1958 4 speed

DaveN

Well Known Member
If you got a 4 speed in the trunk what trans came in the car so you could drive it home. I don't know really doesnt make sense to me to put it in the trunk and you would need a 4 spd column. shifter and tunnel cover. Not to be snarky but what did they say we cant put this thing in there its not an RPO yet.
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62_Conv_2-4s

Well Known Member
If you got a 4 speed in the trunk what trans came in the car so you could drive it home. I don't know really doesnt make sense to me to put it in the trunk and you would need a 4 spd column. shifter and tunnel cover. Not to be snarky but what did they say we cant put this thing in there its not an RPO yet.
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My research disproves the 4-speed in the trunk theory. I have no proof this was done. If anybody has proof I would love to see it. My research just shows the 4-speed was available for ordering from the factory into 1958 full size cars very very late in the year. As well as fuel injection. Very few cars were ordered so very few or none have survived. All the cars I have seen have been recreations with no paperwork. The 1958 assembly manual shows just how to create one.
 

Blk61409

Well Known Member
Supporting Member 9
My research disproves the 4-speed in the trunk theory. I have no proof this was done. If anybody has proof I would love to see it. My research just shows the 4-speed was available for ordering from the factory into 1958 full size cars very very late in the year. As well as fuel injection. Very few cars were ordered so very few or none have survived. All the cars I have seen have been recreations with no paperwork. The 1958 assembly manual shows just how to create one.
Need to find the photos, saw one and talked to the owner. He showed me the torn up box for the trans and linkage.
Gotta dig and find. Was at a Goodguys years back
 

62_Conv_2-4s

Well Known Member
Need to find the photos, saw one and talked to the owner. He showed me the torn up box for the trans and linkage.
Gotta dig and find. Was at a Goodguys years back
I guess you could go to the dealership back in the day buy a 4-speed and related parts and put them in your trunk and drive home. That doesn't prove it came that way from the factory unless related original serialized paperwork is there.
 

oldskydog

Well Known Member
Supporting Member 10
If you got a 4 speed in the trunk what trans came in the car so you could drive it home. I don't know really doesnt make sense to me to put it in the trunk and you would need a 4 spd column. shifter and tunnel cover. Not to be snarky but what did they say we cant put this thing in there its not an RPO yet.
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RPO 685, page 277 in the 58 Factory Assembly Manual. The RPO change date is Feb 10, 1958. No special column was used for the 4 speed. A spacing filler tube was inserted into the 3 speed column and the same rubber grommet used on the 3 speed shift lever was glued over the mounting boss on the 3 speed shifter collar. The hole in the tunnel is speced as a 5" diameter hole located 3" from the ceterline reference point of the body and .08" forward of lateral reference line 25.
According to official GM Production Records only 4 passenger cars were built with the four speed option from the factory. If it came in the trunk it was probably ordered from parts but could have been delivered with the car from the dealer.
 

Blk61409

Well Known Member
Supporting Member 9
RPO 685, page 277 in the 58 Factory Assembly Manual. The RPO change date is Feb 10, 1958. No special column was used for the 4 speed. A spacing filler tube was inserted into the 3 speed column and the same rubber grommet used on the 3 speed shift lever was glued over the mounting boss on the 3 speed shifter collar. The hole in the tunnel is speced as a 5" diameter hole located 3" from the ceterline reference point of the body and .08" forward of lateral reference line 25.
According to official GM Production Records only 4 passenger cars were built with the four speed option from the factory. If it came in the trunk it was probably ordered from parts but could have been delivered with the car from the dealer.
Makes sense. The one I saw could have been a dealer installation, I doubt it was one of the four.
 

DaveN

Well Known Member
I should of looked at a 58 assembly manual first I stand corrected. Just seems for 4 cars that was alot of trouble to go through.
 

Blk61409

Well Known Member
Supporting Member 9
Hey looks like there are some very learned 58 detailed members!

Always the best to get proper info!

Meanwhile, if anyone is in need of or is restoring a 58 with tripower the fuel pump pushrod is a different length.

I have a new OEM fuel push rod still in the box I will gladly donate to your rebuild project. Let me know.
 

62_Conv_2-4s

Well Known Member
Hey looks like there are some very learned 58 detailed members!

Always the best to get proper info!

Meanwhile, if anyone is in need of or is restoring a 58 with tripower the fuel pump pushrod is a different length.

I have a new OEM fuel push rod still in the box I will gladly donate to your rebuild project. Let me know.
Do you have the adapter also? I need both rod and adaptor. Thanks, Mike,
 
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Fernbeebe

New Member
The four-speed, introduced on the Corvette in 1957, didn't make it into full-size cars as a factory option until 1959. However, some 1958 Impalas got the manual as a dealer-installed option, which became available in early 1958 as RPO 685.Jun 3, 2023
 
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