My 68 had a pitiful remnant of the underbody tunnel insulation, which I have ordered and plan to install, but there are also "right and left Corvette Underbody Insulation pieces available". Where are these installed? If anyone has an image, that would be helpful. I looked in my assembly manual and could not find this information.

 

Hi c1n,
The early 68 cars left St.Louis with a blanket of insulation installed in the transmission tunnel and a piece of insulation in front of each toe board (right and left).
Later in production a white plastic shield was installed on each side in front of the insulation on the toe boards.
Still later, a rectangular piece of insulation was added that extended from the bottom of those plastic shields rearward to the transmission cross member.
A multi-page service bulletin was issued to dealers detailing the installation of this insulation.
Have you purchased the NCRS Technical Information Manual?. If so the bulletin is included. If not I'll send it to you if you're interested.
Regards,
Alan

 

Alan (AKA guru!),


I do not have that so I would love for you to send me the info. I will PM you my contact info. I purchased the Assembly manual, but there are still many unanswered questions.

 

On cold days you'll wish it wasn't there!

 

We plan mostly to drive her in the warmer months, so that probably will not be a issue. Do you recommend installing them? I have heard pros/cons.

 

I was noticing yesterday how bad the heater is in my 68. Im sure over the years something may have been removed somewhere in my vent system by Bubba. I do need to install all the insulation underneath and the shielding as well. I guess i should buy the manual Alan referred too. thanks for the insight Alan

 

Hi c1n,
I sent you the Service Bulletin information.
With a 68 because of it's "work in progress" nature you REALLY need all the help you can get.
Therefore the AIM, the GM 68 Chassis Service Manual, and the NCRS 68-69 TIM&JG are pretty much invaluable.
Restoring a 68 to it's appropriate configuration for it's time of production is a challenge to say the least.
Folks who have fought their way through the mystery that 68 cars are certainly deserve a lot of credit.
Regards,
Alan

 

If you want to deviate from factory and use todays materials look at the DEI Heatshield.
https://www.designengineering.com//c...-sound-insulat

Don't forget the foam trans collar.

 

thank you Dawson. We have the foam collar. Yours looks GREAT!

 

Good heavens, don't take me seriously!

I can tell you driving across southern California, into Arizona, in late September, I really, really wished there was something more between me and the heat source. I did not want to lay a hand on the shift lever...

 

It gets pretty steamy here in central OK, so YES! We want to control as much heat from coming into the interior as possible.

 

C1nicole,
the insulation configuration may also be different between the SB's and BB's too.
My June '68 car has the factory tunnel insulation, and toe pads on each of the kick ups.
There were no kick up heat shields with BB option.
I have stone shields covering the floor pans back to the seat only.
I'm planning on adding some of the DEI product to the trans tunnel.
My trans tunnel gets awful hot in thee summer.
Drivers floor pan not bad, passenger side gets toasty though.
Fortunately I'm never on that side.
Marshal

 

I wanted to stick with the stock look or as close to stock. My 69 was built in Oct. 68 so it might be similar. First picture is the metal shield that covers the insulation.

RVZIO

 

Realize this is an old thread, but hoping some responses still. This is the setup under my '69. The insulation is starting to fray, so I'd like to replace it. Best option for purchasing the replacement correct for the car setup?

 

My 77 did not have any of these foam pieces, nor any of thes underbody pieces. Chevy stopped all that early in the C3 generation. My 77 has absolutely ZERO heat into the inside of the car, and I run uncoated stainless headers behind a 400 SBC. Here is what I did, and others have done,.....which does not include ANY insulation on the outside of the cabin. I think all that stuff is garbage, and as you stated....is just going to get deteriorated. Also no way to clean around it.

- All following factory pieces must be in place.....and working properly. In 77 this includes the horseshoe collar over the bellhousing (very important), rubber strip around back of hood so that engine compartment heat is not sucked into the wiper bay and then into the heating system. All holes in firewalls must be plugged obviously. All the heater / AC box valves seals and the A pillar vent door seals all must be in great shape. If they are still original.....I can promise you they are junk and useless. This requires complete heater / AC box rebuilds with new seals. Brand new firewall insulation installed....the vendors sell it, its expensive, but if the original insulation isn't working....you are getting heat inside.

- I sprayed two coats of Lizardskin ceramic heat insulation paint on the entire inside of the cabin floor and firewall. I then laid down Lowes Reflectix material on entire inside of floor. Then I bought good Corvette America carpet, with factory style jute backing on top.

I am telling you......I can drive this car in 95 degree weather, and there is ZERO heat transfer into the car. And my car is not equipped with airconditioning. And it has NONE of what I see in this posting.....ie. none of those "shields", no exterior or bottom of car insulation. All that stuff is going to deteriorate being outside the car. My 69 convertible I am restoring will be done the same way as I did the 77, since it worked so well. The only exception is I am going to try NOT to use the Lowes Reflectix on the interior.....It was a pain to clear around gas pedal, etc....if the car gets hot inside without it....I guess I will peel the carpet back out and add it in.

My right foot on the gas pedal is only 5-6 inches from the left uncoated stainless steel header collector and I feel ZERO heat on my foot. Seriously.

All that stuff Chevy started with in the early C3's.....they bagged it midstream through the C3 generation. You could say they did it to save money....maybe so... I am not wasting time and money to put it on my 69.. I think Chevy deemed the stuff useless.....maybe a good idea....but, it didn't work.

 

Ive used the shields and tunnel insulation but never found OEM insulation for the floor boards.....if i find anything ill post it

 

Ecklers has it as well as the aftermarket stuff. So does Paragon along with the fasteners...ild go with Paragon. https://www.paragoncorvette.com/isea...rm=insulation+

 

As you can see from the photos, it's dreadfully EZ if you don't mind pulling the engine/trans.

If you don't give a rat's *** about originality, or how pretty the result, and just want to keep the heat where it belongs..

Take a look at what I did, (best I could) with the engine & transmission IN.

I wrapped the exhaust pipes. Alone it made minimal difference but it did make the car sound better!

I used fender washers and screwed insulated foil wrap to the kicks and the floorboards. I tried adhesives but failed, the fiberglass was saturated with too much oil and crap to adhere despite powerwashing, 2 cans of brake cleaner, etc.

I took some aluminum heat shielding from the junkyard and made "venturis" around the exhaust pipes. Asymmetrical, ugly, and eventually I'll knock them off over some debris in the road. But... I intend to put a
screw clamp or two around the front, bailing wire was what I had at hand.... time was limited.

The #1 thing is to take a pool noodle and stuff it, UP TOP, between the trans and the trans housing so air cannot flow there. That and make sure your hood seal is actually sealing.


GL

 

Thanks. I've noticed my insulation is starting to fray. I'm sure it's not a fire hazard (but please correct me if wrong). Ultimately the fraying part is coming out of the metal shields, so I'm wondering if instead of replacing, I can use some sort of insulation tape to reinforce?

 

Thanks for sharing. I'm definitely not interested in removing engine / trans. I've just noticed my insulation is starting to fray on the sides, so wanted to reinforce what's currently there to eliminate further fraying. I assume I can use some type of insulation tape.....what did you wrap your exhaust pipes with?