1987 Corvette Z52

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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

We got the new hose installed last weekend and put it all back together. After a trip around the block we checked and there was oil coming from what looked like both fittings where they threaded into the cooler. So yesterday we set out to figure out the problem. We took all the shrouding back off and checked the leak while it was running and it was only the passenger's side, but we decided to pull them both. It appeared that I only put a couple wraps of teflon tape on there, so this time I put at least four rounds on there and was sure to tighten them more than I had previously. I was a little cautious cuz the fittings and the cooler are made from aluminum, but I made sure they were solidly tight this time.
After the same drive and at least one 100mph blast, we came back to dry fittings, so I think we're good to go. If the weather holds I'll be at the drags with it on Wednesday night. The only thing I would like to do before we hit a road course is to get a switch on the front electric fan. I don't remember ever seeing it work, but it's "designed" to come on at like 225 degrees. Jeezus, what were they thinking?? The fan on the backside of the radiator is on with the motor, so for all normal driving and even dragstrip/autocross, I've barely seen it go over 170, but it might like a little extra on a track day. And the wiring is simple enough to get to under the hood.

-BP
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trans cooler 5-4-24.jpg
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MostMint
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Re: 1987 Corvette Z52

Post by MostMint »

It's nice to have the fan override if you want it, but I doubt you will need it while you are on track. One thing about going fast is there is a lot of air flow. The only time I've found it handy is if you want to cool it down faster at the end of the session after you stop moving.
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

I agree. Since it's there, I figured it couldn't hurt to have the option. Probably just going to put the switch under the hood.

-BP
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

Last night coming home from the track was the first time I've driven at night with the new headlights. They are definitely an improvement, and since it was fresh in my head, and the car was in my garage, I took the chance to adjust them a little better. The right light was pointed forward correctly IMO, but was a little low, so I turned it up just a little bit. The left light was pointing way left and a little low. So I cranked it up and back towards the center more. The next trip in the dark will tell me more. It's pouring rain right now so no night drive tonight. It's super easy to adjust them so I'll stay after it, but I think if they're adjusted right, they'll do a real nice job.

-BP
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headlights new aim 5-9-24.jpg
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

So my headlight adjustment in the garage was pretty unsuccessful in the dark so last night I went out with a screwdriver at dusk and drove around making several adjustments, each one a little better, but I'm pretty happy how they turned out compared to what I had.
With last Wed being a little crazy, and a threat of bad weather, I skipped going to KMP with the quad as I wasn't ready. This morning was nice out so I drug the trailer out of the shed and hooked it up to Vette. All the lights function as designed and no weird flashing speeds or anything since all the trailer lights are LED. I found out my hazards don't work on the Vette, but I'm not going out of my way to fix that. All the other lights and directionals work as designed, so I'm good with it. I loaded up the quad (that has a small learning curve), tied it down, and went for about a 30 mile drive all over. From normal two lanes, to 70+ mph freeway runs. It's pretty warm out already and the car didn't go over 181 degrees, and that was following a pickup reasonably closely at 68mph. It does better in fresh air. I do want to run a switch so I can manually lock up the torque converter. It works a little harder at speed with the trailer and I think if it were locking, that would calm down a little, and it would run cooler too. It doesn't need that around town though.
The towing experience was good. Everything was straight and smooth. The brakes stop this rig with no issues, there's plenty of power, and handling is not a problem at all. I'm thinking I can tow with the big tires on it as there is very little tongue weight. My first dirt drag will have the big tires already on the car, but if it rubs too much, I should be able to carry them as necessary.
I immediately got one thumbs up from a Harley guy and caught a guy behind me on the freeway taking a picture. I guess it's not something you see every day.
Also, the blue markers I put on the trailer work perfectly. I see them both easily in the tiny mirrors making lane changing and backing up a breeze.

-BP
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Vette with Trailer 5-26-24.jpg
Vette with Trailer2 5-26-24.jpg
headlights better aim 5-26-24.jpg
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wxo
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Re: 1987 Corvette Z52

Post by wxo »

BP, you just inspired me. Your post on C4 headlight aiming triggered a memory. Decades ago, I bought a headlight aiming tool. (actually it only assists in adjusting in the vertical plane) I've been meaning to get Silvia's headlights aimed correctly for a long time now. Your post caused me to dig out this tool and use it. First you calibrate it to the floor at the front wheels, then you set it on the aiming pads of the headlight and adjust to get the bubble within the target area on the tool. Easy peasy! It took all of 10 minutes to get them adjusted. They were way out.
IMG_4313 web.jpg
Now I have to wait 'til it gets dark to see if there's a noticeable improvement.

BTW: I read a good tip. To turn off the headlights when they are rotated up, just set the switch back to parking position.
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

I did know the headlight off trick. A headlight aiming tool would be handy. Might worth doing it with a full tank of gas since these hold so much fuel.
Definitely needs to be DARK to know if it worked.

-BP
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

The Z52 package comes with two electric fans. The main fan on the motor side of the radiator that pulls the air through and a secondary fan on the front side of the radiator (see picture from when I was doing the trans cooler). The main fan is supposed to turn on at 225 degrees and the secondary fan when it gets to 230. WTF?? So right now the car has a 160 thermostat and the main fan comes on with the keyswitch, but the secondary fan never came on for obvious reasons. I would be shutting a car off if I saw it get to 230 degrees! The good thing is that the secondary fan has two wires and a plug that are reasonably easy to access on the LF of the car.
This past weekend we first ran a couple jumper wires up to make sure that fan actually worked. After a successful test (and it makes a BUNCH of wind and is quiet) we set out to run power and a switch to it. I'll save the boring details, but I now I have a working backup fan that makes power on demand. I think this might be useful both in towing scenarios, and also potentially during track days and autocross events where cooldown time is a minimum.

-BP
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trans cooler 4-6-24a.jpg
Fan Switch 6-22-24.jpg
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

Yesterday I took the Vette to it's first track day at Nelson Ledges. Long story short, I didn't quite finish my first 20 minute session as I lost oil pressure coming out of the carousel and the car began running a little bit rough. The theory at this point is that the stock oil pan was unable to hold the oil in place under the heavy G-load so the pickup could keep sucking successfully and I ran a rod bearing or two dry. The engine temp at this point was at about 220 degrees. I didn't get too worried about this as the factory fans wouldn't normally kick on until about 225. I also was running the oil a quart OVER full to help with this situation. I believe it lasted this far into the session because I was getting more familiar and comfortable with the car and thus going faster through the turns as the session went on. I made it back to the pits running with the oil temp warning saying I was over 300 degrees and oil pressure was at ZERO. After it sat for a long time and cooled down thoroughly I restarted it and it was showing about 14psi with cold oil so I decided to attempt to drive it to dad's which is about 25-30 min tops. It did make it and had varying oil pressure depending on RPM so I tried to not let it go to idle.

Tomorrow I plan to drain the oil and pull the pan to see what I can see. This can be done in the car apparently. Time will tell what we'll find.

-BP
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wxo
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Re: 1987 Corvette Z52

Post by wxo »

I'm not sure about yours, but I had to jack the engine to get the front bolts out of the oil pan. Not that big of a deal, though. Especially, like in my case (LT1/LT4), I had done it a few times. :lol:
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

So we were unsuccessful in our mission to remove the pan in the car yesterday. The new motor mounts don't have enough give to be able to lift the motor up without removing the bolts from them. The bolts won't come all the way out without removing the exhaust manifolds. The pan is loose and all the oil cooler stuff is already out of the way, along with the starter and inspection cover. At this point I've made the decision to just pull it out. We did drain the oil and also pull the oil filter and dissect it, and there's A LOT of debris in both (see pics).

I'm not 100% sure what I'm going to do yet, but I'm really leaning towards this:

https://www.facebook.com/marketplace/it ... 5946274094

It's roughly 300hp and 360 lbs of torque in stock trim. This would be roughly 60hp and 20lbs of torque more with way more tuneability and likely a more durable design without adding any weight to the car. There are still question marks, but I've done this before, so I think I can figure it out. Most of it is installation hardware from what I can tell.

Hopefully we can finish getting it out of the car next weekend.

-BP
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metal oil1 7-6-24.jpg
metal oil 7-6-24.jpg
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

After a few sessions, we got the motor on a stand yesterday. Not a lot of surprises as there were large bits of metal from the main bearings in the pan and in the pickup. The crank is toast for sure. I only pulled one main cap to confirm my suspicions and didn't dig any farther. When I pulled the cap the bearing would spin freely around and around and the crank looks like a topographical map. I'm sure it's not just the one journal either. Not sure about the rod bearings but I suspect they don't look too hot either.

So I'm pretty much getting my head around an LS swap of some sort. Most likely a 5.3. I was leaning towards a 6.0, but those are all in HD trucks and vans, and are too weak for all that work and get beat to shit on a daily basis just hauling themselves around, let alone a big load. A 5.3 is cheaper and usually comes in a 1/2 ton or SUV where it will have had an easier life. AND they're cheaper. They give up around 30hp to the 6.0, but are still about 50hp more than I currently have, so it's an upgrade no matter what.

Side note: While under the car, I figured out why my torque converter wasn't locking. There is a little metal bracket wire loom near the transmission wiring that was not bolted up (my fault I'm sure) and at some point it sliced one of the wires in that harness. I'm sure if I put it back together it will work. Now that I'm changing stuff, I'll probably have to put a manual switch in anyway, but it's nice to know why.

More to come as I start gathering parts.

-BP
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motor partsB 7-20-24.jpg
motor partsA 7-20-24.jpg
motor parts 7-20-24.jpg
motor outA 7-20-24.jpg
motor out 7-20-24.jpg
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GMJohnny
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Re: 1987 Corvette Z52

Post by GMJohnny »

I’m wondering why you wouldn’t buy some type of crate motor that
just bolts in to avoid all of the engineering required to drop in the LS motor.
Is LS a less expensive option?

GM
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MostMint
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Re: 1987 Corvette Z52

Post by MostMint »

The HP to $ ratio for the LS should be better, plus this one should be easier than the S10 swap
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]
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Basement Paul
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Re: 1987 Corvette Z52

Post by Basement Paul »

A stock replacement short block would cost about what the whole LS motor would cost. Yes there is going to be some engineering, but I'm by far not the first guy that's done this swap, so parts and info do exist and it shouldn't be the undertaking the S10 was. This will be about a 50hp upgrade in stock condition. If I add 50hp more to a short block, it will cost a LOT more than this swap, and then I still have to deal with the limiting TPI intake and computer chip only tuning scenario. The LS will come with complete wiring harness, computer, and accessories that I need, and if I do any upgrades in the future, the tuner can just plug into the OBDII port and do his thing.

So for me, to make this car better for the future, this seems like a logical time for the upgrade. Hopefully I'm right!

-BP
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