1990 Corvette Z51

Update your progress on your various car projects.

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TireSmoker
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Re: 1990 Corvette Z51

Post by TireSmoker »

I got my gauge cluster and climate controls back from batee.com this week. They fixed the tach and re-applied a film to the LCD -- mine was 50-60% worn. They said the climate controller was actually OK. There's another piece called the climate programmer (??) that might still be bad. In the mean time, I'll put this all back together and hopefully have a working tach.

Next up, headlights...

-Dave
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Re: 1990 Corvette Z51

Post by TireSmoker »

So after getting the gauge cluster back, I installed it in the dash. As I usually do, I just put minimal stuff together to make sure it works before I put it all back together. I started the car and tach needle moves and seems accurate, but it doesn't seem to move smoothly. I didnt wanna whack the throttle on an ice-cold motor to really test it out, and it was cold enough I didn't wanna leave the garage open on that night.

I sent them a note and said I would send them a video of it. I still gotta do that.

-Dave
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Re: 1990 Corvette Z51

Post by TireSmoker »

I've run out of things on the other cars to procrastinate with, so I got back to this today. I finally took a video.. tell me what you think about the tach movement.

https://files.tiresmoke.org/f/0cdf1f870d52452ca718/ (138mb)
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Re: 1990 Corvette Z51

Post by wxo »

Definitely not moving the way it should (like mine does).
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Re: 1990 Corvette Z51

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The guy who fixed it, Bryan @ batee.com agreed. He responded to my email within a half hour. He said to send it back, they will take care of it.

-Dave
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Re: 1990 Corvette Z51

Post by TireSmoker »

I've been driving the Vette a bit the past couple of weeks, even going to work a few times.

The dash is still kinda glitchy and is very annoying. The backlight behind the digital speedo flickers constantly. The tach needle is still somewhat bouncy, although its still way better than before I had it fixed.

I've been trying to run it regularly so that I don't have to keep unhooking the battery. I've also run a couple bottles of Techron through it, but something seems to have made things worse. It starts and idles fine, but while driving it the past 2 times, it can't take more than about 1/2 throttle before it starts mis-firing badly. Under that threshold, it seems to run fine. I'm not sure if there is junk in the injectors or if the fuel pump is failing and can't deliver enough flow. I'm inclined to believe its the injectors since it was after I put the Techron in.

Winter projects so far:

Remove injectors for cleaning and/or replace fuel pump
Replace brake booster
Gut catalytic converter (eliminate rattling) and replace header collector gaskets
Fix headlight motors
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Re: 1990 Corvette Z51

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I drove the car again this today and this misfire was even worse, especially in the beginning. Whatever the Techron knocked loose, I think they need to come out for a real cleaning. I've never really had to clean injectors like this before, and boy did I pick a doosey to start with.

The Accel SuperRam has 17 fasteners to hold the lid on. No biggie, right on top. I've read in the past that these intakes are PITA to work on. Once I got the lid off, I quickly understood -- there are 16 more fasteners *from the bottom* that hold the plenum to the runners. And they are 12-point 1/4" bolts. I can't get my ratcheting box wrenches on all of them. I'm gonna run over to Tony's garage to see if he has a 1/4" 12-point socket.

Once the injectors are out, I'm going to reach out to a place called Cleveland Injector Hospital to get them serviced.

-Dave
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The SuperRam is a stupid intake

Post by TireSmoker »

The injectors are finally out, but wow, what an effort to do so. This is such a trivially easy job on almost any other Chevy EFI intake I've played with -- my StealthRam, a 4-bbl single-plane EFI, Ramjet. But on the SuperRam, it is a several hour job. Actually, of those 16 bolts from the bottom, only 4 are really hard. The other 12 arent bad. Some suggest threading a stud into the 4 difficult one and using a nut from underneath.

Because the coolant runs to the bottom of the throttle body, and I needed to get it out of the way, I ended up draining the cooling system. Good news there, the coolant in there looked very good.

I thought I was going to have to remove the runners from the base to get the injectors out, but instead I was able to slide the little clips the hold the injectors into the rail so that I could pull the rails and leave the injectors in the place (I'm sure Walt, Andy, Paul all are probably familar with the clips). The runners block them from all coming out together. However, once every thing was out, the fuel rail itself looks pretty clean inside. Nothing of concern.

What was concerning was how loose the fuel rail feed/return fittings were when I took it apart. Seemed barely more than finger tight. The o-rings are clearly ready for replacement too.

The numbers on the injectors are 0 280 150 947, which come up as 25lb/hr @ 43.5psi. Commonly used on 460 Fords.
https://www.injectorplanet.com/collecti ... d-f1te-d1a
They quote $15/each for rebuild service. That gives me a point of reference. I'm going to see if Cleveland Injector Hospital, being local, can come in around the same money.

I'm excited to see how well thing thing will run when I'm done!
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Basement Paul
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Re: 1990 Corvette Z51

Post by Basement Paul »

Those look pretty rough towards the spray end.

-BP
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Re: 1990 Corvette Z51

Post by TireSmoker »

I picked up a gasket set for the SuperRam at Summit last weekend. I also picked up some long 1/4-28 screws that I can cut into studs. Of the 16 bolts, only 4 are really tough. Some people make studs for those 4, which is supposed to help out a little bit.

I got the injectors dropped off to Cleveland Injector Hospital, which is just some dude's garage on the west side. He had a 6.0 LS turbo in a Lexus SC idling when I showed up, and I said "Sounds like I'm in the right place!" Between his glasses and black hair, he kinda looks like Tony Angelo (Hot Rod Garage / Stay Tuned on youtube). He has a pretty serious looking injector test bench. He says his typical turnaround is a week.
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Re: 1990 Corvette Z51

Post by TireSmoker »

Injector guy texted me this morning and said mine were ready. I asked if they were bad, and he said "no, not really."

Hmm.. really makes me scratch my head why the car was running so poorly before I took it apart for this job. At least these will no longer be a question mark. Pretty sure I've replaced the fuel filter before. I guess a fuel pressure check will be next when I get it back together.

-Dave
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Re: 1990 Corvette Z51

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I picked up my injectors and got started on the re-assembly process over the weekend. I got all the old gasket surfaces scraped and otherwise ready. The o-rings in the fuel rail feed & return lines look due for replacement, gotta dig up replacements. I cut the 1/4-28 screws into 4 studs and threaded them into the plenum. I bought some normal 6-point nuts for the studs but remembered I have these sorta trick ARP 12-point thin-wall nuts that came with something else. Chris is scanning in the gasket set I bought into Cometic's system.
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Basement Paul
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Re: 1990 Corvette Z51

Post by Basement Paul »

So what happens after they get scanned into Cometic's system? Do you get a free set? Are they going to offer them for sale? Just curious.

-BP
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Re: 1990 Corvette Z51

Post by TireSmoker »

Ehh, for me, probably nothing. Hopefully I don't need another set! But they'd be in their system if someone needed them.
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Re: 1990 Corvette Z51

Post by Basement Paul »

At least it will ensure their existence in the future.

-BP
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