1988 Convertible for sunny day drives

[Tourmax]

Well, picked up the last thing I needed to “tune” the fuel injection:

Wideband O2 sensor kit. Only way to calibrate WOT. A nice plus is it has a 0-5v analog out that my apu1 can accept for datalogging. That means I can just drive the car and download the log afterwards instead of trying to drive the car, watch the road, watch the rpm, watch the o2 gauge and somehow try to remeber what I have to adjust at what rpm. With the wideband, I just do a run, analyse the data, make my changes and do another run right away. With the “real time tuning” function of the apu1, I don’t even have to shut the car down to make adjustments.



Also, it appears I was making a GM performance parts intake from the lt1 intake manifold without even knowing it:

Thats a “ramjet 350” intake. It follows the old rochester mech fi manifold design, but updated for electronic fi. Sold by GMPP, Arizona Speed and Marine and as a marine intake for the marine GM 350 by Mercruiser. Essentially, its an lt1 intake with water crossover passages, a thermostat housing and a “pop up” roof.

Heres the dyno chart from the ramjet 350 crate package:

Just look at that torque curve! More like a table top than a curve! Around 360-375 lb/ft at 1750 rpm! Thats pretty much right off idle! And its still making 300 lb/ft at 5500 rpm! Cranks out 350 hp at 5200, which is about 4-500 rpm more than where the stock TPI lays down. He k, it makes the L98’s hp peak numbers at 3200 rpm and just keeps on going up from there. Even when it hits the L98’s “wall” at 4800, it stays a good 100-ish hp over the l98 all the way to 5500 rpm!

What a fantastic street engine! It should be one heck of a fun powerplant in my tiny c4 ’Vert!

Now, granted, that chart is engine dyno and likely NO accessories and headers out to atmosphere, but those are still numbers not to be taken likely. That should push a C4 deep into low 13’s in the 1/4, maybe even high 12’s.

The thing about the ramjet 350 is it’s just a plain ol’ 2 bolt main, cast crank, iron block, gen 1 sbc. It even has a cam with similar specs to the l98 cam (actually, its even a little “smaller” than an l98 cam).

The only appreciable difference from the l98 is the ramjet has vortec heads. The vortecs flow better than the 113 vette heads, but I’m sure I can port the 113’s at least close to the vortec flow numbers. The D-port aluminums actually arent that far off the vortec numbers @ 0.50 lift. L98: 193/161 vs vortec: 239/147. Exhaust already outflows the Vortecs. Intake kills the L98, but I’ve read of getting up to 239/192 with a good port job. Thats serious vortec (unported) territory...

wife ran into town today (her mom’s birthday) and picked me up some 6061 Al at the metal store while she was in there. Picked up a 2x8’ sheet of 1/8” and a four 1x1 1/8” wall square tube. Sheet is for the intake build, square tube I need for a few things on the argo.

I should be back to welding up the intake soon. I just have to sort out a few small details first, like rebuilding the egr and vacuum passages and I’m thinking of lengthening the runners a bit for more low end torque...

 

[Tourmax]

Well, argon bottle ran out so no more tig welding tonight. I’ll get a new bottle tomorrow morning.

So I moved on to working on the 52mm throttle body I bought earlier last year.

its for an LT1, so a few things are not right for the L98. The throttle cable, TV cable and cruise cable attachments are different. Luckily, the 52 mm TB had a bolted on cable pulley. So all I had to do is unscrew it and off it goes.

I grab an old L98 TB to swap out the cable pulley, but the L98 pulley is peened on the shaft.

No problem.

Grinder, some careful work and off it comes. It indexes the same as the LT1 pulley, but the hole is too small to go on the lt1 shaft. That might be because this is an AS&M "bored out" TB and the shaft might be proprietary. So maybe if someone was to swap on a stock LT1 TB the file work may not be necessary.

Well, we can fix that little issue. A little work with the swiss files and:

And just like that, 52mm LT1 TB with an L98 pulley.



All it needs now is a new TPS. The mounting points on the LT1 TB won’t accept the L98 TPS but fortunately, the LT1 TPS outputs the same signal as the L98 TPS. All I have to do is change the plug on the harness to the LT1 TPS style and Bob’s your uncle!

Coming along nicely. In a couple days, I should have something that actually looks like an intake manifold....

 

[Rruuff Day]

Well, argon bottle ran out so no more tig welding tonight. I’ll get a new bottle tomorrow morning.

So I moved on to working on the 52mm throttle body I bought earlier last year.

its for an LT1, so a few things are not right for the L98. The throttle cable, TV cable and cruise cable attachments are different. Luckily, the 52 mm TB had a bolted on cable bellcrank. So all I had to do is unscrew it and off it goes.

I grab an old L98 TB and the cable bellcrank is peened on.

No problem.

Grinder, a little work and off it comes. It indexes the same as the LT1 bellcrank, but the hole is too small to go on the lt1 shaft.

A little file work :

View attachment 36827
View attachment 36828

And just like that, 52mm LT1 TB with an L98 bellcrank.

All it needs now is a new TPS. The mounting on the LT1 won’t accept the L98 TPS. But fortunately, the LT1 TPS outputs the same signal as the L98 TPS. All I have to do is change the plug on the harness to the LT1 TPS style andBob’s your uncle!

Coming along nicely. In a couple days, I should have something that actually looks like an intake manifold....

Always great to see a plan coming together Tour...

 

[Tourmax]

Well, committed now:

Thats the vacuum passages and the EGR passages rebuilt. Which means that the front half of the manifold is now welded to the rear. It's just the passage housings right now, but I'm pretty much committed now to finishing it.

Coming along.....

 

[Tourmax]

Decided to do a light color sand and buff:

I can actually watch the television on the wall in the hood paint now.

it’s certainly not perfect, but it is a 10-15 year old (might be older) re-paint job. It’s only ever going to come back so much. Theres still some imperfections in it, but you’d have to do a full re-paint to fix them all.

But thats still pretty good for a little bit of elbow grease.

Oh, those pics are also with nothing on the paint. No glaze, no polish, no wax. Its just been compounded and wiped clean.

Polish and wax will certainly make it “pop” even more.

I love it when you can get the “wet” look on vehicle paint.

 

[Tourmax]

I thought I’d show a bit of the process, just in case anyone is thinking of color sanding.

First, you have to get your mind right about doing this to your nice shiny paint job:

Thats wet sanded with 2000 grit wet/dry.

Then, its on to compounding:

Thats the first pass with the compounding pad on the rotary buffer. If you zoom in, you can see the “haze” and maybe even the scratches that are still there.

Then, second pass:

Scratches gone, just nice clean shiny paint.

But the thing about a rotary buffer is you have to know what you are doing and be very careful with it. Its a serious piece of professional grade kit and like anything “pro grade”, you can do serious damage in an instant if you mess up.

Here’s what a moment of carelessness can do:

Notice the missing paint at the base of the spoiler pedestal? That was literally a split second touch with the yellow 6” pad on 3000 rpm.

One split second touch and....POOF!

Paint gone right down to the parent material. Fortunately, its an easy fix with the touch up paint. But it shows you what happens if you get careless, let alone what you could do if you don’t know how to use a rotary....

 

[Live Wire]

Welcome to the forum! Your story is similar to mine... Recently retired construction electrician, but with 24 years in CF reserve, as a CIC officer. I've been working on my newly acquired 85 C4, and I'm not really interested in bringing it back to stock, but I want to have it as a functional, but fun car with my own touches and conveniences, to drive daily if I want. Not being a Corvette guy, ever, (past: Dodge, Ford, BMW) I couldn't turn down the deal to buy this car. It had a lot of small problems, including several wiring glitches and the wiper motor problem like yours. I've replaced the sound system, which was totally butchered, and most of the interior light bulbs with LED's as I found the interior lights just too dim. This week has been about draining and replacing dark and waterlogged brake fluid with new DOT5 (no ABS so no problem), and sprucing up the engine bay with some paint and polish, as well as re-setting the ignition timing as the engine was pinging itself to death under hard acceleration. Turned out it was set at about 14 degrees BTDC (ridiculous!). Anyway, have fun with the tinkering, as we all don't have much else to do these days.
Enjoy!

 

[Tourmax]

Anyone who’s ever owned a c4 knows that the interior is just a cornucopia of rattles and squeaks. It’s all that leather up against plastic that generates all those noises.

The C4 is a heck of a handler, but all that squeaking leather/plastic just makes it feel cheap and ruins the oh-so-satisfying feeling of railing around a corner or cruising down your favorite country road.

So, time to exorcise those squeaks.

First up, the biggest interior offender: seats.

The headrests are a big noise source for seats, with the seat belt being a close second. The double whammy of the headrests squeaking is its right there by your ears, so it sounds like the interior is coming apart when they squeak.

We can handle that, so headrests first.

Take a bit of felt (I used black because my interior is black):

Cut yourself a nice thin strip:

and insert it between the leather and plastic backing:

Just like that, you’re eliminated that nasty squeak in the headrest.

Add a little bit of glue (your choice, I usually use 777 or contact cement) to keep it from slipping down or up and you’re done.

Next up: squeaky seat belts and then on to the smaller noise generators....

 

[Tourmax]

Well, now I’m flipping back and forth on the engine again.

Specifically, to swap out or modify the TPI.

I like originality, but I’m not a big stickler for it. I’ll modify anything if it makes sense to me.

But, the L98 works soooo well in street driving. Its just got that nice satisfying “grunt”. Sure, it runs out of breath around 4500-5500, but I not sure I really care about that anymore because ot does what I want and it does it very well.

I will still finish the modified LT1 intake, bit it might end up as a wall hanger.

As a minimum, the TPI unit will come off the engine for a good metal polishing.

I guess we’ll see at that time if I want to drop the LT1/ramjet intake on the block or if the TPI goes back on....

 

[Tourmax]

Hmmmm......

 

[Stanky86]

Not the biggest fan of that particular steering wheel. But it’s not really my car so giver if that’s your style.

 

[Tourmax]

Not the biggest fan of that particular steering wheel. But it’s not really my car so giver if that’s your style.

Wouldn’t look exactly like that when done.

thats a CTS-V steering wheel. I last had it on a 1998 GMC K2500. The center is made of fiberglass.

The leather would get dyed black, center cover reworked, painted black and a C4 horn button center. Wood would get stripped, stained like a black wood finish and re-varnished. Or maybe just painted black.

The big thing is the buttons. I’ve re-engineered all the circuits on the button PCB’s, but I need a clockspring to fit inside the column. Problem is; I don’t think the column is wide enough to fit a clockspring behind the wheel, which would kill the whole idea for me.

 

[Tourmax]

Well, the 'vette is mostly done up to the polish stage. After that, it's just a coat of wax.

But, after fighting some holograming I inadvertently caused in some of the panels, I finally broke down and purchased a long throw, dual action polisher.

I'm not in a postion to pay the astronomical prices the brand names want (starts at 400 bucks and up) so I went with an "import":

It's the same model as the "HYET" ones that you see discussed in youtube videos:




It's considered "entry level", but it has some high end features added. it will work fine for the 4-5 times a year I’ll use it.

I'm not overly worried about it being Chinese built as they all are these days in one way or another. It will do the job of polishing and waxing just fine.

My Dewalt rotary can still handle the heavy lifting (cut and correct) and this unit will handle the polish and wax stages. Those are very light work stages for any polisher/buffer.

I'll have a few modifications to do to it when it arrives, but nothing serious.

Reports are the body is just a bit too long and strikes the backing pad, which eventually causes the backing plate to fail. A little trimming of the plastic case will fix that.

The other thing seems to be the grease in the 90 degree head gearbox is reportedly poor quality stuff. Some have even reported that the grease feels “gritty” when they opened it up. That could be contaminated grease, poor quality grease or perhaps its aome metal filings from the gears bedding in. Whatever the reason, thats easily fixed by pulling it apart, a quick clean out with a varsol wash and then re-grease with some good HP moly grease.

165 Cdn shipped to my door.

For comparison, my Dewalt rotary was nearly 400 bucks.

For what it is, that's not a bad price at all!

 

[Tourmax]

Well crap sticks.

charged the a/c today and tried it out.

nothing.

what? Rebuilt/resealed compressor and charged and no air at all????

on goes the guages. Start the engine and the pressure starts climbing. Seems normal.

but then the pressure just keeps building! When it tops the guage I hit the bleed valve to let pressure off and walk around to shut the car off.

Well, I’ve obviously put something together wrong. Unfortunately, the only place that can be is inside the compressor itself.

I pull it off the car and break it down. As soon as I pull the front half off the piston section I see it: reed valve is on backwards. They’re keyed to only go on one way, but if you flip it over you can install it out of place, yet still be on the locating dowels.

Proof that if you make something idiot proof, they’ll build a better idiot!

Lol!

I tear the compressor all the way down to make sure nothing else is wrong. It all looks good, so back together she goes:

And there she sits.

time for supper. I’ll probably put it back on tomorrow, pull it down and then charge it up.

can’t imagine what else it could be other than that reed valve not discharging like it should...

 

[Tourmax]

Well, up and running again:

It will blow cold, but the compressor is short cycling so it’s not cooling as well as it should.

short cycling is that quick on-off the compressor clutch will do when the charge is low.

pop the gauges on and its confirmed: low charge.

I’m out of refrisgerant, so nothing nore to be done for it today. I’ll run out tomorrow and get another fill.

right now I’m sitting in the driveway baby-sitting it while it burns off sone oil spilled on the exhaust. Its actually smoking like crazy in that pic, it just doesn’t show on the camera.

smokey smokey.....

 

[gone]

When you're done and looking to get your original purchase price of $9,000 for it...let me know. I'll be one of the first to risk COVID and catch a flight to the Maritimes so I can drive it back to Alberta...

Thanks for the entertaining and informative blow-by-blow reno story; it's great to see a nice older Vette being given a second wind. I'm sure it will be a real beauty when it's completed. But wait: it already is!

 

[Tourmax]

When you're done and looking to get your original purchase price of $9,000 for it...let me know. I'll be one of the first to risk COVID and catch a flight to the Maritimes so I can drive it back to Alberta...

Thanks for the entertaining and informative blow-by-blow reno story; it's great to see a nice older Vette being given a second wind. I'm sure it will be a real beauty when it's completed. But wait: it already is!

9G?

not a chance!

lol!



it was bought as an “enjoy it for a while and sell it on” summer car, but I’m beginning to think its found it’s forever home.

I’ve always had a soft spot for strays.....

 

[Tourmax]

Well, chucked a can of refrigerant in the Vette and the AC now runs normally. Well, it's pumping and not short cycling that is. The performance at the vents varies between very poor and not cooling at all.

Well, that's contamination in the refrigerant. Obviously, I didn't pull it down far/long enough to clear the air and H2O hanging around inside the system.

I hooked up my cheapy vac pump and........nothing. Crap, The pump packed 'er in on me. That also may explain why it didn't evacuate the system (IE: completely) last time I used it.

So I popped a couple bucks on a new pump and gauge set:

Not high end by any stretch of the imagination, but it will work fine for the few times I need to bother with vehicle AC systems.

It's also shipping out of Ontario (not China, although it is a "made in china" thing), so it has a half decent chance of showing up on time. If it's coming out of china these days, you're lucky if it shows up at all......

 

[Tourmax]

‘Vette got another stablemate today:

Time to do some more work on the 83.

The vette is waiting for the new orbital buffer and A/C vacuum pump to show up and the FJ is waiting for parts.

the Mustang needs the brakes and the fuel system plumbed, so that should keep me busy for a little while...

 

[Tourmax]

New ac ac pump showed up today. Pulled the stem down:

Worked fine. Pulled it down to -30 in/mg and it held for a good 45 mins. Good to go!

Tomorrow, I’ll let it pull a vacuum on it for a couple hours to boil off any water and air still hanging around in there.

Only thing I have to do now is make an adapter so my fill hose can take my refrigerant containers. Easy peasy, just make a nice little AL block with the right sizes holes/threads to take both pieces.