89 Corvette Mostmint #39

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wxo
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Re: 89 Corvette Mostmint #39

Postby wxo » Thu Jan 24, 2019 9:26 am

Have you seen the article by Marlin Davis in the Dec 2018 Hot Rod magazine about hot rodding a 350 TPI engine? I can provide a copy if you want it.

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Fred32v
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Re: 89 Corvette Mostmint #39

Postby Fred32v » Thu Jan 24, 2019 3:58 pm

I'll give the MintOne my copy the next time I see him. :)
Fred32v
GMC Canyon Crew Cab Short Box 4x4 V6!

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MostMint
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Re: 89 Corvette Mostmint #39

Postby MostMint » Thu Jan 24, 2019 8:29 pm

It should be interesting if there is anything I can apply from that article.
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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wxo
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Re: 89 Corvette Mostmint #39

Postby wxo » Fri Jan 25, 2019 7:05 am

Andy, I've scanned the article. I'll send it to you via email. It's a PDF file.
I've sent it to bfusa.com. The only one I have right now.

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MostMint
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Re: 89 Corvette Mostmint #39

Postby MostMint » Fri Jan 25, 2019 11:17 pm

Thanks. Looked it over.
* 383 stroker - illegal
* aftermarket intake runners - 50 points
* conversion to SFI - legal - but admittedly will not add much value
* AIR pump replacement - done - 5 points
* larger throttle body - 50 points (not sure might count in the 50 for intake)
* camshaft - 50 points
* headers - 25 points
* distributor or aftermarket ign system - 20 points

The unmodified car starts at 375 points with the automatic transmission. We can go to 500 points without taking penalty laps but we are going to use at least 50 points on Accusump and engine/trans oil cooling. While not in the article, I think the aftermarket ignition might be a worthwhile investment to have a rev limiter, which means we have 375+50+20+5 = 450 points spend with 50 to go.
[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: 89 Corvette Mostmint #39

Postby Basement Paul » Sat Jan 26, 2019 12:01 pm

From what I remember, the intake runners would be a pretty worthwhile investment. They help on the high end, but the torque gains were significant as well. These were pretty limiting in stock form. Especially if you could combine it with the throttle body upgrade.

-BP

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MostMint
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Re: 89 Corvette Mostmint #39

Postby MostMint » Sun Jan 27, 2019 9:47 pm

Working on a temporary gauge panel. Have a fuse box and a bus bar for the ground and for the gauge lights. In this pic there are only two gauges but I have five installed now. Engine water temp, engine oil temp, trans oil temp and air fuel ratio. Also bought a six wire connector to use for the sensor wires that needs wired in.

1DC9B942-3EA5-4A2D-9930-E70D78519291.jpeg
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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MostMint
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Re: 89 Corvette Mostmint #39

Postby MostMint » Sun Mar 10, 2019 9:01 pm

Two work sessions on the Vette since last update:
1) Installed the RF inner fender center section. Took a bunch of fabricating since the part we had was from an earlier model and GM changed the part.
2) Fixed the targa top it had some bolts loose on the support bracket at the top of the A pillar.
3) Replaced the RF headlight frame (discovered the headlights pop up OK but they don't come on
4) replaced the melted right side rocker panel
5) installed the new master cylinder
6) installed cradle to frame brace on LF (used a couple nuts from the Charger to secure this)
7) more prep work on the exhaust manifolds for the straight plug heads.

I also got license plates yesterday. Hoping for a road test soon.

In between this I did update the temporary gauge panel
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[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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MostMint
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Re: 89 Corvette Mostmint #39

Postby MostMint » Sun Mar 10, 2019 9:19 pm

Some additional pics
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[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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MostMint
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Location: planning a race

Re: 89 Corvette Mostmint #39

Postby MostMint » Sat Apr 06, 2019 1:47 am

Took the car for a test drive a few weeks back. Suspension feels good, brake pedal is right up, car tracks straight. This engine does not rev - it's done by 4500 RPMs. You can feel the torque - it puts you back in the seat. We did uncover a couple issues: some type of grinding on left rear, and cooling fans do not come on.

Found a deal on a fiberglass top so I bought it - can't race with the glass top

Spent a little time on level 2 weight reduction - removing heater core and supporting ductwork on the passenger side last weekend. I also made a list of all the electronics that are staying and those that are going.

Yesterday Kurt and I worked on some additional weight reduction. Focus now is on wiring. my friend Mike took 90 lbs of wiring out of his 90 Corvette so I know there is potential. Kurt started in back, and I went to work on the passenger door. The door has many wires: power mirror, heated mirror, power lock and switch, power window, courtesy light, door ajar/vehicle security, speaker, rear hatch switch. They are now all gone from the passenger door except power windows.

I have also removed the tape/bundling wrap from the harness on the passenger side enabling removal of now obsolete wires.
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[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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MostMint
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Location: planning a race

Re: 89 Corvette Mostmint #39

Postby MostMint » Thu Oct 24, 2019 11:58 pm

Looks like work is to resume on this car :)

Updates:
1) Thanks to BP a set of four 285/40/17 Conti's are in the garage. They are just 5 years old they should work for drag racing and maybe a track day
2) The rear calipers are not available anywhere right now. No cores mean they can't be remanufactured. Going to have to do rebuild kits
3) Put together a list of to do's to get ready for a drag strip shakedown or a track day. Track day will be light use due to lack of beefed up transmission cooling, lack of brake cooling, lack of proper oil pan baffling/accusump
4) I acquired a set of C5 calipers and rotors for $50. Was going to turn these in as cores, but might end up converting over to C5 brakes just for parts availability. Will weigh the parts to compare. 17" rims will fit over base model C5 brakes.
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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MostMint
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Location: planning a race

Re: 89 Corvette Mostmint #39

Postby MostMint » Sun Oct 27, 2019 7:16 am

On Friday I acquired wiper arms and a pair of used rear calipers for $100. Also started the car and moved it out of the back of the garage

On Saturday
- put the car on scales it weighs 2884 with passenger seat and very little gasoline
- installed the bulbs on the 3rd brake light and reassembled it - now working
- idiot light for brakes was lit on the dash. Traced that problem to the ebrake. If the ebrake is set the switch completes the circuit. So when the switch fails the circuit stays completed. To address this I removed the wire.
- started troubleshooting cooling fan. Fan appears to not come on by 230. I checked several things - fan is good, diagnostic port can be used to make the fan turn on, leaving the circuit for the ECTS. I tried checking the voltage coming from the ECU - which seems to give an error in my meter. After that I decided to run it and warm it up. During the warm up I noticed the temp at the gauge was noticeably higher than at the thermostat. I then noticed it was leaking gas in the back. It's a steel fuel line again - naturally this ended my test.
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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MostMint
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Location: planning a race

Re: 89 Corvette Mostmint #39

Postby MostMint » Tue Oct 29, 2019 12:40 am

Last couple days:

- rear calipers rebuilt and installed
- LF caliper installed
- wiper arms installed
- defective fuel line removed and replaced with copper (temporary). It was another pin hole rusted from the inside. Will need to replace entire line at some point before racing
- Conti tires are now all installed and balanced ready to go on the car
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]

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MostMint
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Location: planning a race

Re: 89 Corvette Mostmint #39

Postby MostMint » Wed Nov 06, 2019 10:10 pm

Activity since last update:

Install the RR fender, wiper arms and new wipers
Install engine oil pressure sensor
Bleed the brakes
Block the heater openings with metal
Wire in a cigarette lighter power adapter
Remove some shims to reduce positive front camber, and adjust toe in
Installed hood pins
Block up air leak in roof
Replace fish tank vacuum line with real vacuum line – to throttle body and fuel pressure regulator
Installed longer bolts between the knuckle and rear leaf - lowered about 1/2" but can now adjust this another 1" maybe
Shakedown tests on Friday 11/1 uncovered the brakes still overheating. I first suspected the ABS, but with some troubleshooting and reading the manual I realized the brake booster rod was too long. Removed the master cylinder to grind it down only to find it being adjustable.

All this was in preparation for the track day on 11/2/19, With some help from Fred32v the car got prepped in time and had a chance to run a track day.

We were limited in our stints due to power steering fluid overheating (260 degrees in 10 minutes) and the engine oil not far behind (300 degrees). Trans temp stayed near 190 degrees. Air fuel ratio goes full lean at WOT.

We also had issues with the rusty brake rotors. The Continental tires never made it over 120 degrees, and were definitely not the best gripping tires. The softer springs and sway bars of the base model gave this car some lean under high load cornering, which is not to my liking. Still in my first stint out I managed a 1:21 lap time, which is promising.

We also lost some shims for the hood brackets on track – the bolts were loose and they vibrated out. I should not have assumed the prior owner would have tightened that down. They can be easily replaced.

Overall the car performed well. The natural cornering ability is awesome, and it managed 112 mph on the back straight. You can get back to the throttle way earlier with this car on corner exit than the Saturn. I am very happy with the test results, and plenty of to dos for the car

There were two other Vettes there – C5 and C7, both of which gave me the point by on track. I know people aren't racing at track days but still fun to put our day 1 shakedown car close to its limits and catch the newer technology.

Also discovered that the wiper motor does not work, and the headlights while working, only work on bright and I could not adjust one side down to offset. Got some light rain on the way home fortunately that was all and I was able to drive through it

The car ran 150 miles that day, way more than it had since it was purchased.

Since then I have done some research on the power steering and the lean condition. Regarding lean I checked the fuel pressure and it is in spec. I am still not sure the cause. Right now I suspect one of the following:
1) Bad AFR gauge
2) Wrong fuel injectors
3) O2 sensor sending bad data to ECU
4) MAF sending bad data to ECU

Power steering should be easily resolved with an external cooler. I have tracked down the part #s for the bracket and the factory cooler. If I can obtain a bracket I can probably entertain an aftermarket cooler if I put it in the same place on the car.
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]


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