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C1 Cowl shake

IH2LOSE

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Joined
May 24, 2001
Messages
3,908
Location
We Will All Meet Again
Corvette
1966,and a 1962 thats almost complete
This is a question to the folks who are driving a C1 now


So we are going on a year now since I started driving my 62.

I have always said the car drives like my wifes C5 except its faster

Well I took the wifes C5 on 3 hour drive for a doctors visit,and one of the big differances is that the C5 is absolutely rock solid and doesnt have a rattle in it.


My 62 on the other hand has some rattles and some body flex that i am trying to determine if its normal.


My body is mounted to the frame with some rubber 1/2 rubber grommets compressed to 3/8" and I am wondering if I need to eliminate the rubber and install something more dence

So please try this and tell me what happens in your car

Top down,window down Left hand holing onto the windsheil frame/door post

When I am doing this driving down the average road (not a rut filled pot hole invested road) but just a normal road.

I can feel the gap between the door post and the windsheild closing and opening,Does your do that? is this nor mal in a C1

I have asked local C1 guys this question but they all get excited and start claiming there car is rock solid and not falling apart.


Carlilse 2005 I was talking with this fellow who had a lot of questions about the 62, I could tell he was a car guy for sure because his questions were real mecanical. Any ways one of his questions was how bad is the cowl shake on the car at speed. I said I dont know as I dont have many miles on it and wasnt sure what the term cowl shake meant. Now I think I know what he was asking and I have it and dont like it.

PS any know who this guy is

image.jpg


I did not until a fellow next to me with a Gran Sport pulled me aside and told me.I was hoping to run into him again this year at Carlile but did not see him
 

firstgear

Well-known member
Joined
Oct 11, 2003
Messages
1,895
Location
Norwalk, Ohio
Corvette
15 Z06, 01 Vert, 63 SWC & 60 ALL RED
This is a question to the folks who are driving a C1 now


So we are going on a year now since I started driving my 62.

I have always said the car drives like my wifes C5 except its faster

Well I took the wifes C5 on 3 hour drive for a doctors visit,and one of the big differances is that the C5 is absolutely rock solid and doesnt have a rattle in it.


My 62 on the other hand has some rattles and some body flex that i am trying to determine if its normal.


My body is mounted to the frame with some rubber 1/2 rubber grommets compressed to 3/8" and I am wondering if I need to eliminate the rubber and install something more dence

So please try this and tell me what happens in your car

Top down,window down Left hand holing onto the windsheil frame/door post

When I am doing this driving down the average road (not a rut filled pot hole invested road) but just a normal road.

I can feel the gap between the door post and the windsheild closing and opening,Does your do that? is this nor mal in a C1

I have asked local C1 guys this question but they all get excited and start claiming there car is rock solid and not falling apart.


Carlilse 2005 I was talking with this fellow who had a lot of questions about the 62, I could tell he was a car guy for sure because his questions were real mecanical. Any ways one of his questions was how bad is the cowl shake on the car at speed. I said I dont know as I dont have many miles on it and wasnt sure what the term cowl shake meant. Now I think I know what he was asking and I have it and dont like it.

PS any know who this guy is

image.jpg


I did not until a fellow next to me with a Gran Sport pulled me aside and told me.I was hoping to run into him again this year at Carlile but did not see him
I know....and I know what he is doing....and I am not telling....
 

cbernhardt

Well-known member
Joined
Jan 28, 2005
Messages
192
Location
Lexington, NC
Corvette
62 Conversion Car, Pewter 98, 59 Project
Larry:

I haven’t noticed any cowl shake but I haven’t tried your “test” either. One thing you may need is something more dense to use as body mount cushions. I used 3M Wet or Dry Rubber Squeegee pads, part #05517. They are a very dense black plastic material and will compress very little. These pads are about 0.25” thick and come about 2.75” x 4.5” so you need to cut them to the proper size. I used one at each body mount and then metal shims as needed.

Also, have you tightened your body bolts lately? Some of mine were slightly loose after 10,000 miles.

Try driving your car at a sharp angle over a steep curb cut. If there is any frame twist (which you should not have with the SRIII frame) you will be able to hear some body creaks.

I don't think is is possible to get a C1 as tight as a C5.

Charles
 

magicv8

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Joined
Mar 18, 2003
Messages
656
Location
Going too fast over the hill.

John Mcgraw

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Joined
Feb 18, 2003
Messages
816
Location
Austin Tx
Corvette
1960 Roman red, 1959 resto-rod, 1965 resto-rod
Larry,

My cowl is rock steady, and my car is as tight as any car I have ever owned.
I mounted my body on 3/8" aluminum blocks that are 1.5 X 2" and have a 1/4" rubber pad on top of that. The only rattle in the entire car is the folding top assy rattles when going over some pretty good bumps.

On another issue, did you live with the 225/425 rear springs, or did you swap them out for something softer? I have 250# springs on the rear of mine, but Mike shipped me the 225/425 progressives for my 65 project. Just wanted to get your take on the stiffness of ride on these springs. Someone over on the CF took their car out for it's first trip, and was complaining about the stiffness of the progressive springs.

Regards, John McGraw
 

IH2LOSE

Well-known member
Joined
May 24, 2001
Messages
3,908
Location
We Will All Meet Again
Corvette
1966,and a 1962 thats almost complete
Larry,

My cowl is rock steady, and my car is as tight as any car I have ever owned.
I mounted my body on 3/8" aluminum blocks that are 1.5 X 2" and have a 1/4" rubber pad on top of that. The only rattle in the entire car is the folding top assy rattles when going over some pretty good bumps.

On another issue, did you live with the 225/425 rear springs, or did you swap them out for something softer? I have 250# springs on the rear of mine, but Mike shipped me the 225/425 progressives for my 65 project. Just wanted to get your take on the stiffness of ride on these springs. Someone over on the CF took their car out for it's first trip, and was complaining about the stiffness of the progressive springs.

Regards, John McGraw

John

I have to check my notes on the springs and will post them up tonight,I have been back and fourth with progressive to non progressive, I just put the progressive back in (I will have to check the spring rate) And I am happy.

the first set up I had was way too stiff,I also had the shocks set wrong on there valving. I think I am 3 clicks in now

I am going to remount the body and eliminate the rubber mounts I made for a more rigid mount. I never thought of the rubber squeegees Charles suggested ,but that's what I will use.

There is one more show locally in October,after that I will pull the car apart to remount the body. I finally have my bumpers perfect ,I am not looking forward removing them again to re-set the body.

I also may be over critical of the car,as I met a fellow at carlisle who has a Newman chassis, He is planning a SR111 chassis on another car . I had him over the house to look at the frame on the lift and he took the 62 out for a ride and said it was the tightest C1 he has ever been in.
 

IH2LOSE

Well-known member
Joined
May 24, 2001
Messages
3,908
Location
We Will All Meet Again
Corvette
1966,and a 1962 thats almost complete
Larry:

I haven’t noticed any cowl shake but I haven’t tried your “test” either. One thing you may need is something more dense to use as body mount cushions. I used 3M Wet or Dry Rubber Squeegee pads, part #05517. They are a very dense black plastic material and will compress very little. These pads are about 0.25” thick and come about 2.75” x 4.5” so you need to cut them to the proper size. I used one at each body mount and then metal shims as needed.

Also, have you tightened your body bolts lately? Some of mine were slightly loose after 10,000 miles.

Try driving your car at a sharp angle over a steep curb cut. If there is any frame twist (which you should not have with the SRIII frame) you will be able to hear some body creaks.

I don't think is is possible to get a C1 as tight as a C5.

Charles


Charles

Excellent idea on the squeege and thats what I will use.

Tight is an excellent description of what I am looking for.

Body bolts are tight, But I am finding any stainless steel fastner i used on the car,unless it has a locking nylon nut on it is loosening up. I have been re-setting all of them with the lok-tite blue stuff

Is stainless more prone to lossening up or is it because I used the anti gauling material on them ?
 

magicv8

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Joined
Mar 18, 2003
Messages
656
Location
Going too fast over the hill.
Charles

Is stainless more prone to lossening up or is it because I used the anti gauling material on them ?
I use stainless on everything except suspension, and also use teflon antisieze with no problems. If you use stainless on suspension you may be stretching the bolts. I do Use stainless nyloks on the ends of my rear spring to make the height adjustable, but the bolts are grade8.
 

IH2LOSE

Well-known member
Joined
May 24, 2001
Messages
3,908
Location
We Will All Meet Again
Corvette
1966,and a 1962 thats almost complete
I use stainless on everything except suspension, and also use teflon antisieze with no problems. If you use stainless on suspension you may be stretching the bolts. I do Use stainless nyloks on the ends of my rear spring to make the height adjustable, but the bolts are grade8.


NO Nothing on the suspention,Just other brakets,hood support hinges, Where ever I needed a fastener that was visable I used stainless button head fastners
 

John Mcgraw

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Joined
Feb 18, 2003
Messages
816
Location
Austin Tx
Corvette
1960 Roman red, 1959 resto-rod, 1965 resto-rod
Larry,

I used Stainless bolts on every location on my car, even the suspension. You have to be careful with thread locking liquids on stainless, as most of them will cause so much friction that they will cause gaulling when you go to take them off, and you will have to twist the bolts off to get them loose. I put a shock bolt in one night dry, just for mock-up, but torqued it up. 15 minutes latter I went to remove it and it turned about 3 turns and gauled solid. You have not lived intil you have tried to snap a 1/2" high-strength stainless bolt off! These bolts are about 20% stronger than grade 8. It took a 3 foot long cheater bar on the end of my breaker bar to twist the bolt off. That is the last stainless bolt the I will ever put together without anti-sieze, even if it is coming right back apart. There is a purple thread lock that is sold by Totally Stainless, that they reccomend for stainless, but I will just stick with never-seize and Nylock nuts. I use never-seize even on the small machine screw sizes, and use nylocks on those too.

Regards, John McGraw
 

SebringBill

Well-known member
Joined
Jan 11, 2003
Messages
394
Location
Sarasota FL
Corvette
1957 #3143; 1997 #0993
Yeah, my 57 does that - even when I drive it like a sane person! :W There's a lot of flex in these cars.

And gosh, that guy looks familiar - I've seen him somewhere - but usually on the other side of the car and looking up at the underside of the hood...hmmm.
 

iron cross

Well-known member
Joined
Feb 18, 2003
Messages
245
Location
Dearborn Mi.
Corvette
Unrestored one owner 1962 Black FI car
No Flex,

Being the owner of a Vette that is almost completely original from day one and therefore never cobbled by a previous owner or owners as many on this and other forums could well be. There is no reason for the Vette to flex anywhere and mine dont nor is there any reason why it should. Probably another false idea similar to the one that BB Vettes always over heat. :L
 

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