for the advice on the t-tops, it’s gonna be in the driveway now.

Yeah I’m glad there are parts available. This one will need some cosmetic work. It’s a beauty 20-footer, but up close there are some warts… lol For a future post.

[57taskforce]

The oe filler neck won’t let your syphon hose get to the bottom of the tank. I fought this on mine before I just pulled the tank. To get the tank out be prepared to take the whole rear suspension apart, and the rear half of the exhaust off to get it out. The axle has to droop way way low to get the tank to clear. It sounds a lot worse than it really is. Took me about 1.5 hours just taking my time to get it out. (Way less putting the 4th Gen tank back in) I knew there was fuel in it but with the pump shot I couldn’t get it out. Mine was about 1/4 full and the front leading edge of the seam between the top and bottom halves of the tank was rusted thru from the inside. Once you get a working pump in it you can jump the ALDL connector under the steering column and run the pump. If you pull the rubber supply line off of the fuel rail under the hood you can flush the lines in their entirety with fresh fuel. Make sure and replace the viton orings on both sides of the under hood rubber fuel lines. while I had the tank out I blew air from the engine compartment all the way back to get all the crap out of the supply and return. Make sure and Change the filter. Also if you pull the rubber under hood return line off at the same time as the supply you can run a little air thru the supply and flush the old crap out of the rail before you send it to the injectors. Put a hose or bottle or something similar on the return from the intake or it’ll make a hell of a mess when all that stuff from the rail comes flying out, ask me how I know. The rail and intake lines hold a lot more fuel than I thought they would. The 85-87 cars have better injectors than the later ones. After sitting 20 years I have not had to replace mine. Dont be surprised if your pump looks like this.

Here’s my thread on tgo. Going by my Camaro related forums username of course. It outlines everything pretty detailed I did to get mine running after 20 years.
https://www.thirdgen.org/forums/memb...-new-here.html

I learned a ton about the tpi setup thru this whole thing. If you need anything at all don’t hesitate.

[57taskforce]

Also the white check valve looking thing is actually the tank over pressure relief. If it isn’t functioning in a stock system it’ll cause problems with the pump not picking up fuel and it can cause fuel to dump out the side of the car past the gas cap.

For fuel pump circuit testing/running the pump with the engine off, jump 12+ power directly from the battery to pin G on the ALDL (computer diagnostic plug) see diagram below. If everything is working correctly this will turn the pump on until power is removed.
Something I discovered about the pump wiring is that the relay setup on the firewall, (part of the ALDl circuit) only supplies power via the ecm to the circuit for 5 seconds to prime the fuel system when you first turn the key on. Once the engine is running the fuel pump is actually powered via the oil pressure switch on top of the back on the engine block.

Just a bit of side info in case you ever have to diagnose power problems with the fuel pump circuit(s). You just never know what you might fight with one that has sat so long. I got lucky and the power side of my system had no issues.

[68bowtie]

This is all super helpful, thank you. A couple questions:

Where are these viton o-rings exactly? I don’t have the car close by and I want to get the right ones ordered. I do plan to disconnect supply and return lines at the rail to blow them out.

Could you post a pic of where to find the connector under the hood?

[57taskforce]

Ab-so-friggen-lutely, the fuel lines are circled below. The orings seal the rubber supply and return hoses on both ends so 4 total orings to replace in the engine compartment. They slip over the end of the metal lines and then the rubber hose ends seal to the oring. It’ll make perfect sense when you tear into it. I used this kit when I removed these lines because I wanted to have plenty on hand for future endeavors but I’m sure any local parts store should have them. They have to be gasoline safe. The bigger of the lines is the supply and the smaller is obviously the return. Blow them out on the intake side and the body side both, on the supply go all the way to the filter with it removed, and from the filter inlet to the sending unit connection. If you keep the OE style sending unit you’ll need the same viton orings for those connections as well. Make good and sure the rubber lines from the body hard lines to the intake hard lines are in good shape, the last thing you want is a a major fuel leak next to the exhaust manifold.


https://www.jegs.com/i/JEGS/555/W523...SABEgLJmPD_BwE

[68bowtie]

10-4 rubber ducky!

[57taskforce]

Looked over your spid a bit, not too bad you’ve got a package b (mid option level- code 1SB) Iroc (B4Z) and it’s a G92 car like mine- the performance 10 bolt rear option with disks and 3:23 gears, Posi etc. pretty good upgrade over the drums, and 2:xx gear a lot of them had. The 9 bolt borg Warner rear is a little stronger, but you can tell this one has a 10 bolt by the GU5 code. The BW’s used different ratio codes than the 10 bolts.
Not too shabby.

[youngrodder]

Cool thread and story. Those 3rd gens are increasing in value. You bought at a great time. A lot of people cut an access hole in the trunk floor and make a cover so if you ever need to change the fuel pump in the future you can do it from the top side. Now would be the time to think about this modification. It could all be hidden under the factory carpet.

Following along.

Oh, your son must be stoked.

Marc

[68bowtie]

Changed the trans filter and oil while it was on the lift. Everything looked really clean.

[68bowtie]

Tried to jumper the G terminal on the fuel pump harness inside the firewall with no luck. Pump must be bad. That’s ok the new one is on the way already.

So we had to pull the exhaust and rear end and fuel tank.

We never could get the fuel drained so 3 of us man handled it out full to the brim. It was tricky getting it past the filler neck. But we were successful. I’m tired now…

[57taskforce]

Nice! Yea that tank was a pain in the ass at 1/4 tank with me wrestling it out on my back. I can only imagine the joy you had with it being full. Im glad my new tank has a removable filler, the heat shield and exhaust are all that needs to be removed now to get it out. While you’ve got it at that level of disassembly, check your transmission extension housing bushing and tail shaft seal really close. My was leaking pretty good at only 50,000 miles. The bushing was worn, which is another common problem with the 700r Fbody transmissions. Your transmission looks pretty nice. Mine still shifts great, hope yours is the same. Im going to do the corvette servo mod to mine pretty soon. I put dex6 back in mine and am pretty happy with how it shifts and performs. Supposedly 6 runs cooler 3 with no other adverse effects. Im confident I’m the only one to ever pull the pan on mine, looks like yours might be the same going by the pan sealing surface on the case.

[68bowtie]

Cool. I’ll have to double check but I didn’t notice any leaks around the tailshaft.

[CAMAROBOY68SS]

Originally Posted by 68bowtie

Cool. I’ll have to double check but I didn’t notice any leaks around the tailshaft.

might not be leaking now, but if the car has been sitting awhile, once you start driving it and its going through heat cycles, old seals will start to go. So not a bad idea to change it, if its easy access at this point. My grandparents had a 83 Z28 they bought new and didnt drive it much until about 90/91. As soon as they started driving it more, everything started leaking.

[LS short box]

Looks like a fun project. Almost bought one until I found my 80 Camaro project.
Maybe a LS swap?
There is a company in the MPLS area called TPIS. They do all kinds of tuned port stuff.
Having said that maybe its not a bad thing to have a lower powered car for new driver.
Good luck with your project.